Lake County and an ornithological mystery
- On Friday the 13th, Doug Weidemann and I joined Brad and Kathy Barnwell at Lakeport and we canoed (Doug and I) or kayaked (Brad and Kathy) on Clear Lake south to Corinthian Bay. At Manning Creek we found a juvenile WILSON'S PHALAROPE swimming out on the lake. At Rumsey Slough we found two LEAST BITTERNS and a female NORTHERN SHOVELER. We also encountered 19 scattered nests of WESTERN and CLARK'S GREBES, mostly at Rumsey Slough. In the afternoon Doug and I saw another LEAST BITTERN--our third for the day--at Rodman Slough.
On Sunday the 15th, Doug and I canoed to the large grebe colony at Anderson Marsh. We saw an AMERICAN BITTERN and two COMMON MOORHENS at the south end of the island at the south end of Clear Lake. At the grebe colony we saw four adult (two male, two female) with four downy young RUDDY DUCKS, providing one of the few breeding records for the county. In the afternoon we canoed to the large colony of nesting grebes on floating mats of algae at the north end of the lake, near the mouth of Rodman Slough. A juvenile BAIRD'S SANDPIPER was standing alone on a thick mat of algae a few hundred yards from shore, allowing us to approach amazingly close. We also scoped Borax Lake from the road, spotting a single DOWITCHER (species unidentified) and a bunch of peeps, but nothing else unusual.
If you're wondering why we're spending so much time out on the lake, it's because we're contracted by the Redbud Audubon Society to study nesting Aechmophorus grebes. While studying the grebe colonies we encountered a few oddities that may interest some of you. A PIED-BILLED GREBE chick was alone and appeared to be abandoned in a nest within the midst of the Aechmorphorus grebe colony at Rodman's Slough on Friday the 13th, and on Sunday the 15th we noticed two smaller eggs among three much larger eggs in a nest in the Anderson Marsh colony. We suspect the eggs were dumped by PIED-BILLED GREBES and the chick was abandoned after it had hatched.
Finally, we have a bizarre ornithological mystery to contemplate: on Sunday the 15th, we found a dead juvenile CALIFORNIA GULL beside an Aechmophorus grebe nest with 11 entire, unbroken eggs at the edge of the colony on floating algal mats at the north end of the lake. We wondered how the 11 eggs got to the nest, whether a gull could carry them without breaking them, and whether the gull had been fatally speared from beneath by grebes defending their nests. Any thoughts?
Hidden Valley Lake, CA