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Understanding individual attitudes and how these predict overt opposition to predator conservation or direct, covert action against predators will help to recover and maintain them. Studies of attitudes toward wild animals rely primarily on samples of individuals at a single time point. We examined longitudinal change in individuals' attitudes toward gray wolves (Canis lupus). In the contiguous United States, amidst persistent controversy and opposition, abundances of gray wolves are at their highest in 60 years. We used mailed surveys to sample 1892 residents of Wisconsin in 2001 or 2004 and then resampled 656 of these individuals who resided in wolf range in 2009. Our study spanned a period of policy shifts and increasing wolf abundance. Over time, the 656 respondents increased agreement with statements reflecting fear of wolves, the belief that wolves compete with hunters for deer (Odocoileus virginianus), and inclination to poach a wolf. Endorsement of lethal control of wolves by the state and public hunting of wolves also increased. Neither the time span over which respondents reported exposure to wolves locally nor self-reported losses of domestic animals to wolves correlated with changes in attitude. We predict future increases in legal and illegal killing of wolves that may reduce their abundance in Wisconsin unless interventions are implemented to improve attitudes and behavior toward wolves. To assess whether interventions change attitudes, longitudinal studies like ours are needed. El entendimiento de las actitudes individuales y la forma en que predicen oposición abierta a la conservación de depredadores o acción directa encubierta contra depredadores ayudará a recuperarlos y mantenerlos. Los estudios de actitudes hacia animales silvestres se basan principalmente en muestreos de individuos en un solo momento. Examinamos el cambio longitudinal en las actitudes de individuos hacia lobos grises (Canis lupus). En Estados Unidos, en medio de controversia y oposición persistentes, las abundancias de lobos grises están en su mayor punto en 60 años. Utilizamos encuestas enviadas por correo para muestrear 1892 residentes de Wisconsin en 2001 o 2004 y posteriormente muestreamos nuevamente a 656 de esos individuos que residían en áreas con lobos en 2009. Nuestro estudio abarcó un período de cambios en las políticas e incremento en la abundancia de lobos. En el tiempo, 656 encuestados incrementaron su acuerdo con afirmaciones que reflejan el temor a lobos, su creencia de que los lobos compiten con cazadores por venados (Odocoileus virginianus) y su inclinación por cazar un lobo furtivamente. También incrementó el respaldo por el control letal de lobos por el estado, así como la cacería pública de lobos. No hubo correlación entre los cambios de actitud con el período de tiempo en el cual los encuestados reportaron exposición local a lobos ni con el reporte de pérdida de animales domésticos causada por lobos. Pronosticamos mayores incrementos en la matanza legal e ilegal de lobos, lo cual puede reducir su abundancia en Wisconsin a menos que se implementen intervenciones para mejorar las actitudes y comportamiento hacia los lobos. Para evaluar si las intervenciones cambian las actitudes, se requieren estudios longitudinales como el nuestro.

