Study finds indications for recovery after ecosystem pollution

December 5, 2018, University of Konstanz

Environmental damage caused by human activity can reduce the number of plant and animal species dramatically. At the same time, very little is known about how biodiversity recovers after ecosystem pollution is curtailed and has been cleaned up. As was common in the mid-1900s, Lake Constance, one of the largest freshwater lakes in Europe, suffered from eutrophication, or nutrient contamination caused by agricultural and waste water run-off. A study by the universities in Konstanz and Glasgow has now revealed that one European whitefish species expanded its genetic variation through hybridization with other whitefish species during the period of eutrophication. The study, led by the Konstanz-based biologist Dr. Jasminca Behrmann Godel along with her colleague Dr. Kathryn R. Elmer from the University of Glasgow, was published in the journal Nature Ecology and Evolution. This genetic mixture contributed to an expansion in biodiversity once the ecosystem recovered.

The diminished water quality in Lake Constance due to eutrophication destroyed the natural habitats and led to the extinction of two of the five whitefish species that had only existed in this lake as well as to the hybridization of the three remaining species. This had an impact on commercial fisheries in the lake. In the 1980s, concerted efforts to reduce eutrophication quickly re-established Lake Constance's original state.

Biologists examined the functional phenotypical and genomic variation of the European whitefish (gangfisch: Coregonus lavaretus macrophthalamus) in order to demonstrate that its biodiversity expanded within a short period of time after the ecosystem had recovered from nutrient contamination. In less than ten generations, the European whitefish developed a wide variation in the number of gill rakers—which are used to filter plankton from the water—thus rendering it able to occupy a broader ecological niche than before eutrophication. This is one of the fastest evolutionary rates ever recorded in the animal kingdom.

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Antiguan Racers No Long World’s Rarest Snake - via Herp Digest

Fauna and Flora International, 10/20/18 

Antiguan racers are endemic to the twin-island country of Antigua and Barbuda. Following the introduction of invasive mammals (rats and mongooses) in the 1800s, the species suffered a drastic decline and, by 1995, only around 50 of these snakes survived on just one offshore islet.

Happily, following work by Fauna & Flora International and partners to eradicate the alien species and reintroduce the snakes onto other offshore islands cleared of invasive predators, the population and range of the Antiguan racer has increased to over 1,100 individuals spread across four separate sites.

ANTIGUAN RACER FACTS:

• Despite their name, these racers are actually rather slow. They prey on four endemic species of lizard, which they catch by waiting in ambush.
• The Antiguan racer is one of very few snakes in which males can be distinguished from females by their colour. Their colouration also changes dramatically with age.
• These placid snakes are harmless to humans – their only defence is to emit a musky smell when frightened.
• The Antiguan racer has incorrectly been declared extinct twice: the first time in 1936, and again in 2009.
• Most of the Antiguan racers alive today have been implanted with microchip tags for security purposes and to monitor their growth and survival.

Relocated squirrels moving to new areas, says charity

6 November 2017

Red squirrels relocated to woodlands in the north west Highlands are "flourishing and breeding", according to a conservation charity.

More than 80 squirrels were trapped in other parts of the Highlands in phases of the project led by Findhorn-based Trees for Life.

The animals were released in areas that had no squirrels, including Shieldaig.

Tree for Life said many of the squirrels were not only breeding but also spreading to other new areas.

Becky Priestley, the charity's wildlife officer, said: "Early indications are that this could be a real wildlife success story.

"The new squirrel populations are not only flourishing and breeding in their new homes, they are also starting to spread out into new areas - with squirrels being sighted as far as 15km away."

The project's initial relocations took place between the springs of 2016 and 2017, with the first 33 squirrels from near Inverness and also in Moray released at Shieldaig in Wester Ross.

This was followed by 22 more released at the Coulin Estate next to Beinn Eighe National Nature Reserve near Kinlochewe.

Thirty squirrels were also released at Plockton, in Lochalsh, where the landowners include The National Trust for Scotland.

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The amazing recovery of Yosemite’s yellow-legged frog

Date: October 5, 2016

Source: University of California, Santa Barbara

They say what doesn't kill you makes you stronger.

That old adage appears to hold true for the endangered Sierra Nevada yellow-legged frog (Rana sierrae), whose remarkable recovery in the face of myriad threats has now been documented in an expansive, data-rich study of the species in Yosemite National Park.

New research from UC Santa Barbara biologist Roland Knapp and colleagues shows that after decades of decline -- and despite continued exposure to stressors including non-native fish, disease and pesticides -- the frog's abundance across Yosemite has increased seven-fold, and at an annual rate of 11 percent, over the 20-year study period.

Those increases, occurring over a large landscape and across hundreds of populations, Knapp said, provide a rare example of amphibian recovery at an ecologically relevant scale. The findings appear in the early online edition of the Proceedings of the National Academy of Sciences.

"We now have a parkwide picture of what's happening in Yosemite, and it shows convincingly that these frog populations are increasing dramatically, " said Knapp, based at UCSB's Sierra Nevada Aquatic Research Laboratory in Mammoth Lakes. "These new results show that, given sufficient time and the availability of intact habitat, the frogs can recover despite the human-caused challenges they face."

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British bats 'showing signs of recovery'

18 December 2014 Last updated at 15:24

Populations of 10 British bat species are stable or increasing following previous years of decline, a new report has suggested.

