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1.
Summary Specimens ofPorichthys notatus, which are naturally luminous along the coast of California, are non-luminous in Puget Sound. However, luminescence capability may be induced in the adult Puget SoundPorichthys by the administration of purifiedCypridina (ostracod) luciferin, syntheticCypridina luciferin, orCypridina organisms. The bioluminescence emission spectra produced by the Puget Sound fish following induction is similar, if not identical, to that of the naturally luminousPorichthys notatus from California waters (maxima: 485 and 507 nm).  相似文献   

2.
ABSTRACT

Nuttall's white-crowned sparrow Zonotrichia leucophrys nuttalli and the Puget Sound white-crowned sparrow Z. i. pugetensis intergrade through a zone of hybridization in northern California. The songs of the two differ in the sequence of syllable types and in the phonology of the complex syllables. We did a playback experiment to males of both subspecies in the field and to females of both subspecies in the laboratory to determine their response to the two subspecies songs. By making alterations of features of the songs, we also attempted to identify characteristics that account for subspecific recognition. Males of both subspecies were more responsive to their own subspecies song than to that of the other subspecies. Substitution of Puget Sound complex syllables into the Nuttall's song caused a reduction in response by male Nuttall's, but alteration of a Nuttall's song to a Puget Sound sequence of syllables had no effect. Females of both subspecies gave more sexual displays when played a song of their own subspecies than when played that of the other subspecies. Female Nuttall's gave an intermediate response when played Nuttall's songs with Puget Sound complex syllables or when played Nuttall's songs altered to a Puget Sound sequence. Puget Sound females did not discriminate between their own subspecies song and either of the altered stimulus songs separately. They did respond less to a song that combined both alterations than to their own subspecies song.  相似文献   

3.
As part of the Puget Sound Ambient Monitoring Program of the Washington Department of Fish and Wildlife, serum samples from 380 harbor seals (Phoca vitulina) were tested for antibodies to Toxoplasma gondii in the modified agglutination test (MAT) incorporating formalin-fixed tachyzoites and mercaptoethanol. Antibodies to T. gondii were found in 29 of 380 (7.6%) seals with titers of 1:25 in 13, 1:50 in 14, and > or = 1:500 in 2 seals. Results indicate natural exposure of these wild marine mammals to T. gondii oocysts.  相似文献   

4.
Three enzyme systems, MDH, PGM and AGPDH, were investigated in starry flounder collected from off northwestern Hokkaido Island, Japan; western Kamchatka; USSR; Puget Sound, Washington, USA; and Yaquina Bay, Oregon, USA. Significant differences in MDH allele distribution were found between the Asian-Puget Sound and Yaquina Bay-Puget Sound samples suggesting that this system may be useful to separate different population units. The allele frequencies of MDH and PGM did not show significant variation with body length and handedness in starry flounder collected from Puget Sound, Washington, and did not support the hypothesis of differential viability between dextral and sinistrial forms of starry flounder.  相似文献   

5.
Synopsis The painted greenling, Oxylebius pictus, a hexagrammid fish of shallow, northeastern Pacific rocky habitats was observed and collected near the center of its range at Monterey Bay, California, and near the northern limit of its distribution at Puget Sound. Life history characteristics were compared for breeding stocks from the two areas. Mean and maximum adult body sizes (lengths and wet weights) and longevities of both sexes are greater at Puget Sound. Also, both males and females reach sexual maturity at a smaller body length at Monterey. Age group 0 and I juveniles are twice as abundant as adults at Monterey but rare at Puget Sound. Monterey females have greater relative fecundities. Egg development rates are similar at equivalent temperatures; eggs are smaller, however, at Monterey, and thus embryos are smaller at hatching. Length increase is faster for Puget Sound juveniles; adult fish in the two areas grow in length at comparable rates, although weight per body length is consistently greater for Monterey fish. These findings reflect a poorer survivorship at Monterey, where natural predation on fertilized eggs and the mortality rates of adult males are greater.  相似文献   

