Field notes, v667
Page 311
Image from the Biodiversity Heritage Library. Contributed by Museum of Vertebrate Zoology, University of California, Berkeley. | www.biodiversitylibrary.org
Transcription
INSPECTION TRIP OF ANAHO ISLAND WILDLIFE REFUGE, PYRAMID L., NEVADA July 3, 1950 10:00 am to 3:30pm Observers: LeRoy Giles, Fred Wright, David B. Marshall and Thomas H. McAllister of Oregon State Game Commission. Schedule: Visited all colonies to band young and make more complete estimates on the number of birds present. Estimates here given therefore supersede t hose made on May 15 and June 26, 1950. Data given below also includes summary of observations made on May 15 and June 26. Dates MARKED for observations below are for July 3 unless otherwise specified. Birds Eared Grebe - 2 seen in water off island. Western Grebe - Saw only one, but several seen on June 26 and May 15. White Pelican - Giles estimated 5,000 adults on May 15, which is the best observation to date on adults. Adults can be estimated to best advantage earlier in the season when more are present. Of the 5,000, 1,000 were at the mouth of the Truckee River. Since pelicans range OVER a vast area from this colony, many adults belonging to the colony went uncounted because of tours over the region. As an example on May 16, the day after Giles made his count 400 pelicans were counted on the Stillwater Wildlife Management Area. 1,160 young pelicans in 14 pods or colonies were counted on July 3. Also 16 e ggs, some of which may not have been fertile. Nesting was more progressed at lower levels on the island. As one went up the island to the top nesting areas was at successively LATER earlier stages. Two pods were at the top of the island having 59 nests containing a total of 80 young and 9 eggs. Pipping of eggs and newly hatched young were observed at this location. These two colonies were overlooked on previous visits. About 8 young, all that were in the lowest colony had apparently left the island. This colony was observed on May 15. Pods or colonies found on July 3 are as follows: 1. 60 young 2. 200 young 3. 300 young 4. 60 young 5. 850 young 6. 750 young 7. 200 young and 3 eggs 8. 300 young and 4 eggs 9. 10 young 10. 50 young and MORE 8 eggs 11. 30 young and 1 egg 12. 350 yo ng 13. 200 young 14. 800 young 1,160 young and 16 eggs. On June 26 roughly 75% of the fish regurgitated by the young pelicans were carp , the remainder being chubs (Siphateles obesus) and cui-ui (Chamistes cuius). On July 3 no dead carp or cui-ui were observed to be regurgitated, MX