ScienceDaily (Feb. 21, 2012) — A small population of rattlesnakes that already is in decline in southern Illinois faces a new and unexpected threat in the form of a fungus rarely seen in the wild, researchers report.
The eastern massasauga rattlesnake (Sistrurus catenatus catenatus), a candidate for protection under the federal Endangered Species Act, suffers from habitat loss and environmental stresses wherever it is found, said University of Illinois comparative biosciences visiting instructor and wildlife veterinarian Matthew Allender, who led the health investigation. Long-term population studies of the snake -- in Illinois and elsewhere -- had never turned up evidence of debilitating fungal infections. But in 2008, biologists studying the snake reported to Allender that they had found three sick snakes in a park in southern Illinois, all with disfiguring lesions on their heads. The snakes died within three weeks of their discovery. A fourth snake with a similar syndrome was discovered in the same park in the spring of 2010.
Read on: http://www.sciencedaily.com/releases/2012/02/120221151543.htm
Showing posts with label decline in numbers. Show all posts
Showing posts with label decline in numbers. Show all posts
Thursday, February 23, 2012
Tuesday, February 21, 2012
Sea lion test to probe declines
Canadian researchers have trained sea lions to take part in an experiment designed to find out why the species is dying out.
The team strapped cameras and tracking equipment onto endangered Steller sea lions to see how they dived for food.
Early results from the project indicate that overfishing might not be the main factor in their decline as had previously been thought.
Male Steller sea lions measure 3m (10ft) and weigh more than 950kg.
This makes them the biggest of all sea lions.
These marine mammals once thrived on the shores of the North Pacific ocean. Now their numbers have dwindled to around 100,000. But no one knows why they are dying out.
Monday, January 9, 2012
Appeal launched for Patagonian grebe
Recent surveys on its coastal Patagonian wintering grounds indicate that the Endangered Hooded Grebe Podiceps gallardoi has declined by 40% in the last seven years and this, along with alarming new threats detected on its breeding grounds during 2011, indicate action is now urgently required to prevent the rapidly increasing threat of its extinction.
In response to these worrying findings, Aves Argentinas (BirdLife in Argentina) has mounted a wide-ranging offensive to protect this highly-threatened migratory species from further decline. In support, we are launching an international online appeal through the BirdLife Preventing Extinctions Programme to help fund the urgently required conservation action that they have already begun.
We are also seeking BirdLife Species Champions for the Hooded Grebe. If you or your company would like to find out about this opportunity please email species.champions@birdlife.org.
Discovered only as recently as 1974, Hooded Grebe has declined by as much as 80% in the last 30 years and as a result of surveys conducted in 2006 and 2009, the species was uplisted by BirdLife to Endangered on the IUCN Red List in May 2009. Recent counts on the wintering grounds last year, suggest the decline is steepening further.
“Our teams started to become really worried when we realised that there was more than one cause to tackle if we were to conserve the Hooded Grebe”, said Gustavo Costa, President of Aves Argentinas.
In many of the lakes in the grebe’s core distribution, exotic trout have been introduced for industrial fish production. “Trout rearing has reached the most isolated places, and this industry is threatening not only the future of the grebe but also the rest of the wildlife present in those environments”, Gustavo Costa added. Also evident are the increasing numbers of Kelp Gull Larus dominicanus, a known predator of the grebe that has benefited from both the fish industry and poor waste management at human settlements.
As if these problems were not already enough to push this struggling species over the edge, a breeding colony which Aves Argentinas was studying at Laguna El Cervecero, Santa Cruz Province in March 2011, was devastated by a sinister and ferocious invasive pest that is now advancing in western Patagonia: the American mink, Neovison vison. More than 30 breeding adult Hooded Grebes were found killed by mink at this one site, and a further 40-plus eggs were abandoned.
Saturday, December 3, 2011
Baltic seaduck take a dive
On Wednesday 1 December, a new report presenting the results of a census of wintering waterbirds in the Baltic Sea has been launched. The studies reveal that overall numbers have declined by more than 40% since the 1990s.
To read the full report Waterbird populations and Pressures in the Baltic Sea, please click here
Internationally coordinated counts were undertaken in 2007-2009 under the SOWBAS project (“Status of wintering waterbird populations in the Baltic Sea”), funded by the Nordic Council of Ministers. The total number of wintering waterbirds was estimated at 4.41 million, compared to 7.44 million during the last census in 1992-1993.
Of the 20 species covered, 11 decreased, including 7 that declined by more than 30%. The strongest declines were suffered by seaduck. Numbers of Long-tailed Duck, the most numerous wintering waterbird in the Baltic, declined by 65%, with similar declines recorded for Steller’s Eider (Vulnerable) and Velvet Scoter. Common Eider, Common Scoter and Red-breasted Merganser all declined by between 42% and 51%.
