Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Pot–Grower’s Poison Taking Toll on Rare Fishers

18.07.2012
A new study by the Wildlife Conservation Society (WCS), the Integral Ecology Research Center, the University of California Davis and other partners shows that imperiled fisher populations are being poisoned by the use of anticoagulant rodenticides (AR) on public and community forest lands in California–likely those used illegally by marijuana growers.

The researchers conducted necropsies among 58 fishers and found that 46 of the animals (79 percent) were exposed to one or more of the toxic ARs, and four had died directly from AR toxicity.

The fishers were from two different populations: one occurring on tribal, private, and public lands in northwestern California and another within the Sierra National Forest in central California. Distribution of the poisoned fishers indicated widespread contamination of fisher range in California.

Fishers are likely exposed to AR when eating animals that have already ingested the rodentcide. They may also be drawn to the poison directly by bacon, cheese and peanut butter “flavorizers” that manufacturers add to attract rodents. According to the authors, it is unlikely the fishers were exposed to AR used legally at or near agricultural or residential areas as these settings are not suitable habitat. Nor did animals tracked by telemetry collars during the study venture into those environments.

Instead, the exposure points were likely encountered where AR is used illicitly as part of illegal marijuana cultivation in remote areas that overlap with fisher habitat. The study cites multiple examples of confiscation of marijuana plants and discovery of associated AR use in the region and notes that in 2008 alone, more than 3.6 million marijuana plants were removed from federal and state public lands in California, including state and national parks.

Members of the weasel family, fishers were once widely distributed throughout North America’s west coast but have incurred significant population decline and extirpation from portions of their former range. Populations inhabiting Washington, Oregon, and California have been designated a Distinct Population Segment (DPS) and declared a candidate for listing under the federal Endangered Species Act (ESA).

Study co-author and WCS Scientist Sean Matthews said, “Fishers play a vital role in the forests of the Sierra Nevada Mountains and the Pacific Northwest. With a body the size of a house cat and the disposition of their larger cousin, the wolverine, fishers keep forest rodent populations in check and are one of the only predators with the tenacity to regularly prey on porcupines. As fisher populations declined, they took refuge in the last remaining portions of mature forest in the Sierra Nevada and coastal mountains. Now a new threat has emerged in these remaining refuges.”

AR may also harm fishers by compromising the animal’s blood clotting and recovery abilities, decreasing its resilience to environmental stressors, and abandonment of dependent young due to direct mortality of adults killed by AR. During the study, the first documentation of a neonatal milk transfer of AR in fishers was recorded as a deceased six-week old kit was tested and found to have AR in its system. (Kits are dependent on mother’s milk until ten weeks of age.)

Matthews said, “The findings in this paper could signal a looming conservation threat for other species as well as fishers. As we discuss in the study, depletion of rodent prey populations upon which fishers and other animals feed, along with the anticoagulant poisoning threat might affect the Sierra Nevada red fox, wolverine, California spotted owls and other rare carnivores that inhabit the region.”

In their conclusion, the authors consider heightened awareness in removing AR when marijuana grow sites are dismantled and further regulation restricting the use of AR to only pest management professionals.

The study, Anticoagulant Rodenticides on our Public and Community Lands: Spatial Distribution of Exposure and Poisoning of a Rare Forest Carnivore, appears in the July 13, 2012 edition of the online journal PLoS ONE.

Co-authors of the study include: Mourad W. Gabriel of the Integral Ecology Research Center and the Veterinary Genetics Laboratory at the University of California; Sean M. Matthews of the Wildlife Conservation Society; Davis (UC-Davis); Greta M. Wengert of Integral Ecology Research Center; Benjamin N. Sacks of Veterinary Genetics Laboratory at UC-Davis; Leslie W. Woods and Robert Poppenga of the California Animal Health and Food Safety Laboratory System at UC-Davis; Rick A. Sweitzer and Reginald H. Barrett of the Sierra Nevada Adaptive Management Project at the University of California at Berkeley (UC-Berkeley); Craig Thompson and Kathryn Purcell of the Pacific Southwest Research Station—Sierra Nevada Research Center, United States Forest Service; J. Mark Higley of the Wildlife Department, Hoopa Tribal Forestry; Stefan M. Keller of the Department of Pathology, Microbiology and Immunology at UC-Davis; and Deana L. Clifford of the Wildlife Investigations Laboratory of the California Department of Fish and Game.

Scott Smith | Newswise Science News
Further information:
http://www.wcs.org

More articles from Ecology, The Environment and Conservation:

nachricht Preservation of floodplains is flood protection
27.09.2017 | Technische Universität München

nachricht Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Ocean atmosphere rife with microbes

17.10.2017 | Life Sciences

Neutrons observe vitamin B6-dependent enzyme activity useful for drug development

17.10.2017 | Life Sciences

NASA finds newly formed tropical storm lan over open waters

17.10.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>