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In this article, we consider the potential effects of anthropogenic disturbances on marine fish species known or suspected to be habitat engineers. The three species of interest inhabit different marine habitats at different life stages, and therefore can have significant influences across the sea floor at broad spatial scales. The primary species include the shallow-water Atlantic goliath grouper (Epinephelus itajara), which inhabits mangrove root systems as juveniles, and caves, shipwrecks, and rocky reefs as adults; red grouper (E. morio), which excavates habitat throughout its benthic life in Karst regions of the Gulf of Mexico and western Atlantic, from the coast to the shelf-edge; and tilefish (Lopholatilus chamaeleonticeps), a species that lives on the continental slope and constructs elaborate, pueblo-esque burrows. The anthropogenic disturbances of greatest interest in the Gulf of Mexico include fishing, hypoxia, red tide, oil and gas exploration, and climatic change. We suggest that to understand the broader effects of both natural and anthropogenic disturbances on biomass and productivity in these species requires that we first understand the strength of interactions between them and the other species residing within their communities (e.g., predators, prey, commensals, and mutualists). doi: 10.1093/icb/icq072

Ecologists have long known that certain organisms fundamentally modify, create, or define habitats by altering the habitat's physical properties. In the past 15 years, these processes have been formally defined as 'ecosystem engineering', reflecting a growing consensus that environmental structuring by organisms represents a fundamental class of ecological interactions occurring in most, if not all, ecosystems. Yet, the precise definition and scope of ecosystem engineering remains debated, as one should expect given the complexity, enormity, and variability of ecological systems. Here I briefly comment on a few specific current points of contention in the ecosystem engineering concept. I then suggest that ecosystem engineering can be profitably subdivided into four narrower functional categories reflecting four broad mechanisms by which ecosystem engineering occurs: structural engineers, bioturbators, chemical engineers, and light engineers. Finally, I suggest some conceptual model frameworks that could apply broadly within these functional groups. doi: 10.1093/icb/icq077

Varietal data from 27 crop species from five continents were drawn together to determine overall trends in crop varietal diversity on farm. Measurements of richness, evenness, and divergence showed that considerable crop genetic diversity continues to be maintained on farm, in the form of traditional crop varieties. Major staples had higher richness and evenness than nonstaples. Variety richness for clonal species was much higher than that of other breeding systems. A close linear relationship between traditional variety richness and evenness (both transformed), empirically derived from data spanning a wide range of crops and countries, was found both at household and community levels. Fitting a neutral 'function' to traditional variety diversity relationships, comparable to a species abundance distribution of 'neutral ecology,' provided a benchmark to assess the standing diversity on farm. In some cases, high dominance occurred, with much of the variety richness held at low frequencies. This suggested that diversity may be maintained as an insurance to meet future environmental changes or social and economic needs. In other cases, a more even frequency distribution of varieties was found, possibly implying that farmers are selecting varieties to service a diversity of current needs and purposes. Divergence estimates, measured as the proportion of community evenness displayed among farmers, underscore the importance of a large number of small farms adopting distinctly diverse varietal strategies as a major force that maintains crop genetic diversity on farm. conservation on farm | diversity estimates | traditional varieties

