Ireland’s wintering waders

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There’s still space for a few Knot

The island of Ireland is a great refuge for wintering waders, washed as it is by the warm waters of the Gulf Stream. It’s just a quick hop across the Atlantic from Iceland for Black-tailed Godwits, Golden Plovers, Redshanks and Oystercatchers. For birds travelling from Siberia, such as Bar-tailed Godwits and Grey Plovers, it’s a longer journey but one that’s well worth making.

If Ireland is such a great destination for shorebirds, why do the latest population estimates reveal a decline of nearly 20% in wader numbers in just five years?

This blog summarises the wader information, published in Estimates of waterbird numbers wintering in Ireland, 2011/12 – 2015/16 in Irish Birds. The totals in the report are split into counts for the Republic of Ireland and Northern Ireland but, given that waders don’t recognise borders, most of the comments in this blog relate to the whole of Ireland. The results for 2011-16 have been compared to the equivalent figures for 2006-11 and set in the context of the totals of wintering waders throughout the East Atlantic flyway, as combined by Wetlands International. The Irish data were collected by the amazing volunteers who make monthly, winter counts for I-WeBS (BirdWatch Ireland & National Parks & Wildlife Service) and WeBS (BTO/RSPB/JNCC in Northern Ireland).

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Headline figures

Fifteen species are considered in this report. The most numerous are Lapwing and Golden Plover, which account for an estimate over 170,000 individuals between them, whilst the smallest contributions are made by Purple Sandpiper (662) and Greenshank (1317). In total, the average estimated number of waders in the winters during the period 2011-16 is 429,170 birds but it should be noted that this total excludes two widespread and common species – Woodcock and Snipe – as well as the enigmatic Jack Snipe. To update previous estimates for these three species, which were last made using distribution and abundance data collected during Bird Atlas 2007-11 fieldwork, it would be necessary to run a special inland survey. There is also some question about Lapwing and Golden Plover numbers, simply because so many of these birds are found in areas that are not covered by monthly waterbird counts.

Biggest changes

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The Irish Sanderling population has increased by 13.2% in five years

The combined average winter maximum count of the 15 wader species examined in the report declined by 102,310 birds (19%) in the five-year period between 2006-11 and 2011-16. This is extremely worrying. If Lapwing and Golden Plover are excluded from consideration, as there is uncertainty about the completeness of counts, there are five species that are of particular concern; Knot numbers dropped by more than 40% and Oystercatcher, Dunlin, Redshank and Turnstone numbers by more than 20%. The Purple Sandpiper population estimate dropped by over 30% but relatively small numbers of this species are encountered around the rocky coast of Ireland. The only species to show increases were Sanderling, Bar-tailed Godwit, Black-tailed Godwit and Greenshank.

In a previous WaderTales blog, there is detailed information about population estimates for Great Britain: Do population estimates matter? In Great Britain there were similar rates of decline for Redshank and Turnstone (measured over an eight-year, rather than five-year period) but much smaller falls for Knot, Oystercatcher and Dunlin. The possible causes of the changes in Ireland are discussed in the paper in Irish Birds. They include flyway-scale declines (e.g. Knot and Curlew) and the possibility that more birds from the east are now wintering on the coasts of mainland Europe (e.g. Dunlin and Grey Plover).

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European context

Blog tableThe table alongside gives an indication of the relative importance of Ireland, Great Britain and, together, the British Isles to the birds that use the East Atlantic flyway during the winter period. The three columns show the percentage of each species found in each of the three regions. Summarised international counts, as used in the paper, were kindly provided by Wetlands International. In the case of four species, Ireland is host to a significant proportion of the Icelandic breeding population (Oystercatcher, Golden Plover, Black-tailed Godwit and Redshank).

Notes: As mentioned earlier, there are questions about the precision of estimates for Lapwing and Golden Plover, although the population trends are reliable. The Ringed Plover percentage seems high (98% for British Isles) but this may well reflect the fact that the Non-estuarine Waterbird Survey has uncovered significant numbers of the species on the open shores of Great Britain. These extra birds are included in the new totals for GB but not in the flyway total. The percentages for Black-tailed Godwit seem low, as discussed further down.

Ireland is particularly important for Golden Plover, Ringed Plover, Bar-tailed Godwit and Black-tailed Godwit, as well as for the Icelandic subspecies of Redshank. Greenshank is excluded because the percentages are below 1% of the flyway population for Ireland and for Great Britain.

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11% of Bar-tailed Godwit on the East Atlantic Flyway spend the winter in Ireland

Although there are important populations of breeding waders in Ireland, the shores and wet fields of the island really come into their own during July and August, when the first ‘winter’ waders arrive, and they only become quiet again in April and May, when the last birds head north and east to nest. A successful breeder is likely only to be away for four or five months, meaning that these waders will spend by far the largest part of the year in Ireland. The island is even more important for immature birds. Young Oystercatchers that arrive from Iceland, Scotland or perhaps Norway when just a few months old are likely to spend the next 30 months in Ireland before making their first trip north. There is a WaderTales migration blog about the Oystercatchers that fly from Iceland: Migratory decisions for Icelandic Oystercatchers.

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Curlew in the Republic

Curlew numbers in the Republic of Ireland illustrate the relative importance of the country for breeding and non-breeding populations. The winter population estimate for Curlew in the Republic is 28,300 but the most recent survey conducted by BirdWatch Ireland and NPWS, as summarised in the WaderTales blog Ireland’s Curlew Crisis, reveals that the number of breeding birds has crashed to just 138 pairs. Accounting for young Irish birds that have not started to breed, and even if we assume that all Irish birds stay in the country for the winter, then the total number of home-grown Curlew seen in non-breeding flocks is at most about 400. This means that every winter flock of 70 Curlew will contain an average of just one Irish bird. Far more deliver their curl-ew calls with a Scottish, Finnish or Swedish ‘accent’. The map below shows the migration pattern for Curlew ringed in or found in Britain & Ireland.

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Black-tailed Godwit

In the table above, it looks as if 18% of Iceland’s Black-tailed Godwits spend the winter in Ireland. This is probably an underestimate of the importance of the Republic of Ireland and Northern Ireland to the species. The flyway total for Black-tailed Godwit is given as between 98,000 and 134,000 in the Irish Birds paper and the percentage figure is based on 110,000. These three figures are almost certainly too high, as they build upon country-based estimates that have subsequently been revised. The true figure is likely to be around 60,000 to 65,000 (J. Gill pers. comm.), which would suggest that the maximum winter count in Ireland of 19,800 represents at least 30% of the islandica Black-tailed Godwits. Add in extra birds that moult in Ireland in the autumn, before moving further south to countries such as Portugal, and other birds that spend spring months on the island, and Ireland becomes even more important for Black-tailed Godwits!

blog BTMost birdwatchers might associate flocks of waders with estuaries but Black-tailed Godwit is an excellent example of a species that also relies on inland fields, either close to estuaries or along river valleys. Whilst undertaking PhD research on Black-tailed Godwits in south-east Ireland, Daniel Hayhow showed that there is insufficient time to find enough estuarine food during the mid-winter tidal cycles, with birds topping up their resources on grassland. You can read more about the energetic consequences of choosing to winter in eastern England, Portugal and Ireland in this blog: Overtaking on migration. Site designation and planning decisions need to take account of the grassland feeding requirements of Black-tailed Godwits and other waders that do not spend all of their time on estuaries, particularly Curlew.

Conservation implications

Some of the issues facing waders may be related to threats that species face in the breeding grounds. However, it may be easier to introduce measures that provide better protection and feeding opportunities in the wintering area, as ways of maintaining populations through the non-breeding season, than it is to deal with problems in the High Arctic. (Although we can all help by reducing carbon emissions, in order to minimise global warming, of course).

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Reading the report, I was reminded of the need to consider a range of conservation issues:

  • Care needs to be taken when considering shoreline developments. These can directly remove habitat or squeeze the width of the intertidal zone.
  • Increased harvesting of shellfish can affect species such as Oystercatcher and Knot and brings risks of introducing alien species and diseases.
  • In the drive to cut carbon emissions, tidal, wave and wind power developments need to be sited in appropriate places.
  • Off-shore harvesting of growing kelp beds has been suggested, as a way of producing fertiliser and biofuels. This process could reduce proetection for beaches and change the availability of resources for species such as Turnstone and Sanderling.
  • Grassland areas need to be considered (and not just estuaries) when planning protection for species such as Curlew and Black-tailed Godwit.

blog RKPaper

Estimates of waterbird numbers wintering in Ireland, 2011/12 – 2015/16. Brian Burke, Lesley J. Lewis, Niamh Fitzgerald, Teresa Frost, Graham Austin, and T. David Tierney. Irish Birds No. 41, 1-12.

There is a complementary paper in British Birds, covering Great Britain. The wader information is summarised in this blog: Do population estimates matter?


