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1.
Strategies to reduce, halt, and reverse global declines in marine biodiversity are needed urgently. We reviewed, coded, and synthesized historical and contemporary marine conservation strategies of the Kitasoo/Xai'xais First Nation in British Columbia, Canada to show how their approaches work. We assessed whether the conservation actions classification system by the Conservation Measures Partnership was able to encompass this nation's conservation approaches. All first-order conservation actions aligned with the Kitasoo/Xai'xais First Nation's historical and contemporary marine conservation actions; hereditary chief management responsibility played a key role. A conservation ethic permeates Kitasoo/Xai'xais culture, and indigenous resource management and conservation existed historically and remains strong despite extreme efforts by colonizers to suppress all indigenous practices. The Kitasoo/Xai'xais's embodiment of conservation actions as part of their worldview, rather than as requiring actions separate from everyday life (the norm in nonindigenous cultures), was missing from the conservation action classification system. The Kitasoo/Xai'xais are one of many indigenous peoples working to revitalize their governance and management authorities. With the Canadian government's declared willingness to work toward reconciliation, there is an opportunity to enable First Nations to lead on marine and other conservation efforts. Global conservation efforts would also benefit from enhanced support for indigenous conservation approaches, including expanding the conservation actions classification to encompass a new category of conservation or sacredness ethic.  相似文献   

2.
Like female dog whelks (Nucella lapillus) in the Atlantic Ocean, females of the Pacific gastropod N. lima respond to low concentrations of tri-n-butyltin (TBT) by growing a penis and vas deferens. This condition, termed imposex, was found to occur in N. lima collected from August 1987 to May 1988 along a TBT pollution gradient associated with a marina in Auke Bay, Alaska. The suite of symptoms characteristic of imposex in N. lima was slightly different than in N. lapillus. Imposex, as measured by relative penis size (RPS) of females to males, increased from 0.0 to 34.27 along this gradient and as measured by vas deferens sequenceindex (VDS) increased similarly from 0.0 to 4.29. Concentrations of TBT in N. lima increased from below detection limits (about 0.010 g Sn g-1 dry tissue wt) to 0.065 g Sn g-1 dry tissue wt along the gradient. The gradient was determined by measuring TBT in whole-body tissues of bay mussels (Mytilus edulis). Concentrations of TBT in mussels increased from below detection limits to 0.833 g Sn g-1 dry tissue wt in mussels from within the marina that was the major local source of TBT. Imposex, tissue TBT burden, and position along a TBT pollution gradient are significantly correlated (P<0.01) in N. lima. TBT was tested as a causative agent for imposex by exposing snails at a distant control site to TBT paint. After 1 mo exposure, 33% of the females grew a penis ranging in size from 0.2 to 0.8 mm. Our results generally corroborate those found for N. lapillus and indicate that imposex in N. lima is caused by environmental TBT exposure. We suggest that the RPS in the genus Nucella may be useful in monitoring TBT in coastal waters worldwide.  相似文献   

3.
4.
Summary Pure tonal whistle vocalizations from five species of dolphins found in the western North Atlantic had consistent, species-specific characteristics. The degree of differences between species, as based on the results of multivariate discriminant analysis (Fig. 2), correlated with the taxonomic and zoogeographic relations of the five dolphin species. Congeneric species had more similar vocalizations than species of different genera. Differences between sympatric species were greater than differences between allopatric species. Of the six whistle parameters measured, maximum frequency had the lowest coefficient of variation for all five species, and duration and number of inflection points had the highest coefficients of variation for all five species.  相似文献   

