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261.
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263.
Comparative use of shelter use by three sympatric species of combtooth blenny (Ecsenius stictus, Glyptoparus delicatulus, and Salarias patzneri) was studied among micro-atolls in the lagoon at Lizard Island (14°42′S, 145°30′E), northern Great Barrier Reef, Australia. Blenny species used different sized holes; however, the average diameter and depth of holes used by the smallest and largest species differed by only 4 and 25 mm, respectively, indicating interspecific differences in suitable refuge can be very subtle. Both hole diameter and depth were positively related to total length of fish, suggesting use of holes relates to interspecific differences in body size. Total abundance of blennies was best explained by a general linear model that included either the number of holes or total habitat area on individual micro-atolls, predictor variables that were positively correlated with each other. However, the relative importance of variables differed among the three species, feeding area being most important for S. patzneri, feeding area and number of holes for E. stictus, and variance in hole diameter being the best explanatory variable for G. delicatulus abundance. The number of blenny species on a micro-atoll was best explained by variance in hole diameter, emphasizing the influence of refuge size variety in fish diversity. It is likely that subtle habitat partitioning, which relates to interspecific differences in body size, contributes to the co-existence of blenny species within the same microhabitat, but presence of holes is unlikely to regulate abundance of these fish. 相似文献
264.
When three per cent may not be three per cent; device-equipped seabirds experience variable flight constraints 总被引:1,自引:1,他引:0
Current guidelines for instrumenting birds state that external devices should not exceed 3–5% of the birds’ body mass; however,
the energetic consequences of carrying any given device mass are likely to vary according to the morphology and ecology of
the species concerned. We used a freeware program to estimate the mechanical power requirements of flight at the minimum power
speed for 80 species of flying seabird from 8 major groups with payloads of increasing mass. Devices representing 3% of the
bird’s body mass resulted in an increase in energy expenditure for flight ranging from 4.67 to 5.71% without accounting for
the increase in body drag coefficient associated with external devices. This effect differed within and between seabird lineages
with members of the Alcidae and Phalacrocoracidae experiencing the highest energetic costs of any increase in device mass.
We propose that device effects on seabirds could be further reduced through consideration of species-specific effects of added
payload and drag. 相似文献
265.
S. K. Wilson C. J. Fulton M. Depczynski T. H. Holmes M. M. Noble B. Radford P. Tinkler 《Marine Biology》2014,161(11):2597-2607
Habitat shifts play an important role in structuring faunal assemblages; however, research has focused on the influence of random disturbance events and information on how regular seasonal changes to habitat affect marine fauna remains largely unexplored, especially in the tropics. We recorded seasonal changes in the structure of tropical macroalgae fields within the Ningaloo lagoon (Western Australia) and related this to the density, biomass and species richness of fishes that represent key processes: juveniles, predators of juveniles and herbivores. The extent and direction of seasonal changes in macroalgae were inconsistent among sites, creating a highly dynamic habitat matrix across time and space. Species richness and density of fishes were largely maintained where density of holdfasts from canopy-forming macroalgae and/or cover was high across seasons, but shifted markedly in areas of macroalgae habitat loss: suggesting stable habitat structure is critical for the persistence of macroalgae-associated fishes. Our results demonstrate that macroalgae fields that maintain high structural complexity across different seasons are more likely to preserve key ecological processes and therefore warrant greater conservation attention within a spatial management framework. 相似文献
266.
Kay Boulton Andrew J. Grimmer Gil G. Rosenthal Craig A. Walling Alastair J. Wilson 《Behavioral ecology and sociobiology》2014,68(5):791-803
Many studies have revealed repeatable (among-individual) variance in behavioural traits consistent with variation in animal personality; however, these studies are often conducted using data collected over single sampling periods, most commonly with short time intervals between observations. Consequently, it is not clear whether population-level patterns of behavioural variation are stable across longer timescales and/or multiple sampling periods or whether individuals maintain consistent ranking of behaviours (and/or personality) over their lifetimes. Here, we address these questions in a captive-bred population of a tropical freshwater poeciliid fish, Xiphophorus birchmanni. Using a multivariate approach, we estimate the among-individual variance-covariance matrix (I), for a set of behavioural traits repeatedly assayed in two different experimental contexts (open-field trials, emergence and exploration trials) over long-term (56 days between observations) and short-term (4-day observation interval) time periods. In both long- and short-term data sets, we find that traits are repeatable and the correlation structure of I is consistent with a latent axis of variation in boldness. While there are some qualitative differences in the way individual traits contribute to boldness and a tendency towards higher repeatabilities in the short-term study, overall, we find that population-level patterns of among-individual behavioural (co)variance to be broadly similar over both time frames. At the individual level, we find evidence that short-term studies can be informative for an individual’s behavioural phenotype over longer (e.g. lifetime) periods. However, statistical support is somewhat mixed and, at least for some observed behaviours, relative rankings of individual performance change significantly between data sets. 相似文献
267.
