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Title: Marine mammal response to interannual variability in Monterey Bay, California
Description: The coastal upwelling ecosystem near Monterey Bay, California, is a productive yet variable ecosystem and an important foraging area for many mobile apex predators, such as marine mammals. Long-term studies are necessary to better understand how wide-ranging predators respond to temporal environmental variability; however, few of these studies exist. We conducted monthly shipboard line-transect surveys in Monterey Bay from 1997 to 2007. We identified 22 species of marine mammals, and calculated monthly and annual densities for the 12 most commonly sighted (focal) species. Species richness remained relatively constant (mean richness ± SE: 13.7 ± 0.396 species yr -1) from 1997 to 2006. Focal species were most evenly distributed (Shannon's equitability, E H = 0.820) but least dense (mean density ± SE: 0.0598 ± 0.0141) during the anomalous upwelling conditions of 2005, and least even (1997 E H = 0.413; 1998 E H = 0.407) but dense (mean density ± SE: 1997: 0.433 ± 0.177; 1998: 0.438 ± 0.169 ind. km -2) during the 1997/1998 El Niño event. There were no statistically significant differences in the densities of marine mammal species between warmer and cooler years. The community and species-specific responses of marine mammals to warm-water years differed depending on the mechanism of oceanographic variability. During the 1997/1998 El Niño (a basin-wide event), marine mammals aggregated in nearshore areas, such as Monterey Bay, with relatively greater productivity than offshore regions, whereas during anomalous upwelling conditions of 2005 (a more localized oceanographic event), marine mammals redistributed away from Monterey Bay to areas less affected by the anomaly. © Inter-Research 2012, Export Date: 24 September 2013
Author: Burrows, Harvey, Newton, Croll, Benson
Date: 2012-01-01T00:00:00Z

Title: The transmission of phocine herpesvirus-1 in rehabilitating and free-ranging Pacific harbor seals (Phoca vitulina) in California,
Description: Phocine herpesvirus-1 (PhHV-1) causes regular outbreaks of disease in neonatal harbor seals (Phoca vitulina) at rehabilitation centers in Europe and in the U.S. To investigate transmission of this virus samples were collected from harbor seal pups during exposure studies at a Californian rehabilitation center from 1999 to 2002 and from free-ranging harbor seals off central California during the same period. The exposure studies provided evidence that PhHV-1 can be transmitted horizontally between animals most likely through direct contact with oro-nasal secretions. However vertical transmission may also occur, as adult female harbor seals were found to be shedding the virus in vaginal and nasal secretions, and premature newborn pups had evidence of early infection. Results also indicated that PhHV-1 infections were common in both free-ranging (40%, 49/121) and rehabilitating (54%, 46/85) young harbor seals, during the spring and early summer. This timing, which correlated with pupping and weaning, suggested that the majority of animals were infected and infective with PhHV-1 between pupping and breeding. © 2004 Elsevier B.V. All rights reserved., Cited By (since 1996):9, Marine Mammals, Birds & Turtles, CODEN: VMICD, ,
Author: Goldstein, Mazet, Gulland, Rowles, Harvey, Allen, King, Aldridge, Stott
Date: 2004-01-01T00:00:00Z

Title: Internesting movements and behavior of hawksbill turtles (Ertemochelys imbricata) around Buck Island Reef National Monument, St. Croix, U.S. Virgin Islands
Author: Starbird, Hillis-Starr, Harvey, Eckert

