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My school-aged kids and their friends are obsessed with poo. They talk about it, point it out on hikes, and try to decipher what the animal that made the deposit had eaten. They are little scatologists. Turning our attention to poo can tell us a lot about an animal, especially when one applies modern technology to the science of scatology. The fusion of animal droppings with molecular lab techniques is called molecular scatology, or polymerase chain reaction (PCR) on poo. In this issue of Wader Study, Novic, Veit, Mizrahi and Symondson apply molecular scatology to shorebirds on stopover during spring migration in Delaware Bay. In their article1, they describe how they collected fecal samples from shorebirds and performed amphipod specific PCR on these samples to figure out whether amphipods form part of the shorebird diet in Delaware Bay. Delaware Bay is known as a critical stopover site for shorebirds on spring migration and it is well known that the eggs of spawning Horseshoe Crabs Limulus polyphemus provide an essential food source. An earlier study2, conducted by the same researchers, focused on detecting Horseshoe Crab DNA in bird feces and confirmed the importance of Horseshoe Crab eggs for migrating shorebirds. But the eggs seemed more important for some species than others, making the researchers wonder about other invertebrate food sources for shorebirds in Delaware Bay. The amphipod Corophium volutator is a valuable prey item for shorebirds in the Bay of Fundy during fall stopover. Over 40 species of amphipod crustaceans have been reported in Delaware Bay, and the researchers wondered whether shorebirds were eating amphipods in the Bay. Understanding how shorebirds use all food resources at this critical stopover site will support more effective conservation and management. But why the fancy techniques, why not just look at the poo? Often shorebird biologists can figure out what the birds have been eating by looking closely at fecal samples. This is because some shorebirds, in some parts of the world, eat hard-shelled prey (like clams and mussels) whose shell fragments can still be identified in the feces. But in Delaware Bay, shorebirds are eating softer prey. Neither digested Horseshoe Crab eggs nor invertebrates like amphipods are easy to see in feces. Other methods, like flushing the stomach contents, are much more invasive, and small and soft prey is hard to see even then because shorebirds rapidly digest food. This is why molecular scatology is so useful. To perform molecular scatology, the researchers first needed to ensure that the PCR primers reliably detected the amphipods they were targeting. To do this – and also to examine seasonal change in abundance of invertebrates throughout the stopover season – they took benthic core samples within foraging areas on the New Jersey side of Delaware Bay. They found that their primers did indeed detect amphipod species. They also found that densities of amphipods in Delaware Bay were considerably lower than those of C. volutator in the Bay of Fundy, and that the maximum densities of amphipods in the study sites were substantially lower than the densities of Limulus eggs. But were the birds eating the amphipods (even though the eggs were more abundant)? And were the amphipods a more important food source for some species but not others? To find out, they needed to try their amphipod primers on poo. They caught shorebirds by mist-netting throughout May in both 2011 and 2012 and obtained fecal samples from individual birds by placing the birds in foil-lined boxes and collecting their droppings once they were deposited. As was the case with the benthic core samples, the primers successfully amplified amphipod DNA from the fecal samples. Amphipod DNA was present in samples from all four species tested: Dunlins, Least Sandpipers, Semipalmated Sandpipers and Short-billed Dowitchers. These species are eating amphipods, in addition to Horseshoe Crab eggs, during spring stopover in Delaware Bay. [caption id="attachment_8975" align="alignnone" width="670"] Dunlin (left) and Short-billed Dowitcher (right) are two of the species found to be eating amphipods as an alternative prey in Delaware Bay. Photos: D. Buehler.[/caption] In the 2012 data, they also found significant differences in occurrence of amphipods in feces of different species, with Least Sandpipers using this food sources more than Dunlins, Semipalmated Sandpipers and Short-billed Dowitchers. This is consistent with the Least Sandpiper tendency to forage in vegetated areas of tidal marshes where spawning crabs are uncommon. It is also consistent with the earlier finding that Limulus eggs were found in a smaller percentage of Least Sandpiper samples compared with other shorebird species2. It seems that Least Sandpipers rely on amphipods, and probably other benthic invertebrates, rather than Horseshoe Crab eggs during spring stopover in Delaware Bay. The researchers also note that amphipods may also be an important food source for other shorebird species before crab eggs become available in early spring. By blending old and new methods, the researchers gained a better understanding of how shorebirds use available resources at this critical stopover area. Such information is necessary for the effective conservation and management of both shorebirds and their foraging habitats. In Delaware Bay, we are learning that that tidal mudflats and marshes, where birds feed on various benthic invertebrates, are also important foraging habitats for shorebirds. Hence, new conservation strategies regarding these habitats should be considered in the future. This study is one of many in which researchers have incorporated new technologies into the study of birds. Other innovations include the use geolocators for everything from discovering the flight paths of long distance migrants to studying their breeding biology in remote areas (as highlighted by a [paper] by Lisovski and colleagues, also in this issue of Wader Study3. It is truly and exciting time for technology in the study of waders and other birds4.
  1. Novcic, I., R.R. Veit, D.S. Mizrahi & W.O.C. Symondson. 2016. Molecular analysis of amphipods in the diets of migrating shorebirds. Wader Study 123(3): 195-201.
  2. Novcic, I., D.S Mizrahi, R.R. Veit & W.O.C. Symondson. 2015. Molecular analysis of the value of Horseshoe Crab eggs to migrating shorebirds. Avian Biology Research 8: 210–220.
  3. Lisovski, S., K. Gosbell, C. Hassell & C. Minton. 2016. Tracking the full annual-cycle of Great Knot, Calidris tenuirostris, a long distance migratory shorebird of the East-Asian Australasian Flyway. Wader Study 123(3): 177-189.
  4. Altshuler, D.L., K. L. Cockle, & W. A. Boyle. 2013 North American ornithology in transition. Biol Lett 9: 20120876. http://rsbl.royalsocietypublishing.org/content/9/1/20120876
PDF version can be downloaded here.
Spotlight: Molecular Scatology – PCR on poo reveals wader diets

