Search results

Title: Seabird bycatch in Alaska demersal longline fishery trials: A demographic summary,
Description: The seasonal and spatial demographics are summarized for seabirds killed incidentally during gear modification trials for a demersal longline fishery in the Bering Sea. We examined 417 carcasses, including Northern Fulmar Fulmarus glacialis (n = 205), Glaucous-winged Gull Larus glaucescens (n = 103), Short-tailed Shearwater Puffinus tenuirostris (n = 48), Glaucous Gull Larus hyperboreus (n = 23), Slaty-backed Gull Larus schistisagus (n = 4), Black-legged Kittiwake Rissa tridactyla (n = 1), Laysan Albatross Diomedea immutabilis (n = 1), and unidentified gull species Larus spp. (n = 32). There was a significant male bias in the sex ratio of fulmars but not of gulls or shearwaters. For the top three species killed, the age composition of resident species was dominated numerically by adults (Northern Fulmar-86%; Glaucous-winged Gull-63%), whereas migrant species were primarily immature birds (Short-tailed Shearwater-71%). The majority of migratory Short-tailed Shearwaters (88%) were caught in July and August, whereas 70% of resident fulmars and gulls were caught in October and November. Age-class frequencies did not differ by month of capture, indicating that adult mortality is substantial. Eighty percent of the fulmars caught during July and August were within 200 km of two colonies in the Bering Sea, whereas only 7% of fulmars were caught in the same area during September to November. This is one of the first demographic summaries of seabird bycatch in Alaska longline fisheries. Additional studies of the species, age and sex of seabirds subject to fisheries-related mortality will provide data necessary to evaluate population-level impacts., Cited By (since 1996):1, ,
Author: Phillips, Nevins, Hatch, Ramey, Miller, Harvey
Date: 2010-01-01T00:00:00Z

Title: Food habits of harbor seals (Phoca vitulina richardii) as an indicator of invasive species in San Francisco Bay, California
Description: The diet of harbor seals (Phoca vitulina richardii) in San Francisco Bay (SFB), California, was determined from July 2007 to July 2008 using prey hard parts recovered from 442 scats collected at five haul-out sites. Twenty-two species of fish and one species of crustacean were identified, but harbor seals primarily ate a nonnative invasive species, yellowfin goby (Acanthogobius flavimanus), which increased in dietary importance since the diet was last studied in 1991/1992. Additionally, another nonnative invasive fish species, chameleon goby (Tridentiger trigonocephalus), was found for the first time in the diet of harbor seals in SFB. Harbor seal diet was statistically different between years (1991/1992 and 2007/2008), between the pupping and nonpupping seasons, and between North SFB and South SFB haul-out locations. The diet of harbor seals was significantly correlated with fish species caught in trawl surveys conducted by the California Department of Fish and Wildlife (CDFW) during the same time periods as this study (2007/2008). Harbor seals currently are influencing the health of the SFB ecosystem in a positive manner by consuming large quantities of nonnative invasive fish species.
Author: Gibble, Harvey

Title: Abundance and distribution of harbor seals (Phoca vitulina) in Oregon, 1975-1983,
Description: , , ,
Author: Harvey, Brown, Mate
Date: 1990-01-01T00:00:00Z

Title: Changes in the cetacean assemblage of a coastal upwelling ecosystem during El Niño 1997-98 and La Niña 1999,
Description: We report results of ecosystem studies in Monterey Bay, California, during the summer upwelling periods, 1996-99, including impacts of El Niño 1997-98 and La Niña 1999. Random-systematic line-transect surveys of marine mammals were conducted monthly from August to November 1996, and from May to November 1997-99. CTDs and zooplankton net tows were conducted opportunistically, and at 10 predetermined locations. Hydroacoustic backscatter was measured continuously while underway to estimate prevalence of zooplankton, with emphasis on euphausiids, a key trophic link between primary production and higher trophic level consumers. The occurrences of several of the California Current's most common cetaceans varied among years. The assemblage of odontocetes became more diverse during the El Niño with a temporary influx of warm-water species. Densities of cold-temperate Dall's porpoise, Phocoenoides dalli, were greatest before the onset of El Niño, whereas warm-temperate common dolphins, Delphinus spp., were present only during the warm-water period associated with El Niño. Rorqual densities decreased in August 1997 as euphausiid backscatter was reduced. In 1998, as euphausiid backscatter slowly increased, rorqual densities increased sharply to the greatest observed values. Euphausiid backscatter further increased in 1999, whereas rorqual densities were similar to those observed during 1998. We hypothesize that a dramatic reduction in zooplankton biomass offshore during El Niño 1997-98 led to the concentration of rorquals in the remaining productive coastal upwelling areas, including Monterey Bay. These patterns exemplify short-term responses of cetaceans to large-scale changes in oceanic conditions. © 2002 Elsevier Science Ltd. All rights reserved., Cited By (since 1996):35, Marine Mammals, Birds & Turtles, CODEN: POCNA, ,
Author: Benson, Croll, Marinovic, Chavez, Harvey
Date: 2002-01-01T00:00:00Z