Title: Entanglements of marine mammals and seabirds in central California and the north-west coast of the United States 2001-2005,
Description: Entanglement records for seabirds and marine mammals were investigated for the period 2001-2005. The entanglement records were extracted from databases maintained by seven organizations operating along the west coast of the United States of America. Their programmes included beach monitoring surveys, rescue and rehabilitation and regional pinniped censuses. Records of 454 entanglements were documented in live animals and in carcasses for 31 bird species and nine marine mammal species. The most frequently entangled species were Common Murres, Western Gulls and California sea lions. The entanglement materials identified were primarily fishing related. Entanglements were recorded every year suggesting that although the incidence level differs annually, entanglement is a persistent problem. It is recommended that each programme records details in standardized categories to determine entanglement material sources. Numbers of entanglements observed during these surveys are likely to be a conservative view of the actual entanglement rate taking place at sea. © 2009 Elsevier Ltd., Cited By (since 1996):9, Marine Mammals, Birds & Turtles, CODEN: MPNBA, ,
Author: Moore, Lyday, Roletto, Litle, Parrish, Nevins, Harvey, Mortenson, Greig, Piazza, Hermance, Lee, Adams, Allen, Kell
Date: 2009-01-01T00:00:00Z

Title: Antibodies to phocine herpesvirus-1 are common in North American harbor seals (Phoca Vitulina),
Description: Phocine herpesvirus-1 (PhHV-1) has been associated with morbidity and high mortality in neonatal harbor seals (Phoca vitulina) along the Pacific coast of California (USA) and in northern Europe. Seals dying with PhHV-1 associated disease in California primarily have histopathologic evidence of adrenal necrosis or adrenalitis with herpesviral inclusion bodies. Little is known about prevalence of exposure to PhHV-1, modes of disease transmission, and viral pathogenesis in free-ranging harbor seal populations. To evaluate the prevalence in North America, 866 serum samples collected between 1994 and 2002 from harbor seals captured or stranded on the Pacific and Atlantic coasts of North America were assayed by enzyme linked immunosorbent assay (ELISA) for evidence of PhHV-1 exposure. Samples from three harbor seal age classes (pre-weaned, weaned, and subadults/adults) were obtained from each of four regions to compare exposure among sex, age class, and region. We found increasing prevalence with age as 37.5% of pre-weaned pups, 87.6% of weaned pups, and 99.0% of subadults and adults were seropositive. When accounting for age, no associations between seropositivity and sex or location of harbor seals were detected. These data indicate that PhHV-1 is endemic in the harbor seal populations of North America. © Wildlife Disease Association 2003., Cited By (since 1996):7, Marine Mammals, Birds & Turtles, ,
Author: Goldstein, Gulland, Aldridge, Harvey, Rowles, Lambourn, Jeffries, Measures, Yochem, Stewart, Small, King, Stott, Mazet
Date: 2003-01-01T00:00:00Z

Title: PCB and DDE contamination in harbor seals (Phoca vitulina) from North-Central California and Bristol Bay, Alaska,
Description: In recent years, concerns have increased regarding accumulation of persistent, lipophilic contaminants by marine mammals. We quantified blood levels of the two most prevalent organochlorine (OC) contaminants of the marine ecosystem in a model species, the harbor seal (Phoca vitulina) from three north-central California populations and a population in Bristol Bay, Alaska. Intensive sampling (n = 190) produced robust quantification of blood concentrations of selected PCBs and DDE, and allowed us to investigate factors affecting levels of these contaminants in seal populations with distinct environments and exposure histories. In the Alaskan samples, PCB and DDE levels were most strongly related to sex and age; OCs increased with age in males and decreased with age in females, likely due to cumulative exposure in males and load-dumping during lactation in females. Among females, an inverse relationship was observed between condition and PCB blood levels. In contrast, in the California seals, in which loads were generally much greater, pups had greater levels of PCBs and DDE than subadults and adults, suggesting stable to decreasing environmental contaminant levels. Spatial heterogeneity and seasonal differences also contributed substantially to variation among harbor seals in contaminant loads. These findings underscore the importance of accounting for demographic, geographic, seasonal, and physiological effects in toxicological studies of marine mammals., Cited By (since 1996):1, ,
Author: Neale, Schmelzer, Harvey, Berg, Small, Grigg, Allen, Tjeerderma
Date: 2009-01-01T00:00:00Z

