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Many Other Species (many + other_species)
Selected AbstractsEffects of experimental small-scale grassland fragmentation on spatial distribution, density, and persistence of ant nestsECOLOGICAL ENTOMOLOGY, Issue 6 2003Brigitte Braschler Abstract., 1.,Grassland fragmentation is expected to influence the abundance of different invertebrate species to a different extent. Fragmentation-related effects are of particular importance in species that interact with many other species. 2.,The density and spatial distribution of nests of 15 ant species in experimentally fragmented calcareous grasslands at three sites in the Northern Swiss Jura mountains were examined. Fragments of different size (0.25 m2, 2.25 m2, and 20.25 m2) were isolated by a 5-m wide strip of frequently mown vegetation. Control plots of corresponding size were situated in adjacent undisturbed grassland. 3.,Three years after initiation of the experiment, ant nest density did not differ between fragments and control plots. Six years after initiation of the experiment, however, ant nest density and forager abundance were higher in large fragments than in large control plots. Ant nests tended to occur more frequently along the edge of fragments than in the core area. Persistence time of nests of the most abundant species, Lasius paralienus, tended to be shorter in fragments than in control plots. Furthermore, persistence time was longer in nests situated close to the fragment edge than in nests in the core area. 4.,Effects on nest density, edge effects on the spatial distribution of nests, and the relationships between nest density and environmental factors were more pronounced when only nests of L. paralienus were considered. The implications of these findings for plant and other invertebrate species are discussed. [source] Climate change and the future for coral reef fishesFISH AND FISHERIES, Issue 3 2008Philip L Munday Abstract Climate change will impact coral-reef fishes through effects on individual performance, trophic linkages, recruitment dynamics, population connectivity and other ecosystem processes. The most immediate impacts will be a loss of diversity and changes to fish community composition as a result of coral bleaching. Coral-dependent fishes suffer the most rapid population declines as coral is lost; however, many other species will exhibit long-term declines due to loss of settlement habitat and erosion of habitat structural complexity. Increased ocean temperature will affect the physiological performance and behaviour of coral reef fishes, especially during their early life history. Small temperature increases might favour larval development, but this could be counteracted by negative effects on adult reproduction. Already variable recruitment will become even more unpredictable. This will make optimal harvest strategies for coral reef fisheries more difficult to determine and populations more susceptible to overfishing. A substantial number of species could exhibit range shifts, with implications for extinction risk of small-range species near the margins of reef development. There are critical gaps in our knowledge of how climate change will affect tropical marine fishes. Predictions are often based on temperate examples, which may be inappropriate for tropical species. Improved projections of how ocean currents and primary productivity will change are needed to better predict how reef fish population dynamics and connectivity patterns will change. Finally, the potential for adaptation to climate change needs more attention. Many coral reef fishes have geographical ranges spanning a wide temperature gradient and some have short generation times. These characteristics are conducive to acclimation or local adaptation to climate change and provide hope that the more resilient species will persist if immediate action is taken to stabilize Earth's climate. [source] Climate change affects colonization dynamics in a metacommunity of three Daphnia speciesGLOBAL CHANGE BIOLOGY, Issue 6 2008FLORIAN ALTERMATT Abstract Climate change is expected to alter the range and abundance of many species by influencing habitat qualities. For species living in fragmented populations, not only the quality of the present patches but also access to new habitat patches may be affected. Here, we show that colonization in a metacommunity can be directly influenced by weather changes, and that these observed weather changes are consistent with global climate change models. Using a long-term dataset from a rock pool metacommunity of the three species Daphnia magna, Daphnia longispina and Daphnia pulex with 507 monitored habitat patches, we correlated a four-fold increase in colonization rate with warmer, drier weather for the period from 1982 to 2006. The higher colonization rate after warm and dry summers led to an increase in metacommunity dynamics over time. A mechanistic explanation for the increased colonization rate is that the resting stages have a higher exposure to animal and wind dispersal in desiccated rock pools. Although colonization rates reacted in the same direction in all three species, there were significant species-specific effects that resulted in an overall change in the metacommunity composition. Increased local instability and colonization dynamics may even lead to higher global stability of the metacommunity. Thus, whereas climate change has been reported to cause a unidirectional change in species range for many other species, it changes the dynamics and composition of an entire community in this metacommunity, with winners and losers difficult to predict. [source] Paddlefish Polyodon spathula juveniles food searching behaviour evoked by natural food odourJOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2007A. O. Kasumyan Summary Using the behavioural bioassay, food search behaviour was investigated in paddlefish Polyodon spathula juveniles (2.3, 3.0, 5.0, 15.0 and 35.0 cm TL; and 16, 23, 35, 50 and 130 days post-hatch respectively) evoked by Daphnia water extracts. Main characteristics of this behaviour were increased swimming speed, sinking to the lower water layer, short and straight trajectories in the odour cloud and opening of the mouth. These responses were seldom clearly pronounced and had a fairly short time-pattern. Biting and snapping, common in food search by many other species, were never observed. Ability to respond to food odour developed at the beginning of exogenous feeding. Olfactory sensitivity of P. spathula to natural food extract was relatively low, 10,1,10,2 g L,1, 2,3 orders of magnitude lower than in some sturgeons. It was concluded that olfaction plays a minor role in the food search behaviour of paddlefish. [source] Ecological factors drive differentiation in wolves from British ColumbiaJOURNAL OF BIOGEOGRAPHY, Issue 8 2009Violeta Muñoz-Fuentes Abstract Aim, Limited population structure is predicted