Title: Impacts of California sea lions and Pacific harbor seals on salmonids in Monterey Bay, California
Author: Harvey, Weise, Stone, Goebel, Webster
Date: 1997-01-01T00:00:00Z

Title: Antarctic research bases,
Description: Contemporary studies of chemical contamination in Antarctica commonly focus on remnants of historical local releases or long-range transport of legacy pollutants. To protect the continent's pristine status, the Antarctic Treaty's Protocol on Environmental Protection prohibits importation of persistent organic pollutants. However, some polybrominated diphenyl ether (PBDE) congeners exhibit similar properties. Many modern polymer-containing products, e.g., home/office furnishings and electronics, contain percent levels of flame retardant PBDEs. PBDE concentrations in indoor dust and wastewater sludge from the U.S. McMurdo and New Zealand-operated Scott Antarctic research bases were high. Levels tracked those in sludge and dust from their respective host countries. BDE-209, the major constituent in the commercial deca-PBDE product, was the dominant congener in sludge and dust, as well as aquatic sediments collected near the McMurdo wastewater outfall. The pattern and level of BDE-209 sediment concentrations, in conjunction with its limited environmental mobility, suggest inputs from local sources. PBDE concentrations in fish and invertebrates nearthe McMurdo outfall rivaled those in urbanized areas of North America and generally decreased with distance. The data indicate that reliance on wastewater maceration alone, as stipulated by the Protocol, may permit entry of substantial amounts of PBDEs and other chemicals to the Antarctic environment. © 2008 American Chemical Society., Cited By (since 1996):48, Antarctica, CODEN: ESTHA, ,
Author: Hale, Kim, Harvey, La Guardia, Mainor, Bush, Jacobs
Date: 2008-01-01T00:00:00Z

Title: State of the California Current 2006-2007: Regional and local processes dominate,
Description: The state of the California Current System (CCS) between Oregon and Baja California is summarized in this report, covering spring 2006 to spring 2007. Observations reported here are based on contributions from various ocean observing programs along the West Coast of North America. Basin-scale indicators were variable or neutral over the last year. This indeterminate forcing was reflected in conditions in the CCS where no coherent patterns emerged, i.e., no single “state” could be ascribed to the system. Rather, regional or local processes dominated observed patterns. Similar to last year, delayed upwelling off Oregon and central California dramatically affected higher trophic levels: euphausiid recruitment was delayed and as a likely consequence seabird productivity off Central California was extremely depressed. For example, Cassin’s auklet had a complete reproductive failure, similar to 2006. Observations during the spring of 2007 demonstrate that these patterns were ephemeral since upwelling was normal and seabird productivity improved. Off southern and Baja California, upwelling-favorable winds were also weak or delayed during 2006, but biological consequences appear to have been relatively minor., Downloaded from: calcofi.org/publications/.../v48/Vol_48_State_Of_California_Current.pdf (2 July 2014)., ,
Author: Goericke, Venrick, Koslow, Sydeman, Schwing, Bograd, Peterson, Emmett, Lara Lara, Castro, Valdez, Hyrenbach, Bradley, Weise, Harvey, Collins, Lo
Date: 2007-01-01T00:00:00Z

