DNA assay aids in identifying and protecting North American wolves, coyotes

NORTH CAROLINA STATE UNIVERSITY

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Forensics specialists can use a commercial assay targeting mitochondrial DNA to accurately discriminate between wolf, coyote and dog species, according to a new study from North Carolina State University. The genetic information can be obtained from smaller or more degraded samples, and could aid authorities in prosecuting hunting jurisdiction violations and preserving protected species.

In the U.S., certain wolf subspecies or species are endangered and restricted in terms of hunting status. It is also illegal to deliberately breed wolves or coyotes with domesticated dogs.

"If it's a case where you have a whole specimen, authorities can typically identify it based on physical characteristics, though similarity between some species makes that method less than ideal," says Kelly Meiklejohn, assistant professor of forensic science at NC State and corresponding author of the research. "If you're working with cross-bred animals, or incomplete specimens, you need DNA-based methods to accurately determine what species you have."

Although some U.S. federal laboratories perform DNA-based identification of wolves and coyotes, their methods and genetic reference databases aren't publicly available. Meiklejohn partnered with the U.S. Fish and Wildlife Service to see if it was possible to use a commercially available assay designed for dogs as a way to recover the mitochondrial genome from diverse North American canid species.

The mitochondrial genome is one of two genomes inherited from an animal's parents. Specifically, the mitochondrial genome is inherited from the mother. It is useful for species identification both because its circular shape makes it less prone to degradation, and because there are more copies of this genome per cell, increasing the chance of retrieving useful material from small or damaged samples.

The team used a method, called a 'hybridization capture,' in which about 80 base-pair long RNA fragments are used to isolate DNA for sequencing. Samples are incubated with the RNA fragments, and if there's a match, the fragment will bind with the sample's DNA. The bound DNA can be isolated and sequenced. In this case, the team used a hybridization capture panel designed for the dog mitochondrial genome.

"The fragments will bind if there is about 80% similarity, which is why we felt the dog kit would be useful for sequencing wolves and coyotes," Meiklejohn says. "Dogs only diverged from wolves around 20,000 years ago, so the mitochondrial genomes aren't that different."

They sequenced 51 samples, and were able to recover full mitochondrial genomes and successfully differentiate between four species of interest: dog, wolf, Mexican wolf, and coyote.

"Essentially, this finding means we can do more with less," Meiklejohn says. "In forensics we rarely have high quality DNA samples; they've usually been exposed to the environment and are degraded. The flexibility of this kit allows us to determine the species we're looking at, which in turn may aid in prosecuting hunting or breeding violations and protecting endangered canid species."

Environmentalists plan to file lawsuit over Idaho's new wolf law

 

 

Environmental groups have notified Idaho Gov. Brad Little and other state officials of their intent to file a lawsuit over an expanded wolf-killing law the groups say will result in the illegal killing of federally protected grizzly bear and lynx

 Environmental groups have notified Idaho Gov. Brad Little and other state officials of their intent to file a lawsuit over an expanded wolf-killing law they believe will result in the illegal killing of federally protected grizzly bear and lynx.

The Center for Biological Diversity, Western Watersheds Project and others on Monday gave a required 60-day notice of their intent to sue if Idaho officials don’t prohibit all hunting, trapping and snaring in grizzly bear and lynx habitat.

For lynx, the conditions could cover most of Idaho except for the southwestern portion of the state. For grizzly bears, the areas would include portions of northern, central and eastern Idaho. Wolves are found in roughly the northern two-thirds of the state.

In May, the Republican governor signed into law a measure lawmakers said could lead to killing 90% of the state’s 1,500 wolves through expanded trapping and hunting. It took effect July 1. Lawmakers who sponsored the measure, backed by hunters and the state’s ranching sector but heavily criticized by environmental advocates, said numerous times that the state is allowed to cut the number of wolves down to 150 before federal authorities would take over management of the species. They said reducing the wolf population would reduce attacks on livestock and boost deer and elk herds.

“Lynx, grizzly bears, and gray wolves all inhabit similar habitat types and geographic ranges in Idaho, and wolf hunting and trapping therefore frequently occur in areas in which lynx and grizzlies are also present,” the groups said in their letter. “Moreover, because snare and other authorized means of hunting and trapping are imprecise tools, they pose a substantial risk to non-target species, including lynx and grizzly bears.”

