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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: 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: 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: Contaminant loads and hematological correlates in the harbor seal (Phoca vitulina) of San Francisco Bay, California,
Description: An expanding body of research indicates that exposure to contaminants may impact marine mammal health, thus possibly contributing to population declines. The harbor seal population of the San Francisco Bay (SFB), California, has suffered habitat loss and degradation, including decades of environmental contamination. To explore the possibility of contaminant-induced health alterations in this population, blood levels of polychlorinated biphenyls (PCBs), dichlorodiphenyldichloroethylene (DDE), and polybrominated diphenyl ethers (PBDEs) were quantified in free-ranging seals; relationships between contaminant exposure and several key hematological parameters were examined; and PCB levels in the present study were compared with levels determined in SFB seals a decade earlier. PCB residues in harbor seal blood decreased during the past decade, but remained at levels great enough that adverse reproductive and immunological effects might be expected. Main results included a positive association between leukocyte counts and PBDEs, PCBs, and DDE in seals, and an inverse relationship between red blood cell count and PBDEs. Although not necessarily pathologic, these responses may serve as sentinel indications of contaminant-induced alterations in harbor seals of SFB, which, in individuals with relatively high contaminant burdens, might include increased rates of infection and anemia. Copyright© Taylor & Francis Inc., Cited By (since 1996):22 Marine Mammals, Birds & Turtles, CODEN: JTEHD, ,
Author: Neale, Gulland, Schmelzer, Harvey, Berg, Allen, Greig, Grigg, Tjeerdema
Date: 2005-01-01T00:00:00Z

Title: Dynamics of vibrio with virulence genes detected in Pacific harbor seals (Phoca vitulina richardii) off California: Implications for marine mammal health
Description: Given their coastal site fidelity and opportunistic foraging behavior, harbor seals (Phoca vitulina) may serve as sentinels for coastal ecosystem health. Seals using urbanized coastal habitat can acquire enteric bacteria, including Vibrio that may affect their health. To understand Vibrio dynamics in seals, demographic and environmental factors were tested for predicting potentially virulent Vibrio in free-ranging and stranded Pacific harbor seals (Phoca vitulina richardii) off California. Vibrio prevalence did not vary with season and was greater in free-ranging seals (29 %, n = 319) compared with stranded seals (17 %, n = 189). Of the factors tested, location, turbidity, and/or salinity best predicted Vibrio prevalence in free-ranging seals. The relationship of environmental factors with Vibrio prevalence differed by location and may be related to oceanographic or terrestrial contributions to water quality. Vibrio parahaemolyticus, Vibrio alginolyticus, and Vibrio cholerae were observed in seals, with V. cholerae found almost exclusively in stranded pups and yearlings. Additionally, virulence genes (trh and tdh) were detected in V. parahaemolyticus isolates. Vibrio cholerae isolates lacked targeted virulence genes, but were hemolytic. Three out of four stranded pups with V. parahaemolyticus (trh+ and/or tdh+) died in rehabilitation, but the role of Vibrio in causing mortality is unclear, and Vibrio expression of virulence genes should be investigated. Considering that humans share the environment and food resources with seals, potentially virulent Vibrio observed in seals also may be of concern to human health. © 2013 Springer Science+Business Media New York., Marine Mammals, Birds & Turtles Harbor Seals, CODEN: MCBEB
Author: Hughes, Greig, Miller, Byrne, Gulland, Harvey
Date: 2013-01-01T00:00:00Z

Title: Domoic acid exposure and associated clinical signs and histopathology in Pacific harbor seals (Phoca vitulina richardii),
Description: Domoic acid (DA) is a potent neurotoxin that has caused strandings and mortality of seabirds and marine mammals off the California coast. Pacific harbor seals (Phoca vitulina richardii) are an abundant, nearshore species in California; however, DA exposure and toxicosis have not been documented for harbor seals in this region. To investigate DA exposure in harbor seals, samples were collected from free-ranging and stranded seals off California to assess exposure, clinical signs of toxicosis, and brain lesions in harbor seals exposed to DA. Domoic acid was detected in 65% (17/26) of urine samples collected from apparently healthy free-ranging seals, with concentrations of 0.4-11.7. ng/ml. Domoic acid also was detected in feces (2.4-2887. ng/g), stomach contents (1.4. ng/g; stranded only), milk (2.2. ng/ml; stranded only), amniotic fluid (9.7. ng/ml; free-ranging only), fetal meconium (14.6-39.8. ng/g), and fetal urine (2.0-10.2. ng/ml). Clinical signs indicative of DA toxicosis were observed in two live-stranded seals, and included disorientation, seizures, and uncoordinated movements. Histopathology revealed the presence of brain lesions consistent with DA toxicosis in two live-stranded seals, and one free-ranging seal that died during capture. Results indicated that harbor seals were exposed to DA, exhibited clinical signs and histological lesions associated with DA exposure, and that pups were exposed to DA in utero and during lactation via milk. Future investigation is required to determine the magnitude of impact that DA has on the health and mortality of harbor seals. © 2013 Elsevier B.V., Marine Mammals, Birds & Turtles, CODEN: HAALD, ,
Author: McHuron, Greig, Colegrove, Fleetwood, Spraker, Gulland, Harvey, Lefebvre, Frame
Date: 2013-01-01T00:00:00Z

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