My school-aged kids and their friends are obsessed with poo. They talk about it, point it out on hikes, and try to decipher what the animal that made the deposit had eaten. They are little scatologists. Turning our attention to poo can tell us a lot about an animal, especially when one applies modern technology to the science of scatology. The fusion of animal droppings with molecular lab techniques is called molecular scatology, or polymerase chain reaction (PCR) on poo. In this issue of Wader

We received a number of strong applications for the 2016 IWSG Small Projects Grants, and after a careful consideration we are very pleased to inform you that, for its first year, the grant will support the project proposal of Glenda D. Hevia & Verónica L. D’Amico on the impact of human activities on Two-Banded Plovers (Charadrius falklandicus) breeding at beaches in Northern Patagonia, Argentina. Glenda Hevia is conducting PhD research on the impact of human disturbance on reproductive success, blood parameters and physical condition of the Two-Banded Plover (Charadrius falklandicus) during their breeding season in northern Patagonia. She is supervised by Verónica L. D’Amico at the Centro para el Estudio de Sistemas Marinos, Centro Nacional Patagónico (CESIMAR – CCT CONICET – CENPAT). More details can be found on the IWSG Small Projects Grants page: http://www.waderstudygroup.org/projects/iwsg-small-projects-grants-apply-now/ You can follow the study at this ResearchGate Project page!: https://www.researchgate.net/project/Effects-of-human-activities-on-the-Two-banded-Plover-Charadrius-falklandicus-breeding-population-in-northern-Chubut-Patagonia-Argentina And on facebook: https://www.facebook.com/ChorloDobleCollar/ [caption id="attachment_8912" align="aligncenter" width="330"] ©Darío Podestá. Glenda D. Hevia collecting data from Two-Banded Plover nests during fieldwork at Península Valdés, Patagonia Argentina.[/caption] We wish Glenda and Verónica every success with their fieldwork and research! The call for the 2017 grants will open in the Spring.   Photo: ©Darío Podestá. Two-Banded Plover adult breeder incubating a nest in Cerro Avanzado beach near Puerto Madryn city, Chubut, Patagonia Argentina.
And the 2016 IWSG Small Grant Winner is….

We received a number of strong applications for the 2016 IWSG Small Projects Grants, and after a careful consideration we are very pleased to inform you that, for its first year, the grant will support the project proposal of Glenda D. Hevia & Verónica L. D’Amico on the impact of human activities on Two-Banded Plovers (Charadrius falklandicus) breeding at beaches in Northern Patagonia, Argentina. Glenda Hevia is conducting PhD research on the impact of human disturbance on reproductive

Check out this amazing site by Sławomir Popek & Mirosław Żarek! The picture says more than a thousand word. Browse the site here: www.shorebirds.pl or get in touch at info@shorebirds.pl.
Hand-carved wooden shorebirds from Poland

Check out this amazing site by Sławomir Popek & Mirosław Żarek! The picture says more than a thousand word. Browse the site here: www.shorebirds.pl or get in touch at info@shorebirds.pl.