6.
Three enzyme systems, MDH, PGM and AGPDH, were investigated in starry flounder collected from off northwestern Hokkaido Island, Japan; western Kamchatka; USSR; Puget Sound, Washington, USA; and Yaquina Bay, Oregon, USA. Significant differences in MDH allele distribution were found between the Asian-Puget Sound and Yaquina Bay-Puget Sound samples suggesting that this system may be useful to separate different population units.
The allele frequencies of MDH and PGM did not show significant variation with body length and handedness in starry flounder collected from Puget Sound, Washington, and did not support the hypothesis of differential viability between dextral and sinistrial forms of starry flounder.  相似文献   

7.
Population genetic structure was determined for the planktonic diatom Ditylum brightwellii (West) Grunow in two connected estuaries—Puget Sound and the Strait of Juan de Fuca (WA, USA). Three genetically distinct populations were detected that were characterized by different microsatellite allele distributions and unique alleles. Isolates from the two most genetically diverged populations displayed identical full‐length 18S rDNA sequences suggesting that either a single or two recently diverged species were sampled. The extent of genetic differentiation between populations was not correlated with distance between water samples or time between sampling. Instead, distinct populations were associated with different estuaries. In Puget Sound waters, one population was detected three times over the course of 28 months. Cells from this population were likely maintained inside Puget Sound over long periods through water recirculation within the Sound. In Strait of Juan de Fuca waters, two additional populations were detected. Maximum growth rates of Puget Sound isolates were significantly different from Strait of Juan de Fuca isolates, indicating that populations were composed of cells with different physiological capabilities. The genetic and physiological differentiation observed between populations from intermixing estuaries suggested that genetic exchange between populations was restricted through differential selection. Despite the potential for widespread dispersal in planktonic organisms, it appears that populations with distinct genetic and physiological characteristics can be maintained over long time periods through a combination of hydrology and differential selection.  相似文献   

8.
Understanding patterns of connectivity among marine fish populations with demersal adults and pelagic larvae is critical for effective conservation of west coast rockfishes. The brown rockfish (Sebastes auriculatus) occurs in nearshore habitat and is common from northern Baja California, Mexico to northern California, rare off the outer coast of Oregon and Washington and again common in the inland waters of Puget Sound, Washington. Here we examine patterns of microsatellite DNA diversity from throughout the species’ range as an indirect measure of long-term trends in larval dispersal. Genetic divergence was large and highly significant over all populations (F ST=0.056, P<0.0001), and was significantly correlated with geographic distance when considering coastal populations. The best estimates of mean coastal dispersal distance were on the order of 10 km or less per generation. Diversity was relatively low in the Puget Sound, suggesting that Puget Sound rockfish populations experienced a post-glacial founder effect followed by genetic isolation and low effective population size. Puget Sound individuals appeared to have recent mixed ancestry as a result of introgression with S. maliger and S. caurinus. Genetic isolation of Puget Sound fish provides a basis for consideration as a Distinct Population Segment (DPS) under the provisions of the Endangered Species Act. We recommend that coastal brown rockfish fisheries be managed at regional rather than coast-wide scales, and that design of marine reserve networks considers the surprisingly low realized dispersal distance of some species with high dispersal potential.  相似文献   

9.
Several rockfish species (genus Sebastes) along the northeastern Pacific Ocean have rapidly declined in abundance owing in part to overfishing. A striking exception is the dwarf-like Puget Sound rockfish Sebastes emphaeus, whose densities have increased by several orders of magnitude over the last several decades. To describe their genetic structure, we sequenced 395 bp from the mitochondrial control region of 128 S. emphaeus adults from 5 locations spanning approximately 120 km of the Northwest Straits of Washington state. We detected no significant genetic differentiation among these populations and substantial genetic variation within populations, a pattern that may indicate high levels of ongoing gene flow. Preliminary data from 2 microsatellite loci are also consistent with panmixia. The mtDNA sequences also suggest that Puget Sound rockfish populations have expanded substantially since the retreat of Pleistocene glaciers made habitat in Puget Sound region available approximately 12,000 years ago.  相似文献   

10.