The species included Daubenton's and Brandt's.

The Bat Conservation Trust (BCT) enlisted more than 3,500 volunteers to help with its National Bat Monitoring Programme.

The citizen science project collected data from 3,272 sites across Great Britain from 1997 to 2012.

In the report, the trust said the results revealed a "generally favourable picture" and "signs of recovery" for bats over the monitoring period.

The study did, however, generate different trends for Natterer's, serotine and pipistrelles.

The report added: "This study demonstrates that use of volunteer programmes can be successful in monitoring bat populations, provided that key features including standardised survey methods and volunteer training are incorporated.

"Some species that are more difficult to detect and identify may however require specialist surveillance techniques."

Source ...

California blue whales rebound from whaling; first of their kin to do so

Date:

September 5, 2014

Source:

University of Washington

Summary:

The number of California blue whales has rebounded to near historical levels and, while the number of blue whales struck by ships is likely above allowable U.S. limits, such strikes do not immediately threaten that recovery.

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Sea Otters Rebound from Exxon Valdez Disaster

By Andrea Thompson, Planet Earth Editor | March 03, 2014 04:04pm ET

Nearly a quarter of a century after the Exxon Valdez disaster dumped 11 million gallons (40 million liters) of oil into Alaska'sPrince William Sound, sea otter numbers have rebounded to levels seen before the spill, the U.S. Geological Survey announced Friday (Feb. 28) with a new study.

Sea otters (Enhydra lutris), found along the Pacific coasts of North America and Northeast Asia, are one of more than 20 types of animals that make their home near the shore affected by the March 1989 oil spill. The disaster occurred in prime sea otter habitat, according to the USGS study. The oil "drastically reduces" the ability of the otters' fur to provide insulation, the report said.

It is estimated that several thousand sea otters perished because of the spill, the USGS said in a statement, and subsequent monitoring showed that the animals were slow to recover, likely because oil lingering in their environment continued to affect them.

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Bat populations are recovering according to largest ever European study

Daubenton's bat - one of the ones

that showed an increase in numbers

January 2014: There is some good news for bats as a new report shows numbers have increased by more than 40 per cent between 1993 and 2011, after declining for many years.The report was carried out by the European Environment Agency (EEA) and 16 of the 45 bat species found across Europe were studied. Scientists compiled data gained from 6 000 hibernating sites across nine different countries and found overall these species appear to have increased by 43 per cent.

“It is extremely encouraging to see bat populations increasing after massive historic declines,” EEA Executive Director Hans Bruyninckx said. “It suggests that targeted conservation policies over the last years have been successful. But many bat species are still endangered, so preserving their habitats is still an important priority. Monitoring bats also helps understand changes in wider ecosystems, including climate change, as they are highly sensitive to environmental change.”

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Recovery of Hawaiian Green Sea Turtles Still Short of Historic Levels

May 29, 2013 — Calls to lift protections for the iconic Hawaiian green sea turtle may be premature, according to a new study led by a Stanford researcher.

Although the number of Hawaiian green sea turtles has increased since 1978 when the species was listed under the U.S. Endangered Species Act, the population may still be only a fraction of historic levels, the research shows.

"It's critical to compare the animal's population level to its historic abundance, not just to recent levels," said study coauthor John N. "Jack" Kittinger, an early career fellow at Stanford's Center for Ocean Solutions (COS).

Kittinger and his collaborators compared contemporary (1973-2012) and historical (1250-1950) nesting records of Hawaiian green sea turtles from fishery logs, archeological sites, Hawaiian-language newspapers and first-hand historical accounts. The researchers also gathered current nesting data from the National Oceanic and Atmospheric Administration's green turtle field monitoring program run by its Pacific Islands Fisheries Science Center.

The work yielded extensive data sets on the occurrence, abundance, geographic distribution and harvest of sea turtles in Hawaii spanning hundreds of years.

Analysis of these records and other archival sources revealed that 80 percent of major historic green sea turtle nesting sites have disappeared and many others have shrunk greatly in size. The only remaining significant nesting site, which accounts for 90 percent of green sea turtle nesting in the Hawaiian Islands, is vulnerable to sea level rise and other threats.

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List of Asian Species at Conservation Crossroads Released by Wildlife Conservation Society

ScienceDaily (Sep. 5, 2012) — Will the tiger go the way of the passenger pigeon or be saved from extinction like the American bison?

The Wildlife Conservation Society (WCS) today released a list of Asian species that are at a conservation crossroads calling for governments to take immediate action with The Three R's Approach: Recognition, Responsibility, Recovery.

The list includes: the tiger, orangutans, Mekong giant catfish, Asian rhinos, Asian giant river turtles, and Asian vultures. The announcement was made at the IUCN's World Conservation Congress convening in Jeju, South Korea through Sept. 13.

WCS says that each species can follow the path of the passenger pigeon, which went extinct in the early 20th century, or the bison, which was saved using the 'three R's' approach. In the case of the bison, which was decimated by overhunting, its plight was recognized, responsibility was taken, and recovery resulted with more than 30,000 wild individuals in existence today. WCS was directly involved in saving the bison by breeding animals in the Bronx Zoo and working with partners to reintroduce them into protected areas in the early 1900s.

Continued:  http://www.sciencedaily.com/releases/2012/09/120905134828.htm