Title: Corrigendum to "Total mercury body burden in Pacific harbor seal, Phoca vitulina richardii, pups from central California"
Description: Marine Mammals, Birds & Turtles Harbor Seals, CODEN: MPNBA
Author: Brookens, O'Hara, Taylor, Bratton, Harvey
Date: 2009-01-01T00:00:00Z

Title: Movement, dive behavior, and survival of California sea lions (Zalophus californianus) posttreatment for domoic acid toxicosis
Description: Domoic acid (DA) is a neuroexcitatory toxin increasingly causing strandings and mortality of marine mammals. The hippocampus of mammalian brains, associated with learning, memory, and spatial navigation, is one of the predominant regions affected by DA exposure. California sea lions stranding from 2003 to 2006 as a result of DA toxicosis were classified as having acute (n = 12) or chronic neurologic (n = 22) clinical signs. Chronic neurologic cases were examined by magnetic resonance imaging to determine the extent of brain damage related to DA exposure. Brain damage included hippocampal and parahippocampal atrophy, temporal horn enlargement, and pathological T2 hyperintensity. Posttreatment, animals were fitted with satellite transmitters and their movement and dive behaviors compared with those of a control group. The only significant difference between acute and chronic animals was distance traveled per day. There were, however, significant differences between chronic neurologic cases and controls: chronic neurologic cases dove shallower for shorter durations, traveled further from shore, and spent less time hauled out and more time surface swimming than control animals. There was no relationship between severity of brain damage and behavioral patterns for chronic neurologic cases. Sea lions with chronic neurologic changes had a poor prognosis for survival following release. © 2009 by the Society for Marine Mammalogy., Cited By (since 1996):6, CODEN: MMSCE
Author: Thomas, Harvey, Goldstein, Barakos, Gulland

Title: Potential prey resources for Marbled Murrelets in central California
Description: Information on the diet of the Marbled Murrelet, Brachyramphus marmoratus, in California is lacking. To assess availability of potential prey, we sampled small fishes at three locations in central California: Año Nuevo Bay, and two sites in northern Monterey Bay. These sites are used seasonally by Marbled Murrelets. Nearshore marine habitats were sampled with a midwater trawl during 2000, 2001, and 2002. We caught 36 taxa of demersal and midwater fish and cephalopods. Numerically dominant species at all sites were northern anchovy, Engraulis mordax, night smelt, Spirinchus starski, and white croaker, Genyonomus lineatus. The occurrence of these fishes concurrent with Marbled Murrelets provides information on potential prey available to Marbled Murrelets in central California., Cited By (since 1996):3
Author: Henkel, Harvey

Title: Proliferative responses of harbor seal (Phoca vitulina) T lymphocytes to model marine pollutants,
Description: In recent years, population declines related to viral outbreaks in marine mammals have been associated with polluted coastal waters and high tissue concentrations of certain persistent, lipophilic contaminants. Such observations suggest a contributing role of contaminant-induced suppression of cell-mediated immunity leading to decreased host resistance. Here, we assessed the effects of the prototypic polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (B[a]P), and two polychlorinated biphenyls (PCBs), CB-156 and CB-80, on the T-cell proliferative response to mitogen in harbor seal peripheral lymphocytes. Despite the variability associated with our samples from free-ranging harbor seals, we observed a clear suppressive effect of B[a]P (10 uM) exposure on T cell mitogenesis. Exposures to 10 uM CB-156 and CB-80, and 1.0 and 0.1 uM B[a]P, did not produce significant depression in lymphoproliferation. Exposure to the model PAH at 10 uM resulted in a 61% (range 34-97%) average reduction in lymphoproliferation. We were able to rule out a direct cytotoxic effect of B[a]P, indicating that observed effects were due to altered T cell function. Based on our in vitro results, we hypothesize that extensive accumulation of PAH by top-trophic-level marine mammals could alter T cell activation in vivo and impaired cell-mediated immunity against viral pathogens., Cited By (since 1996):12, CODEN: DEIME, ,
Author: Neale, Van De Water, Harvey, Tjeerdema, Gershwin
Date: 2002-01-01T00:00:00Z