We evaluated associations between the Conservation Reserve Program (CRP) and Ring-necked Pheasant (Phasianus colchicus) populations by modeling Breeding Bird Survey (BBS) counts of Ring-necked Pheasants during 1987-2005 along 388 routes in nine states. Ring-necked Pheasant counts were analyzed as overdispersed Poisson counts in a Bayesian hierarchical model estimated with Markov-chain Monte Carlo methods. This approach allowed for simultaneous estimation of the relationships between BBS counts and various habitat types, including CRP habitat types, for multiple regions and across the entire study area. The predictor variables included a time trend and percentages of major National Land Cover Dataset 1992 and CRP habitat types within a 1,000-m buffer around each route, along with other patch metrics. The deviance information criterion was used as a guide to help identify the most parsimonious model. We estimated that, on average, there was a positive association of Ring-necked Pheasant counts with the amount of CRP herbaceous vegetation within a 1,000-m buffer around a route. The analysis can be repeated periodically to model changes in Ring-necked Pheasant populations associated with new CRP enrollments and expiration of existing CRP contracts on a large scale. Our methodology can also be extended to other species and to other states and regions. Received 4 January 2007, accepted 5 August 200Z Key words: Breeding Bird Survey, Conservation Reserve Program, hierarchical model, Markov-chain Monte Carlo, Phasianus colchicus, Poisson regression, Ring-necked Pheasant. Evaluamos las asociaciones entre el Programa de Conservacion de Reservas (PCR) y las poblaciones de Phasianus colchicus mediante modelos utilizando los conteos de P. colchicus realizados por el Muestreo de Aves Reproductivas (BBS, por sus siglas en ingles) entre 1987 y 2005 a lo largo de 388 rutas en nueve estados. Los conteos de P. colchicus fueron analizados como conteos de Poisson con sobredispersion en un modelo jerarquico Bayesiano estimado con metodos de Monte Carlo y cadenas de Markov. Este enfoque permitio la estimacion simultanea de la relacion entre los conteos del BBS y varios tipos de habitat, incluyendo los tipos de habitat del PCR, para multiples regiones y a traves de toda el area de estudio. Las variables de prediccion incluyeron una tendencia temporal y los porcentajes de los principales tipos de la Base de Datos de Cobertura Terrestre Nacional de 1992 y los tipos de habitat del PCR dentro de un area de amortiguamiento de 1000 m alrededor de cada ruta, junto con otras medidas de los parches. El criterio de informacion de desvio fue usado como una guia para ayudar a identificar el modelo mas parsimonioso. Estimamos que, en promedio, hubo una asociacion positiva entre los conteos de P. colchicus y la cantidad de vegetacion herbacea del PCR dentro de un area de amortiguamiento de 1000 m alrededor de una ruta. El analisis pude ser repetido periodicamente para modelar cambios en las poblaciones de P. colchicus asociados a la incorporacion de nuevos PCR y la expiracion de contratos existentes de PCR a gran escala. Nuestra metodologia puede tambien ser extendida a otras especies y a otros estados y regiones.

Understanding how complex food webs assemble through time is fundamental both for ecological theory and for the development of sustainable strategies of ecosystem conservation and restoration. The build-up of complexity [...]

The articles in this special feature challenge the presumption that scholars can make simple, predictive models of social-ecological systems (SESs) and deduce universal solutions, panaceas, to problems of overuse or destruction of resources. Moving beyond panaceas to develop cumulative capacities to diagnose the problems and potentialities of linked SESs requires serious study of complex, multivariable, nonlinear, cross-scale, and changing systems. Many variables have been identified by researchers as affecting the patterns of interactions and outcomes observed in empirical studies of SESs. A step toward developing a diagnostic method is taken by organizing these variables in a nested, multitier framework. The framework enables scholars to organize analyses of how attributes of (i) a resource system (e.g., fishery, lake, grazing area), (ii) the resource units generated by that system (e.g., fish, water, fodder), (iii) the users of that system, and (iv) the governance system jointly affect and are indirectly affected by interactions and resulting outcomes achieved at a particular time and place. The framework also enables us to organize how these attributes may affect and be affected by larger socioeconomic, political, and ecological settings in which they are embedded, as well as smaller ones. The framework is intended to be a step toward building a strong interdisciplinary science of complex, multilevel systems that will enable future diagnosticians to match governance arrangements to specific problems embedded in a social-ecological context. commons | complexity | governance | interdisciplinary research | sustainability science

Most studies examining continental-to-global patterns of species richness rely on the overlaying of extent-of-occurrence range maps. Because a species does not occur at all locations within its geographic range, range-map-derived data represent actual distributional patterns only at some relatively coarse and undefined resolution. With the increasing availability of high-resolution climate and land-cover data, broad-scale studies are increasingly likely to estimate richness at high resolutions. Because of the scale dependence of most ecological phenomena, a significant mismatch between the presumed and actual scale of ecological data may arise. This may affect conclusions regarding basic drivers of diversity and may lead to errors in the identification of diversity hotspots. Here, we examine avian range maps of 834 bird species in conjunction with geographically extensive survey data sets on two continents to determine the spatial resolutions at which range-map data actually characterize species occurrences and patterns of species richness. At resolutions less than 2[degrees] ([approximately equal to] 200 km), range maps overestimate the area of occupancy of individual species and mischaracterize spatial patterns of species richness, resulting in up to two-thirds of biodiversity hotspots being misidentified. The scale dependence of range-map accuracy poses clear limitations on broad-scale ecological analyses and conservation assessments. We suggest that range-map data contain less information than is generally assumed and provide guidance about the appropriate scale of their use. biodiversity | birds | geographic range | range occupancy | species richness pattern

Lessons in conservation are often seen as resulting from cycles of overexploitation and subsequent depletion of resources, followed by catastrophic consequences of shortage and starvation, and finally, development of various strategies, including privatization of the commons, to conserve remaining resource stocks. While such scenarios have undoubtedly occurred on many occasions, we suggest that they are not the only means by which people develop conservation practices and concepts. There are other pathways leading to ecological understanding and conservation, which act at a range of scales and levels of complexity. These include: lessons from the past and from other places, perpetuated and strengthened through oral history and discourse; lessons from animals, learned through observation of migration and population cycles, predator effects, and social dynamics; monitoring resources and human effects on resources (positive and negative), building on experiences and expectations; observing changes in ecosystem cycles and natural disturbance events; trial and error experimentation and incremental modification of habitats and populations. Humans, we believe, are capable of building a sophisticated conservation ethic that transcends individual species and resources. A combination of conservation knowledge, practices, and beliefs can lead to increasingly greater sophistication of ecological understanding and the continued encoding of such knowledge in social institutions and worldview. Key words Traditional ecological knowledge * conservation * indigenous peoples * ethnoecology.