GFA in Iceland

WaderTales blogs are written by Graham Appleton, to celebrate waders and wader research.  Many of the articles are based on previously published papers, with the aim of making wader science available to a broader audience.

@grahamfappleton

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Do population estimates matter?

blog top godwitsThis month (March 2019) saw the publication of Population estimates of wintering waterbirds in Great Britain, which includes all the wader species from Little Stint to Curlew. Given that the Wetland Bird Survey already covers about 2000 wetlands and provides annual monitoring, why do we need to know the total number of birds in Great Britain?

I suggest four reasons:

  • If we count the number of Curlew and we have a figure for the European population then we know that Great Britain is responsible for nearly 20% of Europe’s Curlew each winter, thereby strengthening the case for national conservation action;
  • If we have a national figure, then we know that a flock of 2000 Black-tailed Godwit represents (as it turns out) over 5% of the British total, which is a useful criterion when assessing the conservation importance of individual sites;
  • blog GKPopulation totals help to put annual percentage changes into context;
  • And simply because people ask questions such as “how many Greenshank are there in the country during the winter?”

So, here’s the bottom line. In their 2019 review of waterbird numbers in British Birds, a team from BTO, WWT, JNCC & RSPB reveal that an estimated total of 4.9 million waders spend the winter in Great Britain. That’s about one third of all waders on the East Atlantic Flyway. Impressive!

Please note that Northern Ireland figures are included in an upcoming report for the island of Ireland.

Making the counts

The population estimates owe a lot to those who undertake monthly Wetland Bird Survey (WeBS) counts on estuaries, lakes and waterways, during the winter months, year in and year out. Counts from the period 2012/13 to 2016/17 are used in the population estimates that form the basis for the 2019 review. WeBS data have many other uses, as you can read here: Wetland Bird Survey: working for waders.

blog CUFor species of wader that also make use of the open coast, the Non-estuarine Waterbirds Survey of 2015/16 (or NEWS III) provided additional data, updating the NEWS II figures from 2006/07. The vast majority of our wintering Purple Sandpipers are found on open beaches and rocky shores, as well as large numbers of Turnstone, Ringed Plover and Sanderling, together with significant numbers of Oystercatcher, Curlew and Redshank. There’s more about NEWS in this slightly dated blog: NEWS and Oystercatchers for Christmas.

The last assessment of winter wader populations was made by the Avian Population Estimates Panel and published in British Birds in 2013 as Population estimates of birds in Great Britain and the United Kingdom (APEP3). In here, estimates for waders were largely based on WeBS data for the period 2004-09 and NEWS II. The new assessment is presented as Population estimates of wintering waterbirds in Great Britain and also published in British Birds. It uses WeBS information for the period 2012-17 and NEWS III data. Effectively, there is an 8-year or 9-year difference between the two sets of figures.

The biggest losers

blog graphicGreat Britain is extremely important in the context of the East Atlantic Flyway, as is obvious from the fact that the area holds nearly five million waders. The WeBs counts already monitor the ups and downs on an annual basis but this review provides an opportunity to turn the percentages into actual numbers. It is concerning that, over a period representing less than a decade, the average maximum winter count for six of the species that were surveyed dropped by a total of over 150,000. These big losers were Knot, Oystercatcher, Redshank, Curlew, Grey Plover and Dunlin, ordered by number of birds lost, with Knot seeing the biggest absolute decline.

In preparing the new estimates for the British Birds paper, an opportunity was taken to refine the way that populations are calculated, based on Use of environmental stratification to derive non-breeding population estimates of dispersed waterbirds in Great Britain, by Verónica Méndez et al. The new methodology explains some of the differences between percentage changes reported by WeBS and the percentage changes obtained by comparing the latest population estimates to those in APEP3.

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The Knot estimate dropped from 320,000 to 260,000. This figure is higher than might be expected from the counts that take place at sites covered by WeBS, being larger than the ten-year decline of 14% reported in the last WeBS report. Knot are mobile species within the North Sea and Atlantic Coast wintering area and it is possible that British losses may be explained, at least to some extent, by redistribution.

blog oyc graphThe drop in Oystercatcher numbers from 320,000 to 290,000 appears to be less than 10%, compared to a ten-year decline of 12% on WeBS. Improved analysis of NEWS data helped to add some more birds to the open-coast estimate so the 10% fall may underestimate the seriousness of the Oystercatcher situation. The 25-year Oystercatcher decline on WeBS is 26%, which is not surprising if you look at the changes to breeding numbers in Scotland, where most British birds are to be found. There’s more about this in: From shingle beach to roof-top.

blog RKThe Redshank decline of 26,000 is higher than would be predicted from WeBS figures, suggesting a drop of over 20% since APEP3, rather than ‘just’ 15% for the ten-year WeBS figure. This is a species that also features strongly in the Non-estuarine Waterbird Survey and that might explain the difference. Wintering Redshank are mostly of British and Icelandic origin, with the Breeding Bird Survey (BBS) suggesting a ten-year decline of 24% in our British breeding birds.

The Curlew is now globally recognised as near-threatened. The latest winter estimate is 120,000, down from 140,000 in APEP3. The new total represents between 14% and 19% of the European population, which means that we have a particular responsibility for this much-loved species. Only the Netherlands holds more wintering Curlew than Great Britain. Is the Curlew really nearly-threatened? is one of several blogs about Curlew in the WaderTales catalogue at www.wadertales.wordpress/about .

blog 2 DNIt has been suggested that the long-term declines of Grey Plover and Dunlin  may be associated with short-stopping, with new generations of both species wintering closer to their eastern breeding grounds than used to be the case. WeBS results indicate a 31% drop in Grey Plover and a 42% drop in Dunlin, over the last 25 years. There was a loss of 10,000 for both species between APEP3 and the new review, representing declines of 23% and 3% respectively.

The biggest winners

There are four big winners in the period between APEP3 (2004-09) and the new review (2012-16), although, even here, not all as it seems.

The Avocet has seen further dramatic gains. with the estimated wintering population rising to 8,700. The increase is not quite as big as might have been expected, based on the 43% rise seen in ten years of WeBS counts, but it is still a dramatic continuation of a 40-year trend.

The numbers of Bar-tailed Godwit and Ringed Plover are both substantially higher but at least a proportion of each of these changes is linked to the better coverage and more sophisticated sampling methods that were discussed earlier. Bar-tailed Godwit increases may also reflect redistribution around the North Sea.

blog BW graphOne of the consequences of improved statistical techniques, as used this time around, is the apparent decline in the estimated population of Black-tailed Godwit. The new figure of 39,000 is 4,000 smaller than in APEP3, despite the fact that the WeBS graph clearly shows an increase. Interpolation using WeBs figures suggests that the earlier population estimate should have been 31,000, rather than 43,000.

There are other winners too, as you can read in the paper. At the start, I posed the question “how many Greenshank are there in the country during the winter?”.  The answer is 810, representing an increase of 200 since APEP3.

Game species

The estimates for the three wintering waders that are still on the UK quarry list have not changed since APEP3 (published in 2011) as there are no new data available.

Golden Plover: The winter estimate remains as 400,000, as there has been no comprehensive, winter survey since 2006/7. Large numbers of Golden Plover arrive from Scandinavia, Europe and Iceland in the late summer, joining the British birds that choose not to migrate south or west. The GB breeding population is probably less than 50,000 pairs. Most breed in Scotland which has seen a breeding decline of 23% in the period 1995 to 2016 (BBS). Golden Plover is still ‘green listed’.

snipe-headerSnipe (Common): The winter estimate remains as 1,100,000 – a figure that was acknowledged in APEP3 as being less reliable than that of most species. At the same time, the GB breeding population was estimated as 76,000 pairs, indicating at least a 4:1 ratio of foreign to British birds, and that does not take account of the number of British birds that migrate south and west. Snipe are ‘amber listed’ but BBS suggests a recent increase of 26% (1995-2016). There is a WaderTales blog about  Snipe and Jack Snipe.

Woodcock: The winter estimate remains as 1,400,000 – another figure that is not considered to be particularly precise, with much variation between years. The diminishing breeding population is dwarfed by winter numbers, as you can read in this WaderTales blog, with increased attention being given to ways to afford better protection of red-listed, British-breeding birds.

January counts

blog BTThe paper in British Birds also includes a table of January population estimates, to provide data that are comparable to mid-winter counts in other countries. These figures are used in waterbird monitoring for the International Waterbird Census for the African Eurasian Flyway. The main table (and figures mentioned above) are average maximum winter counts (in the period September to March). Black-tailed Godwit is one species that illustrates the difference, with a mean of 30,000 in January and a mean peak count of 39,000. Having moulted in Great Britain, some Black-tailed Godwits move south to France and Portugal in late autumn, returning as early as February. January counts are therefore substantially lower than early-winter and late-winter counts. There is more about the migratory strategy employed by Black-tailed Godwits that winter in southern Europe in Overtaking on Migration.

