Monthly Archives: April 2017

Kirkeuglen har stadig en chance i Danmark

kirkeugle KD 1(DOF 19 April 2017; Photo Klaus Dichmann)

Med flere redekasser og flere fritidslandbrug er der stadig håb for den truede kirkeugle i Danmark. Det vurderer tyske uglespecialister fra Landesverband Eulen-Schutz in Schleswig-Holstein, skriver bladet Fugle & Natur.

Der er næppe flere end 20 par kirkeugler tilbage i Danmark, og den lille charmerende ugle er flere gange erklæret dødsdømt som dansk ynglefugl. Men Dansk Ornitologisk Forening, DOF, har ikke opgivet:

– Hvis kirkeuglen vil forsvinde, så skal vi i hvert fald gøre det så besværligt for den, som vi overhovedet kan, som Klaus Dichmann, formand for DOF’s uglegruppe, udtrykker det med et glimt i øjet.

Han har fået lidt af optimismen tilbage efter et besøg fra tyske ugleeksperter sidste år. Tre ornitologer fra den tyske uglegruppe i Schleswig-Holstein besøgte de områder i Himmerland, hvor der stadig yngler måske 10-15 par kirkeugler.

Tyskerne kommer selv fra et område kun et halvt hundrede kilometer syd for grænsen, hvor der er en stabil bestand af kirkeugler på omkring 60 par. De konkluderer i deres rapport om besøget, at kirkeuglen stadig har en chance i Danmark, hvis der nu sker en målrettet opsætning af redekasser på de landejendomme, som egner sig til kirkeuglen.

– Der er ikke føde nok til kirkeuglerne i det effektivt drevne landbrug. Men også i Himmerland flytter flere mennesker fra byerne nu ud på landet i nedlagte landejendomme, hvor de starter fritidslandbrug med fritgående heste, får eller kødkvæg i indhegninger omkring gårdens bygninger. Det er præcis den form for landbrug, som giver et varieret fødegrundlag for kirkeuglerne, siger Klaus Dichmann.

Kirkeuglerne spiser store insekter, regnorme, mus, padder og småfugle, som de fanger på jorden. Undersøgelser viser, at de sidste danske kirkeugler især søger føde lige omkring de bygninger, hvor de yngler.

Styregruppen for ”Projekt Kirkeugle” i Himmerland er derfor i gang med at udpege velegnede ejendomme i nærheden af eksisterende uglepar. Hvis forholdene er uglevenlige og ejendommens ejere er indforstået, så sættes der kirkeuglekasser op, som forhåbentlig kan tiltrække unger fra uglepar i nærheden.

– Vi forventer at sætte mindst 20 kasser op i år på nøje udvalgte ejendomme, og der er flere på vej, siger Klaus Dichmann.

New report documents dramatic Antarctic penguin population loss

Hundreds of Adélie Penguins gather on Ross Island in Antarctica. Photo by David Grémillet

(Birdwatching Daily; 28 April 2017; Photo David Grémillet)

The inaugural “State of Antarctic Penguins” (SOAP) report, released on World Penguin Day (April 25) by international science-based NGO Oceanites, reveals that at least two species of Antarctic penguin — Adélie and Chinstrap — have suffered dramatic declines in population due to warming on the Antarctic peninsula. The SOAP report also identifies important trends about the keystone Antarctic penguin species — Adélie, Chinstrap, Emperor, and Gentoo — noting future concerns about these populations. Up-to-date data from more than 660 sites across the entire Antarctic continent has been aggregated and summarized for the report, including 3,176 records from 101 sources of on-the-ground colony counts and satellite photo analyses. The results are both significant and alarming, according to Oceanites founder and president Ron Naveen.

“In one generation, I have personally witnessed the precipitous decline of once abundant Adélie and Chinstrap Penguin populations,” said Naveen. “These iconic birds are literally canaries in the coal mine. They provide critical insights into the dramatic changes taking place in the Antarctic. What’s happening to penguin populations can have important implications for all of us.”

Critical scientific expertise for the SOAP report was provided by the Lynch Lab for Quantitative Ecology at Stony Brook University, who partnered with NASA to develop the Mapping Application for Penguin Populations and Projected Dynamics (MAPPPD), a unique open-ended scientific support tool intended to provide “one-stop shopping” for scientists studying penguin populations in the Antarctic.

Heather Lynch, associate professor and director of the Lynch Lab, states, “We can now use advanced satellite technology and data analyses to better understand how these penguin populations are changing. By integrating expert biological field surveys, satellite imagery analyses, and citizen science, we can further enhance our ability to understand the changes taking place in an incredibly important world we are just learning about.”

The SOAP report presents findings both continent-wide and per key Antarctic fishing areas designated by the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR).

Key report findings:

Over the past 60-plus years in the vastly warmed Antarctic Peninsula, Gentoo populations have increased significantly; Adélie Penguin populations have, in general, declined significantly; and Chinstrap Penguin populations have declined — at some locations significantly.

