Prairie Dog Blog

prairie dog biology research

The search continues May 12, 2010

Filed under: Uncategorized — lorensackett @ 04:28

During the last few weeks, I have spent all my time trying to find prairie dogs.  A simple task in Boulder, it has proven to be tricky with the shier Gunnison’s prairie dog (Cynomys gunnisoni), which live in less densely populated colonies and do not clip vegetation the way that black-tails (C. ludovicianus) do.  Because of these two life history traits, they are much less conspicuous, and can be difficult to spot even when you know you’re at a colony.  Furthermore, plague seems to be taking a heavy toll on populations at the edge of the Gunnison’s prairie dog range– dozens of people pointed me to colonies that had existed within the past few years, and I arrived to find only unmaintained, unoccupied burrows.

Prairie dog researchers at a colony that is slowly recovering from plague

Plague is not the only threat to prairie dogs.  In many places, prairie dogs are seen as pests and are poisoned continuously over large areas.  Eliminating several populations near each other decreases the likelihood that they will be able to recover, because empty colonies can not be re-colonized from nearby animals.  The processes of extirpation (extinction of a single population) and re-colonization are known as metapopulation dynamics.  In a metapopulation, a series of populations function together, so that when one dies, it can be rescued by individuals from another population.  However, when many local populations die out simultaneously, there are no source populations to rescue those that have gone extinct.  This can lead to contraction of a species’ range, which may be what is happening to Gunnison’s prairie dogs.

This is a black-tailed prairie dog in Boulder... she was not shy at all, and let me get very close for pictures!

Nonetheless, after much searching and asking expert opinion, I was guided to a small colony in Springerville, AZ.  In colonies with low population density, deciding where to set up traps is of the utmost importance.  Prairie dogs are trap-shy, and will avoid traps if they can.  Before attempting to catch any, we bait the traps and hold them open so that the animals can get used to getting free food out of the traps and be less apprehensive about them.

This black-tailed prairie dog is not trap shy!

While my frustration at setting traps in 50+ mph winds mounted, various signs of life reminded me how much fun field work is, particularly in prairie dog colonies:  because they build burrows, their colonies are home to many other critters that share the burrows– lizards, rattlesnakes, rabbits, burrowing owls, toads, wyoming ground squirrels and more.  Prairie dogs also aerate the soil and move nutrients to the surface where it is more available to plants, so they can increase plant diversity in an area.  They also attract predators such as hawks, coyotes and ferrets.  Their colonies are therefore places of high species diversity– this is one reason to be concerned about prairie dog declines: many other species would also decline in concert.

A small assortment of species found on prairie dog colonies:

Yucca flower
beetles in a prickly poppy on a black-tailed prairie dog colony

Wyoming ground squirrels are found with white-tailed and Gunnison's prairie dogs

Primrose, Oenothera

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2 Responses to “The search continues”

  1. Lee Says:

    It will be very interesting (and sad) if you find their range or # of colonies has shrunk as much as it looks like they might have.

    • lorensackett Says:

      I know, you’re right. What I’ve seen so far is already pretty suggestive that they are not everywhere they used to be. There many places reported to be “overrun” with prairie dogs where there is no evidence of them now. Sometimes I’ll find caved-in burrows, which might mean plague came through somewhat recently (because the burrows are still there), but lots of times there is just no outward sign there were ever prairie dogs in the area (as you know!). I might attribute this to me not being able to read a map or understand directions, but it turns out everyone I talk to has the same thing to say (“No, you don’t want to trap there; there haven’t been prairie dogs there in years”, or “I looked all over that area because the range map said they existed there, but I found nothing”).

      I’m going to start making records (via GPS coordinates) of where prairie dogs do not exist, because data on species absence is hard to come by and very valuable. At least that way I will be generating lots of data! 🙂


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