Tuesday, June 22, 2010

"Blue's demise"

Three weeks ago (May 28/29) Blue roosted near the Botanical Gardens on the west end of Roatan Island, Honduras before over flying Glover Reef making landfall in Belize 30 miles south of Belize City on May 30.

West end of Roatan Island, Honduras

Glover Reef

From there he over flew the Gulf of Mexico making landfall just south of Brownsville, Texas on the Mexican side of the Rio Grande River by June 2. A total of 1150 miles in 4 days.

Blue's route May 28 - June 2

On June 1, Mark Prostor and I checked Blue's territory and found the site still occupied by only a lone female. No doubt that he would be one of the late arriving breeders, but not so late that he could not successfully raise a brood of young.

By June 5, Blue had added another 1000 miles and was located near Cunningham, Kansas. He'd been traveling 300 miles daily for more than a week, and early in the evening on the 5th, Blue found a well-treed farm yard surrounded by irrigated crop land.

Roost location June 5/6

Based on his rate of travel, I anticipated that his next set of GPS locations due 3 days later would show Blue's location to be near Lake Manitoba, and less than 700 miles from his breeding territory. Surprisingly, the location data on June 9th indicated little movement which could easily be explained by GPS error alone...worse yet, the activity sensor indicated that the PTT had not moved in 3 days.

Data we received on the 12th confirmed that the PTT was stationary, but our field crew surveys on Baffin Island, the Melville Peninsular and Rankin Inlet left little time to track down what had happened to Blue.

No activity from June 5 to 12 near Cunningham, KS

Once back in Edmonton, I contacted Kerri Steffen at Cunningham Courier. who passed me along to a couple of biologists with the Kansas Department of Wildlife and Parks. Over the next couple of days Mark Van Scoyoc, Ken Brunson (both with KS Wildlife and Parks) and I exchanged information about Blue's location data, PTT frequency, search strategies, possible outcomes and the area around the farm yard.

Yesterday morning, I received the following message from Mark...

...we found your transmitter and the remains of the male peregrine. Just a wing was left of the bird itself. Ken will be sending you some photos...

And a little later, this one from Ken (along with the images below)...
...I brought up our bat biologists who were using a radio receiver related to some transmittered bats about an hour away from us but, unfortunately, we could not get their radio to encode your frequency. It turned out that the transmitter and wing were not all that hard to find after all . Jeff Miller was the one who discovered it mixed in with some branches on top of a shed roof. Glad we were able to find it. Our best evidence is that Blue met its demise from the talons of a Great Horned Owl which had already claimed the farmstead as its territory...
Looking south to the farm yard

The yard and "starting point" for the search using PTT locations

Jeff Miller finds PTT and wing on the roof of a shed

The shed

PTT and Blue's wing

My thanks to Mark and Ken for their time and resources, and to Whitney Haskell, Jeff Miller, Mike Rader and Murray Laubhan. Their efforts have provided invaluable insight into the events that lead to Blue's demise.

From L to R Whitney Haskell, Jeff Miller and Laurie Yasui

The field crew (Alex Anctil, Poisey Alogut and Frankie Jean-Gagnon) currently working at Rankin Inlet report that a male and female are resident at the site where Blue bred last year, and that a clutch of 4 eggs was completed by June 21.

Alastair