Intensive agriculture, done secretly in forests, has a big impact on wildlife such as fishers.

CDFW Wildlife Investigations Lab Blog

The WIL’s nongame wildlife veterinarian, Deana Clifford,  has coauthored an article describing the impacts of illegal marijuana cultivation on wildlife.

Dr. Clifford and her co-authors are members of a multidisciplinary, multi-organizational working group advocating a strong science-based approach to assessing the impact of illegal cultivation on public lands.

The article entitled “Silent Forests?  Rodenticides on Illegal Marijuana Crops Harm Wildlife” appears in the current issue of The Wildlife Professional magazine  published by The Wildlife Society (TWS).

Click here to see the article.

Click here to see additional photos associated with the article.

Click here to read the original peer-reviewed publication examining rodenticide poisoning and exposure in fishers.

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Lynx and Bobcat in Northeast

There are lynx sightings in Vermont and a new bobcat management plan in New York.

In New York, the bobcat management plan offers a road map for managing the species over the next five years. Bobcat numbers in the state are up, the report says:

All indications, including harvest trends, suggest that bobcats have increased in abundance here and in surrounding states, and observations have become more common in recent years. Based on analysis of harvest data, we estimate New York’s bobcat population to be approximately 5,000 animals in areas where regulated hunting and trapping seasons have been in place since the 1970s. Estimates are not available for populations expanding into western and central New York.

Because of this, the plan includes opening some new areas of the state to bobcat hunting and changing the bobcat hunting season in other areas for the sake of consistency. The report also mentions investigating the possibility of reestablishing bobcats on Long Island, in the urban southeast corner of the state.

Find a link to the management plan and a short description of it on the NYS Department of Environmental Conservation’s website, on the bobcat page, here.

In Vermont, it’s the rural northwest corner of the state that is seeing an increase of lynx sightings, according to the blog of the US Fish and Wildlife Service’s Northeast Ecological Services.

A total of eight lynx track intercepts were recorded during two survey efforts in February and March. The track patterns and genetic analysis indicated three to five distinct individuals, some of which were traveling together.

The animals traveling together were likely a mother and her young, the blog says, which suggests a breeding population in the area.

Read the entire blog post, here.

Photo: Lynx track, courtesy Vermont Fish and Wildlife Department

Considering their deep-forest habitat, fishers should be safe from rodenticides, but this study shows how urban environmental problems were brought into the wilderness.

CDFW Wildlife Investigations Lab Blog

A peer-reviewed paper released today in the online journal PLoS One documents deaths due to anticoagulant rodenticides in fishers, an elusive forest carnivore in the weasel family.  The study shows that a high percentage of fishers tested have been exposed to these rodenticides.

The study was led by UC Davis, and involved researchers from the nonprofit Integral Ecology Research Center, UC Berkeley, United States Forest Service, Wildlife Conservation Society, Hoopa Tribal Forestry, and the California Department of Fish and Game’s Wildlife Investigation Lab.

The research team was surprised by their findings because fishers live in the mature forests of the national forests, national parks, private timberland and tribal community lands – nowhere near urban or agricultural areas where one might expect to find evidence of rodenticide use.

Examination of the areas where exposed fishers lived shows that their habitat overlaps with illegal marijuana…

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Role of Predators in Ecosystem Balance

Do wolves and other large predators keep deer and other large herbivore populations in check, or is the food supply that really limits the herbivore population?

Two Oregon State University biologists did a meta-analysis of 42 published studies and found that large predators play a huge role in keeping ecosystems in balance. The analysis spanned North America and Eurasia, which may be why the study was published in the European Journal of Wildlife Research.

But it’s not a single predator alone that keeps the herbivores at levels that allow for a healthy mix of plants to grow, the paper also says. When an ecosystem hosts at least two large predators — such as wolves and bears, or wolves and lynx — each predator has an impact on a different part of its prey’s life cycle, reducing the population more than one alone.

Read the article in the European Journal of Wildlife Research, here. (Fee or subscription required.)
Or here.
Read an article from the Environmental News Service, here.
The OSU press release is here.

Photo: Yellowstone wolf, courtesy of Oregon State University


More States Turning to Night Hunting for Problem Animals

North Carolina, Arizona and Tennessee are among the states that are allowing night hunting for problem species like feral swine, coyotes and mountain lions when existing hunting practices fail to reduce populations, says an article in USA Today.

Night hunting is allowed in 42 states, the article says, quoting data from the Indiana-based National Predator Hunters Association.

In the article, a coyote coexistence advocate is quoted as saying that hunting does little to reduce population levels of the fecund coyote. That’s a sentiment shared by many wildlife managers was well, regarding both coyotes and feral swine.

Read the USA Today article here.
PDF article on feral swine in New Hampshire Fish and Game’s magazine.