Background

Understanding movement patterns is fundamental to population and conservation biology. The way an animal moves through its environment influences the dynamics of local populations and will determine how susceptible it is to natural or anthropogenic perturbations. It is of particular interest to understand the patterns of movement for species which are susceptible to human activities (e.g. fishing), or that exert a large influence on community structure, such as sharks.

Methodology/Principal Findings

We monitored the patterns of movement of 34 sixgill sharks Hexanchus griseus using two large-scale acoustic arrays inside and outside Puget Sound, Washington, USA. Sixgill sharks were residents in Puget Sound for up to at least four years before making large movements out of the estuary. Within Puget Sound, sixgills inhabited sites for several weeks at a time and returned to the same sites annually. Across four years, sixgills had consistent seasonal movements in which they moved to the north from winter to spring and moved to the south from summer to fall. Just prior to leaving Puget Sound, sixgills altered their behavior and moved twice as fast among sites. Nineteen of the thirty-four sixgills were detected leaving Puget Sound for the outer coast. Three of these sharks returned to Puget Sound.

Conclusions/Significance

For most large marine predators, we have a limited understanding of how they move through their environment, and this clouds our ability to successfully manage their populations and their communities. With detailed movement information, such as that being uncovered with acoustic monitoring, we can begin to quantify the spatial and temporal impacts of large predators within the framework of their ecosystems.  相似文献   

11.
Genetic substructure among groups of Pacific harbor seals, Phoca vitulina richardsi , along the western coast of the United States was investigated using mitochondrial DNA sequences. Blood and tissue samples were removed from 86 seals inhabiting Puget Sound and the Pacific coasts of Washington, Oregon, and California. A 320 base-pair segment of the control region was amplified using the polymerase chain reaction and directly sequenced. These data indicated a high level of diversity. Thirty variable sites were found that define 47 mitochondrial haplotypes. Among groups of P. v. richardsi sampled, 5 haplotypes were shared, but most (42) were unique to a locality. Haplotypic frequency and an Analysis of Molecular Variance (A mova ) revealed significant differences ( P = 0.001) among regions. Phylogenetic analysis indicated Puget Sound seals possess unique divergent lineages not found in seals from the coasts of Washington, Oregon, and California. These lineages may represent haplotypes from north of Washington, which is consistent with late reproductive timing of harbor seals from Puget Sound.  相似文献   

12.
The non-native tunicates Didemnum vexillum, Ciona savignyi, and Styela clava are of concern to resource managers of Puget Sound, Washington, USA because they have been shown to threaten native species diversity and shellfish aquaculture in other regions. Invasive tunicates in Puget Sound occur mainly on man-made structures such as floating docks and aquaculture facilities. We conducted studies of the three species of concern and a fourth introduced tunicate, Botrylloides violaceus, that occur on these structures to evaluate their effects on mussels and native invertebrate communities. Because most studies of community effects of tunicates have dealt with sessile fouling organisms, we focused instead on epibenthic organisms such as meiofaunal harpacticoid copepods and macrofaunal polychaetes and amphipods that are known to be important prey for juvenile salmon and other small fish. Similar studies have shown mixed results, with negative, positive, or no effects depending on the species. We also found few community-level effects. Abundances of several species were lower when tunicates were present, but only at some of the sites. Several other species, including a non-native isopod, were significantly more abundant in the presence of tunicates. However, in most cases results were not statistically significant and more intensive, controlled sampling or experiments may be needed to demonstrate any consistent tunicate effects. Although invasive tunicates cause problems for mussel growers elsewhere, we did not find negative effects on mussels at four sites in Puget Sound. Given the large impacts known to accompany tunicate invasions elsewhere and their relatively recent invasions into Puget Sound, monitoring of their populations and effects should continue in the region.  相似文献   

