Tag Archives: shorebirds

Højvande gav massedød blandt Vadehavets ynglefugle

 

En nyklækket havterne overlever ikke et højvande foto Jan Skriver WEB

(Jan Skriver 9 juni 2017)

Terner og vadefugle i hundredvis mistede æg og unger, da et ekstremt højvande natten mellem onsdag og torsdag oversvømmede Vadehavets kystnære kolonier. Det gik blandt andet ud over Danmarks største bestand af sjældne hvidbrystede præstekraver og truede dværgterner. Voldsom færdsel af turister tvinger fuglene længere ud, så de bliver mere udsatte for højvande. Men fuglene bør beskyttes bedre, mener ornitolog fra Fanø.

En storm og en ekstrem høj vandstand natten mellem onsdag og torsdag i denne uge har forårsaget ragnarok og massedød blandt flere af Vadehavets og marskens sårbare fuglearter.

Det er gået hårdt ud over havterner, dværgterner, klyder, strandskader og navnlig de hvidbrystede præstekraver, der har deres absolut vigtigste danske ynglepladser på Rømø og Fanø.

– Højvandet var ekstremt, og der er formentlig tale om den højeste vandstand, vi har set i vadehavsregionen på denne tid af året i 40-50 år. For de fuglearter, der yngler udenfor digerne, på strandene og højsanderne, har ødelæggelsen været total. Hundreder af havterner, dværgterner og klyder fik i løbet af nattens højvande, der kulminerede ved 2-tiden, deres reder med æg eller unger oversvømmet, siger ornitolog og naturvejleder, Kim Fischer, fra DOF Sydvestjylland.

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Breeding pairs of birds cooperate to resist climate change

(Physorg 5 June ; Photo: Juan. A. Amat )

Most bird chicks need parental care to survive. In biparental species the chicks have greater chances of success if both parents participate in this task, especially under hostile situations. An international team of scientists has revealed that when temperatures rise, males and females in pairs of plovers shift incubation more frequently.

Climate change causes ecological variation and affects the lives of animals. The ever-earlier springs and later autumns caused by rising temperatures cause changes to animals’ physiology, breeding seasons and even population distributions. However, little is still known about how animals behave in response to these disturbances.

A team of scientists, working in collaboration with the Doñana Biological Station (EBD-CSIC), has studied the influence of climate change on incubation in plovers (Charadrius spp.), a genus of shorebirds spread over six continents, with a total of 33 species.

Many plover species nest on the ground in sites where there is no plant cover to detect more easily approaching predators, but where their nests receive direct sunlight.

“This can represent a significant challenge,” as indicated to SINC by Juan A. Amat, a researcher at the EBD and one of the authors of the study, which was published recently in the journal Global Ecology and Biogeography.

The scientist adds that the situation can become complicated for birds in the middle of the day, “when incubating adults may not be able to tolerate the high temperatures.” Typically, the optimum temperature adults provide for embryonic development is 35-39 ºC.

“In many bird species where both mates participate in incubation, one sex, generally the female, incubates by day, while the other (the male) does it by night,” Amat explains. However, under hot conditions greater cooperation would be needed between males and females.

Males participate in daytime incubation

One solution under changing climates would be to shorten the duration of incubation shifts between the sexes. The paper, which was led by the University of Bath (United Kingdom), analysed the behaviour of 36 populations of 12 plover species. Its results reveal that male plovers assist the females during daytime incubation.

“Males’ participation in daytime incubation increases both with ambient temperature and with as the variability of maximum temperatures during the incubation period,” the expert stresses.

The research demonstrates that a rise in temperature changes these bird pairs’ behaviour and their daily routine in terms of nest attendance. “This flexibility of parental cooperation would facilitate responses to the impact of climate change on populations’ reproductive biology,” explains Amat, who considers that the reason behind the male’s increased help is the need to better protect the embryos from extreme conditions.

Previous studies have confirmed that environmental instability has an influence on the early stage of reproduction and the lives of birds, and that unpredictable variations in the environment also affect how bird pairs cooperate in caring for their offspring. The conclusion of this new paper is that climate variations strongly influence parental cooperation.