Though retrieving of four of ten tagged Icelandic whimbrels fitted with geolocators, Jose Alves and their team investigated their non-stop flights between Iceland and West Africa and how wind support encountered en route affects flight speed. Tracks revealed that these birds could fly non-stop in two long-distance flights achieving very fast speeds (18–24 m s−1 depending of wind conditions) and flying over open waters, both in Spring and Autumn migration, even when an a mostly overland route of similar distance is available. Article “Very rapid long-distance sea crossing by a migratory bird”, published in Scientific Reports: http://www.nature.com/articles/srep38154 Photo: An Icelandic Whimbrel (Numenius phaeopus) © Tómas Gunnarsson [caption id="attachment_8831" align="aligncenter" width="330"]Icelandic whimbrel carrying a geolocator attached to a leg flag. © Verónica Mendez Icelandic whimbrel carrying a geolocator attached to a leg flag. © Verónica Mendez[/caption]
Tracks of Icelandic Eurasian Whimbrel reveals non-stop flights over the Atlantic ocean

Though retrieving of four of ten tagged Icelandic whimbrels fitted with geolocators, Jose Alves and their team investigated their non-stop flights between Iceland and West Africa and how wind support encountered en route affects flight speed. Tracks revealed that these birds could fly non-stop in two long-distance flights achieving very fast speeds (18–24 m s−1 depending of wind conditions) and flying over open waters, both in Spring and Autumn migration, even when an a mostly overland

Martin Bulla with the contribution of 76 co-authors has compiled an impressive incubation dataset of 729 nests of 91 populations of 32 species of shorebirds worldwide. As well as revealing the amazing variability in incubation rhythms of wild shorebirds, they also identified that this variability would be mostly driven by predation risk and not the starvation risk: Article “Unexpected diversity in socially synchronized rhythms of shorebirds”, published in Nature: http://www.nature.com/nature/journal/v540/n7631/full/nature20563.html Photo: An American Golden Plover (Pluvialis dominica) - from Barrow, Alaska – is sitting on its eggs.  © Joël Bêty More videos at: https://www.youtube.com/channel/UCP8ITIDaFZHW68z7KaTyDew [caption id="attachment_8814" align="aligncenter" width="330"]Actogram_1 - Martin bulla et al (2016) in Nature The figure shows 15 different patterns for each parent's time on the nest over 48 hours — females are depicted in yellow and males are in blue-grey. Incubation bouts ranged from less than three hours to up to 48 hours. © Martin Bulla in Nature.[/caption]
Variability in shorebird incubation patterns – Nature paper

Martin Bulla with the contribution of 76 co-authors has compiled an impressive incubation dataset of 729 nests of 91 populations of 32 species of shorebirds worldwide. As well as revealing the amazing variability in incubation rhythms of wild shorebirds, they also identified that this variability would be mostly driven by predation risk and not the starvation risk: Article “Unexpected diversity in socially synchronized rhythms of shorebirds”, published in Nature:

The printed version of the September issue of Wader Study must have appeared in your mail box by now. When you're done reading you can move on to new Early Online content of Wader Study 123-3. Check this page Waderstudy volume 123 issue 3. Juvenile sanderling
Keep an eye on the Early Online content of Wader Study

The printed version of the September issue of Wader Study must have appeared in your mail box by now. When you're done reading you can move on to new Early Online content of Wader Study 123-3. Check this page Waderstudy volume 123 issue 3.

WaderTales explains a study aiming to create the right habitats for adult Whimbrel, and for their chicks who have quite different requirements. Read full blog here. Further reading about the threatened Whimbrel and allies in in older Wader Tales can be found here.  
WaderTales: Establishing breeding requirements of Whimbrel

WaderTales explains a study aiming to create the right habitats for adult Whimbrel, and for their chicks who have quite different requirements. Read full blog here. Further reading about the threatened Whimbrel and allies in in older Wader Tales can be found here.  

jane-goodall-and-shorebirds-english
and in honour of this year’s world shorebird day, we present….

The WHSRN Hemispheric Council voted unanimously to approve the nomination of the Flint Hills as a WHSRN Landscape of Hemispheric Importance. This unique, 1.5-million-hectare tallgrass prairie landscape, spanning the U.S. states of Kansas and Oklahoma, annually supports more than 30% of the global population of Buff-breasted Sandpiper (Calidris subruficollis).  Read more here.  
WHSRNews Update: New WHSRN Landscape

The WHSRN Hemispheric Council voted unanimously to approve the nomination of the Flint Hills as a WHSRN Landscape of Hemispheric Importance. This unique, 1.5-million-hectare tallgrass prairie landscape, spanning the U.S. states of Kansas and Oklahoma, annually supports more than 30% of the global population of Buff-breasted Sandpiper (Calidris subruficollis). 

