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1.
The REEF Fish Survey Project is a volunteer fish monitoring program developed by the Reef Environmental Education Foundation (REEF). REEF volunteers collect fish distribution and abundance data using a standardized visual method during regular diving and snorkeling activities. Survey data are recorded on preprinted data sheets that are returned to REEF and optically digitized. Data are housed in a publicly accessible database on REEF's Web site (http: //www.reef.org). Since the project's inception in 1993, over 40,000 surveys have been conducted in the coastal waters of North America, tropical western Atlantic, Gulf of California and Hawaii. The Fish Survey Project has been incorporated into existing monitoring programs through partnerships with government agencies, scientists, conservation organizations, and private institutions. REEF's partners benefit from the educational value and increased stewardship resulting from volunteer data collection. Applications of the data include an evaluation of fish/habitat interactions in the Florida Keys National Marine Sanctuary, the development of a multi-species trend analysis method to identify sites of management concern, assessment of the current distribution of species, status reports on fish assemblages of marine parks, and the evaluation of no-take zones in the Florida Keys. REEF's collaboration with a variety of partners, combined with the Fish Survey Project's standardized census method and database management system, has resulted in a successful citizen science monitoring program.  相似文献   
2.
It is increasingly obvious that social science, while not a sufficient condition for making ecosystem management effective, is a necessary condition. A social science typology of ecosystems is developed, applied, and shown to have substantial and unexpected implications for the practice of ecosystem management. Ecologists and environmental scientists, in particular, will find some conclusions uncomfortable. The application involves a case material from the California northern spotted owl controversy.  相似文献   
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4.
The links between children's rights and their participation in environmental decision-making is a growing field of interest. This paper describes findings from a six-month in-depth pilot study with a small group of children aged 6-10 years located in a village in the northeast of England. The focus of this paper is on the relationship of these children with their local landscape and how they felt about involvement in decision-making that might affect that environment. The methodology was child-centred responding to the 'languages' of children. Two main findings are discussed in this paper: (a) issues of boundary were particularly important in physical and emotional terms for both children and parents and this had little to do with the rurality of the location; (b) children believe they have special knowledge about the environment, which they may express using a range of communication methods. The author reflects on what implications this might have for the design and layout of local environments generally.  相似文献   
5.
In the current paper, we studied downtime at work. Downtime represents a unique aspect of work time, as employees have low workload and more discretion about their activities but are still paid to be at work. Despite its prevalence and potentially significant implications for productivity and well‐being, the experience of downtime has not been a focus in the literature. To study this phenomenon, we first used a qualitative method involving 15 focus groups. Results from 95 employees showed that downtime is distinct from formal breaks and withdrawal behavior and is generally a negative subjective experience. Categories of antecedents of experience and downtime activities were classified. Next, to further explore the phenomenon, and based on Study 1 and relevant literature, we proposed several hypotheses and tested them using an experience sampling method. Results from 86 employees (across 5 workdays and 689 data points) indicated that the amount of downtime was negatively related to day level job satisfaction, job performance, and subjective health. The duration of relaxation activities during downtime mitigated the negative effects of downtime on fatigue. The effects of enjoyment level of the activities, job autonomy, work engagement, and boredom proneness were also examined. Implications, limitations, and future research are discussed.  相似文献   
6.
In most species, only one sex searches for mates while the other waits. Models of sex-specific mate-searching behavior predict single-sex searching, but the factors that determine which sex searches are not understood. In this study, we examine the effects of density and predation risk on mate-searching behavior in the fiddler crab Uca beebei. U. beebei is one of the few fiddler-crab species in which both sexes search for mates. In a field experiment conducted in Panama, we manipulated crab density and perceived predation risk in replicate plots. Females searched more and males searched less at high densities. At high levels of perceived predation risk, both sexes similarly reduced their search rates. Observations of plots that naturally varied in crab density show that females were more likely to search for mates in areas of higher density, where there were more males. Females may preferentially search for mates in high-density areas because the abundance of nearby burrows, into which they can run to escape predators, decreases their costs of searching and because the abundance of males and male burrows facilitates comparisons and thus may increase their benefits from searching. Males at high densities decrease their mate-searching rate perhaps in response to the increase in female searching and to the corresponding increase in the intensity of their competitors' mate-attraction signals.  相似文献   
7.
