Tufts of grizzly fur being used to determine genetic health of population

In particular, researchers are looking to see if bears from the northwest corner of Montana have wandered into the Yellowstone ecosystem. To date, no,” [Charles] Schwartz said. Getting those genes into the greater Yellowstone ecosystem could provide a needed boost for the 550 to 600 grizzlies that live in and around the park.

“The GYE has the lowest diversity of the populations in the lower 48,” Schwartz said.

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As a result they are doing DNA analysis of bits of grizzly fur to see if the Yellowstone population needs genetic augmentation.

Story by Mike Stark. Billings Gazette.


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  1. Robert Hoskins Avatar
    Robert Hoskins

    What the grizzly bears of Yellowstone need is not artificial genetic augmentation but unimpeded movement corridors to central Idaho and Canada.

  2. Chuck Avatar

    I would love to see grizzly bears in Southwest Idaho.

  3. Tai Avatar
    Tai

    What a waste of money!!!! If you’re worried about genetic diversity for Yellowstone grizzlies, just trap a few grizzlies from the Northern Continental Divide Ecosystem, ship them to Yellowstone, and let the bears have at it.

    In a perfect world, a new world order that changed state and federal land management policies to physically “link” Yellowstone’s grizzlies to grizzlies in the NCDE and the Bitterroots would be ideal. We don’t live in a perfect world.

    I certainly applaud those who work for a perfect world and sensible management of our public lands. I just don’t see it happening anytime soon. Meanwhile, genetic diversity for Yellowstone’s grizzlies is cheap and easy via artificial insemination by imported bears from the NCDE. Claiming that the only way to achieve genetic diversity for grizzly bears is physically linking Yellowstone to the Yukon is a red herring argument.

  4. SAP Avatar
    SAP

    Uh, is that a joke about “artificial insemination”?

    Duckboy Co. has a funny postcard about that:

    http://www.duckboy.com/

    Also, I haven’t had that much coursework in formal logic, so I’m not clear how arguing for linkage habitat is a “red herring.” While it may be untrue to say that connectivity is the ONLY way to fix the lack of genetic diversity, I don’t see how it’s a “red herring.”

    See:

    http://www.fallacyfiles.org/redherrf.html

    There are other arguments besides genetics for naturally re-connecting these populations — namely, climate-driven changes in habitat, and demographic stochasticity.

    Note also that there is no immediate genetic crisis with Yellowstone grizzlies:

    “A University of Idaho study published in 2003 said there’s no impending genetic disaster threatening Yellowstone’s isolated grizzly population, but the shrinking gene pool could spell trouble decades down the road.”

    Decades.

    So, re-connection may not happen anytime soon, but it doesn’t need to happen next week anyhow. We have time.

    And, I’m not so sure that it would end up costing so much more to let the bears “run themselves” via linkage habitat versus an intensive management program of shipping bears around and monitoring them to make sure they interbreed.

    The Gazette article repeats the mistaken notion that one or two migrants per generation is all it would take to maintain genetic diversity. Delve into the population genetics literature and you’ll find that the term “effective migrant.” That’s an animal that immigrates and produces offspring that survive — in other words, its genes actually enter the new gene pool.

    Most people recognize that effective migrants will be only a subset of the total number of migrants, because some will die, some may be infertile, some may not succeed in rearing offspring.

    For a grizzly bear example, look at the Cabinet Mountains augmentation program, where it looks like one of some number (can’t recall, it wasn’t that many) of translocated females from the mid-1990s actually lived and raised cubs.

    So, we’d really be looking at moving and monitoring somewhere around 6-10 bears every decade, then monitoring them and their genetics to make sure they’re interbreeding and affecting the gene pool.

    I don’t know how much that costs. I don’t know how much it would cost to let bears recolonize vacant habitat in southwest Montana, either, although they’re already doing that.

    Bears from Yellowstone are now living within 20 miles of I-15; from the other end, bears from the Blackfoot Valley are crossing I-90 and moving toward the Big Hole. How far apart are these populations now? It could be less than 40 miles in some instances already. How much has that cost?

    I prefer (subjective value preference of mine) to let wildlife populations be as wild as we can let them. I’d rather not run them like livestock. I’d rather they be able to spread out and respond to habitat changes on their own, in their own intriguing ways. Having them depend on us for everything is something I’d like to avoid, for my aesthetic kicks as well as for practical reasons: do we really want to have the fate of the Yellowstone grizzly bear be completely at the mercy of President Jenna Bush in 2038? Keep them as an island population that depends on federal “inputs,” and that’s where we could end up.

    I’d sure prefer to spend money on Yellowstone grizzlies than on illegal wars of imperial conquest, or tax breaks for GM, or net-energy-loss ethanol. Let’s cut the fat there, then we can talk about what’s a “waste of money.”

    (Without belaboring the point, I will mention that a lot of PRIVATE philanthropic money has already gone into preventing conflicts with grizzlies in southwest Montana and on the southern end of the NCDE — collaborative conflict prevention is probably one of the biggest factors in the re-colonization that is currently occurring.)

  5. Dan Stebbins Avatar

    This is one of the real concerns about maintaining a healthy Griz population in the GYE. We don’t know for sure whether it can survive the inbreeding.
    Robert is right though, the best we could hope for is that somehow Grizzlies would make their way down here from Canadian populations.

  6. Tom Avatar
    Tom

    Relocating “problem” grizzlies within either the NCDE or the Greater Yellowstone Ecosystem often seems to result in it finding its way back to the same area where it got into trouble, then it winds up being a dead bear.

    Why couldn’t some alleged “problem” griz from the NCDE be relocated into remote areas of the GYE – or vice-versa – which would be in concert with the Gazette article? There’s very little chance that the bear would be able to find its way back to its former problem area. A linkage corridor between NCDE-GYE is hoped-for but may never actually happen without help.

