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11.
Stakeholders are increasingly involved in species conservation. We sought to understand what features of a participatory conservation program are associated with its ecological and social outcomes. We conducted a case study of the management of invasive vertebrates in Australia. Invasive vertebrates are a substantial threat to Australia's native species, and stakeholder participation in their management is often necessary for their control. First, we identified potential influences on the ecological and social outcomes of species conservation programs from the literature. We used this information to devise an interview questionnaire, which we administered to managers of 34 participatory invasive-vertebrate programs. Effects of invasive species were related to program initiator (agency or citizen), reasons for use of a participatory approach, and stakeholder composition. Program initiator was also related to the participation methods used, level of governance (i.e., governed by an agency or citizens), changes in stakeholder interactions, and changes in abundance of invasive species. Ecological and social outcomes were related to changes in abundance of invasive species and stakeholder satisfaction. We identified relations between changes in the number of participants, stakeholder satisfaction, and occurrence of conflict. Potential ways to achieve ecological and social goals include provision of governmental support (e.g., funding) to stakeholders and minimization of gaps in representation of stakeholder groups or individuals to, for example, increase conflict mitigation. Our findings provide guidance for increasing the probability of achieving ecological and social objectives in management of invasive vertebrates and may be applicable to other participatory conservation programs.  相似文献   
12.
 Behavioral experiments have shown that male copepods of the species Tigriopus japonicus (Nori) can distinguish species, sex, and developmental stage of potential mates using contact chemoreception. Lectin-binding patterns on the body surface of females have indicated that surface-bound glycoproteins may be important signals in mate choice. In the present study, the proteolytic enzyme trypsin was used to cleave surface proteins from females, reducing their attractiveness to males. The protein fragments released were used to make monoclonal antibodies. Three levels of screening were used to identify monoclonal antibodies that recognized proteins involved in mate recognition. One monoclonal antibody bound to the terminal urosome and lateral prosome of CV females, and its binding significantly decreased female attractiveness to males. Western blotting showed that this antibody bound the trypsin-cleaved fragment and proteins of homogenized CV females and virgin adult females, but did not bind proteins of homogenized males, CIII females, or females of T. californicus or T. fulvus. This antibody recognized proteins on the surface of females that may enable males to discriminate conspecifics, sex, and age. It is likely that this molecule has a central role in the evolution of reproductive isolation in this group. Received: 22 July 1999 / Accepted: 21 March 2000  相似文献   
13.
Identification of a sex pheromone from a rotifer   总被引:7,自引:0,他引:7  
The first isolation and characterization of a sex pheromone from a zooplankter is reported. A 29 kdalton glycoprotein on the surface of females of the marine rotifer Brachionus plicatilis acts as a contact-mating pheromone. This glycoprotein (gp29) is glycosylated with oligosaccharides containing Nacetylglucosamine, mannose, and fucose residues, and these oligosaccharides are necessary for male recognition of females. Males detect this signal by contact chemoreception with receptors located in their corona. Binding of purified glycoprotein to male receptors reduces mating attempts by 93%. An antibody to the glycoprotein binds to females, reducing male mating attempts by 86%. When purified gp29 is bound to sepharose beads, it is sufficient to elicit male mating behavior. This glycoprotein is likely to play a key role in the evolution and maintenance of reproductive isolation in rotifers.  相似文献   
14.
Male copepods in the genus Tigriopus use surface proteins of female copepods to recognize appropriate mates. In a previous study of pre-copulatory mate-guarding in T. japonicus Mori, a monoclonal antibody was developed against one protein that contributed to the attractiveness of female T. japonicus as mate-guarding partners. In the present study, which was performed between December 1998 and November 2000, the antibody was used to purify two proteins from homogenates of pooled T. japonicus. A 70 kD protein was partially sequenced using mass spectrometry, revealing sequence similarity to α2-macroglobulin. It was shown that the 70 kD protein was highly expressed in stage CV females, the most attractive stage for mate-guarding. A purified 36 kD protein was also shown to be a cognate of α2-macroglobulin. Because the structure of both the 70 and 36 kD proteins suggested that protease activity and its inhibition might play a role in male mate choice, three protease inhibitors were tested in bioassays of male discrimination of conspecifics. The male's ability to discriminate among females was not completely blocked by the protease inhibitor, but their behavior was affected in more subtle ways. This suggests that the 70 kD protein, designated CSP70, is a variant of α2-macroglobulin, but with more specific activity.  相似文献   
15.