45% of Arctic shorebirds are disappearing – here’s the plan to save them

western-sandpiper-calidris-mauri.jpg

(Pacific Shorebirds 21 April 2017; Photo: Glenn Bartley)

Across the globe, 45% of Arctic-nesting shorebirds are decreasing. The Pacific Americas Shorebird Conservation Strategy aims to identify the threats and develop strategies to save them.

Shorebirds—plovers, oystercatchers, sandpipers, godwits, curlews—can be found along the entirety of the Pacific coast of the Western Hemisphere during some time of the year.

Many species travel from Arctic breeding areas to spend their winter on the beaches and mudflats of North America, Central America and South America, where they share the environment with resident species.

Whether migrants or residents, shorebirds and the habitats they depend upon are exposed to an increasing myriad of anthropogenic threats. Within the Pacific Flyway, 11% of shorebird populations face long-term declines; none are known to be increasing.

Although the challenges are great, they are not without solutions. Across the Western Hemisphere, shorebird scientists, conservationists and managers have come together to tackle the conservation issues across the annual life cycle of this incredible group of birds.

Although there is no doubt that successful conservation depends upon actions initiated locally, isolated interventions will have the best chance for positively affecting populations if coordinated at a flyway scale.

The Strategy follows a logical sequence of setting shorebird conservation targets, identifying major threats and identifying highly effective actions to restore and maintain shorebird populations throughout the Pacific Americas Flyway.

The Strategy is being lead by an international group of more than 85 experts in 15 countries, including BirdLife and some of its Partners.

The intent is to assemble and synthesize information to present a comprehensive approach and to address the most pressing conservation needs in the flyway from Alaska to Patagonia, while considering the human communities that interact with shorebirds. Only with investments in the portfolio of strategies and actions will conservation of this extraordinary group of birds be achieved.

The strategy is not a step-by-step recipe for conservation success but rather a framework for ceaseless collaboration, innovation and accomplishment.

Extensive partner involvement in the development of the Pacific Americas Shorebird Conservation Strategy will need to be sustained and augmented to achieve success across the flyway and to mold the broad strategies presented here into tangible, spatially explicit actions.

A well-coordinated, collective effort will be needed to achieve overall strategy success; thus, people, and transparent communication among them, are crucial for success.

Readers are encouraged to engage with the strategy’s partners to endeavor to sustain shorebird populations along the Pacific Americas Flyway well into the future.

Citizen scientists help identify shorebird extinction threat

(University of Queensland; 13 April 2017)

An international team of citizen scientists and researchers has identified a major contributor to the dramatic decline of migratory shorebird populations in Australia.

University of Queensland School of Biological Sciences researcher Associate Professor Richard Fuller said Australian shorebirds were under threat due to the degradation and destruction of mudflats thousands of kilometres away in north-east Asia.

Associate Professor Fuller was part of a team of researchers who worked on a shorebird study led by the University of Maryland’s Assistant Professor Dr Colin Studds.

Dr Studds said a critical factor in the decline of migratory shorebirds was their dependence on mudflats in the Yellow Sea, between China and South Korea.

“The more a species relies on the disappearing Yellow Sea mudflats, the faster they are declining,” Dr Studds said.

He said birds including species of godwit, curlew and sandpiper were under threat.

Many birds follow the East Asian Australasian Flyway migratory path from their non-breeding grounds in Australia to breeding sites in the Arctic, resting and refueling in the Yellow Sea.

“Scientists have long believed that loss of these rest stops could be related to the declines, but there was no smoking gun,” Dr Studds said.

The researchers analysed citizen science data collected between 1993 and 2012 on 10 key species, and what they found was dramatic.

Even though the birds only spend one or two months of the year at the mudflats, it was the most important factor in determining the population trend.

Associate Professor Fuller said the study was founded on decades of bird counting effort by volunteers across Australia and New Zealand.

“Without this effort, the study would have been impossible,” he said.