Looking forward

blog BB coverThe authors have done a tremendous job. They have refined the way that estimates are calculated, they have combined the results from WeBS and NEWS III, and they have delivered population estimates for 25 wader species and many more other species of waterbirds. These population estimates will be used in conservation decision-making until the next set of numbers becomes available. Meanwhile, thousands of birdwatchers will count the birds on their WeBS patches in each winter month, every year. Without them, this paper could not have been written.

Before the next assessment, there will need to be another NEWS survey, to check up on species that use rocky and sandy shore birds, such as Purple Sandpipers, Turnstone and Curlew. Hopefully, there will also be a dedicated survey to assess Lapwing and Golden Plover numbers and perhaps we might find a way to refine the old estimates for Woodcock, Snipe and Jack Snipe.

Paper

Population estimates of wintering waterbirds in Great Britain. Teresa Frost, Graham Austin, Richard Hearn, Stephen McAvoy, Anna Robinson, David Stroud, Ian Woodward and Simon Wotton. Published in British Birds Volume 112. March 2019.

British Birds is a subscription journal. The issue containing this paper can be purchased separately. At some stage, the paper will become free-to-view.

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GFA in Iceland

WaderTales blogs are written by Graham Appleton, to celebrate waders and wader research.  Many of the articles are based on previously published papers, with the aim of making wader science available to a broader audience.

@grahamfappleton

Ireland’s Curlew Crisis

To put the rapid loss of Ireland’s breeding Curlew into context, it’s equivalent to the human population of the Republic dropping from 4.8 million to less than 200,000.

blog muddy edgeIn their paper in Wader Study, the journal of the International Wader Study Group, Barry O’Donoghue and his colleagues reveal the results of the 2015-17 survey of breeding Curlew in the Republic of Ireland. The emerald isle used to be a haven for Curlew but there are now dire warnings that the species could be lost as a breeding species. Various estimates suggest that there were between 3,300 and 12,000 pairs in the 1980s but the current number may be as low as 138 pairs. That’s a fall of 96% in about thirty years.

The latest survey

Surveys in the summers of 2015, 2016 and 2017 focused upon areas that were known to hold breeding Curlew in the previous few years. Sites were identified, using data from Bird Atlas 2007-11 (BTO, BirdWatch Ireland & SOC), the National Parks and Wildlife Service (NPWS) and BirdWatch Ireland, and then extended by 3 km to try to cover any satellite pairs. Additional records were sought from NPWS Rangers (who actively monitor wildlife in their patches across the country) and BirdWatch Ireland branches, supported by a public appeal, using traditional and social media. For details of the survey methods, please see the paper ( link below).

Doing the sums

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Loss of habitat is a major issue for Ireland’s Curlew – blocks of forestry and fragmentation.

Volunteers and staff, who surveyed previously-occupied areas, discovered 128 breeding pairs during the summers of 2015-17. Nationwide publicity added an additional ten pairs, making a minimum count of 138 pairs of breeding Curlew in the whole of the Republic of Ireland. When comparing this figure to historical estimates of national populations, the authors use the conservative figure of 3300 pairs, which is at the lower end of the smallest estimate. This suggests a drop of 96%. If the highest previous estimate of 12,000 pairs had been used, we would be talking about a decline of 99%.

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Curlew chicks are a rare sight – productivity is very low in Ireland

Curlew were recorded at densities of approximately three pairs per 1,000 ha of suitable habitat (0.3 pairs per km2). This suggests that, in these occupied areas of raised bog, wet grassland, wet heath and upland blanket bog, Curlew are living in similar densities to those of the 1980s. They are just found in a much reduced total area.

One positive finding is that 56% of the surveyed Curlew population occurs in protected sites, whether Special Protection Areas (SPAs) or Special Areas of Conservation (SACs) designated under European legislation, and/or Natural Heritage Areas (NHAs) designated under national legislation.

Caveats

The focus of the 2015-17 survey was upon sites that were known to hold Curlew during the period between 2007 and 2014. In an ideal world, there would have been surveys of randomly selected areas in other parts of the country, to establish the number of birds that might have been missed. This would have been an expensive exercise and the consequences are probably not particularly significant because:

  • blog mapDuring the breeding seasons of 2008 to 2011, the whole of Ireland was covered for the Bird Atlas.  The map alongside shows the breeding distribution from this joint BTO, Birdwatch Ireland and SOC project. It shows that there are many areas that no longer have breeding Curlew (black triangles).
  • Curlew are highly site-faithful. Birds are long-lived and unlikely to move between years, so any site occupied in 2011, for instance, would be expected still to hold some of the same birds four years later.
  • Curlew return to breed close to areas where they were raised. The 3-km buffer zone is likely to have picked up young birds setting up their own territories, although precious few chicks fledge successfully these days, anyway.
  • The Curlew is a much-loved bird. A major publicity campaign led to the discovery of only 10 pairs outside the main study areas. If a further 30 pairs were missed (which seems high, representing only a 25% success rate in the call for additional records) then this would only change the ‘96% decline’ headline to a ‘95% decline’.

blog numeniiniWhat has gone wrong?

This blog focuses on the results of the 2015-17 Irish Curlew  survey. Previous WaderTales blogs provide information that sets these declines in context and discuss the problems being faced by the species.

There is a global crisis for large waders as you can read in this review: Why are we losing our large waders?

Each autumn, Irish Curlew are joined by thousands of migrants, largely from Finland, Sweden and Britain. There are still large flocks of Curlew in winter, so it may be hard to persuade people that the Curlew is in trouble. Here are the arguments: Is the Curlew really near-threatened?

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The key issue for breeding birds is habitat loss, as discussed in Mary Colwell’s excellent book Curlew Moon, reviewed here: Curlew Moon.

A review of the associations between Curlew and their habitats suggest that conservation action needs to focus on habitat restoration and reducing the impacts of predators (the latter, at least in the recovery phase): Curlews can’t wait for a treatment plan.

The way that land is grazed has a major impact on breeding Curlew: Sheep numbers and Welsh Curlew.

Acknowledgements and action

blog logoThe 2015-17 survey in Ireland was commissioned by the National Parks and Wildlife Service. Confirmation of the severity of the decline led to the establishment of a Curlew Task Force in January 2017 and a Curlew Conservation Programme, aimed at increasing the productivity of remaining Curlew pairs. CCP logo adapted from original artwork by Anne Harrington Rees.

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Fencing and habitat creation

This study has identified strongholds for breeding Curlew in the Irish Republic and conservation action is currently being implemented in Donegal, Kerry, Kildare, Galway, Leitrim, Mayo, Monaghan and Roscommon. For information on what is an innovative approach to tackling the Curlew crisis, read more about the National Parks and Wildlife Service’s Curlew Conservation Programme here.

Paper

The full paper is in the journal Wader Study. Click on the title below for a link:

O’Donoghue, B., A. Donaghy & S.B.A. Kelly. 2019. National survey of breeding Eurasian Curlew Numenius arquata in the Republic of Ireland, 2015–2017.

Wader Study 126(1): doi:10.18194/ws.00130

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GFA in Iceland

WaderTales blogs are written by Graham Appleton, to celebrate waders and wader research.  Many of the articles are based on previously published papers, with the aim of making wader science available to a broader audience.

@grahamfappleton

The waders of Northern Ireland

blog CU postNorthern Ireland is a great place for wintering waders but the same can no longer be said for its breeding species. There are far too few places left in which Curlew bubble and Snipe drum.

Waders provide some of the best birdwatching spectacles in Northern Ireland, as flocks swirl around coastal estuaries, when the tide rises on a winter’s day. Birds fly in from as far away as Canada and Russia but there are particularly strong links to Iceland, about which there will be more later. Every year, winter counts by volunteers, who help with the Wetland Bird Survey, alert us to the ups and down in wintering populations on loughs and estuaries. Unfortunately, we know much less about breeding species such as Lapwing, Redshank, Snipe and Curlew – four species that feature in a new Northern Ireland survey in the summer of 2019. Although the annual Breeding Bird Survey monitors birds such as Song Thrush and Willow Warbler, waders are just too thinly spread in Northern Ireland for it to be possible to pick up any year-to-year changes. That’s why they need a special survey.

blog L flightWe know that there were some great wader hot-spots in the years 1985 to 1987, when a major Northern Ireland survey took place, and that large drops in numbers were reported in 1999 and again in 2013, after other dedicated surveys, but what is happening now? Are there still places where Snipe drum and Curlew bubble? The BTO in Northern Ireland is asking local and visiting birdwatchers to revisit some of the best places that were identified in previous surveys, to look for breeding waders and to assess the habitats that remain. This work complements work being undertaken by RSPB Northern Ireland. If you think that you may be able to help click here to find more information.

Not looking good?