Title: Total mercury body burden in Pacific harbor seal, Phoca vitulina richardii, pups from central California
Description: To determine body and tissue compartment-specific burdens (mg) of total mercury (THg), tissues were weighed and analyzed for THg concentration (μg/g fw) in Pacific harbor seal (Phoca vitulina richardii) pups from central California in 2006. THg concentrations were related as follows: hair ≫ liver = kidney = pelt > muscle > other = heart > brain > blubber > bone. THg burden, however, was related as: pelt = muscle > liver = other > kidney = blubber > brain = heart > bone. THg concentration and burden in muscle were strongly associated with δ 15N. δ 13C and δ 15N values were significantly greater in muscle than liver, and δ 13C was significantly lesser the longer animals were in rehabilitation. Because THg concentration and burden in muscle correlated most significantly with other tissue compartments, we recommend that muscle from the specific sites we sampled be used instead of liver or hair for biomonitoring THg in harbor seals. Assessment of proportional THg burdens within each tissue compartment for harbor seals pups included use of a conceptual model, allowing for more complete visual characterization of THg body burden. © 2007 Elsevier Ltd. All rights reserved., Cited By (since 1996):14, Marine Mammals, Birds & Turtles Harbor Seals, CODEN: MPNBA
Author: Brookens, O'Hara, Taylor, Bratton, Harvey
Date: 2008-01-01T00:00:00Z

Title: Seabirds indicate plastic pollution in the marine environment: Quantifying spatial patterns and trends in Alaska
Description: Downloaded from: http://seagrant.uaf.edu/bookstore/pubs/AK-SG-09-01.html (1 August 2014).
Author: Hyrenbach, Nevins, Hester, Keiper, Harvey, Williams, Ammann
Date: 2009-01-01T00:00:00Z

Title: Summer-time use of west coast US National Marine Sanctuaries by migrating sooty shearwaters (Puffinus griseus),
Description: Non-breeding sooty shearwaters are the most abundant seabird in the California Current Large Marine Ecosystem (CCLME) during boreal spring and summer months. This, combined with relatively great energy demands, reliance on patchy, shoaling prey (krill, squid, and forage fishes), and unconstrained mobility free from central-place-foraging demands-make shearwaters useful indicators of ecosystem variability. During 2008 and 2009, we used satellite telemetry to evaluate shearwater ranging patterns throughout the CCLME and specifically within the US Exclusive Economic Zone (EEZ) among birds captured at three locations: Columbia River Plume, WA; Monterey Bay, CA; and Santa Barbara Channel, CA. Shearwaters ranged throughout the entire CCLME from southeast Alaska to southern Baja California, Mexico. Within the EEZ during 2008 and 2009, shearwaters spent 68% and 46% of time over the shelf (<200. m), 27% and 43% of time over the slope (200-1000. m), and 5% and 11% of time over the continental rise and abyssal regions (>1000. m), respectively. In 2008 and 2009, shearwaters spent 22% and 25% of their time in the EEZ within the five west coast National Marine Sanctuaries, respectively; high utilization occurred in non-sanctuary waters of the EEZ. Shearwater utilization distribution (based on the Brownian-bridge movement model) among sanctuaries was disproportionate according to sanctuary availability (based on area) within the EEZ. Shearwaters utilized the Monterey Bay sanctuary (2008, 2009) and the Channel Islands sanctuary (2009) disproportionately more than other sanctuaries. Although all five sanctuaries were used by shearwaters, waters outside sanctuary zones appeared significantly more important and likely supported large aggregations of shearwaters. Utilization distributions among individual birds from three discrete capture locations were variable and revealed greater similarity in space-use sharing within capture-location groupings and during 2008 when shearwaters were more aggregated than in 2009. We identified several regional " habitat hotspot" areas, including the Columbia River Plume, Cape Blanco, Monterey Bay, Estero/San Luis Obispo Bays, and the eastern Santa Barbara Channel through the inner Southern California Bight. © 2012., Cited By (since 1996):1, Marine Mammals, Birds & Turtles, CODEN: BICOB, ,
Author: Adams, MacLeod, Suryan, Hyrenbach, Harvey
Date: 2012-01-01T00:00:00Z

