PSG2010 Abstracts.Pdf
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asterisk = speaker underline = eligible for student award CORRELATING SEABIRD MOVEMENTS WITH OCEAN WINDS: LINKING SATELLITE TELEMETRY WITH OCEAN SCATTEROMETRY Josh Adams*,1,2, and Stephanie Flora3. 1U.S. Geological Survey, Western Ecological Research Center, Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, CA, 95039 USA, [email protected]; 2Department of Zoology, University of Otago, Dunedin, New Zealand; 3Physical Oceanography Laboratory, Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, CA 95039 USA Satellite telemetry studies of seabirds are now common and have revealed impressive flight capabilities and extensive distributions at sea. Linking seabird movements with environmental conditions over vast expanses of the world’s open ocean, however, remains difficult. Seabirds of the Order Procellariiformes (e.g., petrels, albatrosses, and shearwaters) depend largely on wind and wave energy for efficient flight. We present a new method for quantifying the movements of far-ranging seabirds in relation to ocean winds measured by the SeaWinds scatterometer onboard the QuikSCAT satellite. We apply vector correlation to evaluate how the trajectories (ground speed and direction) for five procellariiform seabirds outfitted with satellite transmitters are related to ocean winds. Individual seabirds (Sooty Shearwater, Pink-footed Shearwater, Hawaiian Petrel, Grey-faced Petrel, and Black-footed Albatross) all traveled predominantly with oblique, isotropic crossing to quartering tail-winds (i.e., 105° to 165° in relation to birds’ trajectory). Entire track line trajectories were significantly correlated with co-located winds. Greatest correlations along 8-day path segments were related to wind patterns during birds’ directed, long-range migration (Sooty Shearwater) and movements associated with mega-scale meteorological phenomena, including Pacific Basin anticyclones (Hawaiian Petrel, Grey-faced Petrel) and eastward- propagating north Pacific cyclones (Black-footed Albatross). We suggest that vector correlation can be used to quantify movements for any marine vertebrate when tracking and environmental data (winds or currents) are of sufficient quality and sample size. Vector correlation coefficients can then be used to assess population- or species-specific variability and used to test specific hypotheses related to how animal movements are associated with fluid environments. RECENT POPULATION TRENDS IN WESTERN DOUBLE-CRESTED CORMORANTS: RESULTS FROM AN UPDATED STATUS ASSESSMENT Jessica Y. Adkins*, Daniel D. Roby, Donald E. Lyons, Karen N. Fischer, Timothy Marcella, Yasuko Suzuki, Peter Loschl, and Daniel Battaglia, USGS - Oregon Cooperative Fish and Wildlife Research Unit, Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR, [email protected] Since the most recent status assessment for the entire Pacific Coast population of Double-crested Cormorants (Phalacrocorax auritus) was published in 1995 by Carter et al., the distribution of this population across its breeding range has changed dramatically. This is primarily due to the increase in the breeding population in the Columbia River estuary, which grew from 6,200 pairs in 1997 to up to 13,800 pairs in 2007. Preliminary estimates for British Columbia, Washington, Oregon, and California suggest the current Pacific Coast breeding population of Double-crested Cormorants is ca. 26,000 breeding pairs. This is an increase of ca. 9,000 breeding pairs from Carter et al. (1995). Most of this increase can be attributed to the Columbia River estuary, which currently accounts for approximately 45% of Pacific Coast breeding pairs. In contrast to this growth, numbers in coastal British Columbia, Washington, and parts of California have declined. The 2009 breeding estimate in coastal British Columbia is down ca. 80% from a peak of 1,981 breeding pairs in 1987 (Moul and Gebauer 2002). The 2009 coastal Washington breeding estimate is down 51% from the 1992 estimate of 1,618 breeding pairs (Carter et al. 1995). And the 2008 estimate of 1,625 breeding pairs in Northern California is down from the 2003 estimate (2,437 breeding pairs; Capitolo et al. 2004), but similar to the estimate for 1989-1991 (1,633 breeding pairs; Carter et al. 1995). Increasing bald eagle (Haliaeetus leucocephalus) populations and episodic human disturbance may be important factors causing declines in some regions. FORAGING ECOLOGY AND DIET COMPOSITION OF CASPIAN TERNS IN SAN FRANCISCO BAY Lindsay Adrean*1, Daniel D. Roby1, Ken Collis2, Donald E. Lyons1, S. Kim Nelson3, and Daniel Battaglia1; 1USGS Oregon Cooperative Fish and Wildlife Research Unit, Oregon State University, 104 Nash Hall, Corvallis, OR 97333 USA, [email protected]; 