| effects of age, colony, and sex on mercury concentrations in california sea lions. | we measured total mercury (thg) concentrations in california sea lions (zalophus californianus) and examined how concentrations varied with age class, colony, and sex. because hg exposure is primarily via diet, we used nitrogen (δ (15)n) and carbon (δ (13)c) stable isotopes to determine if intraspecific differences in thg concentrations could be explained by feeding ecology. blood and hair were collected from 21 adult females and 57 juveniles from three colonies in central and southern californi ... | 2016 | 26259982 |
| common cancer in a wild animal: the california sea lion (zalophus californianus) as an emerging model for carcinogenesis. | naturally occurring cancers in non-laboratory species have great potential in helping to decipher the often complex causes of neoplasia. wild animal models could add substantially to our understanding of carcinogenesis, particularly of genetic and environmental interactions, but they are currently underutilized. studying neoplasia in wild animals is difficult and especially challenging in marine mammals owing to their inaccessibility, lack of exposure history, and ethical, logistical and legal l ... | 2015 | 26056370 |
| insights into the life history and ecology of a large shortfin mako shark isurus oxyrinchus captured in southern california. | in june 2013, a record-breaking female isurus oxyrinchus (total length 373 cm, mass 600 kg) was captured by rod and reel off huntington beach, california, where it was subsequently donated to research and provided a rare opportunity to collect the first data for a female i. oxyrinchus of this size. counts of vertebral band pairs estimate the shark to have been c. 22 years old, depending upon assumptions of band-pair deposition rates, and the distended uteri and spent ovaries indicated that this ... | 2015 | 25998058 |
| the oldest known fur seal. | the poorly known fossil record of fur seals and sea lions (otariidae) does not reflect their current diversity and widespread abundance. this limited fossil record contrasts with the more complete fossil records of other pinnipeds such as walruses (odobenidae). the oldest known otariids appear 5-6 ma after the earliest odobenids, and the remarkably derived craniodental morphology of otariids offers few clues to their early evolutionary history and phylogenetic affinities among pinnipeds. we repo ... | 2015 | 25672999 |
| fractured genetic connectivity threatens a southern california puma (puma concolor) population. | pumas (puma concolor; also known as mountain lions and cougars) in southern california live among a burgeoning human population of roughly 20 million people. yet little is known of the consequences of attendant habitat loss and fragmentation, and human-caused puma mortality to puma population viability and genetic diversity. we examined genetic status of pumas in coastal mountains within the peninsular ranges south of los angeles, in san diego, riverside, and orange counties. the santa ana mount ... | 2014 | 25295530 |
| relation of dental wear to the concentrations of essential minerals in teeth of the california sea lion zalophus californianus californianus. | tooth wear in marine mammals has been attributed to age, feeding habits, behavior, and contaminants. advanced tooth wear in some california sea lions, including some of very young age (<5 yr), in the gulf of california, suggests that there are variations in chemical composition of tooth parts, wherein the concentrations of certain trace minerals might be anomalous, making them more susceptible to erosion. the concentrations of the essential minerals ca, p, k, na, fe, mg, and zn in the dentition ... | 2007 | 17435255 |
| trihalomethanes in marine mammal aquaria: occurrences, sources, and health risks. | disinfecting water containing the high levels of dissolved organic carbon (doc) commonly generated during pinniped husbandry may cause the formation of carcinogenic disinfection byproducts (dbps). little information is available on dbp levels, sources, and health risks in marine mammal aquaria. using the commonly observed trihalomethanes (thms) as a dbp indicator, we monitored concentrations for seven months at the marine mammal center in sausalito, california, one of the largest pinniped rehabi ... | 2014 | 24805374 |
| total body oxygen stores and physiological diving capacity of california sea lions as a function of sex and age. | a defining physiological capability for air-breathing marine vertebrates is the amount of oxygen that can be stored in tissues and made available during dives. to evaluate the influence of oxygen storage capacity on aerobic diving capacity, we examined the extent to which blood and muscle oxygen stores varied as a function of age, body size and sex in the sexually dimorphic california sea lion, zalophus californianus. we measured total body oxygen stores, including hematocrit, hemoglobin, mchc, ... | 2007 | 17210964 |
| lung collapse in the diving sea lion: hold the nitrogen and save the oxygen. | lung collapse is considered the primary mechanism that limits nitrogen absorption and decreases the risk of decompression sickness in deep-diving marine mammals. continuous arterial partial pressure of oxygen profiles in a free-diving female california sea lion (zalophus californianus) revealed that (i) depth of lung collapse was near 225 m as evidenced by abrupt changes in during descent and ascent, (ii) depth of lung collapse was positively related to maximum dive depth, suggesting that the se ... | 2012 | 22993241 |
