bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluating Genetic Diversity Associated with Propagation‐Assisted Restoration of American Shad
Authors: Brown B. L. , Gunter T. P. , Waters J. M. , Epifanio J. M.
Published: March 2003

Abstract: We investigated the conservation of genetic diversity during a restoration program for American shad (Alosa sapidissima) in Virginia ( U.S.A.). Restoration entailed capture of wild Pamunkey River shad broodstock followed by production and release of hatchery‐reared fry to supplement the nearly extinct James River shad population. To assess the baseline genetic diversity of donor and recipient populations, we used five tri‐ and tetra‐nucleotide microsatellite loci to test for genetic heterogeneity among yearly subsamples from both rivers and between early‐ and late‐spawning shad from the donor population. Tests for allelic heterogeneity between James River and Pamunkey shad subsamples yielded no significant genetic differentiation (χ 2 = 14.72, p = 0.132 and χ 2 = 10.24, p = 0.440, respectively). We detected no significant genetic divergence between early‐ and late‐spawning adults in Pamunkey River spawning aggregations in either year. The donor and recipient populations exhibited significant genetic differentiation (χ 2 = 27.4, p = 0.003), however, indicating that the stocking program carries a risk of outbreeding depression. Because the two river populations are genetically divergent, replenishment of the James population with Pamunkey fry may be detectable in the future as heterozygote deficits and linkage disequilibria in the James River population. In an analysis of broodstock and their hatchery‐reared progeny, microsatellites proved efficient for family analysis, unambiguously determining the parentage of 100% of the hatchery‐reared fry studied. Genetic analysis indicated that breeding procedures may result in high levels of reproductive variance.
Consequences of Succession on Extensively Grazed Grasslands for Central European Butterfly Communities: Rethinking Conservation Practices
Authors: Balmer Oliver , Erhardt Andreas
Published: March 2003

Abstract: Because of changes in land use, the quantity of extensively grazed or mown calcareous grasslands and their successional stages have drastically declined over the last few decades in Central Europe. Old fallow land has decreased most. It is often afforested or reconverted into extensively cultivated grassland because extensive cultivation is believed to be favorable for diversity and rare species conservation. The relative importance of fallow calcareous grasslands, however, has not been investigated fully and might be much underestimated. To evaluate the relative importance of extensively grazed pastures, early and old fallow land, and young forest, we examined populations of diurnal butterflies from 14 sites in the Swiss Jura Mountains. We used univariate, multivariate, and qualitative methods to compare the successional stages. The first 2–3 years of succession had little influence on the butterfly fauna. Therefore, pastures and early fallow land were treated as a single “early stage.” Old fallow land had significantly higher species richness (+32%) and heterogeneity (+65%) and hosted more Red List species (+48%) than the early stage. Young forest was depauperate in butterfly species. Further, cluster analysis and correspondence analysis showed a close resemblance of the sites of the early stage to each other and a clear difference from the sites of old fallow land. All differences were best explained by the successional age of the sites. Both early stage and old fallow land showed a high proportion (>25%) of stage‐specific species, but more threatened species were specific to old fallow land. We conclude that up to now the importance of old fallow land has been underestimated in conservation efforts in Central Europe. Contrary to the prevailing opinion, it is at least as important for butterflies as extensively cultivated grassland. Further conversion into forest, a common habitat in the region, should be prevented. Because old fallow land has become exceedingly rare, its inclusion in management plans is urgently needed. Otherwise, we may soon lose a valuable but often overlooked part of our biodiversity.
Training Captive‐Bred or Translocated Animals to Avoid Predators
Authors: Griffin Andrea S. , Blumstein Daniel T. , Evans Christopher S.
Published: March 2003

Abstract:Animal reintroductions and translocations are potentially important interventions to save species from extinction, but most are unsuccessful. Mortality due to predation is a principal cause of failure. Animals that have been isolated from predators, either throughout their lifetime or over evolutionary time, may no longer express appropriate antipredator behavior. For this reason, conservation biologists are beginning to include antipredator training in pre‐release preparation procedures. We describe the evolutionary and ontogenetic circumstances under which antipredator behavior may degenerate or be lost, and we use principles from learning theory to predict which elements can be enhanced or recovered by training. The empirical literature demonstrates that training can improve antipredator skills, but the effectiveness of such interventions is influenced by a number of constraints. We predict that it will be easier to teach animals to cope with predators if they have experienced ontogenetic isolation than if they have undergone evolutionary isolation. Similarly, animals should learn more easily if they have been evolutionarily isolated from some rather than all predators. Training to a novel predator may be more successful if a species has effective responses to similar predators. In contrast, it may be difficult to teach proper avoidance behavior, or to introduce specialized predator‐specific responses, if appropriate motor patterns are not already present. We conclude that pre‐release training has the potential to enhance the expression of preexisting antipredator behavior. Potential training techniques involve classical conditioning procedures in which animals learn that model predators are predictors of aversive events. However, wildlife managers should be aware that problems, such as the emergence of inappropriate responses, may arise during such training.
Scale‐Dependent Effects of Habitat Disturbance on Species Richness in Tropical Forests
Authors: Hamer K. C. , Hill J. K.
Published: March 2003