Although it would be nice to be proved wrong, the expectation is that breeding wader numbers will have declined still further. This means, of course, that any remaining sites that still hold species such as Redshank and Lapwing, are going to be even more important than they were thirty years ago. Pessimism is based on trends elsewhere; numbers of breeding waders are falling throughout the UK and increased agricultural intensification within the Republic of Ireland has caused sharp declines in the focal species of this survey – Lapwing, Redshank, Snipe and Curlew. The following notes give some highlights about Northern Ireland’s waders and point out some of the things that we don’t know (yet).

Lapwing

blog Lap mapThe Lapwing has quietly disappeared from much of Northern Ireland over the last fifty years. The black triangles in the map alongside represent 10-km squares that lost their breeding Lapwings between the two atlases of 1968-72 and 2008-11. Previous Northern Ireland surveys of breeding waders in 1985-87 and 2013 suggest that the number of pairs dropped from an estimated total of 5250 to a total of 860 – that’s a loss of 5 out of 6 pairs. The new survey this summer will update breeding numbers in the species’ heartland areas, as long as sufficient volunteers step forward to help with coverage. (Here’s a link to the results of the 2013 Northern Ireland wader survey.)

Redshank

blog RKThere is no recent estimate for the number of breeding Redshank in Northern Ireland. Across the UK, the Breeding Bird Survey suggests that we have lost 41% of breeding birds since 1995, and the decline was well underway by then. The survey this year provides a good opportunity to learn as much as possible about this threatened species.

In the late summer, the tiny Northern Ireland population is joined by Redshank from Iceland and Scotland. There are also small a number of movements linking Northern Ireland with Wales and England; some of these might be of birds from further east in Europe that were ringed in Britain. Strangford Lough peak counts of over 2000 in October illustrate just how much of an influx there is each autumn.

Snipe

blog SN mapThe lowland wader survey in 1985-87 suggested that the Northern Ireland population of Snipe was about 5725 pairs. By the time of the next survey in 1999, that number had dropped to 3993 and then to 1123 in 2013. That’s a drop of 80%. Snipe seem very sensitive to habitat change, especially drainage. The map alongside shows the change in abundance between 1988-91 and 2008-11 across Britain & Ireland. There is an interesting mix of losses (grey) and increases (orange) in Northern Ireland. It will be great if the 2019 survey picks up some new Snipe hot-spots. One of the key elements of the fieldwork this year is to record habitat data and field-use. What habitats do Snipe still breed in and can these be expanded and replicated elsewhere within Northern Ireland?

blog SN groundThere’s a WaderTales blog about Snipe & Jack SnipeMany of the birds that are seen in Northern Ireland in the winter have flown across the Atlantic to escape the snow and cold of Iceland but there are also large numbers from Scandinavia and continental Europe

Curlew

The Curlew is in huge trouble across the whole island of Ireland. Surveys of random squares in 1985-87, 1999 and 2013 suggest that the number of breeding pairs in Northern Ireland dropped from 5000 to about 500 over the period. There is talk about potential extinction as a breeding species in Ireland and Wales. This may seem ridiculous when you can see flocks totalling 2000 birds around Lough Foyle, on a winter’s day. However, these are almost exclusively migrants, from Finland, Scandinavia and Scotland. One of the hopes is that the new survey will pinpoint new hot-spots for Curlew. There is already concerted action to try to bolster numbers through the Lough Erne Landscape Partnership.

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Other Northern Ireland waders

Oystercatcher: Many wintering Oystercatchers leave Northern Ireland in the spring, heading for Iceland, Scotland or perhaps Norway (more in this wader migration blog). By that time, resident adults will already have moved inland or onto beaches to breed and other birds will have returned from southern wintering areas.

blog RPFlocks of young birds are found on estuaries in the summer, as Oystercatchers typically don’t breed until three years old. We know that the number of breeding Oystercatchers in Scotland dropped by 38% between 1994 and 2017 but English numbers rose by 49% (read more here). We don’t know what’s happening in Northern Ireland.

Turnstone: Wintering birds are mostly thought to come from Greenland and Canada but a December capture of a bird from Sweden suggests that there might be a link to the east as well.

Ringed Plover: The new survey in Northern Ireland is not designed to monitor beach-nesting Ringed Plover. The most recent UK-wide survey of the species was in 2007, when the Northern Ireland population estimate was 147 pairs, similar to the estimate at the time of the previous survey, in 1987. In the same period, numbers dropped in Scotland (-42%) and England (-29%). Link to summary of paper.

blog GP mapGolden Plover: Ireland is a winter destination of choice for many Golden Plover that breed in Iceland. The recovery of a Belgian-ringed bird in 2006 suggests that some birds may arrive from the east as well. Wintering numbers are half what they were 25 years ago, according to WeBS data for Northern Ireland. A few breeding birds can still be found in the western parts of Northern Ireland but they have been lost from most other areas.

Grey Plover: It’s a long way from Siberia to Northern Ireland, so perhaps it is not surprising that not many Grey Plover make it this far west!

Knot: The best place to see Knot is in Strangford Lough, where numbers peak at over 4000 in some winters. The only two foreign-ringed birds were shot wearing Icelandic rings in 1957 and 1975 (when shooting them was legal). Northern Ireland’s wintering Knot probably breed in Greenland or Canada and migrate via Iceland.

Sanderling: The Sanderling that are seen around the coast in winter months, in small numbers, will almost certainly breed in Greenland. Numbers are higher in spring, when birds from further south stop off on their way to Iceland and then Greenland.

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Dunlin: This year’s survey of Lapwing, Redshank, Snipe and Curlew should really include Dunlin, as they share similar breeding habitat. However, it will be a very lucky volunteer who finds a displaying adult. Birds of the schinzii (green arrows) and arctica (yellow) race pass through in spring and autumn but the wintering birds are of the alpina race (orange).

blog WK mapWoodcock: The black triangles in the map opposite show the parts of Northern Ireland that have lost breeding Woodcock in the last 50 years. Data are from Bird Atlas 2007-11 (BTO, BirdWatch Ireland & SOC). In late autumn, birds fly in from counties such as Germany, Norway and Russia. See this blog.

Black-tailed Godwit: All is not gloom and doom in the world of waders; there are six times as many Black-tailed Godwits wintering in Northern Ireland as there were 30 years ago. Great views of these Icelandic visitors are provided at the RSPB reserve at Belfast’s Window on Wildlife. This blog explains why numbers have taken off in recent years.

Bar-tailed Godwit: The Bar-tailed Godwit that are seen in Strangford Lough and elsewhere are birds from northern Norway and Russia. There seems to have been little change in numbers, according to Northern Ireland WeBS counters.

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Whimbrel: A few Whimbrel drop in during autumn passage but far more appear in spring. Most Icelandic Whimbrel can fly straight to West Africa in the autumn but 80% stop off on the way north, many in Northern Ireland (see graphic above). You can read more here.

From Avocet to Pectoral Sandpiper

There is a supporting cast of waders that visit Northern Ireland. This blog provides more information on wader migration: Which wader, when and why?

A call for help

blog habitatAs must be obvious by now, BTO Northern Ireland is looking for volunteers to help with wader surveys in 2019. Sites are discrete lowland wet grassland areas, small enough to survey in one morning. At least two or ideally three visits to each site are required between mid-April and mid-June, with at least two weeks between each visit.

Each field or sub-unit needs to be covered on foot and the number of Lapwing, Curlew, Redshank and Snipe are counted per field. Some additional habitat recording is required, e.g. recording grazing, rush cover and estimating dampness.

blog mapSites are located in five broad areas (see map):

  • Loughs Neagh and Beg
  • Blackwater Catchment
  • Tyrone Fairy Water Bogs
  • Upper Lough Erne
  • Lower Lough Erne (these sites will be covered by the RSPB)

More details are available here, on the BTO Northern Ireland website. There will be a free training session on 29 March. Contact shane.wolsey@bto.org if you have any questions or would like to volunteer.

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GFA in Iceland

Graham (@grahamfappleton) has studied waders for over 40 years and is currently involved in wader research in the UK and in Iceland. He was Director of Communications at The British Trust for Ornithology until 2013 and is now a freelance writer and broadcaster.

 

Black-tailed Godwit and Curlew in France

In July 2018 there was a call for people to express their opinions on the issue of hunting Black-tailed Godwits and Curlews in France. This blog aimed to bring together some background to inform the discussion. The government decided to maintain the current situation until 30 July 2019: to shoot Curlew in some circumstances but to maintain a ban on shooting Black-tailed Godwits. There will be another review in the summer of 2019.

Problems for large waders

Oct 2017The Numeniini is the group of waders that includes curlews, godwits and the Upland Sandpiper. Globally this group is under threat – two species of curlew are probably already extinct. These long-lived species are threatened by pressures during the breeding season and, in some parts of the world, reduced annual survival.

Click here to read a blog about the threats to large waders.

Conservation of migratory species

The Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA) is an intergovernmental treaty dedicated to the conservation of migratory waterbirds and their habitats across Africa, Europe, the Middle East, Central Asia, Greenland and the Canadian Archipelago.