Australia has signed agreements with China, Korea and Japan to protect migratory birds, yet the birds have continued to decline.

“Every country along the migration route of these birds must protect habitat and reduce hunting to prevent the birds declining further or even going extinct,” Associate Professor Fuller said.

“We are particularly excited that China and Korea have recently begun the process of listing parts of the Yellow Sea as World Heritage Sites.”

Sandpiper detectives pinpoint trouble spots in continent-wide migration

Sandpiper detectives pinpoint trouble spots in continent-wide migration

(Physorg; 5 April 2017)

Understanding and managing migratory animal populations requires knowing what’s going on with them during all stages of their annual cycle—and how those stages affect each other. The annual cycle can be especially difficult to study for species that breed in the Arctic and winter in South America. A new study from The Condor: Ornithological Applications tackles this problem for Semipalmated Sandpipers, historically one of the most widespread and numerous shorebird species of the Western Hemisphere, whose populations in some areas have undergone mysterious declines in recent years.

Stephen Brown, Vice President of Shorebird Conservation for Manomet, assembled a large group of partner organizations to deploy 250 geolocators, tiny devices that use light levels to determine birds’ locations, on adult sandpipers at sites across their breeding range in the North American Arctic. Recapturing 59 of the birds after a year to download their data, they found that the eastern and western breeding populations use separate wintering areas and migration routes. Birds that breed in the eastern Arctic overwinter in areas of South America where large declines have been observed. The researchers believe these declines are tied to hunting on the wintering grounds and habitat alteration at migration stopover sites, although their precise impacts remain unclear.

“This study was a response to the discovery of a large decline in the population of Semipalmated Sandpipers in the core of their wintering area in South America, and the need to determine which birds were involved. We didn’t know if the decline affected the entire population or just part of it,” says Brown. “Bringing together the 18 partner organizations that worked collaboratively on this project allowed us to track the migration pathways used by Semipalmated Sandpipers at the enormous geographical scale of their entire North American Arctic breeding range and provided critical new information about what sites are important to protect to support their recovery.”

“The authors here present one of the few studies that examine year-round connectivity, including stopover sites, of Arctic-breeding shorebirds,” according to the University of Guelph’s Ryan Norris, an expert on migration tracking who was not involved with the study. “Multi-site, range-wide studies on connectivity, such as this, are critical if we are to understand the population consequences of environmental change in migratory birds.”

High Mercury Levels Pose Another Setback for Arctic Birds

(Katie Valentine, July 22, 2016)
Gone unchecked, the element can lead to sickness, sterility, or even death in breeding shorebirds.

Life in the Arctic has its challenges. The shorebirds that breed there each summer have to complete some of the longest migrations on record. Once they arrive, they’re forced to deal with harsh living and foraging conditions—made worse by the ill effects of a changing climate.

Now scientists are adding another hardship to the list: mercury poisoning. A new study by researchers at McGill University and the U.S. Fish and Wildlife Service shows that Arctic shorebirds are exhibiting high levels of mercury, which could be dangerous for their population numbers. “The concentrations in some were much higher than we would have ever expected for small birds that are foraging on insects,” says Marie Perkins, a PhD candidate at McGill and lead author of the study.

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Arctic-Breeding Shorebird Populations Are Plummeting, with No Single Culprit

(Margaret Munro, 06 January 2017)
There are almost 30 species of shorebirds that breed in the Canadian Arctic, and all are strongly migratory. Surely the longest of their migrations must count among the most impressive feats in the natural world. Red Knots, for instance, are only nine inches long. And yet, every year, they fly some 9,000 miles from their summertime Arctic nesting territories to their South American vacation hideaways—and then another 9,000 miles back again.

Unfortunately, shorebird population are hurting across the globe. In North America alone, shorebird populations have plummeted by 70 percent since 1973, and among those, birds that breed in the Arctic are especially threatened, writes journalist Margaret Munro in a recent Nature feature. But a workable solution is hard to come by because the birds face a multitude of threats as they make their way across the Western Hemisphere.

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