Abstract: Despite growing concern, no consensus has emerged over the effects of habitat modification on species diversity in tropical forests. Even for comparatively well‐studied taxa such as Lepidoptera, disturbance has been reported to increase and decrease diversity with approximately equal frequency. Species diversity within landscapes depends on the spatial scale at which communities are sampled, and the effects of disturbance in tropical forests have been studied at a wide range of spatial scales. Yet the question of how disturbance affects diversity at different spatial scales has not been addressed. We reanalyzed data from previous studies to examine the relationship between spatial scale and effects of disturbance on tropical‐forest Lepidoptera. Disturbance had opposite effects on diversity at large and small scales: as scale decreased, the probability of a positive effect of disturbance on diversity increased. We also explicitly examined the relationship between spatial scale and the diversity of butterflies in selectively logged and unlogged forest in Maluku Province, Indonesia. Species richness increased with spatial scale in both logged and unlogged forest, but at a significantly faster rate in unlogged forest, whereas species evenness increased with scale in unlogged forest but did not increase with scale in logged forest. These data indicate that the effects of habitat modification on species diversity are heavily scale‐dependent. As a result, recorded effects of disturbance were strongly influenced by the spatial scale at which species assemblages were sampled. Future studies need to account for this by explicitly examining the effects of disturbance at a number of different spatial scales. A further problem arises because the relationship between scale and diversity is likely to differ among taxa in relation to mobility. This may explain to some extent why the measured effects of disturbance have differed between relatively mobile and immobile taxa.
Amphibian Breeding and Climate Change
Authors: Blaustein Andrew R. , Belden Lisa K. , Olson Deanna H. , Green David M. , Root Terry L. , Kiesecker Joseph M.
Published: March 2003

Abstract: Climate changes may be influencing the breeding patterns of certain organisms. Effects on breeding activities could eventually lead to significant changes in population structure that may be reflected in population declines of species that are especially sensitive, such as some amphibians. Thus, climate changes may have affected the timing of breeding in some European amphibian species. To further test whether amphibian reproductive cycles in temperate countries are responding to climate changes, we conducted an analysis of the breeding phenology of four species of North American anurans for which we have long‐term data sets. Populations of at least two of these species have been declining, and it has been suggested that they and other amphibians may be especially sensitive to climate change. Our results suggest that climate change has not influenced the timing of breeding in amphibians in North America. At one site, in Oregon, a trend (nonsignificant) for western toads (  Bufo boreas) to breed increasingly early was associated with increasing temperature. At four other sites, however, neither western toads nor Cascades frogs (   Rana cascadae) showed statistically significant positive trends toward earlier breeding. At three of four of these sites, breeding time was associated with warmer temperatures. The spring peeper (   Pseudacris crucifer) in Michigan did not show a statistically significant trend toward breeding earlier but did show a significant positive relationship between breeding time and temperature. Fowler's toad (   Bufo fowleri) in eastern Canada did not show a trend toward breeding earlier, and there was no positive relationship between breeding time and temperature. It did however, show a strong but statistically insignificant trend toward breeding later. The broad pattern emerging from available studies is that some temperate‐zone anuran populations show a trend toward breeding earlier, whereas others do not. It is important to track the breeding patterns of amphibians with long‐term data sets to more fully understand how we can manage threatened populations.
Synergistic Interactions between Habitat Fragmentation and Fire in Evergreen Tropical Forests
Authors: Cochrane Mark A.
Published: March 2003

Abstract: The growing prevalence of fragmentation and fire in tropical forests makes it imperative to quantify changes in these disturbances and to understand the ways in which they interact across the landscape. I used a multitemporal series of Landsat images to study the incidence and coincidence of fire and fragmentation in two areas of Pará state in the eastern Brazilian Amazon: Tailândia and Paragominase. In both areas, deforestation and forest fires were quantified for time series of 6–10 years. The Tailândia study area typifies a landscape with the herringbone pattern of government‐settled colonists, and the Paragominas area is dominated by large cattle ranches. In both areas, over 90% of the forests affected by fire were associated with forest edges. Although most burned forest occurred within 500 m of forest edges, some fires occurred in deep forest, several kilometers from any edge. The obvious synergism between forest fragmentation and fire poses serious risks to tropical ecosystems and has important implications for land management.
Testing the Accuracy of Population Viability Analysis
Authors: McCarthy M. A. , Possingham H. P. , Day J. R. , Tyre A. J.
Published: March 2003

