Hello, all.

I am forwarding several messages from OBOL that were forwarded to me by Jay Withgott. The problem with Bald Eagles as predators on colonial (and noncolonial) birds is approaching critical. I don't have any idea what we can do about it, but eagles are now a serious threat to populations of a variety of bird species in the Pacific Northwest.

Gary Shugart told me that the big colonies on East Sand Island, at the mouth of the Columbia River, are now being decimated by a combination of eagle predation and predation by all sorts of other species when the eagles disturb the colonies. Our only big Caspian Tern colony is there, and in addition there is a significant Brandt's Cormorant colony. It is also a roost site for thousands of Brown Pelicans. Check the website Bird Research Northwest (http://www.birdresearchnw.org/) and click on Columbia River Estuary under Weekly Update.

Because the authorities have harassed Caspian Terns away from most other potential breeding sites and preserved East Sand Island as their sanctuary, eagle predation and disturbance represents a more serious problem for this species than it would have if they were allowed to breed where they wished to. That's the real conundrum now, and I think it is time for the agencies to rethink their attitudes toward fish-eating birds. These seabird colonies may be a lot more endangered than salmonid populations.

Dennis

Begin forwarded message:

>> From: "Wayne Hoffman" <whoffman at peak.org>
>> To: "OBOL" <obol at oregonbirds.org>
>> Date: Mon, 30 May 2011 13:37:19 -0700
>> Subject: [OBOL] Yaquina Head colony
>>
>>
>> Hi -
>>
>> I spent close to 3 hours at Yaquina Head this morning (May 30). The main Common Murre colony was under siege, and I expect it will fail this year. For the time being, the Murres on the smaller rock to the south and on the high rock off the cobble beach seemed to be doing OK.
>>
>> When I arrived, about 8:20 AM, an immature eagle was perched in one of the live Spruce trees just N. of the lighthouse. I would describe his plumage as 3rd cycle - perhaps delayed a bit relative to Sibley's illustration of "3rd year" - had the white and some pale on the face, but seemed to have a darker face and darker tail than in that illustration. He stayed there the whole time I was present. No other eagles appeared.
>>
>> When I got to the viewing platform, most of the top of the main colony rock was devoid of Murres. There were quite a few in the southern 1/4 of the top and a few on ledges on the sides. Six Turkey Vultures were walking around on top, feeding on 2 bird carcasses and on abandoned eggs. Western Gulls and about 8 American Crows were also hunting for eggs. Whenever a vulture would fly, the Murres would panic and fly off, and the egg-scavengers would move in. The bare ground was littered with eggs with holes in them. Over the next hour the vultures left, 1 by 1, and eventually Murres came in and occupied parts of the colony top. Then a Common Raven arrived. It lit and fended off a few attacks by crows and hopped / walked in to groups of Murres, trying to steal eggs. The Murres held their ground and stretched their heads and bills toward it. At one point it approached a Murre more or less by itself with an egg, and grabbed it by the wing and pulled it 6" or so away from its egg. It got back in time, however, and covered the egg. Clearly, 2 Ravens working together would have an easy time.
>>
>> After a few minutes, the Raven emerged from a clump of Murres carrying an egg, and walked and flew to an open area and pecked it open and ate the contents. Twice it was challenged by gulls, but drove them off. Took about 5 minutes to eat the egg.
>>
>> In addition, the Brandt's Cormorant and Pelagic Cormorant numbers remain much reduced from several years ago. - and seem lower than last year.
>>
>> Also seen:
>>
>> 2 Gray Whales
>> 2 Steller's Sea Lions, including a large bull that surfaced in the "cove just south of the main colony rock and roared several times.
>>
>> Wayne

-----
Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net



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