Journal 220
Aug. 9 - Brood Parasitism - Part II
In the past week I've seen juvenile cowbirds with Yellow-rumped Warblers, Northern Flickers, and Dark-eyed Juncos. Just how pervasive is this problem? I'm sure no one knows as there is probably no one studying the problem. However, if I saw three cases this week without even trying, the problem could be more significant than anyone realizes. It probably wouldn't impact much on local species like the junco and flicker, but it could have a serious effect on some of the scarcer neotropical species like the warblers.
It is difficult to talk about brood parasitism without mentioning the Kirkland's Warblers. The Kirkland's Warblers are one of the most endangered species on earth. They breed in Michigan and winter in the Bahamas. Their current population is about 3,000. Twenty years ago they were down to less than a 1,000 birds.
Kirkland's Warblers breed in the jack pine forests of the Huron - Manistee National Forests in Michigan. Scientists attributed the drastic decline in the Warbler population to loss of breeding habitat and brood parasitism by Brown-headed Cowbirds. The Warblers nested on the ground under the protection of low branches on young jack pines. Because of land clearing for agriculture and other developments, much of this habitat was lost. To address the problem of habitat loss, considerable effort has been made to protect existing habitat and to create new habitat. To mitigate the effects of brood parasitism, a concerted program of trapping Brown-headed Cowbirds was initiated. As a result of the two programs, the populations of the Kirkland's Warbler has increased significantly. The goal is to eventually get the Kirkland's Warbler off the endangered species list.
The juvenile Brown-headed Cowbird already looks like a candidate for Weight-Watchers as the frazzled Dark-eyed Junco stuffs another morsel of food into the yawning jaws of the parasite.
Aug. 13 - Shorebird Day
Mid-August is probably the best shorebird time as the annual southward migration is augmented by large flocks of sparkling juveniles. They are a joy to see not just because of their bright and tidy plumages, but because they are the promise of the future. Without the annual regeneration, survival of the species could be seriously jeopardized. I was counting on seeing a few juveniles at Holden Creek on my first birding trip in a week. The weather was excellent and the mosquitoes abundant. All I needed was a few flocks of shorebirds and the absence of Peregrines, Sharp-shinneds, and Merlins.
Yes, I know the juvenile American Goldfinches aren't shorebirds, but they were plentiful on the road to Holden Creek.
The first shorebird I saw was a Least Sandpiper. That's not surprising as they are often foraging in the salicornia and grass near the entrance. The Least were the most common peep of the day.
The bright, white plumage of the juvenile Westerns could have easily been confused with the Semipalmated's, but the oversized bill was certainly unmistakeable.
It didn't take long to find a Semipalmated Sandpiper. In fact, it didn't take long to find about 30. As usual, they were more "white" than their fellow peeps. Out of the approximately 200 peeps, about 15% were Semipalmated, 25% Western, and 60% Least.
At first I had difficulty getting close to the Semipalmated's. They were the first to move away when I approached.
After an hour of unsuccessfully stalking the Semipalmated's, I was ready to quit. But, on my way out, a Sharp-shinned Hawk scattered the various flocks in all directions. The only peeps left were 3 Least Sandpipers in a shallow pond right beside me. As I watched the flocks swirling around, one of the flocks joined the birds right next to me. There were about 30 birds and at least 20 were Semipalmated's. I didn't move anything but my shutter finger for the next hour as the peeps wandered withing 3 meters of me. I've often speculated that the shorebirds feel a measure of safety in the proximity of a person as it is like a scarecrow to keep the raptors away.
With the sun at my back and peeps at the optimum range for my lens, it was the perfect situation for some good pictures. However, there was one other challenge, and that was to try to catch a peep when it wasn't moving.
The peeps were perpetual motion with their heads bobbing like the head on a sewing machine. They were probably feeding on hordes of mosquito larvae.
