LAST MONTH, I was able to help out a team studying the migration patterns of ospreys that nest in Grand Teton National Park. The study began in 2010 and is a partnership between the national park and Craighead Beringia South, a non-profit wildlife research institute located in Wyoming. The group wants to preserve the osprey’s migrations, which will ultimately preserve the park’s biodiversity.
Craighead Beringia South researcher Bryan Bedrosian has been working closely with the study. He and his team are tracking ospreys with solar-powered satellite transmitters. This equipment sends signals to an Argos satellite, which is used to track animals like polar bears, killer whales, or other creatures that may travel long distances — even between continents.
In late April, my regional supervisor, Bill Bates, forwarded me an email asking for help retrieving a transmitter from the study. The osprey carrying it had died, then been covered by snow over the winter. The transmitter sent out a signal in October of 2012, but went silent after the snow began to fall. The team heard from it again in late March, as the snow melted from its tiny solar panel.
This expensive piece of equipment was in Dry Canyon, a tributary of Ninemile Canyon, in Carbon County. The birds being studied have traveled to Cuba, the U.S. Gulf coast and southern Mexico during winters. The young bird, which met some untimely end in Carbon County, was probably on its way to southern Mexico.
The osprey is in Utah’s Wildlife Action Plan, so as Sensitive Species Biologist, it’s my purview. But, I had another tie with the project: one of Craighead Beringia South’s Board Members, Maurice Hornocker, was my employer for many years. As a professional courtesy, we decided to see if we could locate the $4,000 transmitter and return it to Bryan.
Tyrell Mills, a DWR Technician, and I were able to drive within 300 yards of the reported location. Winter had left a downed tree and several rocks on the road, but we got around all the obstacles. I used a GPS unit to get us to the site. Then, I used a receiver that told me, once a minute, the strength of the signal being sent to the satellite.
The slope we were on was very steep and brushy, with some snow remaining. It was hard to stand upright, much less use electronic gear. As I thrashed around with the cords and gadgets, Tyrell worked the slope. After almost two hours he found some feathers, and followed their trail uphill to more feathers, bones and the transmitter in question. It was only about 25 yards from the location reported to the satellite.
The carcass had been completely scavenged, so all we could learn about the bird was that it was definitely dead and had somehow held onto the backpack. Even so, Bryan was happy to get the transmitter back and thanked us with a gift certificate.
So, where do Utah ospreys go over the winter? Based on the results of this study, we have reason to suspect some may just go south, but others may travel far to the east as well. We look forward to checking on further results from this study on line on the Craighead Beringia South website.