Title: Behavior, movements, and apparent survival of rehabilitated and free-ranging harbor seal pups
Description: Cited By (since 1996):17, Marine Mammals, Birds & Turtles Harbor Seals
Author: Lander, Harvey, Hanni, Morgan
Date: 2002-01-01T00:00:00Z

Title: Adrenal function in wild and rehabilitated pacific harbor seals (Phoca vitulina richardii) and in seals with phocine herpesvirus-associated adrenal necrosis,
Description: Adrenal function in harbor seals (Phoca vitulina richardii) was evaluated using adrenocorticotrophic hormone (ACTH) stimulation tests and fecal cortisol levels. The effect of ACTH administration on plasma cortisol and aldosterone levels in five free-living and 14 rehabilitated harbor seal pups was determined using enzyme immunoassay and radioimmunoassay, respectively. In free-living seals, injection of ACTH caused a significant increase in mean plasma cortisol but not of mean aldosterone levels 60 min postinjection. In these seals, mean initial plasma aldosterone was significantly higher than initial levels in rehabilitated seals, while initial cortisol levels were similar. Of the rehabilitated seals, eight died with adrenal cortical necrosis associated with herpesvirus inclusions, while six lived to be released. In the seals that were released, both mean initial cortisol levels and response to ACTH decreased through rehabilitation. In the seals that died, mean initial cortisol and response to ACTH increased through rehabilitation. The differences between initial cortisol levels in seals that lived and those that died were significant at weeks two and four of rehabilitation but not at the week of admission. There was considerable individual variation in initial plasma aldosterone levels and responses to ACTH, although initial aldosterone levels were significantly higher in rehabilitated seals that died than in seals that lived. Seals with adrenal necrosis associated with herpesvirus infection did not have decreased adrenal hormone responses to ACTH. Differences between initial hormone levels and responses to ACTH in different groups of seals may be associated with differing stress levels. Fecal cortisol assays were not a useful method of assessing adrenal function in these seals, as measured levels did not correlate with plasma cortisol levels., Cited By (since 1996):13, CODEN: MMSCE, , , Marine Mammals, Birds & Turtles
Author: Gulland, Haulena, Lowenstine, Munro, Graham, Bauman, Harvey
Date: 1999-01-01T00:00:00Z

Title: Pupping-site fidelity among individual Steller sea lions (Eumetopias jubatus) at Chiswell Island, Alaska
Description: Pupping-site fidelity (defined as pupping within 5.8 m of a previous location in ≥2 years) in Steller sea lions (Eumetopias jubatus (Schreber, 1776)) was investigated during the breeding seasons from 2001 to 2005 at Chiswell Island, a small rookery in the Gulf of Alaska. Density of females was minimal with 54-80 pups born. Photo-identification of individuals and GPS points, including elevation of the rookery, were used to determine locations of 297 births. Sixty-four percentage (35/55) of the females exhibited pupping-site fidelity, and mean frequency of site fidelity was greater for females that gave birth >3 times. Fifty percentage of the births occurred at 22% of the locations for all years, indicating that multiple births occurred at some locations throughout the breeding season. Competition or aggression among females for specific pupping locations before birth was not observed, and there was no temporal order of pupping locations used, indicating that the rookery was not overcrowded and that many suitable pupping locations existed. Multiparous females gave birth at significantly greater distances from the surf zone than primiparous females. Long-term monitoring of pupping-site fidelity in combination with other measures of maternal care will ultimately determine which factors have the greatest effect on pup survival. © 2008 NRC., Cited By (since 1996):1, CODEN: CJZOA
Author: Parker, Harvey, Maniscalco, Atkinson
Date: 2008-01-01T00:00:00Z

Title: Juvenile mortality in gray whales (Eschrichtius robustus),
Description: , , ,
Author: Sumich, Harvey
Date: 1986-01-01T00:00:00Z

Title: Acoustic evidence that harbor porpoises (Phocoena phocoena) avoid bottlenose dolphins (Tursiops truncatus)
Author: Jacobson, Forney, Harvey