5.
Nitrogen fixation in the North Pacific Ocean   总被引:1,自引:0,他引:1  
Nitrogen fixation in the euphotic zone of the ocean was measured by C2H2 reduction and 15N2 incorporation associated with Trichodesmium sp. and also with Richelia intracellularis occurring within the cells of Rhizosolenia styliformis var. longispina, and R. cylindrus. The vertical distribution of N2 fixation activity, N2-fixing species, particulate matter and dissolved nutrients was measured. The effects of light intensity, sample concentration, length of incubation, and nutrient enrichment on the rates of C2H2 reduction were determined. Estimates of the importance of N2 fixation in adding previously uncycled nitrogen to the euphotic zone are given.  相似文献   

6.
The report includes quantitative and qualitative data on the phytoplankton from the First Canadian Transpacific Oceanographic Cruise from March to May 1969. Nanoplanktonic species (<20 m) were numerically dominant and, together with nertic diatoms, made up the larger portion of the biomass at all stations outside the Western Subarctic and Alaskan Gyres, where Denticulopsis seminae predominated. The nanoplankton consisted mainly of haptophycean, dinophycean and cryptophycean flagellates. Tropical oceanic dinoflagellates and diatoms were abundant in the net samples from Station 17 in the warm Kuroshio current but absent from Stations 24–27 in the Western Subarctic Gyre, Stations 2, 37–39 in the Alaskan Gyre, in which cold water oceanic species predominated, and Stations 31 and 33, south of the Aleutians. Subsurface maxima were common on the outward bound (westerly) leg in March.  相似文献   

7.
Mercury (Hg) is a ubiquitous environmental toxin that produces a wide range of adverse health effects in humans. Bioaccumulation of mercury in the aquatic food chain is a public concern for many countries. The aim of this study was to review the prevalence of Hg contamination in marine fauna in Thailand.  相似文献   

8.
The Tanat Valley area of North Powys, Wales, has a long history of metalliferous mining, the most active period of extraction being during the 18th century, while the largest mine, Llangynog, was in production until 1899. Ore minerals found in the area include galena (PbS), sphalerite (ZnS) and chalcopyrite (CuFeS2). Below the Llangynog mine the valley is heavily contaminated with elevated levels of Pb, Zn, Cu and Cd in soils and river sediments. On the valley floor subsoil metal levels frequently greatly exceed those of topsoils which probably reflects contamination of the floodplain during the peak period of mining. High levels of base metals in the stream sediments some 2 km downstream of the mine area are thought to be due to river erosion of the contaminated bank material. Contamination derived from the old mine tips results in extremely high levels of heavy metals in soils and stream sediments in the immediate vicinty of the old workings. Some metal contamination is also thought to derive from previously undetected mineralisation.  相似文献   

9.
Sand lance, Ammodytes hexapterus Pallas, forage for zooplankton in the water column and are under heavy predation from fish, marine birds and marine mammals. To avoid predation, these fish bury themselves in soft bottom sediments when not foraging and during overwintering. We collected sand lance in Sequim Bay, Washington State, USA, in 1982. In three experiments we presented the fish with: (1) four different sediment types (fine sand, coarse sand, gravel, silt) to determine their sediment preferences; (2) clean and oil-contaminated preferred sediment to determine whether the fish would avoid the contamination; and (3) clean unpreferred and oil-contaminated preferred sediment to determine whether the contamination would alter their sediment preferences. In the first experiment, sand lance preferred to bury in fine and coarse sands and avoided gravel and silt. In the second experiment, sand lance avoided sand contaminated with Prudhoe Bay crude oil (116 and 1050 ppm). In the third experiment, sand lance avoided the oiled sand (131 and 1041 ppm) and buried in clean gravel, and also avoided both oiled sand (113 and 1004 ppm) and clean silt, and chose to remain in the water column. The sediment particle size and the way it affects water flow through the sediment seemed to be responsible for the preferences. We suggest that the sediment type, the sediment distribution, the nutritional state of the fish, and the predation pressure influence how sand lance use the sediment as a refuge and how they respond to contamination of that refuge.Contribution No. 1392 of the School of Oceanography, University of Washington  相似文献   