Reflecting on Its Future - A Semipalmated Sandpiper pauses to contemplate the predicted consequences of global warming, war, excessive consumption, and the many other ways humans are destroying the earth
The only larger sandpipers around were 3 Pectorals. They flew the first time I encountered them, but the second time I was very slow and cautious, and they didn't fly.
It was interesting to observe the Pectoral's. They were cognizant of the alarm calls of the other peeps, but they check around before reacting. Most of the other peeps instinctively flew.
The juveniles are easy to identify as they have crisp, white fringes on their feathers. In the following photo, the fringes have all worn off on the post-breeding adult.
Aug. 15 - A brief look at a juvenile Baird's Sandpiper before it was flushed by the circling Northern Harrier.
On my way home from Holden I took the waterfront route hoping to encounter a wayward Red-necked Phalarope. There was no such luck. The best I could do was a pair of juvenile Glaucous-winged Gulls at the seaplane base. (Thanks Mike Tabak for the identification assistance.)
Aug. 14 - Legacy Marsh - Today was my birding day with Joe. We had to kill an hour before the tide was low enough to visit Holden Creek. We never expected anything, but halfway along the marsh we encountered flycatchers, wrens, sparrows, warblers, juncos, and swallows frolicking in the morning sun. We pulled over and Joe spotted a snag full of Barn Swallows. That's exactly the setting photographers are always looking for. No hydro lines or barbed wire fences.
By the time we made our way down to the snag, there were only three juveniles left. That was perfect as we knew they were waiting for breakfast in bed. They didn't have to wait long as the parents were back every minute or two with breakfast snacks.
It was great to be waiting for the adults to return, but the question was, "which of the three juveniles was going to be fed?" We had a good laugh each time we lost in the game of "Barn Swallow Roulette."
The answer was, "stay focussed on one bird." Eventually, it would get it's turn. However, it's always wise to pick a bird on the end of the branch as it is often the first mouth the adult sees. Sure enough. My end bird was fed 4 out of 5 times.
There was a variety of other birds to visit the snag while we were there. The only other photo I managed was the House Finch.
After the Barn Swallows, we visited Holden Creek. There was the usual mix of shorebirds but less than half the numbers yesterday. The only new bird was the Baird's Sandpiper which I included with yesterday's images. Actually, there was one other new bird and that was a Northern Harrier that circled low over my head. Unfortunately, it's impossible to shoot straight up with my camera and tripod set up. I envy those who have the Wimberly.
After Holden, it was off to Victoria. We made brief stops at Clover Point and Beacon Hill Park to confirm our thoughts that there would be no birds around in the heat of the day. It didn't help to see people clambering all over the rocks at Clover.
As usual, we stopped at Esquimalt Lagoon on the way home. The last time we enjoyed the Rhinocerous Auklet with a mouthful of sandlance. Today we got to practice flight shots with the Caspian Terns. (There were 3 or 4 Terns in the area. Apparently, Caspian Terns nested on the roof of the terminal building at Ogden Point. This might have been the first-ever nesting confirmation for the region.)
The Caspian Terns appeared to be hunting.
They would fly around and then circle, hover, and dive completely uner the water.
After watching this demonstration several times and not seeing any prey, I wondered if the terns were just skinny-dipping to cool off.
If only we could communicate with the birds. Wouldn't it be interesting to find out why the Trumpeter Swan spent the summer with the Mute Swans at the Lagoon? It certainly looked healthy in the water, but maybe it had difficulties flying, or maybe it was persuaded by the Chamber of Commerce promotion of Victoria being a "sexy" city.
Aug. 15 - Deep Bay - The only birds visible were a few gulls and Black-bellied Plovers. It was a typical summer day with more people than birds.
It was a joy to see the Black-bellied Plovers back for the fall and winter after their lengthy journey from the Arctic coast breeding grounds. I bet they had some interesting stories to tell about life on the Arctic coast. I wonder if any of them nested around Tuktoyaktuk? After seeing the King Eider photos that Margaret took at Cambridge Bay, I felt a little tinge of nostalgia for north. Maybe it's time to visit my old friend, Eddie Gruben, in Tuk.