Animal-mediated seed dispersal is important for sustaining biological diversity in forest ecosystems, particularly in the tropics. Forest fragmentation, hunting, and selective logging modify forests in myriad ways and their effects on animal-mediated seed dispersal have been examined in many case studies. However, the overall effects of different types of human disturbance on animal-mediated seed dispersal are still unknown. We identified 35 articles that provided 83 comparisons of animal-mediated seed dispersal between disturbed and undisturbed forests; all comparisons except one were conducted in tropical or subtropical ecosystems. We assessed the effects of forest fragmentation, hunting, and selective logging on seed dispersal of fleshy-fruited tree species. We carried out a meta-analysis to test whether forest fragmentation, hunting, and selective logging affected 3 components of animal-mediated seed dispersal: frugivore visitation rate, number of seeds removed, and distance of seed dispersal. Forest fragmentation, hunting, and selective logging did not affect visitation rate and were marginally associated with a reduction in seed-dispersal distance. Hunting and selective logging, but not fragmentation, were associated with a large reduction in the number of seeds removed. Fewer seeds of large-seeded than of small-seeded tree species were removed in hunted or selectively logged forests. A plausible explanation for the consistently negative effects of hunting and selective logging on large-seeded plant species is that large frugivores, as the predominant seed dispersers for large-seeded plant species, are the first animals to be extirpated from hunted or logged forests. The reduction in forest area after fragmentation appeared to have weaker effects on frugivore communities and animal-mediated seed dispersal than hunting and selective logging. The differential effects of hunting and selective logging on large-and small-seeded tree species underpinned case studies that showed disrupted plant-frugivore interactions could trigger a homogenization of seed traits in tree communities in hunted or logged tropical forests. La dispersión de semillas por animales es importante para sustentar la diversidad biológica en ecosistemas forestales, particularmente en los trópicos. La fragmentación de bosques, la cacería y la tala selectiva modifican los bosques de muchas maneras y sus efectos sobre la dispersión de semillas por animales han sido examinados en muchos estudios de caso. Sin embargo, todavía se desconocen los efectos generales de los diferentes tipos de perturbación humana sobre la dispersión de semillas por animales. Identificamos 35 artículos que proporcionaron 83 comparaciones de dispersión de semillas por animales entre bosques perturbados y no perturbados; todas las comparaciones excepto una fueron en bosques tropicales o subtropicales. Evaluamos los efectos de la fragmentación del bosque, la cacería y la tala selectiva sobre la dispersión de especies de árboles con frutos carnosos. Efectuamos un meta análisis para probar si la fragmentación del bosque, la cacería y la tala selectiva afectaban a tres componentes de la dispersión de semillas por animales: tasa de visitación de frugívoros, números de semillas removidas y distancia de dispersión de semillas. La fragmentación del bosque, la cacería y la tala selectiva no afectaron la tasa de visitación y estuvieron marginalmente asociadas con la disminución de la distancia de dispersión. La cacería y la tala selectiva, pero no la fragmentación, se asociaron con una reducción importante en el número de semillas removidas. Menos semillas de especies de árboles con semillas grandes que de semillas pequeñas fueron removidas en bosques con cacería o tala selectiva. Una explicación plausible de los efectos consistentemente negativos de la cacería y la tala selectiva sobre las especies con semillas grandes es que los frugívoros grandes, como los dispersores predominantes de especies de plantas con semillas grandes, son los primeros animales extirpados de bosques con cacería o tala. La reducción de la superficie de bosque después de la fragmentación pareció tener efectos más débiles sobre las comunidades de frugívoros y la dispersión de semillas por animales que la cacería y la tala selectiva. Los efectos diferenciales de la cacería y la tala selectiva sobre especies de árboles con semillas grandes y pequeñas sustentaron estudios de caso que mostraron que la alteración de interacciones planta-frugívoro podría detonar la homogenización de atributos de las semillas en comunidades de árboles en bosques tropicales con cacería o tala.

Long‐term observational studies conducted at large (regional) spatial scales contribute to better understanding of landscape effects on population and evolutionary dynamics, including the conditions that affect long‐term viability of species, but large‐scale studies are expensive and logistically challenging to keep running for a long time. Here, we describe the long‐term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. We explain how the landscape structure has been described, including definition, delimitation, and mapping of the habitat patches; methods of field survey, including the logistics, cost, and reliability of the survey; and data management using the EarthCape biodiversity platform. We describe the long‐term metapopulation dynamics of the Glanville fritillary based on the survey. There has been no long‐term change in the overall size of the metapopulation, but the level of spatial synchrony and hence the amplitude of fluctuations in year‐to‐year metapopulation dynamics have increased over the years, possibly due to increasing frequency of exceptional weather conditions. We discuss the added value of large‐scale and long‐term population studies, but also emphasize the need to integrate more targeted experimental studies in the context of long‐term observational studies. For instance, in the case of the Glanville fritillary project, the long‐term study has produced an opportunity to sample individuals for experiments from local populations with a known demographic history. These studies have demonstrated striking differences in dispersal rate and other life‐history traits of individuals from newly established local populations (the offspring of colonizers) versus individuals from old, established local populations. The long‐term observational study has stimulated the development of metapopulation models and provided an opportunity to test model predictions. This combination of empirical studies and modeling has facilitated the study of key phenomena in spatial dynamics, such as extinction threshold and extinction debt. The long‐term metapopulation study of the Glanville fritillary butterfly (Melitaea cinxia) that has been conducted since 1991 in a large network of 4,000 habitat patches (dry meadows) within a study area of 50 by 70 km in the Åland Islands in Finland. Here, we explain how the landscape structure has been described, including definition, delimitation and mapping of the habitat patches; methods of field survey, including the logistics, cost and reliability of the survey; and data management using the EarthCape biodiversity platform.