Title: Geography and stage of development affect persistent organic pollutants in stranded and wild-caught harbor seal pups from central California,
Description: Persistent organic pollutants have been associated with disease susceptibility and decreased immunity in marine mammals. Concentrations of polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane and its metabolites (DDTs), polybrominated diphenyl ethers (PBDEs), chlordanes (CHLDs), and hexachlorocyclohexane isomers (HCHs) were evaluated in terms of stage of development and likely exposure routes (in utero, suckling, fasting) in the blubber of 202 stranded and wild-caught, primarily young of the year (n = 177), harbor seals (Phoca vitulina) in the central California coast. This is the first report of HCH concentrations in the blubber of California seals. Lipid normalized concentrations ranged from 200 to 330,000. ng/g for sum PCBs, 320-1,500,000. ng/g for sum DDTs, 23-63,000. ng/g for sum PBDEs, 29-29,000. ng/g for sum CHLDs, and 2-780. ng/g for sum HCHs. The highest concentrations were observed in harbor seal pups that suckled in the wild and then lost mass during the post-weaning fast. Among the pups sampled in the wild and those released from rehabilitation, there were no differences in mass, blubber depth, or percent lipid although contaminant concentrations were significantly higher in the pups which nursed in the wild. When geographic differences were evaluated in a subset of newborn animals collected near their birth locations, the ratio of sum DDTs to sum PCBs was significantly greater in samples from an area with agricultural inputs (Monterey), than one with industrial inputs (San Francisco Bay). A principal components analysis distinguished between seals from San Francisco Bay and Monterey Bay based on specific PCB and PBDE congeners and DDT metabolites. These data illustrate the important influence of life stage, nutritional status, and location on blubber contaminant levels, and thus the need to consider these factors when interpreting single sample measurements in marine mammals. © 2011 Elsevier B.V., Cited By (since 1996):6, CODEN: STEVA, ,
Author: Greig, Ylitalo, Wheeler, Boyd, Gulland, Yanagida, Harvey, Hall
Date: 2011-01-01T00:00:00Z

Title: Characterization of a harbor seal class I major histocompatability complex cDNA clone,
Description: Cited By (since 1996):1, Marine Mammals, Birds & Turtles, CODEN: IMNGB, , ,
Author: Zhong, Harvey, Boothby
Date: 1998-01-01T00:00:00Z

Title: A captive feeding study with the Pacific harbor seal (Phoca vitulina richardii),
Description: Seven prey species (ntotal > 2,700) were fed to seven captive male Pacific harbor seals (Phoca vitulina richardii) in 177 experimental meals to quantify biases associated with scat analysis and current consumption models. Hard parts from an individual meal were recovered in an average of 3.8 ± 1.8 scats (range 1-10; mean ± SD). Overall, 57.7 ± 33.2% of otoliths and 89.5 ± 15.5% of squid beaks were recovered. Recovery rates varied, and prey with smaller, fragile otoliths were recovered in lesser quantities than prey with larger, robust otoliths. Recovery rates of all prey except pink salmon were improved by a mean of 31.7% when all diagnostic structures were included in estimates. Estimated recovery of pink salmon was 9.5 times that fed seals based on the all-structure technique. Mean length reduction of recovered otoliths was 20.4 ± 10.1%. Correction factors calculated from average length reduction improved length estimates for all fish species. Grade-specific length correction factors (gLCFs) reduced variability in all of the estimates and significantly improved estimates of prey with highly eroded otoliths including Pacific hake and shortbelly rockfish. The Biomass Reconstruction (BR) model accurately predicted biomass consumption within 4% of known consumption, whereas estimates based on frequency of occurrence were inaccurate. © 2009 by the Society for Marine Mammalogy., Cited By (since 1996):8, Marine Mammals, Birds and Turtles, CODEN: MMSCE, ,
Author: Phillips, Harvey
Date: 2009-01-01T00:00:00Z

Title: Food habits of harbor seals inhabiting Elkhorn Slough, California,
Description: , , ,
Author: Harvey, Helm, Morejohn
Date: 1995-01-01T00:00:00Z

Title: An outbreak of probable leptospirosis in California sea lions along the Oregon coast during fall 1984,
Description: Cited By (since 1996):1, Export Date: 23 May 2014, , , ,
Author: Hodder, Harvey, Graybill, Brown, Ebberts
Date: 1992-01-01T00:00:00Z