Title: Marine mammal occurrence and ocean climate off central California, 1986 to 1994 and 1997 to 1999,
Description: The California Current System (CCS), a highly variable eastern boundary system, supports a rich marine mammal fauna. Variation in local coastal upwelling, coupled with larger scale processes (El Niño/La Niña) affects the productivity and distribution of marine species at all trophic levels. Herein, we present an analysis of the occurrence patterns of marine mammals in the central CCS and relate these patterns to changing ocean climate and prey availability. Data on marine mammal distributions, ocean conditions, and prey availability were collected in waters overlying the continental shelf and slope from Bodega to Monterey Bays, from 1986 to 1994 and 1997 to 1999. Occurrence patterns were investigated using geographical information system (GIS), percent similarity index (PSI), multiple logistic regression, and principal component analyses. Spatial patterns of the most frequently sighted species (California sea lion Zalophus californianus, northern fur seal Callorhinus ursinus, Pacific white-sided dolphin Lagenorhyncus obliquidens, Dall's porpoise Phocoenoides dalli, harbor porpoise Phocoena phocoena, and humpback whale Megaptera novaeangliae) were related to bathymetry and changing ocean climate, and were likely to have been mediated by changes in prey availability. Temporal changes were related to migration and significant differences in ocean structure resulting from both local and large-scale processes., Cited By (since 1996):21, CODEN: MESED, , , Downloaded from:www.int-res.com/articles/meps2005/289/m289p285.pdf (9 June 2014).
Author: Keiper, Ainley, Allen, Harvey
Date: 2005-01-01T00:00:00Z

Title: Stable carbon and nitrogen isotopes in multiple tissues of wild and captive harbor seals (Phoca vitulina) off the California coast
Description: Stable carbon and nitrogen isotope ratios (δ13C and δ15N) of serum, red blood cells (RBC), muscle, and blubber were measured in captive and wild northeast Pacific harbor seals (Phoca vitulina richardii) at three coastal California sites (San Francisco Bay, Tomales Bay, and Channel Islands). Trophic discrimination factors (ΔTissue-Diet) were calculated for captive seals and then applied in wild counterparts in each habitat to estimate trophic position and feeding behavior. Trophic discrimination factors for δ15N of serum (+3.8‰), lipid-extracted muscle (+1.6‰), and lipid-blubber (+6.5‰) are proposed to determine trophic position. An offset between RBC and serum of +0.3‰ for δ13C and -0.6‰ for δ15N was observed, which is consistent with previous research. Specifically, weaner seals (<1 yr) had large offsets, suggesting strong trophic position shifts during this life stage. Isotopic values indicated an average trophic position of 3.6 at both San Francisco Bay and Tomales Bay and 4.2 at Channel Islands. Isotopic means were strongly dependent on age class and also suggested that mean diet composition varies considerably between all locations. Together, these data indicate that isotopic composition of blood fractions can be an effective approach to estimate trophic position and dietary behavior in wild pinnipeds. © 2011 by the Society for Marine Mammalogy., Cited By (since 1996):1, Marine Mammals, Birds & Turtles, CODEN: MMSCE
Author: Germain, McCarthy, Koch, Harvey

Title: The 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., Cited By (since 1996):24, Ecology, ,
Author: Goericke, Venrick, Koslow, Sydeman, Schwing, Bograd, Emmett, Peterson, Rubén Lara Lara, Castro, José, Hyrenbach, Bradley, Weise, Harvey, Collins, Lo
Date: 2007-01-01T00:00:00Z

