Tag Archives: human impact

Removing predators doesn’t guarantee bird safety

Removing predators doesn't guarantee bird safety
(University of Queensland; 11 May 2018)

Removing introduced predators might not provide greater protection of nesting birds in Australia’s temperate forests and woodlands, according to a new University of Queensland study.

UQ School of Biological Sciences researcher Graham Fulton’s review of 300 scientific papers on nest predation has found that getting rid of medium-sized predators might actually increase attacks from smaller predators.

“In Australia, the introduction of foxes and cats, along with the reduction in dingo numbers is thought to have adversely impacted a range of smaller animals,” he said.

Mr Fulton said areas where foxes were baited showed increased nesting success, but controlling fox numbers could increase the number of cats, which also target .

In turn, controlling cat numbers could empower smaller predators such as black rats or mice.

“But it’s not only predators which are to blame, humans are too,” he said.

“Birds such as currawongs, grey butcherbirds, Australian magpies and crows have increased their range and numbers as a result of the clearing of forest and woodlands.

“These same birds are known predators of nestlings and eggs.”

He said more research was needed to improve the understanding of interactions between birds, their predators, and their habitats.

The study is published in Pacific Conservation Biology

What’s the catch? The fate of Europe’s seabirds

seabird.jpg(Bruna Campos 14 August 2017; Photo David Grémillet )

Bruna Campos explains why a ‘sea change’ in policy is needed to protect thousands of Europe’s seabirds from the threat of incidental bycatch in fishing gears.

Uneasy lies the head that wears a crown”, Shakespeare famously wrote – and though the great playwright was reflecting upon the power of princes, at BirdLife these words turn our thoughts to the plight of petrels…and shearwaters, and the seabirds that together carry the unwanted crown anointing them the most threatened bird group in the world.

Marine biodiversity is facing enormous pressure from a wide range of human activities that lead to habitat destruction and pollution. And a huge part of the problem is seabird ‘bycatch’, with an estimated 200,000 seabirds accidentally caught and killed by commercial fishing hooks and nets each year. Many of Europe’s 82 seabird species are at risk, but some species seem to be far more susceptible than others – for example, Steller’s and Common Eider, Long-tailed duck and Velvet scoter are regularly caught in gillnets in the Baltic, while Northern Fulmar and Great shearwater are menaced by demersal longline fishing off the coast of Western Scotland, Ireland and France. It is particularly alarming that already threatened species are being put into further peril; such is the case for several seaduck species (in dramatic decline in recent years) and also for the Balearic shearwater – Europe’s most threatened seabird.

“…an estimated 200,000 seabirds [are] accidentally caught and killed by commercial fishing hooks and nets each year.

Out at sea, BirdLife’s conservation team and our ‘Seabird Task Force’ are working with fishermen to overcome practical challenges through pioneering technical innovation. Nonetheless, bycatch of seabirds – and also many marine mammals and sea turtles – continues despite existing EU regulations. Improvements are clearly needed here on dry land before we will see a sea change in our fisheries.

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How Much Should Major Polluters Pay? A Case Against DuPont Provides a Model

(Paul Greenberg 16 Aug 2017; Photo Greg Kahn)

A biologist traced mercury from a company spill to contamination in songbirds, and devised a new way to hold polluters financially accountable.

It was just another sweltering summer afternoon gathering blood samples from Shenandoah Valley birds when the news came in. The ornithologist Dan Cristol had been conducting a preliminary assessment funded by DuPont to determine to what degree the company’s pollution of the watershed might have affected the avian community. DuPont was facing potential legal action and had cautiously agreed to one summer of funding for a small team to gauge just how expensive fixing the damages might be. True to his nature, Cristol hadn’t been tentative in his research. He and his students had skulked into stream-bank kingfisher nests, cornered screech owls near bridges, and mist-netted dozens of species of songbirds. Using tiny needles, they’d extracted drops of bird blood before gently releasing their subjects back into the wild. Then they’d shipped their samples to a toxicology lab at Texas A&M, and watched as their funding dribbled away at a rate of $55 per analyzed sample.

