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Catalina Island (catalina + island)
Kinds of Catalina Island Selected AbstractsPopulation genetic structure of the round stingray Urobatis halleri (Elasmobranchii: Rajiformes) in southern California and the Gulf of CaliforniaJOURNAL OF FISH BIOLOGY, Issue 2 2010S. M. Plank The round stingray, Urobatis halleri, is a viviparous elasmobranch that inhabits inshore, benthic habitats ranging from the western U.S.A. to Panama. The population genetic structure of this species was inferred with seven polymorphic microsatellite loci in samples collected at three sites in coastal southern California, one near Santa Catalina Island, California and one in the eastern Gulf of California. Urobatis halleri is relatively common, but little is known of its movement patterns or population structure. Small FST values (,0·0017 to 0·0005) suggested little structure among coastal populations of southern and Baja California. The population sampled at Santa Catalina Island, which is separated by a deep-water channel from the coastal sites, however, was significantly divergent (large FST, 0·0251) from the other populations, suggesting low connectivity with coastal populations. The Santa Catalina Island population also had the lowest allele richness and lowest average heterozygosity, suggesting recent population bottlenecks in size. [source] Reproductive behaviour of a temperate serranid fish, Paralabrax clathratus(Girard), from Santa Catalina Island, California, U.S.A.JOURNAL OF FISH BIOLOGY, Issue 1 2006B. E. Erisman The reproductive behaviour of the kelp bass Paralabrax clathratus was studied on Santa Catalina Island, California, U.S.A. from April 2000 to September 2002. Adults formed aggregations of three to > 200 individuals, and spawning occurred within subgroups of three to 23 individuals that contained a single female. The gonado-somatic index (IG) of collected ripe males (mean = 5·8%, range = 0·5,13·1%) indicated a large investment in sperm production that is common in group-spawning fishes characterized by intense sperm competition. Spawning occurred 32 min before sunset to 120 min after sunset, and both males and females were capable of spawning multiple times during a single evening. Behavioural observations of adults and estimates of spawning periodicity from the collection of females with hydrated oocytes suggested that spawning occurred continuously throughout the summer months and showed no significant relationship with the lunar cycle. In general, the spawning behaviour of kelp bass was similar to other functionally gonochoric, group-spawning serranids. The dynamics of P. clathratus spawning aggregations, however, were inconsistent with that of tropical reef fish spawning aggregations, including the transient spawning aggregations of some tropical serranids. Aggregation spawning appeared to be an important component of the annual reproduction of this species. [source] Phenotypic variation among populations of Atherinops affinis(Atherinopsidae) with insights from a geometric morphometric analysisJOURNAL OF FISH BIOLOGY, Issue 4 2004K. M. O'Reilly Morphological character variation was examined in Atherinops affinis, a temperate marine silverside with a broad geographic range and presumed limited powers of dispersal. Populations of this species were sampled from three California mainland sites, one Channel Island site and one site in the upper Gulf of California. A geometric morphometric analysis yielded higher resolution in the assessment of phenotypic divergence among the four Pacific coast populations than either body measurement or meristic analysis, and it showed that most of the shape variation among these populations occurs in the head region and body depth of the fish. All three analyses supported the hypothesis that populations of A. affinis from central and southern California coastal waters and from Santa Catalina Island are morphologically distinct from each other; the Santa Catalina Island population was found to be the most divergent. On the basis of meristic characters alone, the population of A. affinis from the upper Gulf of California was different from A. affinis populations along the Pacific coast of California. The analyses revealed variation in several morphological characters, e.g. body depth and meristics, known to vary in association with environmental conditions. Given that A. affinis appears to have low among-population genetic variation, this species may be phenotypically plastic in response to the environmental conditions of the habitat of each population. [source] Population structure of loggerhead shrikes in the California Channel IslandsMOLECULAR ECOLOGY, Issue 8 2004LORI S. EGGERT Abstract The loggerhead shrike (Lanius ludovicianus), a songbird that hunts like a small raptor, maintains breeding populations on seven of the eight California Channel Islands. One of the two subspecies, L. l. anthonyi, was described as having breeding populations on six of the islands while a second subspecies, L. l. mearnsi, was described as being endemic to San Clemente Island. Previous genetic studies have demonstrated that the San Clemente Island loggerhead shrike is well differentiated genetically from both L. l. anthonyi and mainland populations, despite the fact that birds from outside the population are regular visitors to the island. Those studies, however, did not include a comparison between San Clemente Island shrikes and the breeding population on Santa Catalina Island, the closest island to San Clemente. Here we use mitochondrial control region sequences and nuclear microsatellites to investigate the population structure of loggerhead shrikes in the Channel Islands. We confirm the genetic distinctiveness of the San Clemente Island loggerhead shrike and, using Bayesian clustering analysis, demonstrate the presence and infer the source of the nonbreeding visitors. Our results indicate that Channel Island loggerhead shrikes comprise three distinct genetic clusters that inhabit: (i) San Clemente Island, (ii) Santa Catalina Island and (iii) the Northern Channel Islands and nearby mainland; they do not support a recent suggestion that all Channel Island loggerhead shrikes should be managed as a single entity. [source] Possible contemporary evolution in an endangered species, the Santa Cruz Island foxANIMAL CONSERVATION, Issue 2 2009H. M. Swarts Abstract An ability to mount rapid evolutionary responses to environmental change may be necessary for species persistence in a human-dominated world. We present evidence of the possibility of such contemporary evolution in the anti-predator behaviour of the critically endangered Santa Cruz Island fox Urocyon littoralis. In 1994, golden eagles colonized Santa Cruz Island, CA and devastated the predator-naïve, endemic island fox population by 95% within 10 years. In 1992, just before the arrival of golden eagles, foxes showed substantial diurnal activity, but diurnal activity was 37.0% lower in 2003,2007, after golden eagle colonization; concurrently, overall activity declined and nocturnal activity increased. Moreover, on nearby Santa Catalina Island, where golden eagles were absent but where the fox population recently crashed due to a disease epidemic, remaining foxes were significantly more diurnally active than were those on Santa Cruz Island. The weight of evidence suggests that the change in activity pattern was a response to predation, not to low population density, and that this was probably a heritable rather than a learned behavioural trait. This behavioural change may allow for prolonged island fox persistence, but also potentially represents a loss of behavioural diversity in fox populations. [source] | ||||||||||