10.
A monitoring programme was performed to use marine sediments as an indicator of marine contamination in Hong Kong. A total of 51 samples were collected from eight marine sites and analysed for pH, redox potential, salinity, total‐N, total‐P, total organic carbon, and total Cu, Zn Pb, Cr and Cd. Sites with high industrial or aquacultural activities contained high total organic carbon contents, total‐N and total‐P contents. Sediments from sites with high industrial activities also enriched with heavy metals. Metal speciation results indicate that Cu and Cr existed mainly in the organic fraction, Pb and Zn were distributed approximately equally in both the organic and residual fractions while Cd mainly occurred in the residual fraction. The Cu, Cr and Zn contents were highly correlated with total organic carbon contents. All samples were classified as non‐acid forming according to the net acid generation test and only samples from the industrial site released a high concentration of heavy metals under a complete oxidising condition. The present study reveals that organic and heavy metal pollution is serious in the marine sediments of Hong Kong, and industrial and aquacultural activities are probably the major sources of contamination.  相似文献   

11.
Most recent authors have called the bay mussels of the Pacific coast of North AmericaMytilus edulis Linnaeus, 1758. Thirteen samples ofedulis-like mussels were collected from California, Oregon, and Alaska, USA, in 1985, 1986 and 1987. Electrophoretic evidence from wight loci indicates that these samples consist of two genetically distinct groups, neither of which is similar toM. edulis from the Atlantic Ocean. Mussels in southern California are very similar toM. galloprovincialis Lamarck, 1819 from the Mediterranean Sea; it is probable thatM. galloprovincialis was introduced accidentally to southern California. Mussels in Oregon and Alaska are similar to those from the Baltic Sea and parts of eastern Canada; the nameM. trossulus Gould, 1850 has priority for this taxon. In central and nothern California,M. galloprovincialis, M. trossulus and their hybrids co-occur. Despite the presence of hybrids betweenM. galloprovincialis andM. trossulus, the genetic integrity which they maintain across large areas of the world warrants their recognition as two distinct species.  相似文献   

12.
Latitudinal differences in host-specificity of marine Monogenea and digenea   总被引:1,自引:0,他引:1  
Rohde  K. 《Marine Biology》1978,47(2):125-134
Data from 15 surveys of marine trematodes (average of 91 trematode species and more than 80 fish species per survey) and from 12 surveys of marine Monogenea (average of 52 Monogenea species and more than 49 fish species per survey) show that the degree of host specificity of marine digenetic trematodes increases from cold to warm seas; Monogenea do not show such a trend, and the trend is probably reversed in the Pacific Ocean. The difference between the two groups is explained in terms of r - and k - strategy. Monogenea tend to follow a k - strategy (great complexity of adult, few offspring), which results in a high degree of host- and sitespecificity to facilitate mating in low-density populations. Only one or a few related host species can be infected, and as more related host species are present in the warm Pacific, host-specificity there is reduced. Digenea tend to follow an r- strategy (simple strucure of adult, many offspring), part of which is to infect many ecologically suitable hosts. Host-specificity in cold-temperate seas is reduced because of the less patchy and ecologically less restricted distribution of hosts.  相似文献   

13.
Specimens of the abyssal grenadier Coryphaenoides armatus (Hector, 1875), from the western North Atlantic and eastern North Pacific Oceans were compared electrophoretically at 27 presumptive gene loci. At 6 of the 7 polymorphic loci there were only minor differences in allelic frequencies but a nearly fixed difference was found at one locus, phosphogluconate dehydrogenase. Eastern North Pacific grenadiers typically have a narrower interorbital space, a shorter dorsal interspace, more soft rays in the 1st dorsal fin (9–10 versus 8–9) and more pelvic fin rays (21–23 versus 18–21) than grenadiers from the western North Atlantic (as well as grenadiers from the eastern South Pacific, which were included in the biometric analysis). There is an apparent disjunction in the distribution of C. armatus in the eastern Pacific at the Gulf of Panamá which coincides with the change of morphology. It is suggested that North Pacific grenadiers comprise a subspecies, C. armatus variabilis Günther, 1878, which is morphologically distinct from the subspecies C. armatus armatus (Hector, 1875) of the other areas.  相似文献   