Now as the sun blazed over the South River, a major tributary of the mighty Shenandoah, and waves of heat rose up from the newly mown hayfields, Cristol opened an email from the lab and read the first test results.

“Holy fucking shit,” one of the students cried out.

“I rechecked the numbers about five times to make sure,” Cristol recalls. “We were being funded by the responsible party, so I figured DuPont would look at what we’d found and say, ‘OK, thanks but no thanks, we’ve seen enough.’ I was worried that after this tantalizing glimpse we would not get to learn what was really going on. But to their credit, everyone just kept moving forward and letting us propose to answer each new question that arose.”

Cristol and his students had discovered that the DuPont mercury spill had penetrated much further into the avian food web than anyone had previously expected. Not only was mercury found in fish-eating raptors like osprey and eagles, but it was present in bluebirds that flitted far away from the contaminated South River; it was in surprisingly high levels in the feathers of the distinctly non-riverine Red-eyed Vireo whose song tells you to look-up way-up tree-top to find it; it was in scrappy Carolina Wrens, whirling Tree Swallows, and reclusive thrushes. Even in the diminutive Blue-gray Gnatcatcher that weighs in at a miniscule third of an ounce.

More importantly, the work had laid the foundation for a novel way to restore North American songbird populations that are declining throughout the country. For Cristol’s research has ultimately perfected a way of holding major polluters accountable for something as profound as it has long been intangible: a means to calculate and seek reparations for bird years lost.

“You couldn’t have a better site to test the effects of methylmercury,” Cristol told me as we stood on a bridge over the South River in the City of Waynesboro and stared southeast at a 177-acre chemical plant. For roughly 50 years this gray smudge of a facility, built into the green hillsides by DuPont in 1928, manufactured something called acetate fibers—which used mercury as a catalyst for the first 20 years of its operation.

DuPont to its credit has never strongly contested that it put significant amounts of mercury into the South River. Ever since mercury was detected in river sediment and floodplain soil around the plant in the 1970s, the corporation has been trying to figure out a way to put its pollution legacy behind it. For years DuPont funded a vaguely missioned “South River Science Team” where state officials and academics monitored mercury levels in fish, with the hope that concentrations would eventually go down. No such decrease was observed. Sampling continued to show levels in some fish higher than 4 parts per million—nearly four times that found in swordfish, which the FDA urges consumers to avoid because of high mercury levels. Nevertheless, officials representing the State of Virginia (technically the key plaintiff in these early proceedings) seemed at a loss as to what to do next.

“They had been completely bamboozled,” says Nancy Marks, a senior attorney for the nonprofit Natural Resources Defense Council’s litigation team. Under Marks’s direction NRDC filed an intention to sue DuPont in the early 2000s to move the issue forward from monitoring to mitigation. “[DuPont’s] remedy was to have a hundred year monitoring program. But we knew the mercury in the river was sky high. And DuPont was the only obvious source.” Unlike other American watersheds that have been host to numerous polluters, the Waynesboro DuPont plant is all the mercury-discharging industry the South River basin ever had. The bulk of the mercury in the ecosystem and any harm it may have caused birds is undeniably DuPont’s fault.

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Canary in a coal mine: Survey captures global picture of air pollution’s effects on birds

(University of Wisconsin-Madison, Physorg 11 August 2017; Photo: Jeff Miller)

Famously, the use of caged birds to alert miners to the invisible dangers of gases such as carbon monoxide gave rise to the cautionary metaphor “canary in a coal mine.”

But other than the fact that exposure to toxic gases in a confined space kills caged birds before affecting humans — providing a timely warning to miners — what do we know about the effects of air pollution on birds?

Not as much as you’d think, according to researchers from the University of Wisconsin-Madison.

“We know a lot about air pollution’s effects on human health, and we know a lot about the impacts of air pollution across ecosystems,” explains Tracey Holloway, a professor in UW-Madison’s Nelson Institute for Environmental Studies. “We were surprised to discover how little we know about how air pollution affects birds.”

