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RELATIVE CONTRIBUTION OF EUPHAUSIID PREY SPECIES AND TIMING OF BREEDING TO AUKLET GROWTH: WITHIN-SEASON EFFECTS Christine L. Abraham*, Marine Ecology Division, PRBO Conservation Science, 3820 Cypress Drive #11, Petaluma, California, 94954, USA, [email protected] Within-season variation in life-history parameters is characteristic of long-lived seabirds breeding in dynamic marine environments. Zooplanktivorous Cassin’s Auklets (Ptychorhamphus aleuticus) breeding in central California feed primarily on euphausiid crustaceans, and switch from provisioning their offspring primarily with Euphausia pacifica early in the nestling period to Thysanoessa spinifera later in the nestling period. We examined the effects of seasonal variation in auklet parental provisioning (relative diet composition and provisioning mass), and timing of breeding and breeding attempt number (first/only or second breeding attempt) on the growth rate of individual nestlings on Southeast Farallon Island, California. For individual years, there were variable seasonal trends in growth, but no trends were apparent when all years were combined. Overall, there was a seasonal shift in prey use from E. pacifica early to T. spinifera later in the breeding season and a concurrent decrease in provisioning mass. In multivariate models, there were significant and positive effects of E. pacifica, T. spinifera, provisioning mass and breeding attempt number on nestling growth, while the effect of hatching date on growth was negative. The relative influence of T. spinifera on growth was stronger than that of E. pacifica, the effects of hatching date on growth were likely dependent on the effects of breeding attempt, and breeding attempt exerted the strongest effect on nestling growth of all parameters examined. Results provide compelling evidence that relative diet composition, provisioning amount and breeding attempt have positive effects on auklet growth, suggesting that the seasonal switch in prey use is adaptive, and thereby illustrating the importance of adequate availability of both E. pacifica and T. spinifera to auklets in the Gulf of the Farallones. This study represents a unique approach in the investigation of linkages between individual nestling growth rate and diet and breeding phenology parameters by focusing on a fine temporal scale. SUMMER MOVEMENTS OF ´UA´U (HAWAIIAN PETREL PTERODROMA SANDWICHENSIS) NESTING ON HALEAKALĀ, MAUI AND LĀNA´I: CAN WE USE SATELLITE TRACKING TO GAIN NEW INFORMATION AND ADVISE CONSERVATION MANAGEMENT? Josh Adams1,*, David G. Ainley2, Jay F. Penniman3, and Holly B. Freifeld4. 1US Geological Survey, Western Ecological Research Center, Moss Landing Marine Labs, Moss Landing, CA; [email protected] 2H.T. Harvey & Associates, San Jose, CA; 3Hawaii Department of Land & Natural Resources, DOFAW, Pacific Cooperative Studies Unit, University of Hawaii; 4USFWS, Pacific Islands Fish & Wildlife Office, Honolulu, HI. Predation and habitat degradation by non-native species are principal threats to endangered Hawaiian Petrel (´Ua´u, Pterodroma sandwichensis) and threatened Newell’s shearwater (Puffinus auricularis newelli). High priority recovery actions for these seabirds include predator control, habitat restoration, and population monitoring. Required prerequisites for conservation actions include (1) obtaining precise locations of remote, montane nesting areas, (2) refining techniques for population assessment, and (3) identifying at-sea habitat. We report on our ability to use satellite telemetry to track the movements of medium-sized (~400-g) ´Ua´u to help meet these prerequisites for conservation. In summer 2006, we tracked the fine-scale movements of four ´Ua´u: two individuals from separate nest sites provisioning chicks on Lana’i and one parent provisioning a chick and one failed breeder from nest sites on Haleakalā, Maui. Two transmitters were removed after parents completed long (approximately three weeks), clockwise looping foraging trips throughout a broad area of the north Pacific (individual trips can exceed 10,000 km). We discuss the foraging movements of individual ´Ua´u in the context of their pelagic habitat and relate these to what little is known about the species’ at-sea distribution. Tests on Haleakalā, indicate the feasibility of using satellite telemetry techniques in the near future to track the inland movements of both petrels and shearwaters to locate previously undescribed colony locations—an action required for effective management and conservation. Successful use of this technology to track deep diving Newell’s Shearwaters will require modification of existing satellite tag design. TRENDS IN NUMBERS AND DISTRIBUTION OF BREEDING GLAUCOUS-WINGED GULLS (LARUS GLAUCESCENS) AND HYBRID GULLS (L. GLAUCESCENS