Abstract: Despite the growing use of population viability analysis ( PVA), the predictions of these models rarely have been tested with field data that were not used in initially developing the model. We review and discuss a suite of methods that may be used to test the predictive ability of models used in PVA. In addition to testing mean predictions, appropriate methods must analyze the probability distribution of the model predictions. The methods we discuss provide tests of the mean predictions, the predicted frequency of events such as extinction and colonization, and the predicted probability distribution of state variables. We discuss visual approaches based on plots of observations versus the predictions and statistical approaches based on determining significant differences between observations and predictions. The advantages and disadvantages of each method are identified. The best methods test the statistical distribution of the predictions; those that ignore variability are meaningless. Although we recognize that the quality of a model is not solely a function of its predictive abilities, tests help reduce inherent model uncertainty. The role of model testing is not to prove the truth of a model, which is impossible because models are never a perfect description of reality. Rather, testing should help identify the weakest aspects of models so they can be improved. We provide a framework for using model testing to improve the predictive performance of PVA models, through an iterative process of model development, testing, subsequent modification and re‐testing.
Experimental Evidence for Beneficial Fitness Effects of Gene Flow in Recently Isolated Populations
Authors: Newman Dara , Tallmon David A.
Published: March 2003

Abstract:A rich theory has been developed to explain the evolution of populations at equilibrium conditions of gene flow, inbreeding, and selection. There are, however, few empirical examples of the effects of gene flow into recently isolated, small populations under nonequilibrium conditions, such as are expected following population fragmentation. We studied the effects of inbreeding and gene flow in small, experimental populations of the mustardBrassica campestris(rapa). Replicate populations of five individuals randomly mated in a growth room received treatments of 0, 1, or 2.5 migrants each generation. Plants from the sixth experimental generation were planted in an outdoor common garden to evaluate the effects of the treatments on fitness and the distribution of phenotypic variation. Regression of six fitness components on inbreeding coefficients indicated a negative effect of inbreeding on fitness for five of these components. The 0‐migrant treatment had significantly lower fitness than the migrant treatments for four of six fitness components, but fitness did not differ between the 1‐migrant and 2.5‐migrant treatments. Phenotypic divergence among populations decreased with an increased number of migrants. These data provide empirical evidence of the beneficial fitness effects of a small number of migrants for recently fragmented populations.
History and Application of the Wilderness Concept in Marine Conservation
Authors: Sloan N. A.
Published: March 2003

Abstract: When applied to the sea, the wilderness concept of preserving large areas from human effects throws light on marine conservation ethics, pragmatism, and practice. I compared problems of land wilderness with those involving the sea, where social and technical preparedness for conservation lags behind that for the land. I describe marine applications related to wilderness and provide examples from various jurisdictions. Daunting marine attributes of scale, dynamism, and connectedness, as well as scientific and cultural uncertainty, weaken maritime application of the wilderness notion. Three main problems with this application are (1) protecting large enough areas, (2) defining desired marine ecosystem states with attendant roles for humans, and (3) addressing society's underdeveloped marine environmental awareness and ethics. The first relates to the practicality of establishing large preserved areas near populated compared with unpopulated areas. The second relates to accommodating coastal‐community subsistence given the ethics and realities of coastal poverty, indigenous peoples' status, and rural lifestyles. The third relates to public confusion over maritime governance, uncertainty over appropriate civility toward marine resources, and cultural expectations of freedom on the seas. These issues foster political indecision and strong opposition from some fishery and coastal‐community sectors to conservation of marine areas. Perhaps the value‐laden wilderness term still carries too much terrestrial preservationist baggage for sea areas that are viewed as commons by many. The wilderness ideal is but one point on a conservation continuum ranging from strict preservation to humans as part of nature. The laudable ideal of wilderness has a role in addressing the need for rapid progress in marine conservation, but we should be circumspect in applying the wilderness concept to the sea.
Spatial Autocorrelation Analysis and the Identification of Operational Units for Conservation in Continuous Populations
Authors: Diniz‐Filho José Alexandre Felizola , De Campos Telles Mariana Pires
Published: March 2003