Besides Little, the letter was also sent to the members of the Idaho Fish and Game Commission and the directors of the Idaho Department of Fish and Game and Idaho State Department of Agriculture.

Roger Phillips, spokesman for the state Department of Fish and Game, said the agency doesn’t comment on pending litigation.

Little’s office didn’t immediately respond to a request for comment from The Associated Press.

Environmental groups filed a similar notice of intent to sue in Montana last month that also involves the potential killing of grizzly bears and lynx by wolf hunters and trappers.

A primary change in the new law allows the state to hire private contractors to kill wolves and provides more money for state officials to hire the contractors.

The law also expands the way wolves can be hunted and killed.

It’s not clear if the expanded methods and seasons to kill wolves would reduce the wolf population to 150. Republican state Rep. Fred Wood, a former member of the Idaho Fish and Game Commission, said the only way to do that would be to use poison, which is not in the new law.

However, hunters have said night-vision scopes, now allowed, could significantly increase the number of wolves killed. But the threatened lawsuit cites possible deaths of grizzly bears and lynx from expanded trapping and snaring of wolves.

“Idaho’s outdated plans for wolf killing will inevitably harm other native wildlife species,” said Patrick Kelly, Idaho director of Western Watersheds Project. “It’s unacceptable to allow imperiled species to be ‘collateral damage’ in Idaho’s war on wolves.”

The state Department of Fish and Game reported in February that the wolf population has held at about 1,500 the past two years. The numbers were derived by using remote cameras and other methods.

About 500 wolves have been killed in the state in each of the last two years by hunters, trappers and wolf control measures carried out by state and federal authorities.

Idaho Cattle Association Executive Vice President Cameron Mulrony told Capital Press the new law provides needed additional tools to control wolves, and “will get the ball rolling.”

The statute could be amended and administrative rules revised, both with legislative approval, later if necessary, he said.

Wolf pups born on Isle Royale, moose poised for decline

MICHIGAN TECHNOLOGICAL UNIVERSITY

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IMAGE: IN THIS IMAGE FROM APRIL 2021, AN EMACIATED AND NUTRITIONALLY STRESSED BULL MOOSE -- WHO IS ALSO SEVERELY IMPACTED BY WINTER TICKS -- BEDS DOWN ON THE ISLAND.view more 

CREDIT: MICHIGAN TECH

The COVID-19 pandemic halted the in-person wintertime survey of wolves and moose on the island for the first time in 63 years. Consequently, there are no estimates of wolf or moose abundance for 2021, and the next estimates are scheduled in February 2022. But though the Isle Royale Winter Study didn't happen quite as planned, researchers were still able to visit the remote national park in the spring.

Now, fieldwork has resumed and Michigan Technological University researchers have already uncovered new information about these two iconic wildlife populations. In particular, wolves produced at least two litters of pups, and moose appear poised for decline.

In the Isle Royale Winter Study, Michigan Tech researchers share other significant developments about curating the world's largest moose bone collection, advances in understanding of wolf foraging behavior and the nutritional health of the moose population.

Key points:

• The Isle Royale wolf population is likely growing. "We recovered footage of a group of four wolf pups taken in January 2021 by remote cameras at the east end of Isle Royale," said Sarah Hoy, research assistant professor in Michigan Tech's College of Forest Resources and Environmental Science (CFRES). "Additionally, observations of tracks and scats left by wolf pups last fall at two different locations suggest that there were probably two different litters of pups living at the east end of the island in September 2020."

• Wolves are specialized foragers. "Wolf foraging behavior seems driven by minimizing the risks associated with killing large prey, like moose, even when the differences in vulnerability among individual moose might seem relatively subtle compared to when predators are choosing between different prey species," Hoy said.

• Nutritional stress stacks the deck against moose, which holds significant implications for how moose will handle a warming climate. "We found that the nutritional health of moose was importantly influenced by how hot it is during the summer, and also by how deep the snow is in winter," Hoy said. "Moose tended to be more nutritionally stressed during winters with deep snow, which may be because deeper snow makes it more difficult for moose to move around and find food."

