At 6:30 AM this morning Rock Dove Tours was on the road once again. Peter Gent and I (Bill Kaempfer actually had to work) headed east to Prewitt Reservoir in Northeast Colorado. Today was the day – a serious attempt for Cassin’s Vireo and Prewitt Res. had multiple sightings over the last ten days. This was my last chance to find the vireo in my home state. Yesterday, I had put out a call for help on the Colorado Birds listserve if the vireo was spotted. We arrived at 8:00 AM and decided to walk the inlet canal first. It was chilly only 38˚ F and we had very little bird action other than a House Wren and juvenile plumaged Red-headed Woodpecker for the first 40 minutes. Sometime around 9:00 AM Peter located a small flock of four birds – two Yellow-rumped Warblers, an Orange-crowned Warbler and to my utter amazement a Canada Warbler! Canada Warbler was a state bird for me and only the second one for Peter.
Soon after this discovery, we realized that warblers were flying through the trees everywhere around us! There were maybe a hundred individuals of eight warbler species in the flock including Townsend’s, Nashville, Black-and-White and Tennessee. For you people in Chicago, Ohio or New Jersey this mat not seem like that many, but this was the best warbler flock I’ve seen in Colorado in a long, long time!
Eventually we took a break from the flock and birded below the dam where we found virtually no birds. So around 12:00 PM we returned to the flock and join forces with Joey Kellner, Dick Schottler and Randy Lentz who were racing towards Prewitt from the east to see the Canada Warbler. This turned out to be wise move. We refound the flock very quickly and also soon had two additional warbler species – American Redstart and Yellow Warbler. Just as the other three guys drove up, Peter and I relocated the Canada Warbler. This kept everybody excited for the next half an hour. Eventually I said “Well I still need a Cassin’s Vireo”. Joey suggested that we should try Crow Valley Campground in the Pawnee National Grasslands. No sooner were the words out of his mouth when I spotted a vireo across the canal high in a cottonwood. It was a Cassin’s Vireo! Joey found the bird immediately, but it flew off before the others could see it. So Joey decided to entice the flock by playing an Eastern Screech-Owl tape. Warblers immediately flew towards us and joining them was the Cassin’s Vireo. It flitted above us for over two minutes giving everyone a great look and me a chance to shoot some subpar photos.
I’m sending the photos to JLD just to make absolutely sure it wasn’t a Blue-headed Vireo, however, Tony Leukering has looked at the photos and all of us feel confident that it was a Cassin’s Vireo.
All in all a hell of a day. A state bird and a year bird! Cassin’s Vireo would not be my blunder of the year as JLD had warned. Tomorrow I’m Alaska bound. On Sunday (standby) or Monday (confirmed) I fly to St. Paul on the Pribiloffs. Stay tuned. I smell a Siberian Accentor!