Radio Telemetry

The first two weeks I was here the sun didn't shine more than eight or nine hours, total. It rained frequently, if not lightly all day then heavily in the late afternoon or overnight. I knew it would change, but I'm not sure I was expecting it to happen so suddenly and with such intensity. Newcastle and the surrounding area went from low- to mid-fifties, clouds, and rain to high-eighties, low-nineties, and not a cloud in sight in what seemed like a matter of days. I was enjoying sleeping in a little and not going in to work until 8:00 AM, but with temperatures quickly rising every morning I've had to forgo that little bit of extra sleep and head in to work at 7:00 AM. Who knows? If the weather stays this hot, I may just end up at work at 6.

Today the temperature peaked around 92. That farmer's tan I wrote about? It's here.

The receptionist at the BLM office, K, was kind enough to order me a few BLM t-shirts to wear in the field, lending some legitimacy to my position should I ever need to make claims to curious land-owners or recreationists. She asked what size I wore, and I told her a small in men's sizes or medium in women's. To give her the benefit of doubt, I don't know whether K ordered them directly or sent the order to the state office for someone else to fill, but regardless, the shirts I received were a men's size medium... and husky.

I am by no means a "husky" individual. I have no idea where the line of communication went wrong. I do hope that it wasn't K who decided I needed "husky" shirts.

Today was sage-grouse day. Once a week until the end of my internship I'm supposed to go out on Thunder Basin National Grassland and track down five radio-collared sage-grouse, four females and a single male. Get ready for some science! Fair warning: if you're not up to reading science-y things, you might want to skip the rest of this post.

Grouse (I keep wanting to say 'grice') are lekking birds. Each breeding season groups of males gather on high, visible spots in grasslands or prairies and try their best to attract mates. Males put on displays, dancing around, singing, and flashing their plumage. Females are attracted to the leks as spots to scrutinize males, and they love it, because they can compare potential mates side-by-side. When they're satisfied with a male, they mate and go along their merry ways. Females take off and eventually nest and raise their chicks alone, and males disperse when they no longer attract hordes of females to their hilltops with their dancing and singing.

Greater Sage-Grouse lek around late April, and females should be nesting now. My job this summer is to track down the grouse, determine if the females are nesting, find out how they're using their habitats and (eventually) find where they go to hide away for winter. How do I find the grouse, you ask? Radio telemetry.

Radio telemetry is one of my absolute favorite ecological monitoring methods. The technology is continually advancing, and over the years it's almost revolutionised our ability to track individuals and populations. It has been a key in helping to understand some of the most elusive species in some of the most remote locations, and, best of all, it's fun.

Imagine you've caught an animal in a live-trap, and you want to know how it spends its time, where it lives, where is travels, or how frequently it visits a particular area. But perhaps the animal lives in a dense environment, is extremely cryptic, has become trap-shy, or travels far faster than any human could. How do you answer those questions?

Captured animals are fit will small devices that transmit a unique frequency of radio waves. Mammals are generally fit with collars, whereas birds and bats are often given backpack-like devices or small boxes glued between the shoulder blades. New advances have led to smaller transmitters, some of which can even be implanted under the skin. The animal is then released and allowed to return to its normal activities.

Later, scientists can track the movements of the animal in the field, using a receiver that will recognize the signal emitted by the radio collar and an antenna to hone in on the animal's location. The process is somewhat akin to tuning the antenna on a television in hopes of getting the best picture. The antenna is swept slowly back and forth until the direction is identified from which the signal is strongest. The scientist then moves in the proper direction, stops, checks the direction again, moves on, stops, checks the direction, and so on and so forth until he/she either flushes the animal or gets close enough to see where it is. In environments too dense to transmit signals properly or with very elusive or fast-moving animals, airplanes are occasionally used for location. If time is short or the scientist doesn't wish to disturb the animal, a series of readings can be taking in a perimeter around the supposed location of the animal, and the points can be extrapolated to gain an approximate determination of the animal's position.

In short, radio telemetry is really cool.

So how did I fare today? Poorly. The batteries in our receivers are old and don't hold charge well, and both ran out before I was able to get close enough to find/flush a bird. Luckily, we just got our new batteries in today, so after my sad attempt at finding nesting females I returned to the office and installed a more reliable power source.