Tanzania holds most of the remaining large populations of African lions (Panthera leo) and has extensive areas of leopard habitat (Panthera pardus), and both species are subjected to sizable harvests by sport hunters. As a first step toward establishing sustainable management strategies, we analyzed harvest trends for lions and leopards across Tanzania's 300,000 km 2 of hunting blocks. We summarize lion population trends in protected areas where lion abundance has been directly measured and data on the frequency of lion attacks on humans in high-conflict agricultural areas. We place these findings in context of the rapidly growing human population in rural Tanzania and the concomitant effects of habitat loss, human-wildlife conflict, and cultural practices. Lion harvests declined by 50% across Tanzania between 1996 and 2008, and hunting areas with the highest initial harvests suffered the steepest declines. Although each part of the country is subject to some form of anthropogenic impact from local people, the intensity of trophy hunting was the only significant factor in a statistical analysis of lion harvest trends. Although leopard harvests were more stable, regions outside the Selous Game Reserve with the highest initial leopard harvests again showed the steepest declines. Our quantitative analyses suggest that annual hunting quotas be limited to 0.5 lions and 1.0 leopard/1000 km 2 of hunting area, except hunting blocks in the Selous Game Reserve, where harvests should be limited to 1.0 lion and 3.0 leopards/1000 km 2 . Tanzania mantiene la mayoría de las poblaciones remanentes de leones Africanos (Panthera leo) y tiene extensas áreas de hábitat de leopardo (Panthera pardus), y ambas especies son sujetas a cosechas considerables por cazadores deportivos. Como un primer paso hacia el establecimiento de estrategias de manejo sustentable, analizamos las tendencias de cosecha de leones y leopardos en los 300,000 km 2 de bloques de cacería de Tanzania. Sintetizamos las tendencias poblacionales de leones en áreas protegidas donde la abundancia de leones ha sido medida directamente, así como datos sobre la frecuencia de ataques de leones sobre humanos en áreas agrícolas altamente conflictivas. Ubicamos estos resultados en el contexto de la población humana en rápido crecimiento en Tanzania rural y los efectos concomitantes de la pérdida de hábitat, el conflicto humanos-vida silvestre y las prácticas culturales. Las cosechas de leones han declinado 50% en Tanzania entre 1996 y 2008, y las áreas de cacería con las cosechas iniciales más altas sufrieron las declinaciones más pronunciadas. Aunque cada parte del país está sujeto a alguna forma de impacto antropogénico por habitantes locales, la intensidad de la cacería deportiva fue el único factor significativo en el análisis estadístico de las tendencias poblacionales de leones. Aunque las cosechas de leopardos fueron más estables, regiones fuera de la Reserva de Caza Selous con las cosechas iniciales de leopardos más altas también mostraron las declinaciones más pronunciadas. Nuestros análisis cuantitativos sugieren que las cuotas anuales de cacería se limiten a 0.5 leones y 1.0 leopardo/1000 km 2 de área de cacería, excepto los bloques de cacería en la Reserva de Caza Selous, donde las cosechas deben limitarse a 1.0 león y 3.0 leopardos/1000 km 2 .

Recovery of depleted populations is fundamentally important for conservation biology and sustainable resource harvesting. At low abundance, population growth rate, a primary determinant of population recovery, is generally assumed to be relatively fast because competition is low (i.e., negative density dependence). But population growth can be limited in small populations by an Allee effect. This is particularly relevant for collapsed populations or species that have not recovered despite large reductions in, or elimination of, threats. We investigated how an Allee effect can influence the dynamics of recovery. We used Atlantic cod (Gadus morhua) as the study organism and an empirically quantified Allee effect for the species to parameterize our simulations. We simulated recovery through an individual‐based mechanistic simulation model and then compared recovery among scenarios incorporating an Allee effect, negative density dependence, and an intermediate scenario. Although an Allee effect significantly slowed recovery, such that population increase could be negligible even after 100 years or more, it also made the time required for biomass rebuilding much less predictable. Our finding that an Allee effect greatly increased the uncertainty in recovery time frames provides an empirically based explanation for why the removal of threat does not always result in the recovery of depleted populations or species. El Efecto Allee y la Incertidumbre de la Recuperación de Poblaciones