X L. OCCIDENTALIS) IN THE COLUMBIA RIVER ESTUARY AND PUGET SOUND AREA Jessica Y. Adkins*1, Daniel D. Roby1, and Kirsten Bixler2, 1U.S. Geological Survey-Oregon Cooperative Fish and Wildlife Research Unit, Oregon State University, 104 Nash Hall, Corvallis, OR 97331 USA, [email protected]; 2USGS-Alaska Science Center, Marrowstone Marine Station, 616 Marrowstone Point Rd., Nordland, WA 98358 Numbers of some colonial waterbird species breeding in the Columbia River estuary have increased dramatically during the last two decades (e.g., Caspian Terns [Hydroprogne caspia] and Double- crested Cormorants [Phalacrocorax auritus]). Numbers of breeding Glaucous-winged/Western Gulls in the estuary also have increased substantially, but now appear to be in decline. The Catalog of Washington Seabird Colonies lists 1,750 breeding gulls on East Sand Island in 1982. Counts from aerial photography of nesting hybrid gulls at the same site during the period 1996-2000 ranged from 5,496 to 9,523 individuals. In 2001 this number increased to 12,066 and in 2006, the year of the next aerial count, only 8,587 nesting hybrid gulls were counted. Additionally, we examined numbers and distribution of Glaucous-winged Gull colonies in the greater Puget Sound area to determine the extent of use of anthropogenic colony sites, such as warehouse rooftops, as the use of this habitat by gulls has increased while colonies in natural habitats (e.g., Protection Island NWR) have reportedly been in decline. A total of 9,882 breeding gulls and 3,640 gull nests were counted from aerial photographs taken in June 2006. This is down from the 14,194 breeding gulls listed for a similar area around 1982 in the Washington Seabird Colony Catalog. Although it appears that breeding gulls on dredge spoil islands and urban rooftops in the Puget Sound area has increased by nearly 90% since the early 1980’s, the ca. 60% decline on Protection Island NWR is greater than increases observed at these anthropogenic sites. POINT/COUNTER-POINT? SOME MYTHS AND POINTS SURROUNDING A RE-LISTING PROPOSAL FOR THE CALIFORNIA BROWN PELICAN Daniel W. Anderson*, [email protected]; Dept. of Wildlife, Fish, & Conservation Biology, University of California, Davis, CA 95616 USA It is unclear if there is a distinct point, counter-point argument here. In 1986, PSG proposed a status change for the California brown pelican (Pelecanus occidentalis californicus)(CABRPE). After review, there was hesitancy to act further due to the tentative conservation status in larger populations of the Gulf of California (GC). The CABRPE also acted as a "flagship" species for other seabirds in California. Since, Mexican agencies and NGOs have made significant progress in seabird conservation in the GC. In 2006, the USFWS initiated a new 2006 status review and will soon consider all options for a change in status under the ESA. In essence, there is almost no disagreement from agency and private pelican researchers regarding a change in status (as synthesized by ESRC and supported by PSG), the ultimate decision on specific recommendations should, however be the responsibility of appropriate state and federal agencies, after a thorough review and evaluation of the peer-reviewed scientific data. That ESA special status for the California brown pelican has "undermined" efforts to conserve and manage other species is largely a myth. That recovery of the California brown pelican has been successful is not a myth. Other "myths" and "facts" surrounding the changing conservation status of the CABRPE will be discussed. In contemporary thinking, J. M. Scott et al. (2005) have proposed that conservation efforts after ESA de-listing (and including other sensitive species) treat such entities as "conservation-reliant", still protected, monitored, and managed intensively through various old plus new mechanisms beyond the ESA. I urge PSG to support such progressive conservation. VARIABILITY IN THE PACIFIC DECADAL OSCILLATION INDEX AND DEMOGRAPHY OF A TROPICAL BOOBY David J. Anderson*1, and Howard M. Townsend2, 1Department of Biology, Wake Forest University, Winston-Salem, NC 27109 USA, [email protected]; 2 NOAA Chesapeake Bay Office-Cooperative Oxford Lab, 904 S. Morris Street, Oxford, MD 21654 USA The cyclic Pacific Decadal Oscillation (PDO) has apparent effects on the biology of a number of high latitude organisms, but little evidence exists of similar effects at lower latitudes. We examine a long- term demographic dataset from a pelagic seabird, the Nazca booby (Sula granti), breeding within 150 km of the Equator, for evidence of sensitivity to oceanic variability associated with the PDO. Coincident with a switch in PDO phase from positive to negative in 1998, the diet of Nazca boobies changed from primarily sardines

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