‘Moderation’: What does this simple word have to do with waders? Perhaps nothing at all, though it might help to explain some intriguing facts. For example, in their article in this issue of Wader Study1, Mischenko and Sukhanova report on rapidly decreasing population trends in farmland breeding waders in the Vinagradovo Floodplain near Moscow, Russia. The population declines in Russia are much like those seen in Western Europe, where farming intensification is a problem, but in the Vinagradovo Floodplain agriculture is not intensifying; indeed the opposite is true: farmlands are being abandoned. [caption id="attachment_8688" align="alignnone" width="700"]Male Black-tailed Godwit in abandoned hay meadow on the Vinogradovo Floodplain, Russia (photo: Alexander Mischenko). Male Black-tailed Godwit in abandoned hay meadow on the Vinogradovo Floodplain, Russia (photo: Alexander Mischenko).[/caption] Perhaps moderation is in order? Most likely this is too simplistic. Clearly the population health of breeding birds depends not only on factors within the breeding areas, but also on factors in other parts of the world and other times in the annual cycle. But let’s focus on the idea of moderation on the breeding grounds for a moment. Mischenko and Sukhanova give us an idea of what is happening in the Vinagradovo floodplain where they find that a strong reduction in low-intensity traditional farming and a decrease in the strength of floods are the main factors influencing a decrease in wader abundance. Agricultural activities in Vinogradovo Floodplain were drastically reduced between 1986 and 2000. Agriculture was heavily subsidized during the era of the Soviet Union. When the Union and these subsidies collapsed, farmland was abandoned across the country. In the early 1980s, haymaking, cattle grazing and the cultivation of maize, potatoes and other vegetables were common in the Vinogradovo Floodplain. These meadows and croplands flooded in spring and the resulting bare ground was used for nesting by waders. By the early 2000s grazing and crop production had ceased and today even land used for haymaking has decreased from 46% in the 1980s to 4–17% in 2010–2014. Without cattle and haymaking to keep the vegetation low, abandoned hay meadows and pastures are now full of dense grass and shrubs that are unsuitable for wader nesting. To make matters worse, these overgrown lands are also regularly burned between the end of April and the first week of May. [caption id="attachment_8689" align="alignnone" width="700"]Spring burning of abandoned farmlands on the Vinogradovo Floodplain, Russia, is a serious threat to nesting waders (photo: Alexander Mischenko). Spring burning of abandoned farmlands on the Vinogradovo Floodplain, Russia, is a serious threat to nesting waders (photo: Alexander Mischenko).[/caption] To examine seasonal flooding, the authors collected data from a hydrological station on the Moskva River and generated an index of flood intensity. They examined these data for each year during 1982–1985, 1995–1996 and 2002–2014 and categorized each year as having strong or weak flooding. They found that the height of spring flooding has decreased from the 1980s to the 2000s. Lower and shorter floods indicate a shift towards a drier and warmer climate in the area, a decrease in the area of temporarily flooded land, and hence a decrease in the preferred habitat of breeding and foraging waders. To study the effect of these changes on wader numbers, Mischenko and Sukhanova studied the abundance and distribution of waders using counts of territorial pairs within the floodplain (ca. 50 km²). They counted birds from the end of April to the beginning of June each year from 2002 to 2014. They then compared these data with published survey data for the study area taken in the early 1980s and during 1995–1996. The populations of several species of breeding wader decreased during the period of agricultural cessation and reduced flooding. Terek Sandpipers disappeared altogether, along with their preferred habitat of wet plough-lands. Ruffs, Northern Lapwings and Black-tailed Godwits also declined, as the short vegetation they prefer was no longer maintained by grazing and late-season haymaking. On the other hand, Marsh Sandpiper and Great Snipe numbers remained stable, and Common Snipe numbers have even increased a little since the 1980s. Some species were able to use short-term responses to capitalize on open habitats when they existed. For example, Great Snipes established temporary leks in years and areas where flooding created suitable habitats, and Black-tailed Godwits made use of open habitats created when floods matted down the otherwise tall vegetation. These rapid adjustments allowed species to continue to persist in the study area despite significant habitat change. However in the longer term, the authors suggest that agro-environment schemes that focus on traditional farming activities in the floodplain will be needed for the conservation of breeding waders. Changes in farming in Russia led to the northward expansion of several wader species including Black-tailed Godwit, Redshank, Marsh Sandpiper, and Northern Lapwing2. Waders began to colonize Russian farmland