| undifferentiated high-grade pleomorphic sarcoma in a california sea lion (zalophus californianus). | a tumour located in the pectoral region and the left front flipper was observed in a 29-year-old female california sea lion (zalophus californianus) that died following signs of respiratory disease and inappetence. metastases were present in the lung and adrenal gland. the histological pattern of the tumour was variable. in some areas the tumour consisted of pleomorphic fibroblast-like cells arranged in a storiform pattern, while in other areas it comprised oval or polygonal cells with round to ... | 2011 | 20708196 |
| the effects of water temperature on the energetic costs of juvenile and adult california sea lions (zalophus californianus): the importance of skeletal muscle thermogenesis for thermal balance. | as highly mobile marine predators, many pinniped species routinely encounter a wide range of water temperatures during foraging and in association with seasonal, geographical and climatic changes. to determine how such variation in environmental temperature may impact energetic costs in otariids, we determined the thermal neutral zone of adult and juvenile california sea lions (zalophus californianus) by measuring resting metabolic rate using open-flow respirometry. five adult female (body mass ... | 2009 | 19946075 |
| weak polygyny in california sea lions and the potential for alternative mating tactics. | female aggregation and male territoriality are considered to be hallmarks of polygynous mating systems. the development of genetic parentage assignment has called into question the accuracy of behavioral traits in predicting true mating systems. in this study we use 14 microsatellite markers to explore the mating system of one of the most behaviorally polygynous species, the california sea lion (zalophus californianus). we sampled a total of 158 female-pup pairs and 99 territorial males across t ... | 2012 | 22432039 |
| risk factors associated with development of poxvirus lesions in hospitalized california sea lions. | to identify risk factors that may predispose california sea lions (zalophus californianus) to development of cutaneous poxvirus nodules during hospitalization in a rehabilitation center. | 2005 | 16121616 |
| ddt in california sea lions. | | 1971 | 4942890 |
| behavioral control of body temperature in the unrestrained california sea lion. | | 1971 | 5134250 |
| development of a fatted male phenomenon in california sea lions. | | 1971 | 5170706 |
| seasonal prevalence and intensity of hookworms (uncinaria spp.) in california sea lion (zalophus californianus) pups born in 2002 on san miguel island, california. | intestines of california sea lion (zalophus californianus) pups (n= 204), born in 2002 on san miguel island, california, were examined for hookworms (uncinaria spp.) as part of a seasonal mortality study from june through december 2002 and january 2003. the investigation was planned to coincide with most of the previously established hookworm infection period of the pups. prevalence of hookworms in dead pups was 100% for each month of the study. the geometric mean intensity of infections per mon ... | 2005 | 15824900 |
| the role of organochlorines in cancer-associated mortality in california sea lions (zalophus californianus). | wild california sea lions (zalophus californianus) have an unusually high prevalence of neoplasms (18% of stranded dead adults) and high levels of contaminants. the contribution of organochlorine (oc) tissue burdens to the probability of sea lions dying from carcinoma was explored using a logistic regression model. levels of pcbs and ddts were determined in blubber of sea lions diagnosed with metastatic carcinoma and animals that had died from non-carcinoma-related incidents (e.g., gunshot, domo ... | 2005 | 15664031 |
| chronic aortitis in the california sea-lion, zalophus californianus. | | 1960 | 14405285 |
| tumor morphology and immunohistochemical expression of estrogen receptor, progesterone receptor, p53, and ki67 in urogenital carcinomas of california sea lions (zalophus californianus). | metastatic carcinoma of urogenital origin is a common cause of mortality in free-ranging california sea lions (zalophus californianus). the etiology of this cancer is likely multifactorial, with viral infection, genetic factors, and exposure to environmental organochlorine contaminants possible contributing factors. in this study, expression of estrogen receptor alpha (er alpha), progesterone receptor (pr), p53, and ki67 were evaluated by immunohistochemistry in 12 sea lions with metastatic carc ... | 2009 | 19276047 |
| the role of domoic acid in abortion and premature parturition of california sea lions (zalophus californianus) on san miguel island, california. | domoic acid is a glutaminergic neurotoxin produced by marine algae such as pseudo-nitzschia australis. california sea lions (zalophus californianus) ingest the toxin when foraging on planktivorous fish. adult females comprise 60% of stranded animals admitted for rehabilitation due to acute domoic acid toxicosis and commonly suffer from reproductive failure, including abortions and premature live births. domoic acid has been shown to cross the placenta exposing the fetus to the toxin. to determin ... | 2009 | 19204339 |