Assessing anthropogenic effects on biological diversity, identifying drivers of human behavior, and motivating behavioral change are at the core of effective conservation. Yet knowledge of people's behaviors is often limited because the true extent of natural resource exploitation is difficult to ascertain, particularly if it is illegal. To obtain estimates of rule‐breaking behavior, a technique has been developed with which to ask sensitive questions. We used this technique, unmatched‐count technique (UCT), to provide estimates of bushmeat poaching, to determine motivation and seasonal and spatial distribution of poaching, and to characterize poaching households in the Serengeti. We also assessed the potential for survey biases on the basis of respondent perceptions of understanding, anonymity, and discomfort. Eighteen percent of households admitted to being involved in hunting. Illegal bushmeat hunting was more likely in households with seasonal or full‐time employment, lower household size, and longer household residence in the village. The majority of respondents found the UCT questions easy to understand and were comfortable answering them. Our results suggest poaching remains widespread in the Serengeti and current alternative sources of income may not be sufficiently attractive to compete with the opportunities provided by hunting. We demonstrate that the UCT is well suited to investigating noncompliance in conservation because it reduces evasive responses, resulting in more accurate estimates, and is technically simple to apply. We suggest that the UCT could be more widely used, with the trade‐off being the increased complexity of data analyses and requirement for large sample sizes. Una Aproximación Novedosa para Evaluar la Prevalencia y Factores de la Cacería Ilegal en el Serengueti

The emerging world crisis created by declining fish stocks poses a challenge to resource users and managers. The problem is particularly acute in poor nations, such as those in East Africa, where fishing is an important subsistence activity but high fishing intensity and use of destructive gear have resulted in declining catches. In this context developing effective management strategies requires an understanding of how fishers may respond to declines in catch. We examined the readiness of 141 Kenyan fishers to stop fishing under hypothetical scenarios of declines in catch and how socioeconomic conditions influenced their decisions. As expected, the proportion of fishers that would exit the fishery increased with magnitude of decline in catch. Fishers were more likely to say they would stop fishing if they were from households that had a higher material style of life and a greater number of occupations. Variables such as capital investment in the fishery and the proportion of catch sold had weak, nonsignificant relationships. Our finding that fishers from poorer households would be less likely to exit a severely declining fishery is consistent with the literature on poverty traps, which suggests the poor are unable to mobilize the necessary resources to overcome either shocks or chronic low-income situations and consequently may remain in poverty. This finding supports the proposition that wealth generation and employment opportunities directed at the poorest fishers may help reduce fishing effort on overexploited fisheries, but successful interventions such as these will require an understanding of the socioeconomic context in which fishers operate.

Unsustainable fishing simplifies food chains and, as with aquaculture, can result in reliance on a few economically valuable species. This lack of diversity may increase risks of ecological and economic disruptions. Centuries of intense fishing have extirpated most apex predators in the Gulf of Maine (United States and Canada), effectively creating an American lobster (Homarus americanusj monoculture. Over the past 20 years, the economic diversity of marine resources harvested in Maine has declined by almost 70%. Today, over 80% of the value of Maine's fish and seafood landings is from highly abundant lobsters. Inflationcorrected income from lobsters in Maine has steadily increased by nearly 400% since 1985. Fisheries managers, policy makers, and fishers view this as a success. However, such lucrative monocultures increase the social and ecological consequences of future declines in lobsters. In southern New England, disease and stresses related to increases in ocean temperature resulted in more than a 70% decline in lobster abundance, prompting managers to propose closing that fishery. A similar collapse in Maine could fundamentally disrupt the social and economic foundation of its coast. We suggest the current success of Maine's lobster fishery is a gilded trap. Gilded traps are a type of social trap in which collective actions resulting from economically attractive opportunities outweigh concerns over associated social and ecological risks or consequences. Large financial gain creates a strong reinforcing feedback that deepens the trap. Avoiding or escaping gilded traps requires managing for increased biological and economic diversity. This is difficult to do prior to a crisis while financial incentives for maintaining the status quo are large. The long-term challenge is to shift fisheries management away from single species toward integrated social-ecological approaches that diversify local ecosystems, societies, and economies. La pesca no sustentable simplifica las cadenas alimenticias y, como la acuicultura, puede resultar en una dependencia en unas cuantas especies valiosas económicamente. Esta falta de biodiversidad puede incrementar los riesgos de disrupciones ecológicas y económicas. Siglos de pesca intensiva ban extirpado a la mayoría de los depredadores superiores en el Golfo de Maine (E.U.A. y Canadá), creando efectivamente un monocultivo de langosta americana Homarus americanus). Durante los últimos 20 años, la diversidad económica de los recursos marinos cosechados en Maine ha declinado en casi 70%. Ahora, más de 80% del valor de las capturas de peces y mariscos consiste en langostas que son muy abundantes. El ingreso, corregido para la inflación, por langostas ha incrementado consistentemente en casi 400% desde 1985. Manejadores de pesquerías, políticos y Pescadores ven esto como un éxito. Sin embargo, tales monocultivos lucrativos incrementan las consecuencias sociales y ecológicas de declinaciones de langostas en el futuro. En el sur de Nueva Inglaterra, las enfermedades y los estreses relacionados con incrementos en la temperatura del océano resultaron en una declinación de mas de 70% en la abundancia de langostas, lo que obligó a la propuesta del cierre de esa pesquería. Un colapso similar en Maine podría desestabilizar la base social y económica de su costa. Sugerimos que el éxito actual de la pesquería de langosta en Maine es una trampa dorada. Las trampas doradas son un tipo de trampa social en el que las acciones colectivas derivadas de oportunidades atractivas económicamente sobrepasan a las preocupaciones por los riesgos o consecuencias ecológicas y sociales asociadas. El gran ingreso financiero crea una fuerte retroalimentación reforzante que profundiza la trampa. Escapar de o evitar las trampas doradas requiere de manejo para el incremento de la diversidad biológica y ecológica. Esto es difícil de hacer antes de una crisis mientras los incentivos financieros para mantener el status quo son grandes. El reto a largo plazo es cambiar el manejo de pesquerías de una sola especie hacia enfoques sociales-ecológicos integrados que diversifiquen los ecosistemas, las sociedades y las economías locales.