13.
This study uses a mechanistic modeling approach to evaluate the effects of various climate pathways on the proliferative phase of the toxin-producing dinoflagellate Alexandrium in Puget Sound, WA, USA. Experimentally derived Alexandrium growth responses to temperature and salinity are combined with simulations of the regional climate and Salish Sea hydrology to investigate future changes in the timing, duration, and extent of blooms. Coarse-grid (100–200 km) global climate model ensemble simulations of the SRES A1B emissions scenario were regionally downscaled to a 12-km grid using the Weather Research and Forecasting model for the period 1969–2069. These results were used to: (1) analyze the future potential changes and variability of coastal upwelling winds, and (2) provide forcing fields to a Regional Ocean Model System used to simulate the circulation of the Salish Sea, including Puget Sound, and the coastal ocean. By comparing circa-1990 and circa-2050 climate scenarios for the environmental conditions that promote Alexandrium blooms, we disentangle the effects of three climate pathways: (1) increased local atmospheric heating, (2) changing riverflow magnitude and timing, and (3) changing ocean inputs associated with changes in upwelling-favorable winds. Future warmer sea surface temperatures in Puget Sound from increased local atmospheric heating increase the maximum growth rates that can be attained by Alexandrium during the bloom season as well as the number of days with conditions that are favorable for bloom development. This could lead to 30 more days a year with bloom-favorable conditions by 2050. In contrast, changes in surface salinity arising from changes in the timing of riverflow have a negligible effect on Alexandrium growth rates, and the behavior of the coastal inputs in the simulations suggests that changes in local upwelling will not have major effects on sea surface temperature or salinity or Alexandrium growth rates in Puget Sound.  相似文献   

14.
Bald eagles (Haliaeetus leucocephalus) are recovering from severe population declines, and are exerting pressure on food resources in some areas. Thousands of bald eagles overwinter near Puget Sound, primarily to feed on chum salmon (Oncorhynchus keta) carcasses. We used modeling techniques to examine how anticipated climate changes will affect energetic demands of overwintering bald eagles. We applied a regional downscaling method to two global climate change models to obtain hourly temperature, precipitation, wind, and longwave radiation estimates at the mouths of three Puget Sound tributaries (the Skagit, Hamma Hamma, and Nisqually rivers) in two decades, the 1970s and the 2050s. Climate data were used to drive bald eagle bioenergetics models from December to February for each river, year, and decade. Bald eagle bioenergetics were insensitive to climate change: despite warmer winters in the 2050s, particularly near the Nisqually River, bald eagle food requirements declined only slightly (<1%). However, the warming climate caused salmon carcasses to decompose more rapidly, resulting in 11% to 14% less annual carcass biomass available to eagles in the 2050s. That estimate is likely conservative, as it does not account for decreased availability of carcasses due to anticipated increases in winter stream flow. Future climate-driven declines in winter food availability, coupled with a growing bald eagle population, may force eagles to seek alternate prey in the Puget Sound area or in more remote ecosystems.  相似文献   

15.
Clostridium perfringens in the Environment   总被引:4,自引:2,他引:2       下载免费PDF全文
Clostridium perfringens was isolated from samples collected in Puget Sound in the state of Washington and areas considered as possible sources of these organisms to Puget Sound. The distribution of C. perfringens in the total Clostridium population was determined for fish gut contents and sediments collected in highly polluted and less polluted areas, sewage samples, freshwater sediments, and soils. The greatest numbers of C. perfringens were obtained from marine sediments collected near the sewage outfall at West Point. Fewer isolates were made from fish collected from less polluted stations, although the number of C. perfringens remained high in sediments from other Puget Sound stations. The proportion of C. perfringens in the total Clostridium populations varied between 56 and 71% for sewage samples and only 0.4 to 4.1% for freshwater sediments and soil samples. Only 25 C. perfringens isolates out of 137 from fish guts, or 18%, were identifiable serologically and these fell into 12 groups. C. perfringens were fed to fish and the fish were sacrificed after varying lengths of time. The number of C. perfringens increased slightly in the gut during the first 24 h and then the numbers decreased rapidly for the next 120 h.  相似文献   