| conserving connectivity: some lessons from mountain lions in southern california. | habitat corridors can be essential for persistence of wildlife populations in fragmented landscapes. although much research has focused on identifying species and places critical for conservation action, the conservation literature contains surprisingly few examples of corridors that actually have been protected and so provides little guidance for moving from planning through implementation. we examined a case study from southern california that combines monitoring of radio-collared mountain lio ... | 2009 | 18983604 |
| a behaviorally explicit demographic model integrating habitat selection and population dynamics in california sea lions. | although there has been a call for the integration of behavioral ecology and conservation biology, there are few tools currently available to achieve this integration. explicitly including information about behavioral strategies in population viability analyses may enhance the ability of conservation biologists to understand and estimate patterns of extinction risk. nevertheless, most behavioral-based pva approaches require detailed individual-based data that are rarely available for imperiled s ... | 2008 | 18680502 |
| inbreeding: disease susceptibility in california sea lions. | | 2003 | 12621424 |
| organochlorine pollutants [corrected] in california sea lions revisited. | dichlorodiphenyltrichloroethane (ddt) and polychlorinated biphenyls (pcbs) are ubiquitous environmental contaminants that have been banned in most countries, but considerable amounts continue to cycle the ecosphere. top trophic level predators, like sea birds and marine mammals, bioaccumulate these lipophilic compounds, reflecting their presence in the environment. | 2002 | 12479795 |
| novel symptomatology and changing epidemiology of domoic acid toxicosis in california sea lions (zalophus californianus): an increasing risk to marine mammal health. | harmful algal blooms are increasing worldwide, including those of pseudo-nitzschia spp. producing domoic acid off the california coast. this neurotoxin was first shown to cause mortality of marine mammals in 1998. a decade of monitoring california sea lion (zalophus californianus) health since then has indicated that changes in the symptomatology and epidemiology of domoic acid toxicosis in this species are associated with the increase in toxigenic blooms. two separate clinical syndromes now exi ... | 2008 | 18006409 |
| molecular characterization of expressed dqa and dqb genes in the california sea lion ( zalophus californianus). | to date, there are no published mhc sequences from the california sea lion (zalophus californianus), a thriving species that, by feeding high on the marine food web, could be a sentinel for disturbances in marine and coastal ecosystems. in this study, degenerate primers and race technology were used to amplify near-full-length (mhczaca- dqb) and full-length (mhczaca- dqa) expressed class ii mhc gene products from the peripheral blood mononuclear cells of two california sea lions in rehabilitatio ... | 2002 | 12185537 |
| domoic acid toxicity in californian sea lions (zalophus californianus): clinical signs, treatment and survival. | eighty-one californian sea lions (zalophus californianus) with signs of domoic acid toxicity stranded along the coast of california in 1998 when there were blooms of the domoic acid-producing alga pseudonitzschia australis off-shore. in 2000, a further 184 sea lions stranded with similar clinical signs, but the strandings occurred both during detectable algal blooms and after the blooms had subsided. the clinical signs in these 265 californian sea lions included seizures, ataxia, head weaving, d ... | 2002 | 11995679 |
| mortality of sea lions along the central california coast linked to a toxic diatom bloom. | 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 ... | 2000 | 10638756 |
| coccidioidomycosis in free-living california sea lions (zalophus californianus) in central california. | coccidioidomycosis is described in seven california sea lions (zalophus californianus) admitted to the marine mammal center, sausalito, california (usa), between january 1986 and december 1994. diagnoses were confirmed by histology in all seven cases, culture in three cases, and serology in one case. these are believed to be the first published cases of coccidioidomycosis in free-ranging california sea lions. | 1996 | 9359077 |
| metastatic carcinoma of probable transitional cell origin in 66 free-living california sea lions (zalophus californianus), 1979 to 1994. | sixty-six (18%) cases of widely metastatic carcinoma of probable transitional cell origin were identified in 370 california sea lions (zalophus californianus) stranded alive along the central california (usa) coast, between january 1979 and december 1994. live animals were usually emaciated and anorectic, with perineal edema and occasionally hind-flipper paralysis or paresis. large yellow caseous masses were observed in the sub-lumbar lymph nodes, often extending around the ureters resulting in ... | 1996 | 8722262 |
| hookworm enteritis with bacteremia in california sea lion pups on san miguel island. | large breeding populations of california sea lions (zalophus californianus) are located on san miguel and san nicolas islands in the southern california bight. in 2001, there was a substantial increase in pup mortality in late summer and fall. from june 2002 to january 2003, 208 freshly dead pups were examined on san miguel island, the most western of the channel islands off the coast of southern california. tissues from 186 of these pups were examined histologically. the primary lesions in 133 ... | 2007 | 17495302 |