By contrast, in East Antarctica and the Ross Sea, regions that have not experienced a warming trend, Adélie Penguin populations appear to be increasing.

The SOAP 2017 report notes various concerns, all related to climate, potentially affecting these penguin populations — including the potential for ice sheet collapse both in West and East Antarctica.

Key implications:

In the vastly warmed Antarctic Peninsula, there are “winners” (rising numbers of Gentoos) and “losers” (decreasing numbers of Adélies and Chinstraps), foreboding concerns on whether humans will be able to adapt to warming trends.

Limiting warming to no more than 2°C / 3.6° F has become the de facto target for global climate policy; yet the Antarctic Peninsula already has warmed by more than that over the last 60 years — by 3°C / 5°F year-round and by 5°C / 9°F in the austral winter.

Ongoing studies are underway to ascertain whether penguins can maintain “the four vitals” necessary for adaptation and survival: food, habitat, health (disease-free environment), and reproduction (future generations).

Two species are in decline in the Antarctic Peninsula and another is adapting. Food might be an explanation; all the penguins can eat both krill and fish, but Gentoos, at this point in time, appear to have adapted better to reduced krill availability by eating more fish.

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

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(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.

Seabird parents compensate for struggling partners

(AOS 26 April 2017; Photo: L. Takahashi)

For species where both parents work together to raise their offspring, cooperation is key — it’s as true for birds as it is for us! A new study from The Auk: Ornithological Advances shows how pairs of Common Murres update each other on their condition so that when one partner needs a break, the other can pick up the slack.

Common Murre parents trade duties throughout the day — one stays at the nest while the other leaves to forage, hopefully coming back with a fish for the chick. Because brooding the chick requires much less energy than foraging, staying at the nest is preferable for a bird that’s in poor condition. Linda Takahashi, Anne Storey, and Carolyn Walsh of Newfoundland’s Memorial University, along with Sabina Wilhelm of the Canadian Wildlife Service, studied the “turn-taking ceremony” that parents perform when they switch places. They found that the time they spend preening each other provides a way for the two birds to exchange information about how they’re doing, so that if one is in poor shape the other can compensate.

The researchers observed 16 pairs of murres with chicks on an island off the coast of Newfoundland in summer 2009, recording their behavior when parents switched duties at the nest and capturing the birds to check their body condition. Their results show that these “nest relief” interactions take longer when one partner is especially low in body mass, suggesting that when brooders withhold preening and stall their departure, they’re letting their mates know that they need more time to rest; the returning mate can then compensate by going off to forage again rather than trading places immediately. Similarly, the brooding mate might let a struggling returner take over take over at the nest even if they haven’t brought back a fish.

“We had been doing murre field work for years in Witless Bay studying reproductive and parental behavior, and we became intrigued with the variation that we saw among pairs in their nest relief behaviors,” says Walsh. “Some nest reliefs were short and businesslike, while other nest reliefs seemed to involve a lot of interaction between the mates, and it took a long time for the mates to exchange brooding duty. When Linda Takahashi came to Memorial University as a master’s degree student, we decided that her project should focus on getting the details about this very interesting variation in murre nest relief behaviors.”

“The roles of avian pair members have been much studied in terms of energy investment and food delivery, but we are accustomed to thinking of these problems in terms of evolutionary tradeoffs. The ways in which contributions are actually negotiated within individual pairs has, until recently, been largely overlooked,” according to longtime seabird researcher Tony Gaston of Environment Canada. “Linda Takahashi’s paper addresses this deficiency, and this is a field which promises to open up additional avenues of research on within-pair communication.”

Wind, rain play key role in breeding patterns of migratory tree swallows

https://upload.wikimedia.org/wikipedia/commons/d/dc/7Z1E7819.jpg(Physorg, University of Colorado; Photo Wikipedia; 25 April 2017)

Wind and precipitation play a crucial role in advancing or delaying the breeding cycles of North American tree swallows, according to the results of a new University of Colorado Boulder-led study.

The research, which appears today in the journal Proceedings of the Royal Society B, sheds new light on how wet, windy weather can affect tree swallow nesting and underscores the importance of considering factors beyond temperature when examining how climate change might affect species’ biological niche.

Over the past decade and a half, the average egg hatching date for tree swallows—a common migratory bird species that winters in temperate southern climates before nesting in the spring at sites across North America, including the sub-Arctic regions covered in the study—has shifted earlier in the year by an average of six days. This change is similar to, but considerably greater than, changes seen in more southerly sites and until now has been believed to correlate with rising temperatures.

However, when CU Boulder researchers tested how swallow nesting data from two different Alaskan sites corresponded with both daily and seasonal climate indicators like the number of windy days, days with measureable precipitation and average daily temperature, they found that windiness (or lack thereof) had the most consistent correlation with swallow breeding patterns over time.