For some of these species, the Baltic is the most important wintering area in the world, holding the majority of their global populations. These declines are therefore of global concern, and could have implications for the species’ status on the IUCN Red List.
BirdLife has combined these results with available data from other parts of the world to review the species’ global status and propose appropriate changes. Detailed proposals are available for comment (until January 2012) on BirdLife’s Globally Threatened Bird Forums: http://www.birdlife.org/globally-threatened-bird-forums/
Most of these seaduck concentrate in the southern Baltic, but unlike some other waterbirds, no consistent climate-driven northward shift in their winter distribution was detected. However, climate change may be affecting them in other ways. Many of these species breed mainly in the Russian arctic or tundra, where they may be suffering from climate-induced ecosystem changes. Recent monitoring in autumn, as these birds arrive in the Baltic, has revealed worryingly low proportions of juveniles, implicating unsustainably low recruitment on the breeding grounds.
Other factors could also be involved, such as over-harvesting of certain species, or oil discharges from ships, which are known to cause significant extra mortality in some parts of the Baltic. Changes in nutrient loads could also be having an impact, and the report stresses the importance of eutrophication in determining food availability and thus the abundance and distribution of waterbirds. Finally, incidental bycatch in gill-nets has been reported in several Baltic fisheries, with diving species like seaduck being particularly susceptible.
Now that the trends of these species are known, the top priority is to diagnose and address the causes of their declines. Experience suggests that this is best achieved by bringing together key experts from across the species’ range to make progress in a coordinated and effective manner, at a flyway population scale and with international cooperation.
Discussions to organise a conservation planning workshop in 2012 have already begun, involving the IUCN-SSC/WI Duck Specialist Group, the Wildfowl & Wetlands Trust, BirdLife International, Wetlands International and the African-Eurasian Waterbird Agreement.
http://www.birdlife.org/community/2011/12/baltic-seaduck-take-a-dive/
To read the full report Waterbird populations and Pressures in the Baltic Sea, please click here
Internationally coordinated counts were undertaken in 2007-2009 under the SOWBAS project (“Status of wintering waterbird populations in the Baltic Sea”), funded by the Nordic Council of Ministers. The total number of wintering waterbirds was estimated at 4.41 million, compared to 7.44 million during the last census in 1992-1993.
Of the 20 species covered, 11 decreased, including 7 that declined by more than 30%. The strongest declines were suffered by seaduck. Numbers of Long-tailed Duck, the most numerous wintering waterbird in the Baltic, declined by 65%, with similar declines recorded for Steller’s Eider (Vulnerable) and Velvet Scoter. Common Eider, Common Scoter and Red-breasted Merganser all declined by between 42% and 51%.
For some of these species, the Baltic is the most important wintering area in the world, holding the majority of their global populations. These declines are therefore of global concern, and could have implications for the species’ status on the IUCN Red List.
BirdLife has combined these results with available data from other parts of the world to review the species’ global status and propose appropriate changes. Detailed proposals are available for comment (until January 2012) on BirdLife’s Globally Threatened Bird Forums: http://www.birdlife.org/globally-threatened-bird-forums/
Most of these seaduck concentrate in the southern Baltic, but unlike some other waterbirds, no consistent climate-driven northward shift in their winter distribution was detected. However, climate change may be affecting them in other ways. Many of these species breed mainly in the Russian arctic or tundra, where they may be suffering from climate-induced ecosystem changes. Recent monitoring in autumn, as these birds arrive in the Baltic, has revealed worryingly low proportions of juveniles, implicating unsustainably low recruitment on the breeding grounds.
Other factors could also be involved, such as over-harvesting of certain species, or oil discharges from ships, which are known to cause significant extra mortality in some parts of the Baltic. Changes in nutrient loads could also be having an impact, and the report stresses the importance of eutrophication in determining food availability and thus the abundance and distribution of waterbirds. Finally, incidental bycatch in gill-nets has been reported in several Baltic fisheries, with diving species like seaduck being particularly susceptible.
Now that the trends of these species are known, the top priority is to diagnose and address the causes of their declines. Experience suggests that this is best achieved by bringing together key experts from across the species’ range to make progress in a coordinated and effective manner, at a flyway population scale and with international cooperation.
Discussions to organise a conservation planning workshop in 2012 have already begun, involving the IUCN-SSC/WI Duck Specialist Group, the Wildfowl & Wetlands Trust, BirdLife International, Wetlands International and the African-Eurasian Waterbird Agreement.
http://www.birdlife.org/community/2011/12/baltic-seaduck-take-a-dive/
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