Download Document

Seabirds
Penguins
Albatrosses, shearwaters, petrels
Pelicans, cormorants, boobies
Gulls, terns, skuas, puffins
Diving ducks
Loons, grebes
“Waterbirds”
Herons, egrets
Ducks, geese, swans
Shorebirds
Global seabird declines
% of species in each IUCN Red List category
Red List Indices for (a) seabird and non-seabird
species; (b) coastal species, pelagic species
and listed in Agreement on the Conservation of
Albatrosses and Petrels (ACAP)
Threats/factors for decline
Seabirds
Pelagic seabirds
Coastal seabirds
Puget Sound declines
• Common marine birds declining
– 19 of 30 most common species in no. Puget
Sound decreased by ~20% from 1978-2004
• Since 1979, marine bird numbers in the
Puget Sound region has dropped 47%
• Western grebe populations declined by
95% over last 20 years
Likely factors (Puget Sound)
•
•
•
•
•
Forage fish population declines
Changing migration patterns
Predation/hunting
Habitat loss
Fisheries interactions
– Bycatch from active fisheries
– Derelict fishing gear
• Harm to Arctic breeding grounds
Puget Sound studies
• PSAMP Winter Seabird Surveys (plane)
• WDFW
• Puget Sound and Washington Coast
Seabird Population Trends (boat)
– WDFW, USFWS
• Puget Sound Seabird Survey (shore*)
– Seattle Audubon
• Rhinoceros Auklet Ecology (colony)
– WDFW, UPS, NOAA
Foraging ecology/behavior
• Indirect evidence
– Inferred from diet and movements
• Bill load contents, stomach contents
– Auklets, terns, cormorants
• Regurgitated pellet analysis
– Gulls, terns
• Tagging studies (satellite, TDRs), radio
– Auklets, terns, cormorants
• Radar
– Marbled murrelets. passerines
Foraging ecology/behavior
• Direct evidence
– Observing individual behavior/movements
• Line/strip transects (at-sea)
• Scan and focal animal sampling (shore)
Puget Sound Seabird Survey
•
•
•
•
Monthly (Oct.-Apr.)
High tide (4-hour window)
Shore-based (but of water)
Random, pre-selected sites
• Binoculars/spotting scope
• Geese, ducks, swans, loons, grebes,
cormorants, gulls, terns, alcids
• Spp., #, distance, bearing, sex ratio,
flocks, weather
Scan/focal sampling
• Scan sampling
– Counts of individuals in proscribed area(s)
• Generates species densities, community
composition, habitat association
• Noting behavior (standing/sleeping, walking,
foraging), generates # or % per behavior
• Focal animal sampling
– Individual behavior over proscribed time
• Time-stamped behaviors
• Note predators/competitors, habitat
• Generates time budgets, consumption data, etc.
•
•
•
•
Capture rates
Handling times
Prey selection
Kleptoparasitism
•
•
•
•
Migration timing
Habitat associations
Prey associations
Restoration activity