Adverse biological effects of ultraviolet-B (UV-B) radiation have been well documented for phytoplankton and zooplankton in both marine and freshwater ecosystems. However, investigations of interactions between UV-B and anthropogenic toxicants have focused primarily on the chemical interactions between UV-B and the toxicant. Here we investigate the potential for UV-B to increase the sensitivity of the rotifer Brachionus calyciflorus to either acute pentachlorophenol (PCP) or mercury toxicity, independent of UV-B effects on these toxicants. UV-B increased the toxicity of PCP and mercury to B. calyciflorus as much as five-fold, depending on duration of UV-B exposure and toxicant concentration. Reductions in the LC(50) of up to 60% were also seen for both toxicants. UV-B alone effectively eliminated B. calyciflorus reproduction and reduced ingestion by up to 90%. These results demonstrate the potential for UV-B to increase rotifer sensitivity to anthropogenic stressors independent of photochemical reactions with toxicants.  相似文献   
16.
A summary of the 209 PCB congener nomenclature   总被引:1,自引:0,他引:1  
Mills SA  Thal DI  Barney J 《Chemosphere》2007,68(9):1603-1612
Primary publications of congener numbering shorthand systems for PCB congener identification were reviewed, including the original Ballschmiter-Zell (BZ) system; recommended changes by Schulte and Malisch, and Guitart et al.; and listings by the Chemical Abstracts Service. Comparisons of the various congener numbering shorthands and chlorine substitution numberings in the structural name listings are presented. Several changes, to adhere more closely to IUPAC rules, have been incorporated into the BZ structural nomenclature, and these resulted in renumbering congeners. These corrected listings have been erroneously identified as "IUPAC" numbers, a misnomer, because IUPAC has not published a shorthand system. Guitart pointed out additional inconsistencies with IUPAC rules for nine congeners which would result in further order changes, but did not recommend renumbering, to avoid further confusion. We noted an additional error in the structural name for congener 97, named 2,2',3',4,5 using Ballschmiter and Zell nomenclature and 2,2',3,4',5' using strict IUPAC nomenclature. This renaming would cause the renumbering of the IUPAC number system reported by Guitart for isomers 91 through 98. No further changes are recommended, however. Tables summarizing each publication, and the discrepancies between them are provided in hopes of clarifying the current state of the nomenclature.  相似文献   
17.
Surface glycoproteins serve as mate- and gamete-recognition molecules in some marine animals such as rotifers and sea urchins. We investigated the role of contact chemoreception of surface glycoproteins in mate recognition, mate-guarding, and spermatophore transfer in the marine harpacticoid Tigriopus japonicus Mori. Adult males accurately distinguished immature females from a pool of mixed-sex juveniles, and their behavior towards both live and dead females is described. A survey of the binding sites of twelve lectins to the surface of juvenile and adult females, and adult males demonstrated localized lectin-binding at sites considered important in mating behavior of each sex/age class. Treating adult males with the Triticum vulgaris lectin sharply inhibited normal mate recognition and guarding behavior, as did the monosaccharide glucosamine. Treatment of males with protease and detergents destroyed their mate-guarding behavior without affecting swimming behavior. These results suggest that protein receptors on the antennules of the males detect glycoprotein signals on the surface of females, recognizing carbohydrate moieties of glycoproteins to identify appropriate partners for guarding or mating. Surface glycoproteins may function as a common mechanism of sexual communication in many marine zooplankters. Received: 6 May 1997 / Accepted: 14 September 1997  相似文献   
18.
We investigate the phylogeography of California (Zalophus californianus) and Galápagos (Z. wollebaeki) sea lions and describe within-population structure for the California sea lion based on mitochondrial DNA. Fifty control-region haplotypes were found, 41 from Z. californianus and 9 from Z. wollebaeki, with three fixed differences between the two species. Ranked population boundaries along the range of Z. californianus were defined based on the Monmonier Maximum Difference Algorithm, resulting in five genetically distinct populations, two in the Pacific Ocean and three inside the Gulf of California. A Minimum Spanning Network showed a strong phylogeographic signal with two well-defined clusters, Z. californianus and Z. wollebaeki, separated by six base-pair differences, supporting the existence of two genetically distinct species with an estimated divergence time of ~0.8 Ma. Results are discussed in the context of the historical geologic and paleoceanographic events of the last 1 Ma in the eastern Pacific.  相似文献   
19.
Increasing levels of household waste have raced up national, regional and municipal environmental policy agendas around the world, especially as heavy reliance on landfill and incineration is becoming prohibitively expensive and also a high profile source of local voter dissent or vociferous NIMBY behaviour. In an attempt to reduce reliance on these options, UK local authorities have increasingly been forced to turn to recycling. This paper reports on a broad empirical study of household recycling, utilizing national survey-based evidence (drawn from over 31 000 interviews in Scotland). Hitherto, very few published empirical studies have addressed the household recycling decision using national survey data to furnish baseline evidence. For this purpose logit analysis is undertaken, using data extracted from the Scottish Household Surveys of 2000 and 2001. This work also serves as the basis for further detailed modelling of a selection of illustrative household types. After consideration of particular waste streams and the availability of different recycling schemes, the effects on the probability of recycling participation of age, income level, household composition, car ownership and local authority were analysed. While there are clear income effects, the picture regarding the impact of household composition and some other factors is more complex.  相似文献   
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