Can Eco-Labels Tune a Market? Evidence from Dolphin-Safe Labeling   总被引:1,自引:0,他引:1  
In this paper we test whether the dolphin-safe labels altered consumer purchases of tuna. We also provide a partial measure of the total welfare effects of the dolphin-safe labeling policy. The results confirm our hypothesis that the dolphin–tuna controversy and the subsequent implementation of dolphin-safe labeling affected consumer behavior. Further, the paper provides market-based evidence that consumers can respond to eco-labels; the dolphin-safe label increased the market share of canned tuna. The welfare analysis provides a partial measure of society's willingness to pay to avoid personally contributing to dolphin mortality as a result of tuna fishing.  相似文献   
8.
The relationship between the vertical distributions of euphausiids and fish and light intensity has been studied directly by using a photometer in conjunction with an acoustically controlled rectangular midwater trawl. Samples were taken at a position centered on 47°N; 17°W on 15 and 16 May 1978. Five species of euphausiid and six species of fish have been analysed, both groups contained migrant and non-migrant species. The population of each of these species occurred throughout a light regime spanning at least three orders of magnitude of intensity; none of them was restricted to, or followed, and isolume. There were no sexual or size differences in the distributions of the euphausiids, but the population of Argyropelecus hemigymnus was probably stratified during the day, with smaller individuals occurring shallower than large ones. The results are discussed in relation to previous observations and to the theories of photic regulation of distributions and migrations.  相似文献   
9.
Roe AM  Meyer CB  Nibbelink NP  Ben-David M 《Ecology》2010,91(11):3177-3188
We explored the interacting effects of marine-derived nutrient fertilization and physical disturbance introduced by coastal river otters (Lontra canadensis) on the production and nutrient status of pristine shrub and tree communities in Prince William Sound, Alaska, USA. We compared production of trees and shrubs between latrines and non-latrines, while accounting for otter site selection, by sampling areas on and off sites. Nitrogen stable isotope analysis (delta15N) indicated that dominant tree and shrub species assimilated the marine-derived N excreted by otters. In association with this uptake, tree production increased, but shrub density and nonwoody aboveground shrub production decreased. The reduced shrub production was caused by destruction of ramets, especially blueberry (Vaccinium spp.), through physical disturbance by river otters. False azalea (Menziesia ferruginea) ramets were less sensitive to otter disturbance. Although surviving individual blueberry ramets showed a tendency for increased production per plant, false azalea allocated excess N to storage in leaves rather than growth. We found that plant responses to animal activity vary among species and levels of biological organization (leaf, plant, ecosystem). Such differences should be accounted for when assessing the influence of river otters on the carbon budget of Alaskan coastal forests at the landscape scale.  相似文献   
10.
Female rhesus macaques exhibit matrilineal dominance structures, and high dominance rank confers fitness benefits across a lifetime and across generations. Rank effects are “inherited” through social processes that are well understood; however, biological mechanisms that might impact these processes are not well known. Recently, it has been shown that prenatal androgens appear to be implicated in supporting dominance rank hierarchies in some mammals. In humans, interindividual differences in the second (index) to fourth (ring) digit ratio (2D:4D) have been linked indirectly to variation in prenatal androgens, with low 2D:4D in both sexes associated with higher inferred prenatal androgen effects. 2D:4D has also been related to dominant social behavior and has been shown to co-vary with social systems across nonhuman primate species. Here, we investigate how 2D:4D co-varies with socially inherited dominance rank in female rhesus macaques. Low 2D:4D was associated with higher-ranking females, while higher 2D:4D was associated with lower-ranking females. Similar relationships were also shown between ranked families within matrilines. This is the first study to show such a relationship between 2D:4D and dominance rank in a nonhuman primate and suggests that prenatal androgen effects could be involved in the maintenance of dominance rank in female cercopithecine primates.  相似文献   
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