Developed under the framework of the Convention on Migratory Species (CMS) and administered by the United Nations Environment Programme (UNEP), AEWA brings together countries and the wider international conservation community in an effort to establish coordinated conservation and management of migratory waterbirds throughout their entire migratory range.

Eurasian Curlew

RC picEurasian Curlews are listed as Near-Threatened by BirdLife/IUCN. Shooting of this species has ceased in western Europe, apart from France. A moratorium (pause) was put in place in France in 2008 but that was amended in 2012 to allow shooting on the coast, which is where many of the Curlews are to be found. Shooting of Curlews ceased in Great Britain in 1981, in Northern Ireland in 2011 and Ireland in 2012. The partial moratorium in France was extended until 30 July 2018 and then to 30 July 2019.

LPO (Ligue pour la Protection des Oiseaux), the BirdLife International partner in France, argue that shooting of Curlew should cease or at least that that there should be another moratorium, for at least three years, covering coastal as well as inland areas.

Jan 2018 extinction riskAn AEWA (Agreement on the Conservation of African-Eurasian Migratory Waterbirds) plan of 2015 called for an immediate end to hunting and for an Adaptive Harvest Management process to be set up to recommend if any hunting could be sustained. Continuedcurlews in france shooting in France must surely be in contravention of the international plan? Here’s a link to the AEWA Action Pan for Eurasian Curlew.

Tens of thousands of Curlew spend the winter in France, migrating here from across Northern Europe. The purple dots on the map alongside represent the recovery locations of Curlew ringed in Britain and Ireland. Many of these ringed birds have been found in breeding areas, especially Finland, but there are plenty of reports in coastal France, most of which are birds that have been shot.

Click here to read a blog explaining why we should be worried about Curlews.

Black-tailed Godwit

subspeciesTwo subspecies of Black-tailed Godwit spend time on French estuaries; limosa and islandica. The size of the islandica subspecies is increasing, as the breeding range in Iceland expands (blog about this) but the number of limosa is in rapid decline. Limosa birds that spend time in France breed in the Netherlands and surrounding countries, including a small number that breed in the washes of East Anglia. You can read about the 75% decline in the Dutch breeding population in this blog.

Picture7Agreements signed by partners of AEWA and members of the European Union included a five-year moratorium (pause) in shooting of Black-tailed Godwits in the whole of France. This was extended for a further five years, up until 31 July 2018 and then for one more year, until 30 July 2019.

It is hard (or even impossible) to separate islandica from limosa Back-tailed Godwits and we know that they occur in mixed flocks. Scientists have been colour-marking Black-tailed Godwits of both subspecies for many years and birdwatchers can help to assess the relative threat to limosa by reporting colour-ring sightings. You can read more about the value of colour-ring sightings here:

Godwits & Godwiteers 

Project Godwit

blog ManeaBlack-tailed Godwit is still on the French quarry list but there is an ongoing hunting moratorium (pause) that, as for inland Curlew, ended on 31 July 2018 but was extended to 30 July 2019.

LPO argue that, given that it is not possible to distinguish the two subspecies, Black-tailed Godwit should be removed from the quarry list or, alternatively, that there should at least be another moratorium (of at least three years).

Result of the consultation

As indicated at the start of this blog, a decision was made in July 2018 that nothing would change for another year. There would be a complete ban on the hunting of Black-tailed Godwit in France until 30 July 2019 and permission was granted to continue to hunt coastal Curlew. Link here.

Evidence is being collected by conservation scientists that will hopefully inform the decisions that are made as to what should happen after 30 July 2019.


GFA in Iceland

Graham (@grahamfappleton) has studied waders for over 40 years and is currently involved in wader research in the UK and in Iceland.  He was Director of Communications at The British Trust for Ornithology until 2013 and is now a freelance writer and broadcaster.

Curlew Moon

In deference to the scientific papers that underpin them, stories in previous WaderTales blogs are expressed in facts and correlations, not emotions. This blog, which is in part a review of Curlew Moon by Mary Colwell, is a little more personal.

Curlew Moon – a special book

book coverCurlew Moon, is based upon Mary Colwell’s walk from the West of Ireland to the East of England, raising money for the BirdWatch Ireland, BTO, RSPB and GWCT Curlew appeals and researching material for the book. She takes the reader into the stripped-bare peat bogs of central Ireland, shares the excitement of feeling the beating heart of a newly-ringed Curlew and meets some great people who care about Curlews in their own, local patches. The book is a fascinating blend of Curlews, agricultural history, culture and poetry – written beautifully.

Global problems

blog flightCurlews are large waders that live long lives. The family to which they belong, the Numeniini, is not coping well with the speed with which the world is changing. Two species of curlew are probably extinct – functionally if not actually – and the godwit members of the family are faring little better. The blog Why are we losing our large waders? summarises an excellent review by the BTO’s James Pierce-Higgins and colleagues from thirty other organisations/institutions around the world. In it, they assess the stresses that humans are imposing upon curlews & godwits, through direct activities and the impact we all have on the climate. It’s not just our Eurasian Curlew that we need to worry about.

British breeders and foreign visitors

Mary’s walk from west to east began on 21 April 2016, so the bulk of her story focuses upon the Curlew breeding season. The book, however, starts with a couple of trips to see flocks that consist mostly of wintering birds, in Norfolk and the Moray Firth.

blog Wash

The Wash estuary, the bite out of the east coast of England, between Lincolnshire and Norfolk, holds up to a quarter of a million waders in some months, with a peak annual count of 8,000 or so Curlew. Mary went to Snettisham to see some of these Curlews for herself. Most of the birds had crossed the North Sea in the autumn, from countries such as Finland, Germany and even Russia. There are British-bred birds here too but these are in a minority. The WaderTales blog Is the Curlew really near-threatened? is also rooted in Norfolk. If a Curlew can live for 32 years and there are flocks of 1000 in Norfolk, why are they red-listed as a species of conservation concern?

blog Bob Swann

Tagging a Curlew: Mary Colwell, with Ron Summers of the Highland Ringing Group

Mary’s next trip was to the Moray Firth, where she met up with members of the Highland Ringing Group. Here, Bob Swann and his colleagues caught eight Curlew, in a mixed cannon-net catch of waders and gulls. I love the way that the strange activities of these dedicated, well-trained volunteers are described! The Curlews were all fitted with geolocators, to track their movements over the next twelve months. A previous bird had revealed a fascinating journey to Sweden and back, with only 53 days on her breeding grounds. She spends by far the largest part of each year in Scotland. What will these new birds tell us about the lives of our largest waders?

Habitat and predators

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An Irish marsh, freshly prepared for the peat-cutting machines

The long walk started in Ireland, where breeding Curlew are closest to extinction. In the Irish Republic, the latest survey revealed a breeding population of 124 pairs, down from perhaps 4,000 pairs in the 1980s. I had read about the causes of the demise of the Irish Curlew but Curlew Moon helped me to understand them. I could hear the silence that made an old man cry, I could see the rows of peat-devouring machines and I could understand the impact of changing farming methods. There may have been economic benefits (for some), associated with funding from the EU and the cessation of the Northern Ireland troubles, but Curlews have not been able to keep up with the changes that prosperity has delivered.

blog adult on nest

Curlew nest, tucked away in some long grass

The situation is not dissimilar on the other side of the Irish Sea. In a paper reviewing associations between Curlew numbers in Britain and changes that may be causing them, Sam Franks and BTO and RSPB colleagues conclude that Curlew are less numerous and have shown greater population declines in areas with more arable farming, woodland cover and higher generalist predator abundance. Putting it simply, the key thing that conservationists should focus on are “habitat restoration and reducing the negative impacts of predators”. There’s more about this in Curlews can’t wait for a treatment plan.

blog chickIn the book, Mary describes the disappointments experienced by the Curlew Country team in Shropshire; in the years 2015 and 2016, 32 nesting attempts yielded no fledged chicks. Foxes were the main problem – with additional pressure from other predators and farm machinery. There was better news in 2017, perhaps associated with more fox control; three chicks were raised naturally and others were head-started. By taking ten eggs at the point of laying, replacing them with dummy eggs, and switching again at the point of hatching, the team increased the total number of fledged chicks to eight. After two blank years, this was an encouraging success for the team.

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Grouse

Much has been written about grouse moors and waders. As Mary moved on towards the Staffordshire Moors and then The Peak District she knew that she would “come face-to-face with some of nature conservation’s most bitter conflicts”.

blog nest grouse moor

Curlew, nesting in the short grass on a grouse moor

I shall not attempt to summarise the Curlews and Controversy chapter – read it for yourself – but Mary, who describes herself as “left-wing, vegetarian with vegan tendencies” and who has never even held a gun, found more Curlew on a grouse moor she visited in early April than anywhere on her walk.

By removing predators, burning heather to encourage new growth and keeping trees at bay, shooting estates create habitat that is good for both Red Grouse and Curlew. It also suits Hen Harriers which feed on the youngsters of both species. And that’s when the potential for conflict really starts!