“We expected that temperature and precipitation would be much more strongly predictive than wind,” said Daniel Doak, a professor in CU Boulder’s Environmental Studies Program and the co-author of the new research. “The study demonstrates that fine-scale climate effects are important to consider when thinking about what’s going to affect a species.”

The study developed as a result of a CU Boulder undergraduate’s research efforts. Rachel Irons, then a junior in the Department of Ecology and Evolutionary Biology, received a UROP grant and worked with the Alaska Department of Fish and Game on a long-term tree swallow nesting study to fulfill her senior thesis requirements.

“Swallow phenology in Alaska is shifting at twice the rate of the continental U.S.,” said Irons, who is the lead author of the new paper. “I figured it was related to temperature, but I added in wind and precipitation measurements just to get the whole climate picture.”

The results showed that a long-term decline in windiness (and to a more variable extent, rain) in central Alaska over the past decade-plus correlated with the birds’ earlier breeding much more strongly than temperature, indicating that wet, windy spring weather that may have delayed egg laying in the past is now less of an impediment for the swallows.

The authors noted that while it is not necessarily surprising that wind and rain would affect an aerial foraging species like tree swallows, the findings emphasize the need to broaden the scope of consideration when making predictions about which climate mechanisms will influence population ecology.

“This shows that our initial intuitions are not always good about what’s going to impact these birds and their patterns,” said Doak.

Extinction risk for many species vastly underestimated, study suggests

(Columbia University; Photo: Adesh Shivkar; 25 April 2017)

A new study indicates that the number of plant and animal species at risk of extinction may be considerably higher than previously thought. A team of researchers, however, believe they’ve come up with a formula that will help paint a more accurate picture.

The study appears in the journal Biological Conservation.

The maps describing species’ geographic ranges, which are used by the International Union for Conservation of Nature (IUCN) to determine threat status, appear to systematically overestimate the size of the habitat in which species can thrive, said Don Melnick, senior investigator on the study and the Thomas Hunt Morgan Professor of Conservation Biology in the Department of Ecology, Evolution and Environmental Biology (E3B) at Columbia University.

“Concerned about this issue, we aimed to determine how far off those maps were. In doing so, we found there is an enormous amount of freely available data on many species around the world that can be employed to get a better picture of exactly how many species are truly under extreme threat. This picture, grim as it may be, is necessary if we are going to accurately plan the steps needed to stem those threats, locally and globally.”

Currently, IUCN makes use of species sightings reported by experts to draw boundaries reflecting the geographic range of a given species. From these maps, the IUCN develops its Red List, which assigns a threat status to wild species: Vulnerable, Endangered, or Critically Endangered. Though the accuracy of threat risk assigned to a species relies heavily on these maps, Melnick and his colleagues believe they almost always overestimate the actual distribution of a species by incorporating areas of unsuitable habitat. This overestimation of range size, in turn, leads to a significant overestimation of population size and therefore an underestimation of extinction risk.

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Every penguin, ranked: which species are we most at risk of losing?

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(Author: Alex Dale; Photo: Christopher Michel; 24 April 2017)

10 of the world’s 18 species of penguin are threatened with extinction. Discover where they live, and the threats they face, in this illustrated list of the world’s species

Beautiful. Inspiring. Under threat.

The first third of our Protect A Penguin campaign tagline is self-explanatory. Beautiful. Even if you’ve got a heart as hard as a cement mixer, the sight of an Emperor Penguin chick huddling against the cold, or a flash of the Little Penguin’s vibrant blue feathers, is guaranteed to make you melt into a pile of goo.

And as for Inspiring? Well, is there a creature on this planet that better represents survival against all odds than the penguin? Over the course of their existence, these remarkable birds have evolved numerous incredible adaptions that allow them to thrive in some of the world’s most challenging marine environments. They can drink seawater, survive in temperatures as low -60°C (-76°F), and they are amazingly agile swimmers. Many can swim faster than we can run.

But they are also Under threat. While the penguins are heavily adapted for their environments, it has taken them millions of years to evolve these features, and human impact is hitting the penguins’ environments too hard and too fast for them to cope. This is why over half of the world’s penguins are now in real danger of going extinct.

But which ones are we most in danger of losing?

That’s where BirdLife comes in. As the official assessors of the status of the world’s birds for the IUCN Red List, our science team is tasked with regularly reviewing all available data for every species, and allocating it a threat level accordingly, depending on criteria such as range, numbers and rate of decline. The seven threat levels are (in increasing order of seriousness): LEAST CONCERN, NEAR THREATENED, VULNERABLE, ENDANGERED, CRITICALLY ENDANGERED, EXTINCT IN THE WILD AND EXTINCT.

To find out more about the world’s 18 penguins, where they live and which ones are in most peril, read on. And don’t forget: you can help by donating to our global Protect A Penguin campaign

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