14.
V. J. Loeb 《Marine Biology》1980,60(2-3):189-200
The larval fish assemblage in the epipelagic zone of the North Pacific central gyre near Lat. 28°N, Long. 155°W during late summer was sampled with stratified opening/closing bongo nets. This assemblage exhibited recurring patterns of spatial and species distributions. Spatial patterns included species vertical distributions, co-occurrence and pathchiness; species patterns included species composition and abundance relations. Both types of patterns changed with depth, the most dramatic change occurring in relation to the bottom of the summer mixed layer. An examination of the physical and biological environments of the epipelagic zone with relation to the summertime species and spatial patterns and to seasonal changes in larval fish species structure indicates that the thermal structure of the upper water column may exert a major influence on overall ichtyoplanton species and spatial structures within the gyre.  相似文献   

15.
Six species of marine phytoplankton of different sizes and taxonomic categories were grown in microcosms under identical experimental conditions; the species cultured were: Pavlova lutheri (Prymnesiophyceae), Dunaliella tertiolecta (Chlorophyceae), Phaeodactylum tricornutum (Baciollariophyceae), Eutreptiella sp. (Euglenophyceae), Alexandrium tamarense (Dinophyceae), and Phaeocystis pouchetii (Prymnesiophyceae). The photosynthetic carbon metabolism of these phytoplankton was studied throughout the exponential and lag phases of growth after nutrient depletion. The relative incorporation of carbon into protein was positively correlated with phytoplankton growth, while carbon assimilation into low molecular weight metabolites (LMWM) and storage products, i.e., lipid and polysaccharides, generally increased under nutrient-limiting conditions. Clear taxonspecific differences were observed in the proportions of carbon incorporated into cell constituents. A significant linear relationship was consistently found between the relative synthesis of protein to LMWM, and both the production normalised to chlorophyll (P:B) and the phytoplankton growth rate. However, ANCOVA revealed significant, interspecific differences in these relationships.  相似文献   

16.
Phylogenetic relationships among vestimentiferans in the family Lamellibrachiidae collected from ten sites in the western Pacific were analyzed on the basis of the nucleotide sequence of part of a mitochondrial gene for cytochrome oxidase I. The 103 individuals analyzed were tentatively classified into five species: namely, Lamellibrachia satsuma, three tentative species inhabiting Japanese waters and one tentative species from the Manus Basin. Phylogenetic analysis of the four tentative species, L. satsuma, and two lamellibrachiids, whose sequences had been reported previously, namely L. columna from the Lau Basin and L. barhami from the Oregon Margin and the Middle Valley, revealed that the lamellibrachiids from Japanese waters were not monophyletic. While two tentative species from Japanese waters and L. columna formed a monophyletic group, the other tentative species from Japanese waters was closely related to the tentative species from the Manus Basin. L. satsuma was shown to be phylogenetically distinct from other lamellibrachiids of the western Pacific. A lamellibrachiid that had been collected from the Nikko Seamount was also demonstrated to be L. sastuma.  相似文献   

17.
Callus formation in seven species of agarophyte marine algae   总被引:5,自引:0,他引:5  
Callus formation of seven species of the agarophyte marine algae Phyllophora nervosa, Gracilaria verrucosa, Furcellaria fastigiata, ceramium kondoi, Gelidium vagum, Laurencia paniculata, Rhodymenia pertusa was obtained from 1984 to 1986. A new sterile agent, chlorhexidin bigluconate, was used to get axenic explants from the algae thalli. The formation of callus from axenic explants depended on temperature of cultivation. In the case of F. fastigiata and G. vagum it occurred at 12° to 20°C, and with P. nervosa at 18° to 26°C. The exchange of sucrose with mannitol in the culture medium and the addition of some growth regulators stimulated the formation of callus. Mass formation of lumpy and warty extensions was observed in the explants from leaf blades of P. nervosa. The results might be useful for improving the aquaculture of agarophyte marine algae.  相似文献   