Title: The feasibility and effectiveness of using an acoustic barrier to restrict the movements of seals into Netarts Bay, Oregon
Author: Harvey, Mate, Brown, Mate, Harvey
Date: 1987-01-01T00:00:00Z

Title: Post-release monitoring and tracking of a rehabilitated California gray whale,
Description: We developed surface-mounted, buoyant housings for VHF and UHF (satellite-linked) radio-transmitters for attachment to a rehabilitated gray whale calf (JJ). We then used those devices to track her for several days after her return to the Pacific Ocean on 31 March 1998. The instruments came off within three days, evidently owing to shallow and incomplete seating of the barb and toggle anchors placed in the blubber layer and from JJ rubbing against the sea bottom when attempting to feed. Nonetheless, the instruments performed exceptionally well during the brief tracking period and the buoyant design allowed us to recover them using radio signals detected by boat-based observers, and shore-based crews, and by earth-orbiting satellites. Secure, reliable attachment methods that will not compromise the health and vitality of cetaceans remain the key substantive issue for advancing studies of long-term movements and behavior baleen whales., , ,
Author: Stewart, Harvey, Yochem
Date: 2000-01-01T00:00:00Z

Title: A mass stranding of sperm whales in Oregon,
Description: , , , A school of 41 sperm whales, Physeter macrocephalus, that stranded near the mouth of the Siuslaw River, Oregon (43°59’N, 124°08’W), on 16 June 1979 consisted of 13 males and 28 females. Their ages were estimated by assuming that each postnatal dentin layer represents one year. The males were all subadults, 9.3-11.5 m long and 14-21 yr old. The females were 9.3-11.4 m long, and 11 to about 58 yr old. Ten females were dissected; nine were sexually mature and three were carrying fetuses 2.64-4.62 m long. None of the 28 females was visibly lactating., ,
Author: Rice, Wolman, Mate, Harvey
Date: 1986-01-01T00:00:00Z

Title: Preliminary studies on the age and growth of blue (Prionace glauca), common thresher (Alopias vulpinus), and shortfin mako (Isurus oxyrinchus) sharks from California waters
Description: Two methods of enhancing growth bands on vertebral centra-silver nitrate impregnation and X -radiography have proven to be successful when used on centra from 130 blue, Prionace glauca, 143 common thresher, Alopias vulpinus, and 44 shortfin maim, Isurus oxyrinchus, sharks. Bands were counted and measured, and these data were used to construct growth curves based on the von Bertalanffy and logistic growth models. The problems of verification of these counts, and validation of the periodicity of band formation, have been identified and are discussed in relation to the growth curves generated for each of these three species. Our results and other available information indicate that these elasmobranchs grow relatively slowly, reaching their asymptotic lengths at 20 yr of age for blue sharks, and between 45 and 50 yr for shortfin mako and common thresher sharks. They have a large size but relatively early age of ilrst reproductive maturity, and low fecundities. This combination of traits could make them susceptible to overfishing.
Author: Cailliet, Martin, Harvey, Kusher, Welden, Prince, Pulos
Date: 1983-01-01T00:00:00Z

Title: Abundance and distribution of marine mammals in nearshore waters of Monterey Bay, California,
Description: We studied the seasonal abundance and spatial distribution of marine mammals in nearshore waters (<1 km from shore) of Monterey Bay, California, during 1999 and 2000. The most abundant mammal was California sea lion, Zalophus californianus, followed by harbor porpoise, Phocoena phocoena, sea otter, Enhydra lutris, and harbor seal, Phoca vitulina. Seasonal abundance of harbor porpoise in the survey area was greatest during winter, pinnipeds were most abundant during autumn, and sea otters were most abundant during spring and autumn. California sea lions were more abundant in 2000 than in 1999. Harbor porpoise were found in water of lesser clarity than expected by chance, and sea lions were found more often in water of intermediate clarity. Distribution of sea otters and harbor seals were not affected by water clarity., Cited By (since 1996):2, , , Marine Mammals, Birds & Turtles
Author: Henkel, Harvey
Date: 2008-01-01T00:00:00Z

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