Fall Migration Monitoring

This fall we successfully completed our fifth season of banding and observation from Nora Ridge along the Rocky Mountain Front (RMF) in west-central Montana. This project is part of an ongoing effort to monitor trends in raptor populations of the northern Rocky Mountains, with an emphasis on Golden Eagles.

The 2010 season was our best season for weather in years, with warm, sunny conditions lasting the entire field season. Of 45 days of counting we had only three days of the “dreaded” east winds and only one day of measurable snow. This made for a very steady predictable flight, with migrants moving nicely along the western flanks of Nora and nearby ridges. These favorable weather conditions and the predictable migratory flight paths of eagles and other raptor migrants contributed to our record breaking 33Golden Eagles banded on the ridge! (See banding section for more details)

The Crew

As usual, we had a highly motivated field crew. Full season banders included RVRI executive director Rob Domenech and new comer, trapper/bander David “Clutch” Haines. We hung the nickname “Clutch” on David, as he had the ability to pull in these “clutch” eagle captures on days when all hope seemed to be lost. Also on board fulltime was Erik Enzien who has been chasing raptor migration around western Montana with Rob since the mid 1990s. Erik has been there for RVRI since day one. Besides being our graphic designer and builder of this newsletter, Erik is skilled birder and naturalist. Erik also proved to be great back-up trapper pulling in15 raptors, including several Golden Eagles. Veteran Vince Slabe slid in towards the end of September just as the eagle flight was starting to pick up. Vince brings his unique brand of humor and infectious enthusiasm, as well as, much experience to the team. Tyler Veto (former Willard Alternative High School student) timed his arrival to coincide with Vince. Tyler was supposed to be attending college classes! Anyway, Tyler has put in hundreds of hours working with RVRI and “knows the ropes” very well.

In addition and in classic fashion, Bryan Bedrosian showed up with an entire crew of his own! That crew consisted of Ross “Randall” Crandall, Kathy “Kat” and Dean Townsend, Jill Learned and Megan Ruehmann. When Bryan shows up, the energy level of the entire crew is amplified. Bryan’s crew stayed for a week, with the exception of Megan who stayed on for most of the peak season. Megan, a seasoned field biologist and photographer, was a delight to work with and great to have on-site! Finally, rounding out the crew and heading up the count were new comers Sarah Norton and Adam Shreading. Adam and Sarah fit right in with the crew and did an outstanding job of heading the count. Their enthusiasm (even on slow days) never waned and they always had their eyes to the sky. Furthermore, they worked tirelessly to give us the heads-up on in-coming raptors to the banding station.

Count Totals from Nora Ridge

Golden Eagle MigrationObservations were conducted from September 7th through October 30th. During this period eight days were suspended due to unworkable weather conditions and only three days were cut short due to poor weather. A total of 2,047 raptors were counted in 309 hours of observation, comprised of 16 species, including Turkey Vultures. The Golden Eagle total came in at 851 and comprised 41 percent of all observed migrants. Our highest count in one day occurred on October 6 when Sarah and Adam tallied 139 raptors, including 65 Golden Eagles.

Raptors species observed

Golden Eagles 851 (42%), Sharp-shinned Hawks 468 (23%), Cooper’s Hawks 134 (7%), Red-tailed Hawks 156 (8%), Rough-legged Hawks 76 (4%), Northern Goshawk 55(3%), Northern Harrier 47 (2%), American Kestrels 37 (2%), Bald Eagle 33(1.6%), Merlin 19, Peregrine Falcon 10, Ferruginous Hawk 4, Osprey 3, Broad-winged Hawk 2, Prairie Falcon 1, Unidentified Accipiter 61(3%), Unidentified Buteo 38, Unidentified Raptor 30, Unidentified Eagle 4, Unidentified Falcon 3.


Banding Summary Fall 2010

We banded from September 18th through November 1st (weather permitting), for a total of 36 trap days on the ridge, compared with 19 days in 2009. As previously mentioned, we couldn’t have asked for better weather; this accounted for the high number of trap days. We banded a total of 134 raptors, including 36 Golden Eagles this season, 33 of those caught on Nora Ridge. This is a new RVRI record for Golden Eagles caught on the ridge! (Please see table below for complete totals.)

We had our first ever recaptured Cooper’s Hawk this season. The adult female was captured September 23rd by volunteer Jen Callahan. Jen trapped and banded hundreds of Cooper’s Hawks while working with HawkWatch International and made the capture look easy. This hawk was first captured and banded on Nora Ridge on September 18th 2008 by RVRI bander Tyler Veto. At that time, she was two-years-old. She looked to be in excellent condition and after some standard measurements we released her to continue on her southbound migration.


Another highlight was Vince Slabe’s capture of a 12 pound, adult Female Golden Eagle now know as Elaine for our Adult Golden Eagle Satellite Tracking Project .

Thanks to our dedicated crew and many helpful volunteers for making the fall 2010 our most successful Golden Eagle trapping and banding season to date!

Special thanks go out to Liz and Jerry Cain for providing housing and wonderful hospitality to our field crew!


Fall (Sept. through Oct. 2001-2010) Capture Totals

Capture Summary Nora Ridge 2010                 Combined Fall Capture Totals 2001-2010
AK 0     AK 14
BE 1     BE 10
BW 0     BW 3
CH 11     CH 121
GE 36     GE 220
GR 0     GR 1
ML 0     ML 12
NG 9     NG 140
NH 1     NH 21
PG 0     PG 4
PR 0     PR 6
RT 1     RT 18
RL 15     RL 105
SS 60     SS 242
Total 134     Total 917*
American Kestrel (AK), Bald Eagle (BE), Broad-winged Hawk (BW), Cooper’s Hawk (CH), Golden Eagle (GE), Gyr Falcon (GR), Merlin (ML), Northern Goshawk (NG), Northern Harrier (NH), Peregrine Falcon (PG), Prairie Falcon (PR), Rough-legged Hawk (RL), Red-tailed Hawk (RT), Sharp-shinned Hawk (SS)


* Includes Grassy Mountain 2007 and Rogers Pass 2001 – 2004 band totals