16.
Human-health relevant impacts on marine ecosystems are increasing on both spatial and temporal scales. Traditional indicators for environmental health monitoring and microbial risk assessment have relied primarily on single species analyses and have provided only limited spatial and temporal information. More high-throughput, broad-scale approaches to evaluate these impacts are therefore needed to provide a platform for informing public health. This study uses shotgun metagenomics to survey the taxonomic composition and antibiotic resistance determinant content of surface water bacterial communities in the Puget Sound estuary. Metagenomic DNA was collected at six sites in Puget Sound in addition to one wastewater treatment plant (WWTP) that discharges into the Sound and pyrosequenced. A total of ∼550 Mbp (1.4 million reads) were obtained, 22 Mbp of which could be assembled into contigs. While the taxonomic and resistance determinant profiles across the open Sound samples were similar, unique signatures were identified when comparing these profiles across the open Sound, a nearshore marina and WWTP effluent. The open Sound was dominated by α-Proteobacteria (in particular Rhodobacterales sp.), γ-Proteobacteria and Bacteroidetes while the marina and effluent had increased abundances of Actinobacteria, β-Proteobacteria and Firmicutes. There was a significant increase in the antibiotic resistance gene signal from the open Sound to marina to WWTP effluent, suggestive of a potential link to human impacts. Mobile genetic elements associated with environmental and pathogenic bacteria were also differentially abundant across the samples. This study is the first comparative metagenomic survey of Puget Sound and provides baseline data for further assessments of community composition and antibiotic resistance determinants in the environment using next generation sequencing technologies. In addition, these genomic signals of potential human impact can be used to guide initial public health monitoring as well as more targeted and functionally-based investigations.  相似文献   

17.
Bull trout (Salvelinus confluentus) is a char listed as threatened under the United States Endangered Species Act throughout its range in the coterminous United States. Substantial morphological similarities between bull trout and Dolly Varden (S. malma) make field identification difficult. This has resulted in an incomplete understanding of their distribution and abundance in Washington State where these two species occur sympatrically. We used three diagnostic nuclear loci to determine the species of char collected at a trap on the White River in southern Puget Sound (Washington State, USA). Each of the 104 samples revealed the expected bull trout genotype at all three loci. This work presents three principle results: (i) the presence of a migratory bull trout population in southern Puget Sound; (ii) no evidence of migratory Dolly Varden over 3 years; and (iii) no evidence of hybridization was detected. These results also demonstrate how molecular markers can provide information essential to the conservation and management of these species.  相似文献   

18.
A.M. Cox  D.H. Shull  R.A. Horner   《Harmful algae》2008,7(4):379-388
The magnitude of paralytic shellfish poisoning (PSP) toxins in shellfish and the geographical scope of shellfish closures in Puget Sound have increased in recent decades. PSP, monitored by the Washington Department of Health, has spread from Sequim Bay in the 1950s into central Puget Sound in the 1970s and throughout Puget Sound by the 1990s. Alexandrium catenella, the species responsible for PSP toxins, produces a benthic resting cyst that, upon germinating, can seed blooms. This study examined whether there is a relationship between profiles of cysts in the sediment and temporal variation in PSP in shellfish and if the history of the toxin's southward expansion through Puget Sound can be seen in the cyst record. To address this question, sediment cores were collected from three Puget Sound basins, Sequim Bay, Penn Cove, and Carr Inlet, and cyst profiles were determined. Activities of 210Pb were fitted to a depth-dependent diagenetic model to date the sediment cores and determine mixing and sediment-accumulation rates. In order to compare historical variation in PSP with cyst profiles that have been altered by bioturbation, a depth and time-dependent diagenetic model was then used to predict vertical profiles of cysts that would occur under the assumption that cyst deposition rates are proportional to PSP concentration in shellfish measured over several decades at each site. The cyst profiles predicted by the model were compared to measured cyst profiles. These comparisons suggested that Alexandrium blooms and resulting PSP concentration in shellfish are more closely linked to cyst germination and deposition at some stations than at others. Sequim Bay had relatively large numbers of cysts and it is likely that the persistent toxicity here is the result of recurrent seeding from the cyst bed. Penn Cove and Carr Inlet had few cysts despite occasional blooms, suggesting that blooms are transported into those areas, perhaps from other sites of cyst germination. Sequim Bay and Penn Cove had cysts from top to bottom of the cores so it was not possible to determine the date when cysts were first introduced into these bays, but it is likely that A. catenella has been in Penn Cove since at least 1955 or for about two decades before the WDOH PSP toxicity data would indicate. The cyst profile in Carr Inlet suggested a first appearance date of 1985 that is consistent with the first appearance of PSP in shellfish in 1988.  相似文献   