Writing Aug. 11 in the journal Environmental Research Letters, Holloway, an expert on air quality, and her former graduate student Olivia Sanderfoot, sort through nearly 70 years of the scientific literature to assess the state of knowledge of how air pollution directly affects the health, well-being, reproductive success and diversity of birds. This work is part of Sanderfoot’s ongoing National Science Foundation Graduate Research Fellowship.

According to the Wisconsin team’s survey of the literature, only two field studies since 1950 have looked at any aspect of the health and ecological well-being of wild bird populations in the United States. Globally, there are only a handful of studies that assess the impact of direct exposure to air pollutants on bird health. Those encompass studies of just a few dozen bird species of the roughly 10,000 or so species of birds known worldwide.

Part of the problem, says Sanderfoot, are the many variables in play. Not only are studies of wild bird communities difficult to implement, but factors such as types and levels of air pollution, dynamic atmospheric conditions, species-specific responses, and the difficulty of teasing out direct versus indirect effects of air pollution can confound even the most basic efforts to assess how birds fare when exposed to chemicals in the air.

“There is a lot of work to be done in this area,” says Sanderfoot. “Air quality is an ever-changing problem across the globe. There’s a need to look at different types of air pollution and different species all over the world. We have a huge lack of understanding of the levels of pollution birds are exposed to.”

Gaps in our understanding, according to the new study, include air pollution’s effects on the avian respiratory system; toxic effects on birds, including elevated stress levels and immunosuppression; behavioral changes; and effects on reproductive success and demographics, such as changes in population density, species diversity and community composition.

Holloway, who leads the NASA Health and Air Quality Applied Sciences Team (a multi-institutional team of researchers that serves as a nexus for analyzing environmental data from a constellation of Earth-observing satellites), notes that studying the effects of air pollution on humans is comparatively easier to assess as hospital records and mortality data are readily available to scientists. Air pollution, in fact, is one of the leading and most direct environmental threats to human health, she says.

Something that makes birds potentially more vulnerable to atmospheric contaminants is the efficiency of the avian respiratory system.

“Birds breathe unidirectionally,” notes Sanderfoot. “They definitely breathe more efficiently than humans, and it has been hypothesized that because their respiratory system is so much more efficient than ours, they are going to more readily pick up air pollutants.”

The study is a springboard for new research, Sanderfoot and Holloway argue, and may be especially important given birds’ role as sentinel species in the environment.

“When you talk to bird ecologists, air pollution is not necessarily perceived as a high-level issue,” Holloway says. “Things like climate and landscape changes are at the top of their list in terms of population densities, species diversity, ecological stress. But we know that air pollution is a major risk to human health, and from our study we see pretty clearly that there is an impact on birds, too.”

Vadare försvunna från vindkraftpark

(SOF 11 augusti 2017)
Det påtalas ofta att effekter sällan kan utläsas av kontrollprogram som upprättas efter etablering av vindkraft. Det kan bl.a. bero på naturliga variationer i de (fågel-)bestånd som undersöks samt att synbara förändringar ibland uppstår med avsevärd fördröjning – eller så klart att vindkraftverken inte utgör någon påverkan.
Nu finns emellertid ett intressant exempel från Stor-Rotlidens vindkraftpark i Åsele kommun, Västerbottens län. Granholmsmyran, en myr som tidigare hyste ett vadarsamhälle, saknar mindre än tio år efter etableringen helt häckande vadarfåglar.
Vid basinventeringen 2009 räknades 11 ljungpipare, 4 grönbenor, 6 gluttsnäppor, 2 skogssnäppor samt enstaka exemplar av rödbena och storspov. Ett halvt decennium senare, 2014, hade vadarsamhället minskat till 4 grönbenor, 2 ljungpipare, 1 skogssnäppa samt 1 småspov. Ytterligare två år senare stod alltså inte en enda vadare att finna vid inventeringen.
Detta är givetvis en dramatisk utveckling och även om det inte är vetenskapligt belagt att vindkraftparken är det som har orsakat vadarnas försvinnande så finns det ingen annan uppenbar förklaring.
Det kan i sammanhanget nämnas att det 2016 publicerades ännu en undersökning som påvisade vadares känslighet för vindkraftsetablering. I den brittiska studien minskade antalet häckande ljungpipare med 79 % i anslutning till en vindkraftpark och undanträngningseffekterna var tydliga upp till 400 meter från verken (Sansom et al. 2016. Negative impact of wind energy development on a breeding shorebird assessed with a BACI study design. IBIS 158: 541–555)