Abstract: Despite recent advances in the identification of genetic population structure through molecular‐marker technology, the definition of intraspecific units for conservation remains problematic, particularly when genetic or phenotypic variation is continuously distributed in geographic space. We show that spatial autocorrelation analysis, applied to phenotypic or molecular data, can be used to describe the geographic structure and therefore can help define optimum strategies for conserving genetic variability within species. We propose that the intercept of a spatial correlogram can be an indication of the minimum distance between samples that can conserve and assess genetic diversity with maximum efficiency at lower costs. This parameter can be used both to define units and to establish sampling strategies for conservation programs. We illustrate the utility of this approach by autocorrelation analyses applied to three data sets: isozyme variability among Eugenia dysenterica populations in Brazilian Cerrado and within populations of Adenophora glandiflora in Korea, and microsatellite variation among Ursus arctos populations in North America. Our results suggest that the intercept of spatial correlograms is a useful parameter for establishing operational units for intraspecific conservation in continuous populations, based on overall genetic or phenotypic variability, by defining the minimum geographic distance at which samples are independent.
Local and Landscape‐Scale Predictors of Salamander Abundance in New Hampshire Headwater Streams
Authors: Lowe Winsor H. , Bolger Douglas T.
Published: March 2003

Abstract: We investigated the response of Gyrinophilus porphyriticus ( Plethodontidae), the spring salamander, to timber harvest in headwater streams in New Hampshire ( U.S.A.). We conducted cover‐controlled, whole‐stream surveys for G. porphyriticus in 25 first‐order streams in drainages encompassing a range of timber‐harvest histories. Streams in two different landscape configurations were chosen, isolated, or paired, based on the presence or absence of a confluent first‐order stream—a potential source of immigrants. We analyzed salamander abundance with respect to logging history, presence of the brook trout (  Salvelinus fontinalis), salamander population connectivity, and other measures of physical habitat and aquatic conditions. In stepwise multiple‐regression analysis, the best multivariate model of G. porphyriticus abundance included fish presence/absence; effect category, a combined function of years since harvest and substrate embeddedness by fine sediment; and landscape configuration. These three factors explained 74% of the variation in G. porphyriticus abundance. G. porphyriticus was less abundant in streams where fish were present, likely because of predation by S. fontinalis or asymmetric competition between these species. Abundance also declined with increasing substrate embeddedness and/or decreasing years since harvest, indicating an effect of fine sediment inputs and harvest history on this species. Finally, G. porphyriticus was less abundant in isolated streams than in paired streams. This result suggests that landscape‐scale population connectivity may buffer this species from the negative effects of local (i.e., stream‐scale) habitat perturbation. We hope this work will encourage others to develop multiscale models of land‐use effects on stream biota and thereby ultimately increase the range and effectiveness of conservation strategies for these species.
Good Medicine for Conservation Biology: the Intersection of Epidemiology and Conservation Theory
Authors: Lafferty Kevin D. , Gerber Leah R.
Published: March 2003

Abstract:Infectious disease can be a concern for several aspects of conservation biology, such as determining threats to species, estimating population viability, and designing reserves, captive breeding, and recovery programs. Several measures are useful for describing infectious diseases in host populations, but it is not straightforward to determine the degree to which a particular disease may affect a host population. The most basic epidemiological theory suggests that populations should be least subject to host‐specific infectious disease when they are at low abundance (  paradoxically, the state at which they are in most need of conservation action). There are important exceptions, however, such as when a reservoir host exists or when Allee or stochastic effects occur. Several of the key threats to biodiversity—habitat alteration, introduced species, pollution, resource exploitation, and climate change—can facilitate and/or impair transmission of infectious disease. Common management tools such as population viability analysis rarely address infectious disease explicitly. We suggest that such an inclusion is both possible and warranted. Considerations of infectious disease may influence the way we determine whether a species is in need of protection and how we might design reserves and captive breeding programs. Examples from the literature suggest that (1) introduced pathogens can make abundant species rare and (2) diseases of domestic animals can dramatically affect rare species. For both scenarios, conditions that cause stress or reduce genetic variation may increase susceptibility to disease, whereas crowding and cross‐species contact can increase transmission. Southern sea otters (   Enhydra lutris nereis) make an interesting case study for consideration of the intersection of epidemiology and conservation because disease may be an important factor limiting the growth of otter populations. We conclude that pathogens are of increasing concern for conservation. Because many newly emerging pathogen dynamics often do not conform to the simplifying assumptions used in classic epidemiology, a detailed understanding of pathogen life history will illuminate the intersection of epidemiology and conservation theory.
Effects of Land‐Use Intensity in Tropical Agroforestry Systems on Coffee Flower‐Visiting and Trap‐Nesting Bees and Wasps
Authors: Klein Alexandra‐Maria , Steffan‐Dewenter Ingolf , Buchori Damayanti , Tscharntke Teja
Published: March 2003