Title: Impact of the California sea lion (Zalophus californianus) on salmon fisheries in Monterey Bay, California,
Description: To assess the impact of California sea lions (Zalophus californianus) on salmon fisheries in the Monterey Bay region of California, the percentages of hooked fish taken by sea lions in commercial and recreational salmon fisheries were estimated from 1997 to 1999. Onboard surveys of sea lion interactions with the commercial and recreational fisheries and dockside interviews with fishermen after their return to port were conducted in the ports of Santa Cruz, Moss Landing, and Monterey. Approximately 1745 hours of onboard and dockside surveys were conducted - 924 hours in the commercial fishery and 821 hours in the recreational fishery (commercial passenger fishing vessels [CPFVs] and personal skiffs combined). Adult male California sea lions were responsible for 98.4% of the observed depredations of hooked salmon in the commercial and recreational fisheries in Monterey Bay. Mean annual percentages of hooked salmon taken by sea lions ranged from 8.5% to 28.6% in the commercial fishery, 2.2% to 18.36% in the CPFVs, and 4.0% to 17.5% in the personal skiff fishery. Depredation levels in the commercial and recreational salmon fisheries were greatest in 1998 - likely a result of the large El Niño Southern Oscillation (ENSO) event that occurred from 1997 to 1998 that reduced natural prey resources. Commercial fishermen lost an estimated $18,031-$60,570 of gear and $225,833-$498,076 worth of salmon as a result of interactions with sea lions. Approximately 1.4-6.2% of the available salmon population was removed from the system as a result of sea lion interactions with the fishery. Assessing the impact of a growing sea lion population on fisheries stocks is difficult, but may be necessary for effective fisheries management., Cited By (since 1996):9, CODEN: FSYBA, ,
Author: Weise, Harvey
Date: 2005-01-01T00:00:00Z

Title: Characterizing dispersal patterns in a threatened seabird with limited genetic structure,
Description: Genetic assignment methods provide an appealing approach for characterizing dispersal patterns on ecological time scales, but require sufficient genetic differentiation to accurately identify migrants and a large enough sample size of migrants to, for example, compare dispersal between sexes or age classes. We demonstrate that assignment methods can be rigorously used to characterize dispersal patterns in a marbled murrelet (Brachyramphus marmoratus) population from central California that numbers approximately 600 individuals and is only moderately differentiated (FST∼ 0.03) from larger populations to the north. We used coalescent simulations to select a significance level that resulted in a low and approximately equal expected number of type I and II errors and then used this significance level to identify a population of origin for 589 individuals genotyped at 13 microsatellite loci. The proportion of migrants in central California was greatest during winter when 83% of individuals were classified as migrants compared to lower proportions during the breeding (6%) and post-breeding (8%) seasons. Dispersal was also biased toward young and female individuals, as is typical in birds. Migrants were rarely members of parent-offspring pairs, suggesting that they contributed few young to the central California population. A greater number of migrants than expected under equilibrium conditions, a lack of individuals with mixed ancestry, and a small number of potential source populations (two), likely allowed us to use assignment methods to rigorously characterize dispersal patterns for a population that was larger and less differentiated than typically thought required for the identification of migrants. © 2009 Blackwell Publishing Ltd., Cited By (since 1996):11, Marine Mammals, Birds & Turtles, CODEN: MOECE, ,
Author: Hall, Palsbøll, Beissinger, Harvey, Bérubé, Raphael, Nelson, Golightly, McFarlane-Tranquilla, Newman, Peery
Date: 2009-01-01T00:00:00Z

Title: Prey and plastic ingestion of Pacific Northern Fulmars (Fulmarus glacialis rogersii) from Monterey Bay, California
Description: Marine plastic pollution affects seabirds, including Pacific Northern Fulmars (Fulmarus glacialis rodgersii), that feed at the surface and mistake plastic for prey or incidentally ingest it. Direct and indirect health issues can result, including satiety and possibly leading to inefficient foraging. Our objective was to examine fulmar body condition, identify cephalopod diet to species, enumerate and weigh ingested plastic, and determine if prey number and size were correlated with ingested plastics in beach-cast fulmars wintering in Monterey Bay California (2003, n= 178: 2007, n= 185). Fulmars consumed mostly Gonatus pyros, G. onyx, and G. californiensis of similar size for both years. We found a significant negative correlation between pectoral muscle index and average size of cephalopod beaks per stomach; a significant increase in plastic categories between 2003 and 2007; and no significant correlation between number and mass of plastic compared with number and size of prey for either year. © 2014 Elsevier Ltd.
Author: Donnelly-Greenan, Harvey, Nevins, Hester, Walker