One of the arguments in favour of grouse shoots is a financial one. If there is no shooting, land-owners are going to want a return on their investments and an obvious replacement is serried rows of non-native forestry. This will not only take away moorland but will also have effects beyond the woodland edges, due to the actual and perceived risks of predation.

Making space

blog NI RSPB

Mary with Neal Warnock of RSPB Northern Ireland

There are conversations to be had about how space can be made for Curlews in upland farms and moors, while enabling these areas to be farmed profitably, or at least without loss. As Mary points out, if one farmer is being compensated for managing land in ways that suit breeding waders, the chance of success becomes vanishingly small if a neighbour receives subsidies to grow carbon-capturing trees. How can we ensure that planners understand the bigger picture?

Curlews need plenty of space and three WaderTales blogs talk about how farming and habitat heterogeneity might be impacting upon their success.

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Rachel Taylor, downloading data from a tracking station

In Curlew Moon, Mary writes about a day in Migneint moor, which lies to the south of Mynydd Hiraethog (mentioned above). Here, she and Rachel Taylor of BTO Cymru went in search of tagged Curlews that are contributing to a study Rachel is running with Steve Dodd of the RSPB. Four males have revealed the scale at which the species operates – “One bird flew a staggering 21 km away to a favoured feeding spot”. A paper in Wader Study by Steven Ewing and colleagues suggests that birds are highly variable in the way they use the landscape; two of their males travelling 1.6 km each evening but one bird staying close to the nest. Curlews need more space than perhaps we appreciated.

The people who care

In researching for her new book, Mary Colwell seems to have learnt as much about the people who study and love Curlew as she has about these special birds.  From her close encounters with cannon-netters, using geolocators to chart Curlews’ movements, through to gamekeepers who control predators, Tom Orde-Powlett managing a grouse shoot and others who are improving breeding habitats and monitoring nesting success, she focuses upon the respect so many people have for this fast-disappearing species. At the same time, she shares her own passion for this emblematic bird, the haunting calls of which echo across too many abandoned moors.

The Book

Curlew Moon is published by William Collins. ISBN 978-0-00-824105-6

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 GFA in Iceland

WaderTales blogs are written by Graham Appleton, to celebrate waders and wader research.  Many of the articles are based on previously published papers, with the aim of making wader science available to a broader audience.

@grahamfappleton

 

 

Scottish Wader Woes

The report on Scotland’s terrestrial bird species, covering the period 1994-2016, does not make easy reading for wader lovers. All but one species is contributing negatively to the upland bird indicator, with declines of over 40% for breeding Lapwing, Curlew, Dotterel, Oystercatcher and Golden Plover. In this short blog, there are links to information that helps to explain what might be going wrong for Scotland’s waders.

The full report is available on the SNH website (https://www.nature.scot/information-library-data-and-research/official-statistics/official-statistics-terrestrial-breeding-birds)

One species has been increasing – Snipe up 22%

snipe abundance changeThe one spot of good news is that breeding Snipe numbers in Scotland have risen over the period 1994 to 2016. This is particularly encouraging, given declines in much of the rest of Britain and Ireland, as you can see in the map alongside and read in this WaderTales blog Snipe and Jack Snipe in the UK and Ireland.

In the map, produced for Bird Atlas 2007-11 (BTO, BirdWatch Ireland & SOC), pink colours show abundance increases and grey areas show decreases.

Lapwing declines largest – down 63%

GHH pictureWhen a widespread species such as Lapwing is in decline this is bad news. Subtle difference in the way that lowland valleys are farmed may be part of the problem, as illustrated in this WaderTales blog, based on work by Mike Bell, written up with the help of John Calladine, of BTO Scotland: 25 years of wader declines.

Curlew down 62%

Blog Jill PThe Curlew is causing huge concerns in Ireland and Wales, where conservationists are contemplating its disappearance as a breeding species. Scotland holds much larger numbers but a decline of nearly two-thirds suggests that there are major problems here as well.

Two WaderTales blogs tell the Curlew story. Is the Curlew really near-threatened explains why we should be so worried about what is happening and Curlews can’t wait for a treatment plan summarises a BTO-led paper from Sam Franks and colleagues which attempts to explain the patterns we are seeing in the species’ decline.

Dotterel down 60%

IMG_2123

Alistair Baxter

Most of the information about Scotland’s breeding birds comes from annual data collected by volunteers contributing to the Breeding Bird Survey (BBS), organised by the BTO, in partnership with JNCC and RSPB. Dotterel is different; here the counts are dependent on dedicated surveys of Scotland’s high-mountain plateaus. Concern for the species is very much linked to climate change but this blog, based on a paper by the RSPB’s Daniel Hayhow and colleagues, shows that there may well be other reasons for the species decline: UK Dotterel numbers have fallen by 57%. The figure for the decline may be slightly out-of-date but the blog isn’t.

TGG OycOystercatcher down 44%

In England, the latest BBS report shows an increase of 50% in Oystercatcher numbers but, in Scotland, where there are far more breeding pairs, the species is in decline. Oystercatchers: from shingle beaches to roof-tops looks at the history of the species’ spread from the shoreline, into the hills and onto roofs and considers the role of predation in recent declines.

Golden Plover down 43%

As noted in the press release about the new report ‘The golden plover population has declined by 43% since 1994 and stands at its lowest point since the BBS survey began. Declines may be linked to climate change, in part due to impacts on the abundance of craneflies during the breeding season. There are two interesting papers about this by James Pearce-Higgins and colleagues.

golden ploverPearce-Higgins, J.W., Yalden, D.W. & Whittingham, M.J. 2005. Warmer springs advance the breeding phenology of golden plovers Pluvialis apricaria and their prey (Tipulidae). Oecologia 143: 470–476.

Pearce-Higgins, J.W., Dennis, P., Whittingham, M.J. & Yalden, D.W. 2010 Impacts of climate on prey abundance account for fluctuations in a population of a northern wader at the southern edge of its range. Global Change Biology 16: 12–23.

Common Sandpiper down 39%

The Breeding Bird Survey does not properly capture trends for species found mostly along rivers. Data for Common Sandpiper are derived from the BTO Waterways Bird Survey and the Waterways Breeding Bird Survey.

Why no Redshank?

Unfortunately, breeding Redshank are now patchily distributed across Scotland, with too few being picked up by BBS surveyors to make a contribution to Scottish population indices. Across the UK, the latest published BBS decline is 38%. UK graphs for Oystercatcher, Redshank and Curlew are shown below.

UK BBS


GFA in Iceland

WaderTales blogs are written by Graham Appleton, to celebrate waders and wader research.  Many of the articles are based on previously published papers, with the aim of making wader science available to a broader audience.

@grahamfappleton

 

Sheep numbers and Welsh Curlew

Blog Jill PThis paper from Ian Johnstone and RSPB colleagues, in the BTO journal Bird Study, provides some interesting evidence as to how the distribution of breeding Curlew in Mynydd Hiraethog (North Wales) relates to habitat. Amongst other things, they conclude that the amount of sheep grazing is critical to the future recovery of the species in this area.

Correlates of Distribution and nesting success in a Welsh upland Eurasian Curlew population by Ian Johnstone, Dave Elliot, Chris Mellenchip & Will Peach. Bird Study https://doi.org/10.1080/00063657.2017.1411466

The bigger picture

old blogsInternationally, the Eurasian Curlew is designated as near-threatened because of the rapid declines in numbers across the species’ range. Irish conservationists are worried that the species may soon disappear as a breeding species and Welsh birds may not be many years behind, if the current population trajectory continues. For more background see this WaderTales blog: Is the Curlew really near-threatened?

While conservation measures such as ‘habitat improvement’ and ‘predator control’ are already being used in specific recovery projects it is still important for scientists to use current evidence to tease apart the factors that may be affecting the distribution and breeding success of Curlews. An earlier WaderTales blog, summarising a paper by Sam Franks and colleagues from BTO and RSPB, concludes that habitat changes and predator impacts have combined to cause declines and lists some of the specific factors involved. Across Great Britain, they found that semi-natural grasslands support the highest densities of Curlew and population declines were highest in areas with more crows and foxes. See this WaderTales blog: Curlews can’t wait for a treatment plan.

The Curlews of Mynydd Hiraethog

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Looking down from the moorland of Hiraethog into intensively manged farmland in the valley

Mynnydd Hiraethog is a discrete 150 km2 upland block of high grass and heather moorland with adjacent lower, enclosed and largely agriculturally improved farmland. The area is managed for livestock farming and forestry and nearly half of the moorland was designated as a Site of Special Scientific Interest (SSSI) in 1989 because of the importance of its upland habitats for birds. The mountains of North Wales have long been grazed by sheep, with peak densities occurring in the Hiraethog region in about 1999. Agreements with farmers have reduced stocking levels, in order to enable overgrazed habitats to recover.