There are two broadly conceptualized ways in which conservation knowledge may evolve: the depletion crisis model and the ecological understanding model. The first one argues that developing conservation thought and practice depends on learning that resources are depletable. Such learning typically follows a resource crisis. The second mechanism emphasizes the development of conservation practices following the incremental elaboration of environmental knowledge by a group of people. These mechanisms may work together. Following a perturbation, a society can self-organize, learn and adapt. The self-organizing process, facilitated by knowledge development and learning, has the potential to increase the resilience (capability to absorb disturbance and reorganize while undergoing change) of resource use systems. Hence, conservation knowledge can develop through a combination of long-term ecological understanding and learning from crises and mistakes. It has survival value, as it increases the resilience of integrated social-ecological systems to deal with change in ways that continue to sustain both peoples and their environments. KEY WORDS: resource management; conservation; indigenous knowledge; traditional ecological knowledge; resilience; adaptive learning; common property; institutions.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jenvman.2005.07.008 Byline: Kent Donald Messer Abstract: Economic theory asserts that to achieve maximum conservation benefits land acquisition needs to be cost effective. Yet the most common planning technique used by land conservation organizations is 'benefit-targeting' that focuses only on acquiring parcels with the highest benefits and ignores costs. Unlike most of the literature which focuses on covering problems, this research applies optimization techniques to achieve maximum aggregate conservation benefits for an ongoing land acquisition effort in the Catoctin Mountain Region in central Maryland. For this case study, optimization yields additional conservation benefits worth an estimated $3.1-$3.9 million or achieves the same level of conservation benefits but at a cost savings ranging from $0.9 to $3.5 million, depending on the initial budget size. Finally, the highest efficiencies are achieved in low budget scenarios, like those most prevalent in conservation efforts. Author Affiliation: Department of Applied Economics and Management, Cornell University, 454 Warren Hall, Ithaca, NY 14850, USA Article History: Received 13 December 2004; Revised 28 May 2005; Accepted 26 July 2005

In Zimbabwe, many whites have affiliated themselves with the land rather than with surrounding societies. Theories of settler culture--which emphasize ethnic conflict--often overlook this environmentalist form of identity. As conservationists, white, large-scale farmers sought to belong to the landscape, and they modified it in ways that facilitated that sense of belonging. On the semiarid highlands, they manipulated the most manipulable of environmental variables: water. In the 1990s, their new landscape of darns and reservoirs provided habitat for wildlife and irrigation for tobacco. Whites justified their land ownership on grounds of both conservation and development--a considerable rhetorical feat. Engineering, then, fostered an unstable, ephemeral feeling of entitlement and belonging. [Africa, colonialism, identity, land, postcolonialism, settler society, race]

An open-economy model, which investigates whether the resource conversion is determined by a self interested government that is susceptible to the influences of the political contributions it receives from the profit-maximizing economic agent responsible for land conversion, is presented.

Riparian zones are habitats of critical conservation concern worldwide, as they are known to filter agricultural contaminants, buffer landscapes against erosion, and provide habitat for high numbers of species. Here we test the generality of the notion that riparian habitats harbor more species than adjacent upland habitats. Using previously published data collected from seven continents and including taxa ranging from Antarctic soil invertebrates to tropical rain forest lianas and primates, we show that riparian habitats do not harbor higher numbers of species, but rather support significantly different species pools altogether. In this way, riparian habitats increase regional ([gamma]-) richness across the globe by >50%, on average. Thus conservation planners can easily increase the number of species protected in a regional portfolio by simply including a river within terrestrial biodiversity reserves. Our analysis also suggests numerous possible improvements for future studies of species richness gradients across riparian and upland habitats. First, Key words: conservation planning; regional diversity; riparian cone; river; similarity; species diversity; species richness; turnover; upland; watershed reserves.