Title: Surveillance for zoonotic and selected pathogens in harbor seals phoca vitulina from central California
Description: The infection status of harbor seals Phoca vitulina in central California, USA, was evaluated through broad surveillance for pathogens in stranded and wild-caught animals from 2001 to 2008, with most samples collected in 2007 and 2008. Stranded animals from Mendocino County to San Luis Obispo County were sampled at a rehabilitation facility: The Marine Mammal Center (TMMC, n = 175); wild-caught animals were sampled at 2 locations: San Francisco Bay (SF, n = 78) and Tomales Bay (TB, n = 97), that differed in degree of urbanization. Low prevalences of Salmonella, Campylobacter, Giardia, and Cryptosporidium were detected, in the feces of stranded and wild-caught seals. Clostridium perfringens and Escherichia coli were more prevalent in the feces of stranded (58% [78 out of 135] and 76% [102 out of 135]) than wild-caught (42% [45 out of 106] and 66% [68 out of 106]) seals, whereas Vibrio spp. were 16 times more likely to be cultured from the feces of seals from SF than TB or TMMC (p < 0.005). Brucella DNA was detected in 3.4% of dead stranded harbor seeds (2 out of 58). Type A influenza was isolated from feces of 1 out of 96 wild-caught seals. Exposure to Toxoplasma gondii, Sarcocystis neurona, and type A influenza was only detected in the wild-caught harbor seals (post-weaning age classes), whereas antibody titers to Leptospira spp. were detected in stranded and wild-caught seals. No stranded (n = 109) or wild-caught (n = 217) harbor seals had antibodies to phocine distemper virus, although a single low titer to canine distemper virus was detected. These results highlight the role of harbor seals as sentinel species for zoonotic and terrestrial pathogens in the marine environment., Harbor Seals
Author: Greig, Gulland, Smith, Conrad, Field, Fleetwood, Harvey, Ip, Jang, Packham, Wheeler, Hall

Title: An acoustic harassment technique to reduce seal predation on salmon
Author: Mate, Brown, Greenlaw, Harvey, Temte, Mate, Harvey
Date: 1987-01-01T00:00:00Z

Title: Survival probabilities and movements of harbor seals in central California
Description: Article in Press, Harbor seal numbers and population trajectories differ by location in central California. Within San Francisco Bay (SFB) counts have been relatively stable since the 1972 Marine Mammal Protection Act, but in coastal areas like Tomales Bay (TB), counts increased before stabilizing in the 1990s. Emigration, poor survival, and environmental effects have been hypothesized as contributors to differences between trajectories; however, basic demographic data were not available to evaluate these hypotheses. We monitored 32 radio-tagged adult females (SFB n = 17, TB n = 15) for 20 mo (2011-2013), and estimated survival, resight, and movement probabilities using mark-resight analyses and multistate mark-resight models. Annual survival probability for both sites was 0.90 (95% CI = 0.18-0.99). Six seals were observed moving between locations resulting in an estimated probability of 0.042 (95% CI = 0.023-0.076) per month equal movement between sites. Resight probability was less in SFB relative to TB, likely due to differential haul-out access, area surveyed, visibility, and resight effort. Because of wide confidence intervals and low precision of these first estimates of adult female harbor seal survival in California, this demographic must be further examined to dismiss its contribution to differing population trajectories. Using aerial survey data, we estimated 950 harbor seals in SFB (95% CI = 715-1,184) confirming numbers are still stable.
Author: Manugian, Greig, Lee, Becker, Allen, Lowry, Harvey

