Spotlight on the Prairie Ecosytem: Prairie dogs and Ferrets

 You have probably seen prairie dogs before, either in zoos or images, and know them to be extremely cute and playful prairie herbivores. However, you may be wondering what sort of creature the animal shown at the top of the page is! It is a black-footed ferret, another prairie dweller that preys exclusively on prairie dogs. The reason why you have most likely not encountered one is because they are critically endangered mainly due to scarcity of prey, disease, and lack of genetic diversity. Ranchers consider prairie dogs pests, since their burrows can break the legs of stampeding cattle, and because of the mistaken belief that they harm the grass quality. Articles dating back from 1902 stated that prairie dogs reduce range productivity, and have only been disproved recently. As a result of reading these false articles, ranchers began poisoning prairie dogs. However, poisoning prairie dogs not only kills the individuals, but transmits the poison to their predators, such as black-footed ferrets, coyotes, and hawks, thus killing them as well. The mass extermination of prairie dogs has also directly harmed ferrets, since ferrets must eat over a hundred prairie dogs a year to survive.

Another factor that has caused the death of both prairie dogs and ferrets is disease such as sylvatic plague and canine distemper. Plague is 100% fatal for black-footed ferrets, and is transmitted to them by infected fleas biting them or by eating contaminated prairie dogs. However, a plague vaccine meant for humans has proved successful for ferrets. Dusting burrows with flea pesticide is also successful. Canine distemper is not as prevalent as plague, but it is a major threat to the ferret population. It is spread by animals in the canine family, such as wolves and coyotes, as the name implies. Once again, an effective vaccine has been developed and is being administered to every captive ferret prior to reintroduction. However, these vaccines may be difficult and time consuming to administer. Another destructive factor is the genetic bottleneck, or a condition that results from inbreeding and causes forced reproduction between individuals that would not, under normal conditions, reproduce. This causes the exhibition of undesirable traits and a lack of genetic diversity. A genetic bottleneck is often the result of a population decrease.

 

 In order to prevent black-footed ferrets from becoming extinct, they must be bred in captivity and reintroduced. One method that scientists propose is the use of preconditioning. During preconditioning, ferrets are placed in outdoor pens for a minimum of 30 days, giving them experience hunting prairie dogs while also shielding them from predators. So far, approximately 3500 ferrets have been released in the wild. Now, around 500 have survived. In fact, 25 ferrets have just been reintroduced a few days ago in Arizona, on October 1st. Although this data seems promising, there is still much research to be done, especially on the issue of the genetic bottleneck. One possible solution that is currently being investigated is the use of artificial insemination. Through this process, semen from deceased males can be used to help female ferrets to reproduce. Thus, a deceased male's genes could be passed on to future offspring, offering more genetic diversity. 

 

To read more about black-footed ferrets, visit the website: http://blackfootedferret.org/home

Here is a video of a frolicking ferret kit being reintroduced:

https://www.youtube.com/watch?v=WiUbds5xGp4