Photo: Feral swine piglet. If only they were all this cute. By Steve Hillebrand, courtesy US Fish and Wildlife Service

Scent Marking Won’t Keep Coyotes Away

Coyotes are territorial and mark their territories with urine. There are plenty of studies that show predator urine keeps prey away (such as keeping deer away from a garden with coyote urine). And using territorial marking has worked in repelling African wild dogs. But the trick doesn’t appear to work with coyotes.

A study reported in the last issue of The Wildlife Society Bulletin found that using coyote urine to mark off an area to keep other coyotes away, not only didn’t repel them, but only served to have coyotes linger in the area.

Read the article in Wildlife Society Bulletin. (Subscription of fee required, but the abstract pretty much tells you all you need to know.)

A Ph.D. student of that paper’s lead author did a similar study a few years ago, with captive coyotes, and got a similar finding. Read her doctoral thesis, with references to the predator/prey studies and other background info on the general concept — here.

Coyote photo by Steve Thompson, courtesy US Fish and Wildlife Service

Writing the Book on Wolverines

Before recent research on wolverines in the greater Yellowstone region, not much was known about these predators, says an article in the Billings Gazette. To wrap up the eight-year project, the article says, the research team, lead by Bob Inman of the Wildlife Conservation Society, has published an article in the Journal of Wildlife Management.

The article “Spacial ecology of wolverines at the southern periphery of distribution” was published online in December 2011. (Subscription or fee required.)

The Billings Gazette article implies that we’ll be seeing more research from this study published soon.

The Wolverine Blog (yes, there is one) offers a link to the blog of Forrest McCarthy, one of the researchers on the project. Read it for a behind-the-scenes view of the research, here.

Photo: Wolverine, Credit: Steve Kroschel, courtesy US Fish and Wildlife Service

Winter Research Roundup

In New York State, a recent survey of the spruce grouse population revealed that there are not many of the birds left in that state. A revised management plan seeks to restore the population.
An Albany Times-Union article about the survey and results
A link to download the spruce grouse management plan.

New York State has also released a management plan for bobcats. The plan includes a survey of the state’s current bobcat population. Comments on the plan are being accepted until February 16.
Read an article about the plan in North Country News, here.
Here’s the state’s bobcat page, with a link to the management plan.

In California, the Department of Fish and Game is looking for volunteers over 16 years old and in good health to help count bighorn sheep in the San Gabriel Mountains on March 4. There is an orientation on March 3.
Read an article from KPPC, southern California public radio, here.
Go to a website dedicated to the count, here.

Also in California, the US Fish and Wildlife Service will review the status of the San Bernardino flying squirrel. It’s soliciting information about the flying squirrel and its habitat from state and federal natural resource agencies until April 2.
Read the article in the Riverside Press-Enterprise
The US Fish and Wildlife service press release is here.

Bobcat photo courtesy of the New York State Department of Environmental Conservation.

To Bring Back Lynx, Bring Back Wolves

A paper in the current issue of the Wildlife Society Bulletin says that when gray wolves are removed from an ecosystem, Canada lynx populations take a double blow. One blow comes when elk and deer populations explode and eat all the shrubs. That leaves the lynx’s prey, the snowshoe hare, with nothing to eat and no where to hide.

The other blow is that without wolves maintaining the “ecology of fear,” coyote populations also increase. And while coyotes will eat anything, they really like to eat rabbits, hares and other creatures of that size. In places where deep snow pack does not keep the coyotes away, lynx can find themselves with little to eat.

Yes, this is yet another example of mesopredator release, but as the pithy Science news article (subscription required) points out, in Canada they have both wolves and lynx. In the U.S. there are places without wolves where lynx have suffered a mysterious decline. It will be interesting to see what happens to lynx populations in places with growing wolf populations.

Read the Oregon State University press release here.

Read an article in the Minneapolis Star Tribune here. And here’s a write-up from the East Oregonian.

Photo: Canada lynx, courtesy of Oregon State University

Ct. Lion Came from Midwest

As reported in the New York Times yesterday, DNA from the mountain lion struck by an SUV in Connecticut last month matched the general profile of mountain lions from South Dakota and more specifically, DNA collected from fur, blood and scat collected in Minnesota and Wisconsin. A necropsy did not find the usual signs of a captive animal, such as an implanted microchip or clipped claws.

Read the whole story in the New York Times, here.

The Connecticut Department of Energy and Environmental Protection press release also notes that the animal spotted in Greenwich appears to be the same animal that was killed in Milford. Read the release here. 

And yes, you read that correctly: Connecticut combined its departments of energy regulation and environmental protection on July 1. Read that press release here.

Photo: Ironically, this is the same photo that illustrated the news that the US Fish and Wildlife Service had declared the Eastern mountain lion extinct. Clearly, it is not the Connecticut mountain lion.