| metallothionein and the subcellular localization of mercury and cadmium in the california sea lion. | | 1977 | 17507 |
| underwater localization of click and pulsed pure-tone signals by the california sea lion (zalophus californianus). | | 1975 | 1117093 |
| behavioral thermoregulation in the california sea lion. | | 1974 | 4815152 |
| clinical relevance of novel otarine herpesvirus-3 in california sea lions (zalophus californianus): lymphoma, esophageal ulcers, and strandings. | herpesviruses have been recognized in marine mammals, but their clinical relevance is not always easy to assess. a novel otarine herpesvirus-3 (othv3) was detected in a geriatric california sea lion (zalophus californianus), and using a newly developed quantitative pcr assay paired with histology, othv3 was associated with esophageal ulcers and b cell lymphoblastic lymphoma in this animal. the prevalence and quantities of othv3 were then determined among buffy coats from 87 stranded and managed ... | 2012 | 23234600 |
| tissue heavy metal concentrations of stranded california sea lions (zalophus californianus) in southern california. | concentrations of nine heavy metals (as, cd, cu, fe, hg, pb, mn, mo and zn) were determined in the hepatic and renal tissues of 80 stranded california sea lions (zalophus californianus). significant age-dependant increases were observed in liver and kidney concentrations of cadmium and mercury, and renal zinc concentrations. hepatic iron concentrations were significantly higher in females than males. animals with suspected domoic acid associated pathological findings had significantly higher con ... | 2007 | 17116350 |
| contrasting effects of heterozygosity on survival and hookworm resistance in california sea lion pups. | low genetic heterozygosity is associated with loss of fitness in many natural populations. however, it remains unclear whether the mechanism is related to general (i.e. inbreeding) or local effects, in particular from a subset of loci lying close to genes under balancing selection. here we analyse involving heterozygosity-fitness correlations on neonatal survival of california sea lions and on susceptibility to hookworm (uncinaria spp.) infection, the single most important cause of pup mortality ... | 2006 | 16689912 |
| mhc gene configuration variation in geographically disparate populations of california sea lions (zalophus californianus). | major histocompatibility complex (mhc) class ii drb genotypes were examined in two geographically isolated populations of california sea lions (zalophus californianus) (gulf of california and california coastal pacific ocean). genomic dna from 227 california sea lions was examined using eight sequence-specific primer (ssp) pairs flanking the putative peptide-binding site. a total of 40 different zaca-drb genotype configurations were identified among the 227 individuals. using ssp-pcr, significan ... | 2006 | 16448418 |
| parathion poisoning from flannelette sheets. | two small boys were admitted to the lions gate hospital in coma and acute respiratory distress. they improved and the first boy was sent home; after two nights he was back in hospital in a worsened state. poisoning with organic phosphate was suspected, and after investigation some flannelette sheets were taken from his home for testing. they proved to have been contaminated with parathion ("nerve gas") in the hold of a ship sailing from antwerp to vancouver; the parathion had been offloaded in c ... | 1965 | 14272498 |
| intestinal disaccharidases: absence in two species of sea lions. | pups of both the california and stellar sea lions have no intestinal enzymes for hydrolysis of sucrose, lactose, cellobiose, or trehalose. if these animals were given lactose or sucrose, they developed severe fermentative diarrhea and weight loss similar to the clinical syndrome encountered in infants with either hereditary or acquired intolerance to disaccharides. quired intolerance to disaccharides. | 1964 | 14149396 |
| leptospirosis in a california sea lion. | | 1972 | 4481104 |
| aerial and underwater visual acuity in the california sea lion (zalophus califernianus) as a function of luminance. | | 1971 | 5288866 |
| the distribution of 4-nonylphenol in marine organisms of north american pacific coast estuaries. | one of the chemical breakdown products of nonylphenol ethoxylates, 4-nonylphenol (4-np), accumulates in organisms and is of concern as an environmental pollutant due to its endocrine disrupting effects. we measured 4-np levels in the seawater, sediment, and twelve organisms within the california estuary, morro bay, and examined biomagnification of 4-np using stable isotope abundances (δ(15)n and δ(13)c) to quantify trophic position. 4-np concentrations in organisms from morro bay included 25000± ... | 2012 | 22257992 |
| heartworms in captive california sea lions. | | 1973 | 4795400 |
| premature births in california sea lions: association with high organochlorine pollutant residue levels. | premature pupping in california sea lions has been noted on the breeding islands since 1968. organochlorine pesticides and polychlorinated biphenyl residues were two to eight times higher in tissues of premature parturient females and pups than in similar tissues of full-term parturient females and pups collected on san miguel island in 1970. | 1973 | 4199282 |