for vagile, generalist species, such as the grey wolf (Canis lupus L.). Our aims were to study how genetic variability of grey wolves was distributed in an area comprising different habitats that lay within the potential dispersal range of an individual and to make inferences about the impact of ecology on population structure. Location, British Columbia, Canada , which is characterized by a continuum of biogeoclimatic zones across which grey wolves are distributed , and adjacent areas in both Canada and Alaska, United States. Methods, We obtained mitochondrial DNA control region sequences from grey wolves from across the province and integrated our genetic results with data on phenotype, behaviour and ecology (distance, habitat and prey composition). We also compared the genetic diversity and differentiation of British Columbia grey wolves with those of other North American wolf populations. Results, We found strong genetic differentiation between adjacent populations of grey wolves from coastal and inland British Columbia. We show that the most likely factor explaining this differentiation is habitat discontinuity between the coastal and interior regions of British Columbia, as opposed to geographic distance or physical barriers to dispersal. We hypothesize that dispersing grey wolves select habitats similar to the one in which they were reared, and that this differentiation is maintained largely through behavioural mechanisms. Main conclusions, The identification of strong genetic structure on a scale within the dispersing capabilities of an individual suggests that ecological factors are driving wolf differentiation in British Columbia. Coastal wolves are highly distinct and representative of a unique ecosystem, whereas inland British Columbia grey wolves are more similar to adjacent populations of wolves located in Alaska, Alberta and Northwest Territories. Given their unique ecological, morphological, behavioural and genetic characteristics, grey wolves of coastal British Columbia should be considered an Evolutionary Significant Unit (ESU) and, consequently, warrant special conservation status. If ecology can drive differentiation in a highly mobile generalist such as the grey wolf, ecology probably drives differentiation in many other species as well. [source] Growth and reproductive biology of the foxfish Bodianus frenchii, a very long-lived and monandric protogynous hermaphroditic labridJOURNAL OF FISH BIOLOGY, Issue 3 2010S. Cossington Samples of the foxfish Bodianus frenchii, collected over reefs on the lower west and south coasts of Western Australia, contained individuals ranging up to 78 years old. Although B. frenchii is far smaller than many other species within the Labridae, its maximum age is the greatest yet recorded for this highly speciose family and, together with Achoerodus gouldii, provides an example of a temperate hypsigenyine with exceptional longevity. Length and age compositions of females and males and the histological characteristics of gonads of a wide length range of individuals demonstrated that B. frenchii is a protogynous hermaphrodite. Furthermore, as, on both coasts, the length of the smallest male was greater than that at which all females had become mature, B. frenchii is a monandric protogynous hermaphrodite, i.e. all of its males are derived from functional females. Attainment of maturity by females is related more to length than age, whereas the reverse is true for sex change. On the basis of Schnute growth equations and length-to-body mass regression equations, the predicted length at age and body mass at length of fish on the south coast were greater than those on the west coast throughout life. Although B. frenchii spawns daily during the main spawning season, which extends from October to February on both coasts, its fecundity at any given length is substantially greater on the south than on the west coast. The more rapid growth of juveniles and earlier attainment of maturity by B. frenchii on the south coast than on the warmer west coast, together with maturation at a similar size on both coasts, run counter to the trends observed in many species and certain ecological theories regarding the relationships between life-cycle traits and latitude and temperature. The attainment by B. frenchii of a larger body length at age, of greater body mass at length and of greater fecundity at both length and body mass in fish on the south than on the west coast strongly suggests that conditions on the former, cooler coast are more favourable for this labrid, which belongs to a sub-genus whose other species typically live in cool, deep, temperate waters. [source] Increasing the impact of conservation projectsAMERICAN JOURNAL OF PRIMATOLOGY, Issue 5 2010Lou Ann Dietz Abstract To assure a future for endangered primates and many other species, we must develop and carry out projects for their conservation as quickly and effectively as possible, even with only limited information about the complex systems of biological, political, social, economic, and cultural factors influencing the conservation situation. Adaptive management, defined as the integration of design, management, and monitoring to systematically test assumptions to learn and adapt, provides practitioners a method for improving strategies to achieve and sustain the desired conservation impact. The Conservation Measures Partnership, a joint venture of conservation NGOs, developed the Open Standards for the Practice of Conservation, a freely available framework that guides practitioners through implementation of best conservation practices. Using this process, project teams are explicit about the assumptions behind the strategies they choose, and thus able to trace their successes and failures back to good or poor theory, implementation, or a combination of the two. The Open Standards comprise five steps that constitute the project management cycle: (1) Conceptualize what you will achieve in the context of where you are working,involves defining your project team, scope, vision, conservation targets, critical threats, and analyzing the situation; (2) Plan your actions and monitoring,involves developing an action plan including goals, strategies, assumptions, objectives, and activities; a monitoring plan including indicators for measuring the status of goals, objectives, and assumptions; and an operational plan specifying the resources needed; (3) Implement your actions and monitoring,includes developing and implementing detailed work plans and ensuring sufficient resources, capacity, and partners; (4) Analyze, use, and adapt,involves managing monitoring data, regular analysis to convert them to useful information, and adapting the project plans accordingly; and (5) Capture and share learning,involves sharing lessons with key external and internal udiences to promote a learning culture. Am. J. Primatol. 72:425,440, 2010. © 2010 Wiley-Liss, Inc. [source] | |||||||||||||