The karst landscapes of Trinidad and Tobago, although restricted in area, present a previously undocumented array of tropical karst landforms, including karren, caves, springs, valley systems, and a range of dolines or sinkholes, including an area of polygonal cockpit karst. The karstlands are located primarily in the Northern and Central Ranges of Trinidad and in the southwestern portion of Tobago, and they have developed on carbonate rocks ranging in age from Jurassic to Quaternary. Associated with them is a range of vegetation types and faunal communities, many of which have been much altered by human land management, including forestry and agriculture. Quarrying has destroyed much of the karst in the western part of Trinidad, and urban development and tourism have taken their toll too, especially in the Lowlands of western Tobago. Little of the karst is incorporated within existing protected areas. KEY WORDS: Trinidad, Tobago, karst, geomorphology, land use, conservation

If a population has multiple positive stable equilibria, this information can be useful in natural-resource management. We describe a test for the presence of multiple, potentially stable equilibria in a single population. The test is based on the idea of critical smoothing. Critical smoothing was originally proposed for testing for multiple modes in a probability density function. The test is illustrated using data for the spruce budworm and the snowshoe hare. Key words: bandwidth of a kernel estimator; bootstrap procedures for time series; critical-smoothing test; kernel estimation; multiple equilibria, test; snowshoe hare; spruce budworm.

CHATTERTON P. (2002) 'Be realistic: demand the impossible'. Moving towards 'strong' sustainable development in an old industrial region?, Reg. Studies 36, 552-561. The term sustainable development provides useful guidance on how economic development can be reconciled with protecting the natural environment and meeting social objectives. However, this rather tricky term is open to a number of interpretations ranging from strong/ecological to weak/technocratic. In the context of an old industrial region, evidence of movement towards strong sustainable development in four areas is discussed: radicalising democracy; promoting the local social economy; meeting basic needs; and encouraging biodiversity. The article explores why, in the light of sustained evidence of multiple social and environmental crises, these messages of strong, ecological sustainable development continue to be ignored and marginalized in formulating policy at the regional level. Ecology Radical democracy Sustainable development Regional policy

Outbreeding depression may be in effect on a very local scale within populations of the rare endemic species Anchusa crispa Viv., and important implications for rare plant conservation exist. The species is endemic to a Mediterranean island and has no spatial or temporal floral mechanism that would be helpful to outcrossing. Populatinos are completely homozygous and fixed for single, sometimes different, alleles at several loci.

The role of genetic background in success of reintroduced Peregrine Falcons (Falco peregrinus) was studied in the midwestern US and in Canada. It appears that the adaptability of the species was adequate to override genetic differences of subspecies. Five of seven subspecies released after extirpation of the original birds by chlorinated hydrocarbons contributed to the new breeding population.

The umbrella species concept and the selection of large patches of natural vegetation are common but relatively untested approaches for prioritizing conservation areas and the former has been tested in Minnesota. Conservation-priority areas in a fragmented landscape, Agassiz Beach Ridges, were identified based on selection of large patches of natural vegetation and the umbrella species concept to look at the habitat needs of the Greater Prairie Chicken, Tympanuchus cupido pinnatus.

The scientific foundation of habitat conservation plans has been assessed quantitatively for 43 plans. Secondarily the extent of involvement by, and influence of, independent scientists within the process was evaluated. Available scientific information categories was fairly well used in a majority of categories, overall.

Roadside prairie vegetation restoration in Iowa and its conservation value to butterfly communities are discussed. The butterfly populations were benefited. The roadsides have the potential to serve as corridors.

Moths and their countryside biogeography in a fragmented landscape are discussed relative to biodiversity in native and agricultural habitats in Costa Rica. No significant difference was seen in moth species richness or abundance in agricultural habitats, but agricultural areas within 1 km of a forest fragment have significantly higher richness and abundance vs sites 3.5+ km from the fragment.

Ecological consequences of recent climate change are discussed in this review article, which states that the Earth's climate has warmed by 0.5 degree centigrade in the most recent century and that effects of a changing climate on ecological systems can be detected. As the climate changes more and interacts with such stressors as habitat fragmentation, more threats will appear. Studies show the need for current conservation efforts to take climate change into account.

Genetic variation for morphological and allozyme variation in relation to population size in Clarkia dudleyana, an endemic annual. Maintenance of genetic variation within populations is thought to allow species to respond to evolutionary challenges. Study shows that levels of allozyme variability do not predict levels of genetic variation for morphological trains in C. dudleyana.

The implications of inherent rarity for community restoration are explored. The assumption that if a habitat is created then colonist comes, is applicable to some species only. It is expected that passive connectivity is insufficient to ensure colonization of restored buffers, corridors or stepping-stone habitats.

The Maine lobster industry is used to study agreements to conserve resources. The agreement in Maine was successful in establishing a managed annual catch that sustains resource levels.