18.
Simulation modeling was used to reconstruct Black-browed Albatross (Diomedea melanophris) population trends. Close approximations to observed data were accomplished by annually varying survival rates, reproductive success, and probabilities of returning to breed given success in previous years. The temporal shift in annual values coincided with the start of longline fishing at South Georgia and potential changes in krill abundance. We used 23 years of demographic data from long-term studies of a breeding colony of this species at Bird Island, South Georgia, to validate our model. When we used annual parameter estimates for survival, reproductive success, and probabilities of returning to breed given success in previous years, our model trajectory closely followed the observed changes in breeding population size over time. Population growth rate was below replacement (lambda < 1) in most years and was most sensitive to changes in adult survival. This supports the recent IUCN uplisting of this species from "Vulnerable" to "Endangered." Comparison of pre-1988 and post-1988 demography (before and after the inception of a longline fishery in the breeding area) reveals a decrease in lambda from 0.963 to 0.910. A life table response experiment (LTRE) showed that this decline in lambda was caused mostly by declines in survival of adults. If 1988-1998 demographic rates are maintained, the model predicts a 98% chance of a population of fewer than 25 pairs within 78 years. For this population to recover to a status under which it could be "delisted," a 10% increase in survival of all age classes would be needed.  相似文献   

19.
E. Sahlsten 《Marine Biology》1987,96(3):433-439
The uptake rates of the three nitrogen compounds ammonium, nitrate, and urea were measured in the oligotrophic North Central Pacific Gyre in August–September 1985. The measurements were performed by using 15N-labelled substrates and incubating for short-time periods (3 to 4 h) under simulated in situ conditions. Ambient concentrations of the nitrogenous nutrients were generally below 0.10 mol l-1. The average total daily nitrogen uptake rate, integrated over the euphotic zone, was 12.5 mmol N m-2 d-1. Diel studies in the upper water mass resulted in a calculated phytoplankton growth rate of 1.3 d-1. Ammonium was the dominating nutrient, accounting for on the average 54% of the total nitrogen uptake, while urea uptake represented 32% and nitrate 14%. Ammonium uptake rates at a coastal station off the Hawaiian Islands were very close to the rates found at the oceanic station. Organisms <3 m dominated the nitrogen assimilation, being responsible for about 75% of the ammonium uptake. The nitrogen uptake rates in this study seem to be higher than those found by earlier investigations in the area, but correlated well with other productivity measurements performed during the same cruise.  相似文献   

20.
V. J. Loeb 《Marine Biology》1979,53(2):173-191
Patterns of species structure are described for the larval fish assemblage in the North Pacific Central Gyre. About 30,000 larvae, primarily of mesopelagic fish species, were identified for 7 cruises. Samples were collected using Isaacs-Kidd plankton trawls on 6 cruises over a 4 1/2 year period; stratified samples were taken with an opening/closing bongo net on one late-summer cruise. Data on absolute and relative abundances, size ranges and summertime depth distributions of over 150 species of larvae are presented. The depth distribution and abundance of the ichthyoplankton are compared to those of the total zooplankton community. The larval assemblage is also examined with respect to the known adult mesopelagic fish assemblage. Seasonal changes in ichthyoplankton species structure occur but, within seasons, species structure is remarkably constant from year to year. Despite seasonal changes in species abundance and rank order of abundance, a constant cumulative frequency structure was found to exist in the ichthyoplankton, both between seasons and between years. The implications of this result are discussed in light of similar findings in a terrestrial community and with respect to possible mechanisms of regulation.  相似文献   

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