Sunset at Shirley Basin

We began the month doing Wyoming Toad (Anaxyrus baxteri) surveys once again. However this time instead of breeding surveys, where we were looking for tadpoles and egg masses, we surveyed for the adult toads specifically. The procedure is mostly the same with the exception that the plots we were surveying extended farther from the waters edge. When we captured a toad we measured lengths and mass and took a sample for chytrid fungus. This fungus causes an infectious disease in amphibians called Chytridomycosis which is believed to be a factor in the global decline in amphibian populations and is possibly a factor in the decimation of the Wyoming Toad population in the mid 1970s.

Wyoming Toad (Anaxryus baxteri)

After toad surveys, I assisted fisheries with their seining surveys. Seining is a method of catching fish using a seine, which is a net with poles fixed to either end, a weighted bottom and buoyed top. The net is dragged along either side of the shore and many of the fish in the river get trapped inside. We were doing a depletion removal study to estimate the actual abundance of fish species. This consists of three successive passes done with the seine per site and the number of each species of fish that was caught was recorded. If done correctly each pass should yield less fish then the last and the rate of decline can be used to determine species abundances. I also had my first experience electroshocking which is another method to determine fish species abundance. In this method, one surveyor administers a non-lethal shock to the water with an backpack electrical generator to temporarily stun the fish so the other surveyors can net any observed fish. Again three successive passes are done per stream section and actual abundance can be determined.

Black-footed Ferret (Mustela nigripes)

One of the most compelling things I did this month was Black-footed Ferret (Mustela nigripes) surveys. These remarkable animals are North America’s only native ferret and were once considered to be extinct until one was caught by a farmers dog in Meeteetse, WY in 1981. Since the discovery of the extant population, many breeding and reintroduction efforts have been underway to save the population and have been considerably successful. Black-footed ferrets main food source is prairie dog and they use their burrows to hunt, sleep, hide from predators, and reproduce. The ferrets historic range coincided with that of the prairie dogs. The project I was helping with is managed by the Wyoming Game and Fish Department and we were surveying the Shirley Basin population. The goal of the surveys was to attempt to determine population size but also to tag and vaccinate as many ferrets as possible. Surveys took place from 7pm until 6am as the ferrets are nocturnal. Everyone was given a section of land to survey and spotlights were used to locate eye-shine. Black-footed ferrets eyes appear an emerald greenish blue when light is shinned on them. Once a ferret was located it was followed until it entered a prairie dog burrow and then a trap was set in the entrance of the burrow and all other exits from the burrow were plugged. The trap site was then checked once per hour for any trapped ferrets. When a ferret was capture it was transferred to a tube that resembled the inside of a burrow and it was brought to the processing trailer where measurement were taken and vaccinations were administered. Once processed, the trap set up was disassembled and the ferret was released where it was captured. Over three nights of surveying I caught four ferrets, two female kits, a male kit, and a young adult male. Between the 10 survey areas 16 ferrets were captured and processed. We also observed many incidentals, including badgers, swift foxes, red foxes, coyotes, pronghorns, jack rabbits, and ferruginous hawks. Getting to work with and observe such an iconic species in the wildlife conservation world was an absolutely incredible experience and I couldn’t be more grateful that I got to assist in the conservation efforts for the species.

Note slightly visible eyeshine of Black-footed Ferret
Moments before releasing this female kit to her burrow

For the last half of August we completed our second round of trapping for herptiles North of the Ferris Mountains. This trapping period was great for garter snakes (Thamnophis elegans) as we trapped around the time that females were giving birth. Many of the garter snakes we caught this period were young of the year. We also caught our second Northern Leopard Frog (Lithobates pipens) which was an excitement. My most exciting opportunistic catch this period was a three foot long bullsnake (Pituophis catenifer sayi)! I also had the opportunity to tube and process a Prairie rattlesnake (Crotalus viridis), which was an incredible learning experience. The rattlesnake was a small female caught outside the office so we relocated her to one of out trap sites. Unfortunately we couldn’t count her in our data but fingers crossed we can catch her again later in the season. We added some sherman traps to three of our sites in an attempt to trap more mammals but they were much less successful then I was expecting based on past experiences. Only one deer mouse was captured who unfortunately had succumbed to the environment. Overall for mammals we caught plenty of deer mice and voles, plus a hand full of shrews. Overall it was a good trapping period but I am hoping for an increase in diversity for our next, and last, trapping period.

Northern Leopard Frog (Lithobates pipens)
Young of the year Greater Short-horned Lizard (Phrynosoma hernandesi)
3 foot long Bullsnake (Pituophis catenifer sayi)
Wandering Garter Snake (Thamnophis elegans vagrans)

-Keri – BLM – RFO

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