This study focuses upon the relationship between habitat variables and Curlew numbers in a landscape containing agriculturally improved farmland and moorland that was partly protected and subject to grazing reductions for nature conservation. Thirty, random 1 km squares, stratified by historical population trend, were surveyed for Curlew density and nesting-success. Habitat-related and predation-related variables such as ground cover, plant communities and crow numbers were collected to test for associations between Curlew distributions and environmental variables.

Blog BelseyCurlew numbers in the study area declined by 29% between 1994 and 2008, which is much lower than the decline of 46% across the whole of Wales in the same period (Breeding Bird Survey). By studying a mix of squares in which Curlew numbers had increased, remained stable and declined, the researchers were able to maximise the power of the tests. As expected from previous studies, densities in the moorland edge were higher than in improved farmland (there’s plenty of detail in the paper). There were fewer Curlews in areas with higher vegetation density, with 78% of pairs in survey squares with below-average ground cover. In dense cover, prey may be harder to detect and access.

By focusing on key plant species that are associated with particular habitat types, the team were able to identify links with Curlew abundance and nesting success. As predicted, they found that breeding abundance was positively related to the presence of mat-grass Nardus stricta, which grows as tussocks and is associated with rough grazing. Nesting success was higher in areas with more cover of deer-grass Trichophorum germanicum, a sedge that is found in bogs and on wet moorland. Blanket mires are known to support populations of surface invertebrates, which are particularly important to chicks.

GT predatedWoodland may provide look-out perches and nesting habitat for avian predators and den-sites for foxes and other studies have shown that waders are less numerous close to woodland, either because of a direct predation effects or because waders avoid areas of perceived danger (as discussed in this WaderTales Blog – Mastering Lapwing Conservation). There was only weak evidence of reduced Curlew abundance in areas with more woodland in the Hiraethog area. Fox and crow control takes place across the whole area (for livestock protection) so there was insufficient variation to look at any effects that predator numbers may have on distribution or breeding success.

What next for Curlews?

On Hiraethog, much of the rough grazing, characterised by Nardus stricta, and mire, characterised by Tricophorum germanicum, is contained within the SSSI, and the RSPB authors affirm that these habitats should continue to receive protection from developments such as agricultural intensification and tree planting.

Curlews preferentially occupy locations within the moorland/farmland edge. Historically there has been concern over impacts on upland breeding waders of high sheep grazing pressure but more recently worries have been expressed over under-grazing of some upland habitats in Wales. In Hiraethog, the fact that fewer breeding Curlews were found in areas of dense vegetation is consistent with under-grazing having potentially contributed to a decline in habitat suitability.

somewhere else

Welsh moorland, with blanket bog in the foreground and a mosaic of grassland in the background

There was a 46% drop in sheep numbers in Hiraethog between 1995 and 2009, according to figures from Natural Resources Wales, in order that priority habitats would recover from historical overgrazing. This reduction in grazing pressure has probably resulted in increased vegetation density and reduced sward suitability for Curlew. Vegetation density was higher inside the SSSI than in comparable habitats outside, particularly for habitats preferred by Curlew such as heath and rough grazing.

The authors recommend that management of the SSSI for Curlew should include increases in livestock grazing of appropriate type and intensity.  These should be targeted at rough grazing and mire, in areas that have a history of Curlew occupation and that have high current vegetation density. It is hoped that modest and localised increases in grazing pressure can reduce vegetation density without negatively impacting on protected habitats. If successful, and implemented in an experimental manner, then similar treatments may well be trialled elsewhere.

The full paper can be accessed here

Correlates of Distribution and nesting success in a Welsh upland Eurasian Curlew population by Ian Johnstone, Dave Elliot, Chris Mellenchip & Will Peach. Bird Study https://doi.org/10.1080/00063657.2017.1411466


 GFA in Iceland

WaderTales blogs are written by Graham Appleton, to celebrate waders and wader research.  Many of the articles are based on previously published papers, with the aim of making wader science available to a broader audience.

@grahamfappleton

 

 

 

25 years of wader declines

This article summarises a Bird Study paper arising from a 25-year Scottish study of breeding Lapwing, Oystercatcher, Redshank & Curlew. The story is set against a backdrop of a changing farming landscape.

RC LapThe interesting and sobering feature of this paper about breeding waders by Mike Bell and John Calladine is that its focus is a ‘normal’ area of farmland in Scotland. If you’ve taken the A9 north of Stirling, through Strathallan, then you’ll have driven past the fields. Perhaps you might even have noticed displaying Lapwing, Oystercatcher, Curlew and Redshank? Over a 25-year period, the number of breeding waders in this valley and another one that runs northwest and that can be seen from the B827 has dropped from 600 pairs to just 76 – that’s a loss of 87%, or over 20 pairs per year.

So, what has changed in this part of Scotland that might be linked to these declines? The authors conclude that the reduction in numbers can be linked to changes in field management. Put simply, there are too few bare fields in the spring for Oystercatcher (down 95%) and Lapwing (down 88%). These two species hide their nests in ‘plain site’; they watch out for predators, take off early and hope that the eggs are coloured cryptically enough to avoid detection. Having left their nests, they attempt to deter and/or distract prowling crows etc.  Redshanks (down 87%) and Curlew (down 67%) have also declined, even though they hide their nests in long grass, about which more later.

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Lapwing declines in the Strathallan area are not that much different to those that have been charted across much of Britain & Ireland

In for the long haul

In a survey in the late 1980s, this area of Strathallan held an important assemblage of farmland breeding waders, with particularly high densities of nesting Lapwing. Land use in the valley is predominantly agricultural, with a mixture of arable fields and grazing by sheep and beef cattle. It is a relatively open landscape with few hedgerows, some scattered shelter belts and small conifer plantations.

KS RedshankThis study started in 1990, when breeding densities of nesting Oystercatcher, Lapwing, Redshank and Curlew in the core area were still high, at 11.7, 35.6, 4.7 and 3.3 pairs/km2 respectively. Unlike a PhD project, which might include three years of data, Mike Bell has kept this survey going for 25 years. Mike is the volunteer Regional Representative for the British Trust for Ornithology’s Perthshire region.

Breeding waders within a core area of 65 fields and a small amount of wet fen were surveyed annually from 1990 to 2015. The field sizes were small, by modern standards, with only five fields larger than 20 ha. An additional 1 km2 of lowland mixed farmland was surveyed in most years, 4 km2 of moorland rough grazing was surveyed in four years and another 5.3 km2 of enclosed and unenclosed rough grazing and moorland was surveyed at the beginning and end of the survey period only.

Land management and usage were recorded for each field on the first visit in April or early May. Spring sward height in each field was recorded as one of three categories: no vegetation, short (<10 cm) or long (>10 cm). These sward categories comprised the following field types:

  • bare – ploughed or tilled land with no emergent vegetation
  • short – managed grass for grazing or mowing for hay or silage, rough grass, rush pasture, spring arable, setaside/fallow.
  • long – managed grass, rough grass, rush/pasture, setaside/fallow, heath/moorland, marsh/wetland, unmanaged rank grassland and woodland/scrub.

Where to find waders in Strathallan

In the early 1990s, Strathallan supported around 36 Lapwing pairs/km2 across the core study area, which is comparable with some of the highest densities reported anywhere in the UK. During the 25-year study, as the numbers of Lapwing, Oystercatcher, Redshank and Curlew declined, an increased proportion of the remaining breeding waders became restricted to areas with fields classed as ‘bare’ in spring, while the greatest losses were in fields with ‘short’ and ‘tall’ spring sward heights (see figure).

graphic

Changes in breeding densities of waders in Strathallan, on fields with different sward heights

Breeding densities of Curlew were low throughout the study area and, although overall numbers declined, there was low power to detect statistically significant changes. There were different patterns of change for Lapwing, Oystercatcher and Redshank within fields of different spring sward heights:

  • The least marked changes were in fields with no vegetation in spring.
  • Fields with short swards showed the largest declines.
  • The tallest spring sward heights supported the lowest densities of the three wader species, with Redshank present generally at low densities in all vegetation categories.
UK BBS

UK-wide Breeding Bird Survey trends for Oystercatcher, Redshank and Curlew. BBS is organised by BTO in partnership with JNCC and RSPB.

A changing farmland landscape

Sward heights reflected changing farming methods. Looking at the fields in terms of cropping regimes.

  • The highest densities of Oystercatcher were in spring-sown arable crops.
  • Rush pasture was the most favoured field type for Lapwing and Redshank at the start of the study but the amount of this habitat declined during the study, as farmers created semi-permanent pastures for over-wintering sheep. When this happened, birds became more restricted in their nesting distribution.
  • By 2015, very few fields were still under a crop rotation of grass and spring arable, that would have delivered a mosaic of sward structures. By this time, half of the Lapwing pairs were nesting in just four fields.