• The moose population is likely declining. "Moose really struggled to find enough food this past winter," Hoy said. "Because there have been such large numbers of moose on the island over the last five years and moose ate branches faster than the trees can recover and replace them, the amount of food available to moose during winter has been getting progressively worse each year since 2017.

• Winter ticks are worse than usual this year, as evidenced by moose with very little fur left in spring -- having scratched or bitten off almost all of their winter coats in an effort to rid themselves of the blood-sucking parasites. This is significant because blood loss to ticks can exacerbate the detrimental effects of food shortage. Despite the mild winter, depleted food supplies and ticks made life harder for the island's moose this year.

Hunting and hidden deaths led to 30% reduction in WI wolf population

UNIVERSITY OF WISCONSIN-MADISON

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MADISON, Wis. -- About 100 additional wolves died over the winter in Wisconsin as a result of the delisting of grey wolves under the Endangered Species Act, alongside the 218 wolves killed by licensed hunters during Wisconsin's first public wolf hunt, according to new research.

The combined loss of 313 to 323 wolves represents a decline in the state's wolf population of between 27% and 33% between April 2020 and April 2021. Researchers estimate that a majority of these additional, uncounted deaths are due to something called cryptic poaching, where poachers hide evidence of illegal killings.

The findings are the first estimate of Wisconsin's wolf population since the public hunt in February, which ended early after hunters exceeded the quota of 119 wolves within a few days. These population estimates can help the Wisconsin Department of Natural Resources (DNR) prepare for the next legally mandated wolf hunt this fall.

They also provide guidance to other states planning wolf hunts following the removal of federal protections announced in November 2020 and effective January 2021.

University of Wisconsin-Madison environmental studies scientists Adrian Treves, Francisco Santiago-Ávila and Karann Putrevu performed the research, which was published July 5 in the journal PeerJ.

Under a variety of population growth scenarios, the researchers estimate that Wisconsin now hosts between 695 and 751 wolves, compared with at least 1,034 wolves last year. The scientists say this likely represents the maximum current wolf population, because they incorporated optimistic assumptions about population growth and low poaching rates into their models.

This decline is despite the hunting quota of 119 wolves for non-native hunters, set with the goal of helping maintain but not reduce the state's wolf population. Ojibwe Tribes were granted a quota of 81 wolves, but they did not conduct a hunt.

"Although the DNR is aiming for a stable population, we estimate the population actually dropped significantly," says Treves, a professor in the Nelson Institute for Environmental Studies and director of the Carnivore Coexistence Lab at UW-Madison.

The new study suggests that about one-third of the population decline is due to hidden deaths in the wolf population, resulting from relaxed legal protections.

Previous research by the Treves lab showed that wolf population growth declined in Wisconsin and Michigan when legal protections were relaxed, regardless of the number of wolves legally killed. And Santiago-Ávila led research that found that Wisconsin's wolves and the heavily monitored Mexican wolves of the American Southwest disappeared at greater rates when lethal control methods were allowed.

Other studies by the lab of attitudes toward wolves suggest that when governments allow lethal management, would-be poachers are inclined to kill more wolves because the relaxed policies signal that predators are less valued.

Those previous findings helped Santiago-Ávila, Putrevu and Treves model the uncounted deaths in Wisconsin since last November.

"During these periods, we see an effect on poaching, both reported and cryptic. Those wolves disappear and you never find them again," says Santiago-Ávila, a postdoctoral researcher in the lab. "Additional deaths are caused simply by the policy signal, and the wolf hunt adds to that."

Treves and his team estimate that the population could recover in one to two years without hunting. Wisconsin law requires a wolf hunt between November and February when hunting is not prohibited by federal protections.

Following the federal delisting of wolves that became effective in January 2021, the DNR initially planned to conduct the first hunt in November 2021. But after a lawsuit, the DNR immediately implemented a wolf hunt at the end of February.

The research team hopes that the Wisconsin DNR and other states' natural resource agencies take advantage of their methods to develop a more complete assessment of the effect of new policies on predator populations.

"These methods and models are freely available to these agencies," says Putrevu, a doctoral student who also researches tiger populations in the Russian Far East. "They should take advantage of the best available science to meet their stated goals."