Abstract:Tropical landscapes are dominated by agroecosystems, and most species that survive in forest remnants interact with these agroecosystems. The potential value of agroecosystems for aiding species survival is often ignored. Essential ecosystem services may suffer when functional groups such as pollinators and predators are affected by land use. We used agroforestry systems differing in land‐use intensity to examine flower‐visiting bees on coffee plants and the community structure of trap‐nesting bees and wasps and their natural enemies. The number and abundance of all species of coffee‐visiting bees did not show a significant correlation with land‐use intensity. The abundance ( but not the number of species) of solitary bees increased with land‐use intensity, whereas the abundance and number of species of social bees significantly decreased. In a further experiment, abundance and number of trap‐nesting species increased with land‐use intensity. These results contrast with the common expectation that intensively used agroforestry systems are characterized only by loss of species. Furthermore, they support the idea that many nonpest and beneficial insect species may even profit from agricultural land use. Parasitism and predation of trap‐nest inhabitants did not change with land‐use intensity, but species diversity (number of enemy species) and ecological function (mortality) were correlated.
Competitive Abilities of Rare and Common Plants: Comparisons UsingAcaena(Rosaceae) andChionochloa(Poaceae) from New Zealand
Authors: Lloyd Kelvin M. , Lee William G. , Wilson J. Bastow
Published: March 2003

Abstract:It is commonly suggested that rare plant species are poor competitors. However, the study of rarity and competitive ability has, like much of the research on rare species, been hindered by insufficient sample size, scarce use of experimental methods, and lack of comparison with common species. We used a within‐taxon comparative approach to test for differences in competitive ability between rare and common species in two genera,Acaena( Rosaceae: six rare and four common species) andChionochloa( Poaceae: four rare and five common species). We grew plants in replicated experiments at two levels of soil fertility and with two levels of competition, in monoculture or mixed with the introduced grassAgrostis capillaris. Competitive response was measured as relative yield, relative tiller increase, and change in live‐leaf fraction. Rarity was measured by geographic range size, defined as the number of 10‐km grid squares occupied by each species in New Zealand. The relationship between competitive ability and geographic range size was tested with correlations. WithinAcaena, four of the rare species had high competitive ability, but there was no general relationship between competitive ability and rarity at either high or low levels of fertility. Differences in competitive ability appeared related to differences in ecological distribution rather than to rarity or commonness in a geographic sense. WithinChionochloa, common species tended to be stronger competitors than rare species, with the relationship being significant at the low level of fertility. Several of the commonChionochloaspecies have expanded their geographic ranges relatively recently, consistent with their greater competitive ability. Conversely, rareChionochloaspecies occupy specialized habitats that may be interpreted as refuges from competition. Disparate results fromAcaenaandChionochloado not support the notion that rare species are generally poor competitors. Although rare species may have low competitive ability in some cases, it should not be assumed to be a cause of rarity for all rare species.
Genetic Diversity in a Morphologically Conservative Invasive Taxon: Multiple Introductions of Swamp Eels to the Southeastern United States
Authors: Collins Timothy M. , Trexler Joel C. , Nico Leo G. , Rawlings Timothy A.
Published: March 2003

Abstract: Genetic analysis of introduced populations, especially in morphologically conservative taxa, can clarify introduction histories, identify management units and source populations, provide a more realistic estimate of the frequency of successful invasion, and suggest strategies for preventing further introductions. In the last 7 years, populations of swamp eels, referred to the Asian genus Monopterus ( Family Synbranchidae) on the basis of external morphology, have been discovered in aquatic habitats near Atlanta, Georgia; Tampa, Florida; North Miami, Florida; and most recently in close proximity to Everglades National Park in Homestead, Florida. Swamp eels are large predators capable of dispersal over land and have the potential to disrupt already threatened ecosystems. We analyzed mitochondrial DNA sequences from four known populations in the continental United States and samples from Malaysia, Indonesia, Vietnam, and two locations in China to determine introduction histories, source populations, genetic diversity, and relationships among populations. Our results indicate that there have been at least three independent introductions of genetically distinct forms. Introduced populations in close proximity (separated by <40 km) are genetically distinct. The level of sequence difference among introduced populations reaches levels seen among sister families of teleost fishes for the same region of the mitochondrial genome. These genetically distinct introduced populations in all likelihood represent at least two and possibly three species. Regardless of species status, these genetically distinct lineages may be expected to vary in ecological or life‐history traits, representing different potential threats to the ecosystems where they have been introduced. Given the success of swamp eels in invading many habitats around the world, further study of these eels is warranted to elucidate the characteristics of successful invaders and invasions.
Agroecology of Birds in Organic and Nonorganic Farmland
Authors: Beecher Nancy A. , Johnson Ron J. , Brandle James R. , Case Ronald M. , Young Linda J.
Published: March 2003