Prairie-Chicken Nests Appear Unaffected by Wind Energy Facility

CONDOR-17-51 L Powell

(AOS 9 August; Photo: L. Powell)

Wind energy development in the Great Plains is increasing, spurring concern about its potential effects on grassland birds, the most rapidly declining avian group in North America. However, a new study from The Condor: Ornithological Applications suggests that for one grassland bird species of concern—the Greater Prairie-Chicken—wind energy infrastructure has little to no effect on nesting. Instead, roads and livestock grazing remain the most significant threats to its successful reproduction.

Prairie-chickens are thought to avoid tall structures such as wind turbines because they provide a perch from which raptors can hunt. To learn more, the University of Nebraska–Lincoln’s Jocelyn Olney Harrison and her colleagues gathered data on the effects of an existing small wind energy facility (36 turbines) in Nebraska. They captured 78 female prairie-chickens at breeding sites, or leks, ranging from less than a kilometer from the wind energy facility to more than twenty kilometers away, and fitted the birds with transmitters to track them to their nests. Monitoring their nesting success and collecting data on the habitat characteristics of each nest site, they found little evidence that the wind energy facility affected nest site selection or a nest’s chances of survival. Instead, vegetation characteristics, driven by land use practices such as grazing, had the greatest influence on prairie-chicken nests. Birds also avoided nesting near roads.

“When comparing previousw studies to our own, it appears that the effects of wind energy facilities on prairie grouse are often site- and species-specific,” says Harrison. “Therefore, it’s important to consider the results of our study in the context of the size and location of the wind energy facility, as well as the prairie grouse species investigated. We suggest that livestock grazing and other grassland management practices still have the most important regional effects on Greater Prairie-Chickens, but we caution future planners to account for potential negative effects of roads on nest site placement.”

Private landowners were key to completing the study, Harrison adds. “Our radio- and satellite-tagged Greater Prairie-Chickens made larger than expected movements while we were tracking them, which led us to require permission from new land owners on almost a weekly basis during our field seasons. Landowners throughout our field study area were always extremely welcoming and helpful, and genuinely interested in our work. Our project was a success due to more than 50 landowners who granted us access to their private lands.”

Uaktuelt med oljeboring utenfor Lofoten, Vesterålen og Senja

Norsk Ornitologisk Forening og Naturvernforbundet 1 augusti 2017; Foto Håvard Eggen)

Forslaget om oljeutvinning i Lofoten, Vesterålen og Senja vil medføre at olje- og gassindustrien rykker nærmere globalt viktige områder for sjøfugler. Oljeutslipp her vil være en katastrofe. I likhet med faglige instanser anerkjenner vi at risiko for utslipp er lav, men mener at naturverdiene er så store at området bør skjermes.

I fjor ble vi kjent med sjøfuglene på Hornøya i Finnmark gjennom NRKs direktesendte fjernsynssatsing, der vi kunne følge livet i fuglefjellet minutt for minutt. Mange ble kjent med fugler som alke, lunde og krykkje. Ingen andre steder i landet ligger sjøfuglområdene så tett som utenfor Lofoten og Vesterålen, til tross for et stadig vanskeligere liv for de fjærkledde. Det er de fantastisk produktive havområdene som har gjort det mulig for sjøfuglene å leve her. Og som perler på en snor ligger de enorme sjøfuglforekomstene på Røst, Værøy, Nykvåg, Anda og Bleik, områder som er pekt ut som fem av de viktigste for sjøfugler i Norge.