Title: Recovery rates of bottlenose dolphin (Tursiops truncatus) carcasses estimated from stranding and survival rate data
Description: Recovery of cetacean carcasses provides data on levels of human-caused mortality, but represents only a minimum count of impacts. Counts of stranded carcasses are negatively biased by factors that includes at-sea scavenging, sinking, drift away from land, stranding in locations where detection is unlikely, and natural removal from beaches due to wave and tidal action prior to detection. We estimate the fraction of carcasses recovered for a population of coastal bottlenose dolphins (Tursiops truncatus), using abundance and survival rate data to estimate annual deaths in the population. Observed stranding numbers are compared to expected deaths to estimate the fraction of carcasses recovered. For the California coastal population of bottlenose dolphins, we estimate the fraction of carcasses recovered to be 0.25 (95% CI = 0.20-0.33). During a 12 yr period, 327 animals (95% CI = 253-413) were expected to have died and been available for recovery, but only 83 carcasses attributed to this population were documented. Given the coastal habits of California coastal bottlenose dolphins, it is likely that carcass recovery rates of this population greatly exceeded recovery rates of more pelagic dolphin species in the region.
Author: Caretta, Danil, Chivers, Weller, Janiger, Berman-Kowalewski, Hernandez, Harvey, Dunkin, Casper, Stoudt, Flannery, Wilkinson, Huggins, Lambourn

Title: Effects of rapid flight-feather molt on postbreeding dispersal in a pursuit-diving seabird,
Description: Breeding seabirds have been well studied but seabird ecology during the nonbreeding season is poorly understood because many species disperse far from breeding colonies to molt at sea. We characterized the timing of prebasic molt and postbreeding dispersal, described postbreeding dispersal movements, and estimated changes in body mass during molt for Marbled Murrelets (Brachyramphus marmoratus; Alcidae) in central California, 1999-2004. According to mark-recapture and at-sea surveys, 248-315 of 496-637 individuals (43-50%) used Año Nuevo Bay, located immediately adjacent to nesting areas, for their prebasic molt in August-October. Long-distance dispersal (≥ 100 km) from Año Nuevo Bay by radiomarked Marbled Murrelets was low during breeding (9-13%, n = 46), but was greater for individuals radiomarked at the end of the breeding season (69-90%, n = 20). The mean dispersal dates were 18 May and 21 October for the breeding and postbreeding samples, respectively, and postbreeding dispersal occurred an average of two weeks after molt completion. Mean dispersal distances were 184 km and 256 km in the breeding and postbreeding periods, respectively. Of 12 long-distance dispersers, all moved south except one. Marbled Murrelets gained mass during molt (n = 184), except during a moderate El Niño event in 2002 when mass remained constant. However, birds did not take longer to molt in 2002, which suggests that individuals allocated more energy reserves to molt processes in that year. Apparently, sufficient prey resources were available in Año Nuevo Bay for both basic metabolic requirements and the demands of molt, even when water was moderately warm. © The American Ornithologists' Union, 2008., Cited By (since 1996):6, Marine Mammals, Birds & Turtles, CODEN: AUKJA, ,
Author: Peery, Henkel, Newman, Becker, Harvey, Thompson, Beissinger
Date: 2008-01-01T00:00:00Z

Title: Temporal variability in ocean climate and California sea lion diet and biomass consumption: Implications for fisheries management,
Description: Key to understanding ecosystem structure and function in the California Current System is quantitative modeling of trophic interactions of California sea lions Zalophus californianus, one of the largest and most abundant predators in this system, and how these interactions are affected by climate variability. Because sea lions consume almost exclusively commercially important prey species, we hypothesized that the potential for competition for specific prey resources would vary with environmental conditions. We evaluated seasonal and annual variation in sea lion diet in Monterey Bay during the strong 1997-98 El Niño and subsequent 1999 La Niña through the examination and identification of prey hard parts found in fecal samples. Annual consumption was modeled using population size, dietary data, sea lion energetics, and prey energy content. Sea lions were plastic specialists, feeding on seasonally abundant aggregating prey, exploiting several species at a time. Short-term seasonal changes in diet corresponded with prey movement and life history patterns, whereas long-term annual changes corresponded with large-scale ocean climate shifts, namely the large 1997-98 El Niño and 1999 La Niña. Annual sea lion consumption of specific prey varied as a function of ocean climate, with an estimated 17 154 t prey consumed in 1998 and 20 229 t in 1999. Sea lion consumption was similar in magnitude to fisheries landings for several prey species and has the potential to adversely impact specific prey resources and directly compete with these fisheries; however, the degree of competition depends on spatial and temporal overlap of fisheries and sea lion foraging efforts. © Inter-Research 2008., Cited By (since 1996):8, Marine Mammals, Birds & Turtles, CODEN: MESED, , , Downloaded from: http://www.int-res.com/abstracts/meps/v373/p157-172/ (16 June 2014).
Author: Weise, Harvey
Date: 2008-01-01T00:00:00Z