Breeding success

The breeding success of Lapwings was estimated in five sample fields that could easily be observed from roads or tracks without disturbing the adults. Lapwing productivity was less than 0.60 young fledged/pair (the bench-mark for a typical stable population) in all but three years and it was less than 0.25 young fledged/pair in 14 of the 22 years. With very low recruitment rates, it is not surprising that the Lapwing is in decline.

There are several WaderTales blogs about Lapwings breeding in lowland wet grassland, including A helping hand for Lapwings. A full list of WaderTales blogs can be found here.

What is changing?

TGG Oyc

The changing fortunes of Oystercatcher are discussed in this WaderTales blog

Within a mixed arable-pasture farmland environment, bare field and short swards in spring appear to be important to breeding waders. Losses of these preferred habitats type don’t appear to fully account for the decline in numbers, however.

Alongside changes to farmland habitats, other potential factors that could have contributed to the decline of the wader population in Strathallan include an increased incidence of poor spring weather, increased disturbance (including from dog-walkers in some fields in some years) and an increase in predators. Mike Bell thinks that one of the reasons for a possible link between productivity declines and wet weather is that birds are nesting in sub-optimal (long) grass and hence more affected by wetter conditions. He writes about this and potential reasons for increased disturbance in an upcoming article in Scottish Birds. A link to the Scottish Birds article will be included when available.

Densities of avian predators increased in Strathallan during the study period, with higher breeding densities of Carrion Crow and Buzzard and an increasing frequency of bigger flocks of non-breeding crows. There was no detectable change in breeding success during the study but it is possible that nest success was already depressed by predation when the study commenced.

A relentless decline

GHH pictureAlthough previously identified as a good area for breeding waders, in a Scottish context, there is nothing unique about this Strathallan study area. It is good to see these issues explored in Bird Study, the BTO journal. I am sure that the editor, Ian Hartley, will have been pleased to publish a paper based on a nice mix of dedicated fieldwork and scientific analysis – that’s what the BTO is all about.  If you want to understand the (not yet fully explained) sad demise of breeding waders in Scotland, check out the figures in the paper. These show a relentless, 25-year decline in nesting densities across a range of habitats and some less-than-subtle changes in the way that fields are now managed.

Here’s a link to the paper:

The decline of a population of farmland breeding waders: a twenty-five-year case study by Michael V. Bell & John Calladine in Bird Study, 64:2, 264-273 DOI: 10.1080/00063657.2017.1319903


 GFA in Iceland

WaderTales blogs are written by Graham Appleton, to celebrate waders and wader research.  Many of the articles are based on previously published papers, with the aim of making wader science available to a broader audience.

@grahamfappleton

 

 

Wetland Bird Survey: working for waders

Red-listed Curlews, Scottish Oystercatchers, a boom in Black-tailed Godwits and the need for safe roost sites. Here’s a selection of WaderTales blogs that may appeal to counters who contribute to the UK Wetland Bird Survey (WeBS) and other birdwatchers who like waders/shorebirds.

Blog RINGOS

It’s 70 years since UK birdwatchers started to count waders and waterfowl and there are now over 3000 registered Wetland Bird Survey volunteers.

WeBS70logo6a_smallThe work that volunteers do to chart the rises and falls of species as diverse as Redshanks and Whooper Swans provides a unique insight into the fortunes of our wintering waterbirds. As a tribute to the people behind the binoculars and telescopes, I highlight seven WaderTales articles that use WeBS data. Click on the links in bold if you want to read a particular story.

Curlew counts

curlew

WeBS counts for Curlew in Great Britain between 1974 and 2016

In the blog Is the Curlew really near-threatened? WeBS counts are used to show how numbers have changed over the decades. There might have been a boost in numbers when Curlew came off the hunting quarry list in Great Britain in 1981 but declines in the last 15 years reflect issues birds face in the breeding season in many parts of their European range.

Internationally, Eurasian Curlews are classified as near-threatened and in the UK they are now red listed. WeBS counts in Northern Ireland, alongside I-WeBS counts in the Republic, were successfully used to argue for the cessation of shooting across the island of Ireland in 2012.

Scottish Oystercatchers

L17A9623 (2)

Oystercatchers are unusual, amongst waders, in that they feed their young

Surely the Oystercatcher is one wader species that we don’t need to worry about? Although the blog Oystercatcher: from shingle beach to roof-top leads with nesting behaviour, WeBS counts are used to illustrate regional trends in different parts of the United Kingdom. In Scotland, there is concern about poor breeding success, while in parts of Wales and England, WeBS counts may provide a way of measuring the population-level effects of cockle fishing and diseases affecting shellfish.

oyc webs

Three very different trajectories for national WeBS counts for Oystercatchers since 1974

Mid-winter movements

figureThe annual WeBS report highlights the months in which counts are at their highest in different estuaries. For Knot, for instance, the highest counts on the Wash are in September, in other east-coast estuaries and on the Dee the peak is in December, whilst further north, in Morecambe Bay and the Solway, top numbers occur in January and February.

In Godwits & Godwiteers, which focuses on the superb work of observers who track the movements of colour-ringed Black-tailed Godwits, WeBS counts from east coast estuaries and the Ouse Washes illustrate the move inland that occurs as the winter progresses.

National patterns and local counts

blogGroups of WeBS counters who cover local estuaries will be the first to notice changes in the numbers of the key species that use their own sites. If the number of Dunlin drops, is that a local phenomenon or part of a national picture? Is there always a strong link between national declines (or increases) and site-based counts? Interpreting changing wader counts provides some answers. It emphasises just how reluctant waders are to change wintering sites between years.

High-tide roosts

horse-and-flockEvery WeBS counter will appreciate the value of a safe (undisturbed) roosting site, whether this be used by waders or by ducks and geese. In A place to roost, WeBS counts for Black-tailed Godwits are used to assess the national and international importance of an individual roosting site in northwest England. The main thread, however, is about the energy expenditure associated with sleeping (not very much) and travelling to and from a safe roost site (lots). An interesting add-on is the story of what happened to Cardiff’s Redshanks when the estuary was turned into a lake.

New recruits

If adult birds don’t change their winter homes then increases in local populations may well reflect good breeding years for wader species. 2017 was a good year for several species that breed in Iceland, particularly Black-tailed Godwits. T with BTGA great summer for Iceland’s waders puts the year’s productivity into context and gives an update on wader research that is being undertaken by the South Iceland Research Centre (University of Iceland), the University of East Anglia (UK) and the University of Aveiro (Portugal). If you have ever seen a colour-ringed Black-tailed Godwit, Ringed Plover, Oystercatcher or Whimbrel you may well find this interesting.

On the open shore

NEWS tableThe blog News & Oystercatchers was written to promote the Non-estuarine Waterbird Survey of 2015/16, or NEWS-III. There are a lot of waders on the shorelines that link the estuaries that are covered for WeBS and, every few years, volunteers are asked to count these birds. In NEWS-II (2006/07), it was estimated that 87% of Purple Sandpipers were to be found on the open shore (see table) with high numbers of several other species. There’s an initial assessment of the results for NEWS-III in the latest WeBS report and I look forward to writing up the results as a WaderTales blog, once a paper is published.

Links to blogs mentioned already

Many more to choose from

There are over 40 WaderTales blogs to choose from in this list. Four of these articles might be of particular interest to WeBS counters:

  • knot

    Knot migration

    Which wader, when and why? gives an overview of the migration of waders into, out of and through Britain & Ireland. The patterns help to explain why the peak numbers for Sanderling occur on the Wash in August, on the Dee in November and on the North Norfolk coast in May, for instance.

  • Bar-tailed Godwits: migration & survival  contrasts the different migration patterns of the two races of Bar-tailed Godwits that use British & Irish estuaries and explains the importance of colour-rings in the calculation of survival rates. On the other side of the world, Wader declines in the shrinking Yellow Sea shows how quickly numbers can change if the annual survival probabilities of adults fall. sum plum
  • The not-so-Grey Plover focuses on the Grey or Black-bellied Plover but the real story is about moult. British and Irish estuaries are important to huge numbers of moulting waders. WeBS counters often don’t have time to look at individual birds but, with the right camera, you can learn a lot about waders by checking out the right feathers.

Thank you

Blog Counter 1I use WeBS data a lot – in my blogs and in articles – and I appreciate the tremendous value of data collected each month by thousands of contributors. They monitor the condition of their local patches and have directly contributed to local, national and international reviews of the conservation status of wintering waterbirds. To every current and past WeBS counter – ‘thank you!’

There’s a (large) selection of papers using WeBS data here, on the BTO website. The Wetland Bird Survey is run by the BTO, in partnership with RSPB and JNCC (which acts on behalf of NE, NRW, SNH & DAERA), and in association with WWT.


 GFA in Iceland

WaderTales blogs are written by Graham Appleton, to celebrate waders and wader research.  Many of the articles are based on previously published papers, with the aim of making wader science available to a broader audience.

@grahamfappleton