For nær store fugleforekomster

15 kilometer fra de antatte olje- og gassforekomstene utenfor Lofoten finner vi de største sjøfuglkoloniene på Røst. Historien til sjøfuglene våre er dessverre trist. Siden vi begynte å overvåke sjøfuglene på Røst i 1979 har tilbakegangen vært stor. Nå er kun en femtedel av lundebestanden igjen, mens antall ærfugler på Røst er redusert med 70 prosent siden 1988. Dette er en utvikling som vi ser for flere av våre sjøfugler langs norskekysten.

En av truslene mot sjøfuglene våre er klimaendringene. Når temperaturen i verdenshavene stiger, endrer også vandringsmønstrene for enkelte av fiskebestandene seg. De 300 000 lundeparene på Røst er avhengige av nær tilgang på småfisk som sild og tobis i hekketida. Det er paradoksalt når politikere er villig til å øke risikoen for sjøfuglene våre, og det dobbelt opp. Dersom området utenfor Lofoten blir åpnet for oljevirksomhet, vil vi utforske nye grenser for å produsere et produkt som skaper klimaendringer som truer sjøfuglene. I tillegg er sjøfuglene svært utsatt for eventuelle oljesøl.

Havområdene rundt Røst er også viktige overvintringsområder for tusenvis av ender som ærfugl, praktærfugl og havelle. Disse finner man i tette flokker. Selv små oljesøl vil ramme mange fugler. En situasjon med oljesøl i dårlig vær med høye bølger i de værharde områdene, vil være en håpløs oppgave å takle for norsk oljevernberedskap. Selv små mengder olje i fjærdrakten kan bety en sikker død. Ifølge en rapport fra Det Norske Veritas fra 2012 vil en oljeulykke i dette området kunne få katastrofale konsekvenser for sjøfuglene. Det kan ta mer enn 10 år før bestanden blir restituert, om den noen gang blir det.

Nå ser vi at flere av sjøfuglbestandene våre er i tilbakegang. Men det finnes fortsatt håp. Bestandene kan ta seg opp igjen når forholdene bedrer seg. Truede arter krever spesiell ivaretakelse. Betydningen av hvert individ øker i takt med hvor truet arten er, sett i et bestandsperspektiv. Ved Røst finner vi noen av de mest truede sjøfuglartene våre. Risikoen ved oljeutvinning nært sjøfuglforekomstene er altfor stor.

Færre trusler, ikke flere

Rundt 35 prosent av sjøfuglene våre har forsvunnet siden 2005. Det gir all grunn til å være bekymret. Da blir det så vanvittig at flere parter ønsker å gi disse utrydningstruede fugleartene nye trusler, i stedet for vern. NOF er klart imot å åpne Lofoten for petroleumsaktivitet, også utenfor Røst. Det gir oljeindustrien akkurat det de har mast om. Det gir ikke noe vern til de viktige fiskefeltene utenfor Røst. Det gir ikke noe vern til det området hvor våre viktigste kommersielle fiskearter gyter. Det gir ikke noe vern til verdens største kaldtvannskorallrev. Og sjøfuglene våre lever stadig farligere.

I løpet av det siste året har stadig flere støttet et oljefritt Lofoten, Vesterålen og Senja, både i meningsmålingene og ikke minst i kommunene i Lofoten. I 2011 var det kun én kommune som sa nei til oljevirksomhet i dette området, i dag er det ingen kommuner i Lofoten som sier ja til åpning. Utsiktene for lundene og de andre naboene i fuglefjellene ser kanskje ikke så lyse ut. Men de skal slippe å ha oljeindustrien enda nærmere fiskeområder og boplasser. For fisken og for sjøfuglenes del bør havområdene utenfor Lofoten og Vesterålen sikres varig vern fra petroleumsaktivitet.