19.
Phenanthrene- and naphthalene-degrading bacteria were isolated from four offshore and nearshore locations in the Gulf of Mexico by using a modified most-probable-number technique. The concentrations of these bacteria ranged from 102 to 106 cells per ml of wet surficial sediment in mildly contaminated and noncontaminated sediments. A total of 23 strains of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria were obtained. Based on partial 16S ribosomal DNA sequences and phenotypic characteristics, these 23 strains are members of the genus Cycloclasticus. Three representatives were chosen for a complete phylogenetic analysis, which confirmed the close relationship of these isolates to type strain Cycloclasticus pugetii PS-1, which was isolated from Puget Sound. PAH substrate utilization tests which included high-molecular-weight PAHs revealed that these isolates had similar, broad substrate ranges which included naphthalene, substituted naphthalenes, phenanthrene, biphenyl, anthracene, acenaphthene, and fluorene. Degradation of pyrene and fluoranthene occurred only when the strains were incubated with phenanthrene. Two distinct partial PAH dioxygenase iron sulfur protein (ISP) gene sequences were PCR amplified from Puget Sound and Gulf of Mexico Cycloclasticus strains. Phylogenetic analyses of these sequences revealed that one ISP type is related to the bph type of ISP sequences, while the other ISP type is related to the nah type of ISP sequences. The predicted ISP amino acid sequences for the Gulf of Mexico and Puget Sound strains are identical, which supports the hypothesis that these geographically separated isolates are closely related phylogentically. Cycloclasticus species appear to be numerically important and widespread PAH-degrading bacteria in both Puget Sound and the Gulf of Mexico.  相似文献   

20.
Azaspiracids (AZA) are novel lipophilic polyether marine biotoxins associated with azaspiracid shellfish poisoning (AZP). Azaspiracid-59 (AZA-59) is a new AZA that was recently detected in strains of Azadinium poporum from Puget Sound, Washington State. In order to understand how environmental factors affect AZA abundances in Puget Sound, a laboratory experiment was conducted with two local strains of A. poporum to estimate the growth rate and AZA-59 (both intra- and extracellular) cell quotas along temperature and salinity gradients. Both strains of A. poporum grew across a wide range of temperatures (6.7 °C to 25.0 °C), and salinities (15 to 35). Growth rates increased with increasing temperature up to 20.0 °C, with a range from 0.10 d−1 to 0.42 d−1. Both strains of A. poporum showed variable growth rates from 0.26 d−1 to 0.38 d−1 at salinities from 15 to 35. The percentage of intracellular AZA-59 in both strains was generally higher in exponential than in stationary phase along temperature and salinity gradients, indicating higher retention of toxin in actively growing cells. Cellular toxin quotas varied by strain in both the temperature and salinity treatments but were highest at the lowest growth rates, especially for the faster growing strain, NWFSC1011.Consistent with laboratory experiments, field investigations in Sequim Bay, WA, during 2016–2018 showed that A. poporum was detected when salinity and temperature became favorable to higher growth rates in June and July. Although current field data of A. poporum in Puget Sound indicate a generally low abundance, the potential of local A. poporum to adapt to and grow in a wide range of temperature and salinity may open future windows for blooms. Although increased temperatures, anticipated for the Puget Sound region over the next decades, will enhance the growth of A. poporum, these higher temperatures will not necessarily support higher toxin cell quotas. Additional sampling and assessment of the total toxicity of AZA-59 will provide the basis for a more accurate estimation of risk for azaspiracid poisoning in Puget Sound shellfish.  相似文献   

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