Subject: Fw: June Fish and Wildlife Brown Bag Seminar - Fish eating birds!!
Date: May 29 21:54:46 2003
From: Jon. Anderson and Marty Chaney - festuca at olywa.net


Hi Folks - thought you might be interested about a seminar on birds and fish. To be held in Olympia at noon on June 11th.
Jon. Anderson
Olympia, Washington
festuca at olywa.net

>>> John Pierce 05/28/03 03:51PM >>>
Next Month's seminar will truly be a fish and wildlife seminar =:> Hope to see you there.

P.S. Note the room change this month. The seminar will be in NRB rooms 175a and 175b.

June 11, Noon-1:30

Where : NRB Rooms 175a & 175b

Natural Resources Building
1111 Washington St. SE
Olympia, WA 98501

Visitor Parking - Natural Resources Bldg: From I-5: Take State Capitol exit #105. This exit puts you on 14th Avenue. Go through the tunnel and turn right onto Capitol Way. Turn right onto 11th. Turn right at Washington, and then left into visitor parking on Level P-1. Take the elevator to the lobby.

Speaker: Walt Major III, UW School of Aquatic and Fisheries Sciences
Title: Distribution and Abundance of Piscivorous Birds along the Yakima River, Washington State: Implications for Fisheries Management.

Abstract: Understanding of the abundance and spatial and temporal distributions of piscivorous birds and their potential consumption of fish is an increasingly important aspect of fisheries management. During 1999-2002, we determined the abundance and distribution and estimated the maximum consumption (kg biomass) of fish-eating birds along the length of the Yakima River in Washington State. Sixteen different species were observed during the 4-yr study, but only half of those were observed during all years. Abundance and estimated consumption of fish within the upper and middle sections of the river were dominated by common mergansers (Mergus merganser) which are known to breed in those reaches. Common mergansers accounted for 78 to 94% of the estimated total fish take for the upper river or approximately 28,383 ?1,041 kg over the 4 yrs. A greater diversity of avian piscivores occurred in the lower river and potential impacts to fish populations was more evenly distributed among the species. In 1999-2000, great blue herons potentially accounted for 29 and 36% of the fish consumed, whereas in 2001-2002 American white pelicans accounted for 53 and 55%. We estimated that approximately 75,878 ?6,616 kg of fish were consumed by piscivorous birds in the lower sections of the river during the study. Bird assemblages differed spatially along the river with a greater abundance of colonial nesting species within the lower sections of the river, especially during spring and the nesting season. The abundance of avian piscivores and consumption estimates are discussed within the context of salmonid supplementation efforts on the river and juvenile out-migration.