Now that the long-term trend and Habitat Assessment Framework monitoring has been completed, we’ve been doing grazing reintroduction surveys (monitoring grasses at previously burned sites to determine when grazing can be reintroduced), scanning allotment study files (done!), GIS projects (also done!), and some highly anticipated wildlife monitoring.
I have been looking forward to getting wildlife experience pretty much ever since I interviewed for the job. We were getting experience indirectly by gathering data on habitat and learning about the forbs that are palatable for sage grouse. And, similarly, we have become extremely familiar with the diets of cattle. But what I was really looking forward to was bat and raptor monitoring, which due to unforseen factors was not as heavily emphasized as anticipated. Luckily, the wildlife biologists at our office were in close communication with one at Fish and Game and our mentor Joanna has been really flexible and supportive of us getting involved in any and all projects we could get our hands on.
Another hidden Idaho gem unearthed by our wildlife outings… Sand dunes!
Our first bout of wildlife monitoring involved two days of bat surveys. It was the first time any bat population monitoring had been done in over a decade. I’m sure most of you have heard of the white-nose syndrome (WNS), but for those who haven’t, it’s a rapidly spreading disease among bats that causes a prominent white fungus (Pseudogymnoascus destructans) to grow around their faces. And it’s just terrible. Some colonies and even entire species have been nearly decimated, populations dropping 90%. It has mostly been documented in the east, the first sighting hailing from New York in 2006, but is anticipated to spread westward any day.
So, to establish a baseline population of the bats in preparation for its imminent arrival, we used acoustic monitoring technology specifically designed to pick up the distinct frequencies of bats. The device is called AnaBat, and it’s pretty amazing. Before we set up the devices, the wildlife biologist established a grid with 4 quadrants in the study area, which encompassed sections of the Snake River as well as some residential and agricultural areas. In each quadrant, a portable AnaBat device was strapped to a post (either pre-existing, like a fence post, or a stake that we hammered) that is strategically facing an area with known bat activity. We also have to try to limit unnecessary ambient noises, like making sure the strap of the device is tucked in to make listening to the recordings less painful if it’s windy.
AnaBat doin’ its thing
Next, we programmed the device to start recording data at sunset. While we drove between quadrants to prepare the devices and waited for the sun to set before the next step, we were able to watch an incredible amount of birds, mostly raptors, in and around the Snake River Canyon, such as burrowing owls, red-tailed hawks, ferruginous hawks, eagles, prairie falcons, barn owls, great horned owls, magpies… It was great, and with the extra help of a high-powered Fish & Game spotting scope, the wildlife biologist, and a teenage birding prodigy intern, there was never a dull moment (or an unidentifiable bird).
The view of the canyon as the sun sets before we drove our transect
Next we mounted another AnaBat acoustic monitoring device onto the top of our truck. This time, the device is facing the top of the truck. The flatness and smoothness actually helps the acoustics bounce back at a good angle that makes the recording clearer. This sensor is connected to a handy palm pilot from the 80s that has an application installed that visualizes the frequencies of the different sounds that are picked up. Before we started driving along the transect, we recorded the temperature, time of sunset, lunar phase, temperature, wind speed, cloud coverage, humidity, etc. Bats tend to be more active the fuller the moon due to increased insect activity (attraction to light).
AnaBat sensor mounted on the top of the truck
Next, we drove and watched and listened for bat noises on the palm pilot. The sounds that the palm pilot picks up are echo location and hunting calls. Different species of bats have specific associated frequencies and ranges. Although some visualizations are pretty definitive, all recordings must be listened to in elongated 15 second sections by a biologist who has been trained in using the device (which involves a lot of sound physics). We were able to identify large and small brown bats, long-eared, Townsend’s big-eared, and a few other species.
Jesse, one of the wildlife biologists at our office, trained us to do pygmy rabbit surveys, which are usually done in the winter when there’s plenty of snow and easy to identify active burrows and fresh scat. The process is pretty straightforward. We monitored previously inhabited areas and a couple where they were suspected to be present based on the habitat. In general, they like loamy, soft, deep soils that are easy for burrowing (they are the only rabbit species that dig their own burrow) and tall sagebrush with at least 30% cover.
Their burrows are pretty distinct due to their size (about the size of a softball) and sightings of their scat nearby, which are incredibly small pellets the size of tic tacs or smaller. Trying to find them reminded me of looking for sheds with my co-workers while we were driving through pastures for use supervision. There are so many things that look like what you’re looking for (i.e. a dead sagebrush branch can look a lot like a mule deer antler when you’re in a moving car) and it almost always isn’t. Similarly, when you approach a mound of tall sagebrush with the right soil, good cover, not too rocky, and actually find a burrow. A lot of the times I’ll find a promising burrow and it’s slightly too big or too small or somewhere in between but no scat to confirm.
Most recently, we went out with Ross from Fish & Game again to do swan surveys. Tundra and Trumpet swans are known to migrate here during the winter, but unfortunately we weren’t able to spot any. This could be a result of the recent cold snap scaring them off to warmer areas. Nevertheless, I got a lot of practice identifying waterfowl and saw some familiar species I saw a lot in Florida like pelicans, gulls, cormorants, snowy egrets, blue herons, and sandhill cranes.
On our way between swan monitoring sites, we were able to stop at the Bruneau Dunes to look for the very rare Bruneau Dune Tiger Beetle, which we were not able to find but we did learn quite a bit about what to look for when trying to spot beetle burrows and how to lure them out (with a blade of grass!). And of course, the views were pretty breathtaking.
Lastly, we spent a couple hours getting trained in radio telemetry. Ross hid 6 sage grouse collars outside the Fish & Game office (in trees, bushes, etc.) and taught us how to use the radios and antennas while adjusting the dials (volume, gain, etc.) to key in on a frequency and locate a collar.
We learned about the different types of collars (radio vs. satellite), different sizes for different age classes and species, how to deactivate a transmitter using a magnet, ones that are solar-powered, and pre-programmed duty cycles (i.e. when an animal dies or goes into hibernation, the transmitter can either turn off completely or reactivate when they are awoken, or to turn on and off depending on the time of day to save battery).
In addition, we were able to practice using two different types of antennas (Yagi vs. “H”). The H antenna was a lot smaller and lighter and easier to use, in my opinion, but Yagi tended to be more accurate when trying to determine where a collar was once you get pretty close to its location. We also learned how to navigate when there are tall, dense, or metallic/electrical, structures that may be interfering with our signal and how to triangulate to find a location.
Anyway, that about sums up our wildlife training for the season!
Until next time,
BLM Shoshone, ID