Abstract:Ecological relationships between wildlife conservation and farm management provide common ground for the enhancement of bird habitat and the natural suppression of pests on farmland. We compared bird populations in 15 paired organic and nonorganic sites (cornfields plus edges, 30 sites total) that were similar in environment and edge habitat but that differed in use of fertilizers, herbicides, cultivation, and crop rotations. At each site, we used one strip transect to sample birds and vegetation in the bordering edge and cornfield perimeter (0–25 m from the edge) and another to sample in the cornfield (50–150 m from the edge). During the 1995 and 1996 growing seasons, we recorded 54 bird species, 51 in organic and 39 in nonorganic sites. On average, bird abundance on organic sites was 2.6 times higher than on nonorganic sites, and mean species richness per visit was 2.0 times greater. When analyzed separately, organic edge, perimeter, and field transects supported higher bird abundance and greater richness than did their nonorganic counterparts. Abundance and richness were higher on organic sites for insectivores, omnivores, and granivores, and for each of three migratory groups. Twelve species were individually more abundant on organic sites, and one regularly observed species was observed only on organic sites. No species had greater abundance on nonorganic sites. More non‐crop vegetation on organic cornfields, most likely a result of no herbicide use, may have provided better foraging opportunities for birds. The plant food, cover, and invertebrate prey in organic cornfields appeared to augment birds not only in the field but also in the uncropped edges. Organic fields appear to benefit birds, but reproductive success needs further study. Modifying farm‐management practices, especially near field edges where bird activity is concentrated, may enhance the conservation of birds and their potential predation on crop pests.
Improving the Practice of Conservation: a Conceptual Framework and Research Agenda for Conservation Science
Authors: Salafsky Nick , Margoluis Richard , Redford Kent H. , Robinson John G.
Published: March 2003

Abstract: Effective conservation requires addressing three fundamental questions whose answers can only be sought in conservation practice: (1) What should our goals be and how do we measure progress in reaching them? (2) How can we most effectively take action to achieve conservation? and (3) How can we learn to do conservation better? This essay provides a conceptual framework and research agenda for a conservation science that uses the principles of adaptive management to answer these questions. The framework is based on a general model of a conservation project. The conservation target involves defining the specific area or population the project is trying to influence. This target is affected by direct and indirect threats and opportunities; we provide a table of potential direct threats. Conservation actions that are taken to counter these threats can be divided into approaches, strategies, and specific tools; we present a comprehensive table of potential approaches. Finally, the practicioners that take these actions include individuals, organizations, project alliances, and networks; we define the specific functional roles necessary to achieve effective adaptive management. We then use this framework to outline a research agenda for conservation science that involves defining clear and practical measures of conservation success, determining sound guiding principles for using conservation strategies and tools, and developing the knowledge and skills in individuals and organizations for good adaptive management and thus for making conservation more effective.
Improving U.S. Endangered Species Act Recovery Plans: Key Findings and Recommendations of the SCB Recovery Plan Project
Authors: Clark J. Alan , Hoekstra Jonathan M. , Boersma P. Dee , Kareiva Peter
Published: March 2003

Abstract: To promote more effective recovery planning for species listed under the U.S. Endangered Species Act ( ESA), the Society for Conservation Biology sponsored a systematic review of a large sample of ESA recovery plans. The review was conducted in collaboration with the U.S. Fish and Wildlife Service, the National Center for Ecological Analysis and Synthesis, and 19 universities. We describe the genesis of the project and the development of the resulting database of information on ESA recovery plans. The project's primary goals were to characterize the content and attributes of recovery plans; to identify important differences, patterns, and trends among plans; and to use these results to develop recommendations for the U.S. Fish and Wildlife Service for improving recovery plans. We review key findings from published analyses of the project database and offer prioritized recommendations for improving recovery‐plan development and implementation. First, the use of science in recovery‐plan development and implementation could be improved by making threats a primary focus of plans, specifying adequate monitoring tasks for species status and recovery tasks, and ensuring that species trend data are current, quantitative, and documented. Second, recovery‐plan structure and development could be enhanced by keeping authorship teams small yet diverse, making existing administrative designations more biologically relevant, improving and standardizing the revision process, and reevaluating the use of multispecies plans. Third, agency resources and personnel could be better utilized by developing new recovery plan guidelines, assigning personnel explicit responsibility for overseeing plan implementation, expanding personnel training, and tracking expenditures in recovery programs. And fourth, several generic failings in the field of conservation biology could be addressed by reducing taxonomic bias and by collecting and fully integrating key biological information into recovery plans. The recovery‐plan project offers a model of how professional societies, universities, and government agencies can work together beneficially to address key issues in conservation biology.
Optimizing Habitat Protection Using Demographic Models of Population Viability
Authors: Haight Robert G. , Cypher Brian , Kelly Patrick A. , Phillips Scott , Possingham Hugh P. , Ralls Katherine , Starfield Anthony M. , White P. J. , Williams Daniel
Published: March 2003