    The potential genetic diversity realized by such a relocation would be a great positive, far outweighing (IMO) the cost of the ~300 mile relocation.

    It would seem that Wyoming, in particular, would welcome dumping off grizzlies of any type from the GYE into the NCDE in Montana. Could this be accomplished by some agreement or working arrangement between the two states with minimum involvement or oversight by USFWS – Dept of Interior/Kempthorne?

  7. Tai Avatar
    Tai

    SAP–genetics bore me but you’re obviously up to speed on the topic. I couldn’t follow your . . . umm . . . rambling comments. Don’t take that the wrong way. Could you give us a step by step guide on why, genetically, it’s important to link grizzlies in Yellowstone with grizzlies in the Yukon. Or why importing a grizzly or two a year from the Yukon to Yellowstone won’t do the genetic job. If you’ve got the answers, it would be very useful information. I’ve always thought that when it came to grizzly bear issues, the Yellowstone to Yukon initiative was more about land use issues than genetics. I’d like to be proven wrong. And I think current public land management in the US and Canada sucks.

  8. Tai Avatar
    Tai

    Tom–one reason why state and federal agencies aren’t about to relocate so called “problem” bears is that in 1996 or so, a girl camping on National Forest Service land near Tucson, Arizona got nailed by a so-called problem bear that had been relocated by the Arizona Dept. of Fish & Game. Cost the state (taxpayers) over a million bucks for an out of court settlement.

    The Arizona Dept. of Fish & Game presented a paper about the incident at an annual Western Black Bear Conference. It had a chilling effect on the amount of leniency western state fish and game departments are willing to give bears.

  9. doug Avatar
    doug

    SAP, you mentioned that “Bears from Yellowstone are now living within 20 miles of I-15; from the other end, bears from the Blackfoot Valley are crossing I-90 and moving toward the Big Hole. How far apart are these populations now? It could be less than 40 miles in some instances already.”
    Has this been verified? If so, this is great news and is quite encouraging! I think that if we continue to protect the rest of the Griz populations under the ESA and try and protect habitat, they must just link up sooner than we think, would be great!

  10. SAP Avatar
    SAP

    Tai –

    you’re right, my last post was a little rambly! I’m on the road right now, so I can’t sit down and write a detailed post on the ins and outs of linking grizzly bear populations. I’ll do that when I get back to Montana.

    For now, let me point out one parenthetical phrase in my post: “subjective value preference.”

    I am not 100 percent on board with the popular “corridor” mania, because they fail to acknowledge that a major part of the debate revolves around subjective value preferences. There are too many advocates out there with too little understanding of population viability trying to sound authoritative.

    Because we all “know” that inbreeding is “bad,” (although domestic and captive populations can evidently stand a fair amount of it) these advocates grad onto the genetics argument for linkage, when, as you concisely pointed out, we could fix any genetics problems by moving bears around.

    [[It would cost money to move and monitor enough bears to make a difference, and a legitimate cost comparison between that and linkage would be very interesting.]]

    But some poorly-informed advocates try to make it sound like there’s simply no way that translocations would work . . . or that Yellowstone MUST be connected to Yukon Territory or grizzlies will go extinct next week.

    That’s misleading, but I doubt they’re trying to be misleading — I think they just don’t know any better. I know it doesn’t make a very good sound bite to talk about demographic stochasticity and subjective value preferences — grabbing the public’s attention with “INBREEDING!!” and “SCIENCE SAYS WE HAVE TO DO THIS!!” is far more effective.

  11. SAP Avatar
    SAP

    Tai – here’s a little more about genetics:

    “. . . one to two translocated bears may not be enough. Typically, population geneticists refer to “effective migrants,” which is only those individuals that succeed in dispersing to a different population of conspecifics, breeding, and successfully rearing young to breeding age. In most any wild population, it is necessary to assume that effective migrants will be only a subset of the total number of migrants, because some are likely to die having failed to breed, or fail to rear offspring to independence. Thus, it may be necessary to translocate a larger number of bears from the NDCE (Miller and Waits 2003).

    Finally, Vucetich and Waite (2000) argue that the one (effective) migrant per generation rule of thumb for maintaining genetic diversity may be inadequate for populations that fluctuate temporally; they suggest that actual required numbers of effective migrants could be greater than 10 or 20 per generation, depending on the taxa and the magnitude of the fluctuations. Considering the apparent recent fluctuations in the size of the Yellowstone grizzly population and the great changes that are likely to affect abundance of key foods for this population, it is clear that we ought to view this population as one that experiences significant temporal fluctuations.”

    Miller, C. R., and L. P. Waits. 2003. The history of effective population size and genetic diversity in the Yellowstone grizzly (Ursus arctos): implications for conservation. Proceedings of the National Academy of Science 100(7):4334-4339.

    Vucetich, J. A., and T. A. Waite. 2000. Is one migrant per generation sufficient for the genetic management of fluctuating populations? Animal Conservation 3:261-266.

  12. SAP Avatar
    SAP

    doug –

    the IGBST would confirm that grizzlies are ranging far west of YNP, into the Centennial and Gravelly Mountains. Other highly reliable sightings indicate grizzlies within 25 miles of Dillon; there was one grizzly within 10 miles of Dillon in — I think — 1997. It was killing sheep and was euthanized, unfortunately.

    From the other end, a grizzly from the NCDE was illegally killed with an arrow in 2005, southwest of Anaconda:

    http://www.mtstandard.com/articles/2005/09/29/newsanaconda/hjjejahaijgdhg.txt

    Since then, there have been other sightings south of that location. If the bear that got killed did it, others can, so the sightings have more credibility now.

    There’s a lot of work to do to get ready for grizzlies moving back in to that country.

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