between the 1950s and the 1970s — a time of intense agricultural development. For example, lapwings bred in bogs and were very rare in farmland even at the beginning of the 20th century, but they are now one of the most common farmland birds in Russia. But even as waders colonized farmland, it was clear that not all aspects of farming were good for them — and intensive farming is deadly. Waders can be killed and their nests destroyed by mechanical cultivation, early spring harvesting and early hay harvesting. And even though a moderate amount of cattle grazing is required to keep vegetation at optimum heights for waders, cattle often trample nests. Finally, intensive agriculture requires chemical pesticides, herbicides and fertilizers, which are toxic to adult birds, chicks, and humans. It comes back to this idea of moderation. In a recent study of farmland bird communities in NW Russia3, Herzon and colleagues surveyed birds in a 450 km² agricultural landscape near St. Petersburg. They compared breeding densities of farmland bird species among different agricultural uses from May to July in 2005, 2006, 2008, 2010 and 2011. They found that pastures, multispecies grasslands and abandoned fields were particularly valuable habitats for farmland birds (of all types, not just waders). They recommended using grasslands for non-intensive haymaking and pasturing, retention of some of the abandoned fields as open fallows, and production of certain cereals as a nature-friendly way to increase agricultural production in the region. Thus, in NW Russia a mix of non-intensive agricultural land-uses is recommended for farmland birds, in W Europe farmland breeding waders are suffering under agricultural intensification, and on the Vinogradovo Floodplain waders are suffering under agricultural abandonment. Taken together this suggests that moderate farming might be a good thing for waders and for biodiversity in general. Tscharntke and others discuss this idea in a review paper in which they examine land sparing (where land for nature and land for agriculture are segregated and production is intense in agricultural areas) versus land sharing (wildlife-friendly farming)4. Clearly land sharing should not happen everywhere. Wild lands must be preserved, as untouched by humans as possible, for those species that cannot tolerate even the most wildlife-friendly human use. But where agriculture does take place, a system of land sharing practiced under non-intensive small landowner farming seems to be the most nature-friendly option. Such a scheme would also nurture the biodiversity that exists within agricultural systems and recognize that this biodiversity functionally supports the agriculture itself (through pollination, pest control, soil fertility, etc.). Moderation certainly won’t fix everything. Wader population trends depend on a multitude of factors: the climate, what habitats the birds originally needed and whether farming helps to create these, and myriad factors that affect the birds when not on their breeding grounds. Still, the idea of moderation in all things, or finding the middle ground between excess and deficiency5, might provide insight. This insight, coupled with more careful study, might allow us to find a true middle ground. Of course, this middle ground will differ from place to place and species to species, but working close to this middle ground might make things more sustainable for birds and humans alike. _________________________________________ Deborah M. Buehler Outreach Editor, ‘Wader Study’
  1. Mischenko , A. L & O. V. Sukhanova. 2016. Response of wader populations in the Vinogradovo Floodplain (Moscow Region, Russia) to changes in agricultural land use and spring flooding. Wader Study 123(2): 136-142.
  2. Lebedeva, E. A. 1998. Waders in agricultural habitats of European Russia. International Wader Studies 10: 315–324 (and references therein).
  3. Herzon, I., R. Marja, S. Menshikova, & A. Kondratyev. 2014. Farmland bird communities in an agricultural landscape in Northwest Russia: Seasonal and spatial patterns. Agriculture, Ecosystems and Environment 183: 78–85.
  4. Tscharntke, T., Y. Clough, T.C. Wanger, L. Jackson, I. Motzke, I. Perfecto, J. Vandermeer & A. Whitbread. 2012. Global food security, biodiversity conservation and the future of agricultural intensification. Biological Conservation 151(1): 53–59.
  5. Moderation in all things, or finding the mean, or middle ground, between excess and deficiency (extrapolation of Aristotle's Doctrine of the Mean (see https://ethicsinpr.wikispaces.com/Doctrine+of+the+Mean for a summary).
PDF version can be downloaded here.
Spotlight: Cessation? Intensification? Maybe moderation? What is best for farmland waders?

‘Moderation’: What does this simple word have to do with waders? Perhaps nothing at all, though it might help to explain some intriguing facts. For example, in their article in this issue of Wader Study1, Mischenko and Sukhanova report on rapidly decreasing population trends in farmland breeding waders in the Vinagradovo Floodplain near Moscow, Russia. The population declines in Russia are much like those seen in Western Europe, where farming intensification is a problem, but in the