Abstract:Expanding habitat protection is a common tactic for species conservation. When unprotected habitat is privately owned, decisions must be made about which areas to protect by land purchase or conservation easement. To address this problem, we developed an optimization framework for choosing the habitat‐protection strategy that minimizes the risk of population extinction subject to an upper bound on funding. The framework is based on the idea that an extinction‐risk function that predicts the relative effects of varying the quantity and quality of habitat can be estimated from the results of a demographic model of population viability. We used the framework to address the problem of expanding the protected habitat of a core population of the endangered San Joaquin kit fox (   Vulpes macrotis mutica) in the Panoche area in central California. We first developed a stochastic demographic model of the kit fox population. Predictions from the simulation model were used to estimate an extinction‐risk function that depended on areas of good‐ and fair‐quality habitat. The risk function was combined with costs of habitat protection to determine cost‐efficient protection strategies and risk‐cost curves showing how extinction risk could be reduced at minimum cost for increasing levels of funding. One important result was that cost‐efficient shares of the budget used to protect different types of habitat changed as the budget increased and depended on the relative costs of available habitat and the relative effects of habitat protection on extinction risk. Another important finding was the sensitivity of the location and slope of the risk‐cost curve to assumptions about the spatial configuration of available habitat. When the location and slope of the risk‐cost curve are sensitive to model assumptions, resulting predictions of extinction risk and risk reduction per unit cost should be used very cautiously in ranking conservation options among different species or populations. The application is an example of how the results of a complex demographic model of population viability can be synthesized for use in optimization analyses to determine cost‐efficient habitat‐protection strategies and risk‐cost tradeoffs.
Deleterious Effects of Restricted Gene Flow in Fragmented Populations
Authors: Couvet Denis
Published: March 2003

Abstract: I examined the expected detrimental effects of restricted gene flow, a consequence of population fragmentation, through a population genetics model. The model predicts the frequency of deleterious mutations and the viability of the individuals in a set of populations, depending on the number of migrants per generation per population. When the number of migrants is lower than one per generation, a large increase in the viability of the individuals along with the number of migrants is expected. With one migrant per generation, detrimental genetic effects on population survival are expected for low population size or low population growth rate. Finally, the negative effects of restricted gene flow depend not only on the number of migrants entering the population considered but also on the number of migrants entering the populations where the migrants came from.
Effect of Forest Fragmentation on Lyme Disease Risk
Authors: Allan Brian F. , Keesing Felicia , Ostfeld Richard S.
Published: March 2003

Abstract:Forest destruction and fragmentation in the United States recently have been shown to reduce mammalian species diversity and to elevate population densities of white‐footed mice (   Peromyscus leucopus ). One potential consequence of reduced species diversity and high mouse density in small fragments is an increase in human exposure to Lyme disease. Increased risk of exposure to this disease is expected because of the role of the white‐footed mouse as the principal natural reservoir of the Lyme bacterium,Borrelia burgdorferi. Blacklegged ticks (  Ixodes scapularis ) feeding on mice have a higher probability of becoming infected with the bacterium than do ticks feeding on any other host species. We hypothesized that small forest patches (  <2 ha ) have a higher density of infected nymphal blacklegged ticks, which is the primary risk factor for Lyme disease, than larger patches (  2–8 ha ). In the summer of 2000, we sampled tick density andB. burgdorferiinfection prevalence in 14 maple‐dominated forest patches, ranging in size from 0.7 to 7.6 ha, in Dutchess County of southeastern New York state. We found a significant linear decline in nymphal infection prevalence with increasing patch area and a significant exponential decline in nymphal density with increasing patch area. The consequence was a dramatic increase in the density of infected nymphs, and therefore in Lyme disease risk, with decreasing forest patch size. We did not observe a similar relationship between the density of larval ticks and patch size. These results suggest that by influencing the community composition of vertebrate hosts for disease‐bearing vectors, habitat fragmentation can influence human health.
Deforestation Trends in a Tropical Landscape and Implications for Endangered Large Mammals
Authors: Kinnaird Margaret F. , Sanderson Eric W. , O'Brien Timothy G. , Wibisono Hariyo T. , Woolmer Gillian
Published: March 2003