Title: An integrated approach for assessing translocation as an effective conservation tool for Hawaiian monk seals
Description: For threatened and endangered species, translocations have been widely used to mitigate multiple sources of mortality that threaten population recovery. Although numerous Hawaiian monk seals Neomonachus schauinslandi have been translocated for a variety of purposes, few monk seal translocations have addressed the problem of prey limitation. To assess the efficacy of using translocations to mitigate reduced prey availability, 12 weanling monk seals were translocated with pre-release health screening and post-release monitoring. Specifically, the health, foraging behavior, habitat use, and survival of translocated seals were compared with those of 17 monk seals resident to the release site. There was little evidence of infectious diseases in translocated and resident seals, although Chlamydophila abortus antibodies and enteric bacteria were detected in many individuals. Translocated and resident weanling seals also demonstrated similar diving, movements, and habitat use, whereas resident adult seals had greater variability in foraging patterns. First-year survival for translocated weanlings (50%, n = 12) and non-translocated weanlings at the donor (31%, n = 36) and recipient sites (69%, n = 16) was related to weaning body size, with larger individuals having greater survivorship. These results supported 3 main conclusions that have important consequences for future translocation and population recovery efforts: (1) there was minimal risk of exposing seals to novel infectious diseases as a result of translocation; (2) individuals translocated with limited foraging experience rapidly adapted to their post-release environment; and (3) translocation for the purpose of mitigating prey limitation is a viable and important conservation tool for Hawaiian monk seals. © Outside the USA the US Government 2017., Article
Author: Norris, Littnan, Gulland, Baker, Harvey

Title: Mortality of sea lions along the central California coast linked to a toxic diatom bloom,
Description: Over 400 California sea lions (Zalophus californianus) died and many others displayed signs of neurological dysfunction along the central California coast during May and June 1998. A bloom of Pseudo-nitzschia australis (diatom) was observed in the Monterey Bay region during the same period. This bloom was associated with production of domoic acid (DA), a neurotoxin that was also detected in planktivorous fish, including the northern anchovy (Engraulis mordax), and in sea lion body fluids. These and other concurrent observations demonstrate the trophic transfer of DA resulting in marine mammal mortality. In contrast to fish, blue mussels (Mytilus edulus) collected during the DA outbreak contained no DA or only trace amounts. Such findings reveal that monitoring of mussel toxicity alone does not necessarily provide adequate warning of DA entering the food web at levels sufficient to harmful marine wildlife and perhaps humans., Cited By (since 1996):331, CODEN: NATUA, ,
Author: Scholin, Gulland, Doucette, Benson, Busman, Chavez, Cordaro, DeLong, De Vogelaere, Harvey, Haulena, Lefebvre, Lipscomb, Loscutoff, Lowenstine, Marin III, Miller, McLellan, Moeller, Powell, Rowles, Silvagni, Silver, Spraker, Trainer, Van Dolah
Date: 2000-01-01T00:00:00Z

Title: Food habits, seasonal abundance, size, and sex of the blue shark, Prionace glauca, in Monterey Bay, California,
Description: , , ,
Author: Harvey
Date: 1989-01-01T00:00:00Z

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Managing our Digital Assets

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