268.
Ryan Perkl David Mitchell Mark Feller Garrett Smith Natalie R. Wilson 《Journal of Land Use Science》2018,13(1-2):102-117
Urban and exurban expansion results in habitat and biodiversity loss globally. We hypothesize that a coupled-model approach could connect urban planning for future cities with landscape ecology to consider wildland habitat connectivity. Our work combines urban growth simulations with models of wildlife corridors to examine how species will be impacted by development to test this hypothesis. We leverage a land use change model (SLEUTH) with structural and functional landscape-connectivity modeling techniques to ascertain the spatial extent and locations of connectivity related threats to a national park in southern Arizona, USA, and describe how protected areas might be impacted by urban expansion. Results of projected growth significantly altered structural connectivity (80%) when compared to current (baseline) corridor conditions. Moreover, projected growth impacted functional connectivity differently amongst species, indicating resilience of some species and near-complete displacement of others. We propose that implementing a geospatial-design-based model will allow for a better understanding of the impacts management decisions have on wildlife populations. The application provides the potential to understand both human and environmental impacts of land-system dynamics, critical for long-term sustainability. 相似文献
269.
Alexander D. M. Wilson Robert L. McLaughlin 《Behavioral ecology and sociobiology》2010,64(11):1905-1914
Recently emerged brook charr (Salvelinus fontinalis) foraging in still-water pools along the sides of streams are either active, feeding on insects from the upper portion of
the water column away from the stream bank, or sedentary, feeding on crustaceans emerging from the hyporheic zone near the
stream bank. We tested whether the frequency of movement displayed by individual brook charr searching for prey in the field
was related to the relative volume of the telencephalon, a brain region involved with movement and space use in fishes. Movement
of individuals searching for prey was quantified in the field, individuals were captured and volumes of the telencephalon
and of the olfactory bulbs, a brain region neighbouring the telencephalon but not implicated in space use, were measured.
Individuals with larger telencephalon volumes moved more frequently on average while searching for prey in the field than
did individuals with smaller telencephalon volumes. The frequency of movement was unrelated to differences in the volume of
the olfactory bulbs, suggesting that the relationship between telencephalon volume and movement was not a consequence of differences
in overall brain size. Demonstrating a correlation between foraging behaviour and brain morphology for brook charr exhibiting
different foraging tactics suggests that diversification in brain structure and function could be important aspects of the
foraging specialization believed to occur during early stages in the evolution and development of resource polymorphisms. 相似文献
270.
Alexander D. M. Wilson Emily M. Whattam Rachel Bennett Laksanavadee Visanuvimol Chris Lauzon Susan M. Bertram 《Behavioral ecology and sociobiology》2010,64(5):703-715
Recently, there has been increasing interest in behavioral syndrome research across a range of taxa. Behavioral syndromes
are suites of correlated behaviors that are expressed either within a given behavioral context (e.g., mating) or between different
contexts (e.g., foraging and mating). Syndrome research holds profound implications for animal behavior as it promotes a holistic
view in which seemingly autonomous behaviors may not evolve independently, but as a “suite” or “package.” We tested whether
laboratory-reared male and female European house crickets, Acheta domesticus, exhibited behavioral syndromes by quantifying individual differences in activity, exploration, mate attraction, aggressiveness,
and antipredator behavior. To our knowledge, our study is the first to consider such a breadth of behavioral traits in one
organism using the syndrome framework. We found positive correlations across mating, exploratory, and antipredatory contexts,
but not aggression and general activity. These behavioral differences were not correlated with body size or condition, although
age explained some of the variation in motivation to mate. We suggest that these across-context correlations represent a boldness
syndrome as individual risk-taking and exploration was central to across-context mating and antipredation correlations in
both sexes. 相似文献