2Real Time Research, 53 SW Roosevelt Avenue, Bend, OR 97702 USA; 3 Oregon Cooperative Fish and Wildlife Research Unit, Oregon State University, 104 Nash Hall, Corvallis, OR 97333 USA The largest breeding colony of Caspian Terns (Hydroprogne caspia) currently resides in the Columbia River estuary and numbers approximately 10,000 pairs. The impact of this colony on survival of out- migrating, threatened and endangered juvenile salmonids has caused resource managers to attempt to relocate most of these terns to areas outside of the estuary. One proposed relocation site is Brooks Island in San Francisco Bay, which currently supports a Caspian Tern breeding colony of ca. 800 pairs. Based on studies conducted during 2003-2005, however, Sacramento River salmonids are a part of the diet at this colony, and fisheries managers are concerned that relocated terns could reduce survival of ESA-listed salmonids in the Bay Area. In 2008 and 2009 we collected diet composition information and used radio telemetry to investigate the foraging ecology of Caspian Terns nesting on Brooks Island. Diet composition data indicated that consumption of salmonid smolts has increased from 3% of prey items in 2005 to 10% in 2008 and 2009. Several popular foraging sites were in close proximity to new release sites for non-listed hatchery-raised Sacramento River Fall Chinook. TRAPPING AND BAND RECOVERY OF CALIFORNIA LEAST TERNS AT SAN DIEGO BAY COLONIES, 2008-2009 Jeff Allen*1, Elizabeth Copper2, and Robert T. Patton2, 1Department of Biology, Willamette University, 900 State St., Salem, OR 97301, USA, [email protected]; 2Avian Research Associates, 830 Orange Ave., Ste. K, Coronado, CA 92118, USA Although the population of the federally endangered California Least Tern (Sternula antillarum browni) has increased significantly over the past 20 years, fledgling production has remained low since 2001. It appears that aging and mortality of the majority of the breeding population may surpass productivity and replacement by younger breeders, threatening a rapidly accelerating decline in breeding pairs. Trapping of previously banded adults nesting at each colony around San Diego Bay was conducted in order to estimate an age profile of the population and to determine feasibility of a larger scale trapping project. During the 2008 and 2009 breeding seasons, 185 previously banded birds and 67 un-banded birds were trapped. Ages ranged from two-years old to 21, with average age of eight to nine years. As anticipated, birds nesting at their natal colony accounted for the highest percentage of the bands recovered, followed by individuals nesting at a different colony but still within the San Diego Bay colony complex, those from Mission Bay or elsewhere in San Diego County, and the lowest percentage had been recruited from Orange and Los Angeles County sites. CONSERVATION BIOLOGY: WHY MOST OF US ARE INTO SEABIRDS Daniel W. Anderson, University of California, Department of Wildlife, Fish, & Conservation Biology, Davis, CA 95616 USA, [email protected] Almost forty years ago, one of our early Lifetime Achievement Award (LAA) recipients, Jim Bartonek, with L. W. Sowl (1974), called seabirds “Alaska's most neglected resource.” This was largely true for most of the world's seabirds. Now, seabird conservation and seabird biology are at the forefronts of marine biology and natural history in many disciplines. Both aspects, seabird study and seabird conservation, have strong roots in the Pacific Seabird Group and other seabird-oriented organizations, worldwide. John Croxall, another PSG Lifetime Achievement Award recipient, stressed the importance of conservation as a lifetime goal of all seabird biologists and managers. And, as recently stressed by John Weins (at the most recent national conference of The Wildlife Society, 20-24 Sept. 2009), the “pure” science of [seabird] ecology and the applied science of [seabird] conservation are in reality a single continuum of interests and activities. The seabird biologist usually perches somewhere in the middle of this continuum. This person has strong roots in conservation that involve the protection, preservation, restoration, and study of the ecology, physiology, and behavior of seabirds and their populations, no matter which sub-discipline is involved. It behooves us to remain active and committed in the now-well- established activities of seabird study and conservation, the life-blood of PSG itself. KITTLITZ’S AND MARBLED MURRELET STATUS AND TRENDS IN KENAI FJORDS NATIONAL PARK, ALASKA Mayumi Arimitsu*1, John Piatt2, and Tom Van Pelt3, 1U.S. Geological Survey, 3100 National Park Rd, Juneau, AK 99801 USA, [email protected]; 2U.S. Geological Survey, 4210 University Dr., Anchorage, AK 99508 USA; 3U.S. Geological