Abstract:The remarkable large‐mammal fauna of the Indonesian island of Sumatra is one of the most endangered on Earth and is threatened by rampant deforestation. We used remote sensing and biological surveys to study the effects of deforestation on populations of endangered large mammals in a Sumatran landscape. We measured forest loss and created a predictive model of deforestation for Bukit Barisan Selatan National Park and an unprotected buffer area based on satellite images between 1985 and 1999. We used automatic cameras to determine the distribution and relative abundance of tigers (   Panthera tigris sumatrae ), elephants (  Elephas maximus ), rhinoceros (  Dicerorhinus sumatrensis ), and tapirs (  Tapir indicus ). Between 1985 and 1999, forest loss within the park averaged 2% per year. A total of 661 km 2of forest disappeared inside the park, and 318 km 2were lost in a 10‐km buffer, eliminating forest outside the park. Lowland forest disappeared faster than hill/montane forest (  by a factor of 6  ) and forests on gentle slopes disappeared faster than forests on steep slopes (  by a factor of 16  ). Most forest conversion resulted from agricultural development, leading to predictions that by 2010 70% of the park will be in agriculture and that by 2036 lowland forest habitat will be eliminated. Camera‐trap data indicated avoidance of forest boundaries by tigers, rhinoceroses ( up to 2 km ), and elephants ( up to 3 km ). Classification of forest into core and peripheral forest based on mammal distribution suggests that, by 2010, core forest area for tigers and rhinoceros will be fragmented and reduced to 20% of remaining forest. Core forest area for elephants will be reduced to 0.5% of remaining forest. Halting forest loss has proven one of the most difficult and complex problems faced by Indonesia's conservation agencies today and will require a mix of enforcement, wise land‐use strategies, increased education, capacity to manage, and new financing mechanisms.
What Determines Quality in Maternity Care? Comparing the Perceptions of Childbearing Women and Midwives
Authors: Proctor Sue
Published: March 2003

Background:

In the current climate of consumer orientation in health care services, a clear need has emerged to understand the extent of consumer focus among primary health care professionals. Few studies have compared the beliefs of health care staff with those of patients. This study sought to identify and compare the perceptions of women and midwives concerning women's beliefs about what constitutes quality in maternity services.

Methods:

Focus groups were conducted from July 1994 to June 1997 with 38 pregnant and postnatal women, and 47 midwives who were based in two large maternity units in Yorkshire, England. Transcriptions of data were analyzed to identify broad themes.

Results:

Ten dimensions of quality were identified. Similarities between midwives and women included beliefs about the importance of the relationship between the two parties, desired attributes of staff, and the environment of care. Key differences included underestimating the importance of information antenatally and postnatally, the importance of continuity during labor, need for control and confidence in adjusting to the maternal role, and involvement of the woman's partner in the delivery of care.

Conclusions:

An understanding of the concerns of women by maternity care staff is important in the development of a woman‐focused service, in line with current policy recommendations, and has implications for risk management and improving the service quality for those who provide and experience the service. (BIRTH 25:2 June 1998)
Perceptions of Bed Rest by Women with High‐Risk Pregnancies: A Comparison Between Home and Hospital
Authors: Heaman Maureen , Gupton Annette ,   Maureen Heaman is Director of Research, Winnipeg Community and Long‐Term Care Authority, and Adjunct Professor in the Faculty of Nursing, University of Manitoba; Annette Gupton is an Associate Professor in the Faculty of Nursing, University of Manitoba, Winnipeg, Manitoba, Canada.
Published: March 2003

Background:
Bed rest at home or in the hospital is a commonly prescribed treatment for women experiencing complications of pregnancy. This focused ethnographic study examined bed rest from the high‐risk pregnant woman's perspective and compared perceptions of women cared for in the home with those in hospital.
Methods:
A convenience sample of 24 pregnant women who had been on bed rest for at least seven days was recruited from the antepartum unit of a tertiary care hospital and from an antepartum home care program in western Canada. Data were collected in 1994 through interviews and participant diaries. Content analysis was used to identify themes.
Results:
Bed rest had a significant emotional and social impact on pregnant women and their families in both settings. Overall, bed rest in hospital seemed to be associated with more sources of stress than at home. In hospital, women had to cope with separation from home and family, lack of privacy, hospital discomforts, and incompatible roommates, whereas women at home struggled with role reversal and the temptation to do more activity than was recommended. Stressors not unique to but exacerbated by hospitalization included concerns about the children, a sense of missing out, a sense of confinement and being a prisoner, boredom, feelings of depression and loneliness, and negative impact on the relationship with their partner.
Conclusion:
Study findings raise questions about the appropriateness of routine prescription of bed rest. Health care professionals should propose and develop home care programs as an alternative to antepartum hospitalization. (BIRTH 25:4 December 1998)