Threats to species from commercial fishing are rarely identified until species have suffered large population declines, by which time remedial actions can have severe economic consequences, such as closure of fisheries. Many of the species most threatened by fishing are caught in multispecies fisheries, which can remain profitable even as populations of some species collapse. Here we show for multispecies fisheries that the biological and socioeconomic conditions that would eventually cause species to be severely depleted or even driven extinct can be identified decades before those species experience high harvest rates or marked population declines. Because fishing effort imposes a common source of mortality on all species in a fishery, the long-term impact of a fishery on a species is predicted by measuring its loss rate relative to that of species that influence the fishery’s maximal effort. We tested our approach on eight Pacific tuna and billfish populations, four of which have been identified recently as in decline and threatened with overfishing. The severe depletion of all four populations could have been predicted in the 1950s, using our approach. Our results demonstrate that species threatened by human harvesting can be identified much earlier, providing time for adjustments in harvesting practices before consequences become severe and fishery closures or other socioeconomically disruptive interventions are required to protect species.

Territorial user rights for fisheries have been advocated as a way to achieve sustainable resource management. However, few researchers have empirically assessed their potential as ancillary marine conservation instruments by comparing them to no-take marine protected areas. In kelp (Lessonia trabeculata) forests of central Chile, we compared species richness, density, and biomass of macroinvertebrates and reef fishes among territorial-user-right areas with low-level and high-level enforcement, no-take marine protected areas, and open-access areas in 42 100-m subtidal transects. We also assessed structural complexity of the kelp forest and substratum composition. Multivariate randomized permutation tests indicated macroinvertebrate and reef fish communities associated with the different access regimes differed significantly. Substratum composition and structural complexity of kelp forest did not differ among access regimes. Univariate analyses showed species richness, biomass, and density of macroinvertebrates and reef fishes were greater in highly enforced territorial-user-right areas and no-take marine protected areas than in open-access areas. Densities of macroinvertebrates and reef fishes of economic importance were not significantly different between highly enforced territorial-user-right and no-take marine protected areas. Densities of economically important macroinvertebrates in areas with low-level enforcement were significantly lower than those in areas with high-level enforcement and no-take marine protected areas but were significantly higher than in areas with open access. Territorial-user-right areas could be important ancillary conservation instruments if they are well enforced. Los derechos de usuario territoriales para pesquerías han sido propugnados como una forma para alcanzar el manejo sustentable de recursos. Sin embargo, pocos investigadores han evaluado su potencial empíricamente como un instrumento accesorio de la conservación marina mediante la comparación con áreas marinas protegidas sin captura. En bosques de algas laminares (Lessonia trabeculata) en el centro de Chile, comparamos la densidad y biomasa de macroinvertebrados y peces arrecifales entre áreas de derechos de uso territoriales con bajos y altos niveles de aplicación de la ley, áreas marinas protegidas sin captura y áreas de acceso abierto en 42 transectos submareales de 100 m. También evaluamos la complejidad estructural y composición del sustrato del bosque de algas laminares. Pruebas multivariadas de permutación aleatorizada indicaron que las comunidades de macroinvertebrados y peces arrecifales asociadas con los diferentes regímenes de acceso difirieron significativamente. La composición del sustrato y la complejidad estructural del bosque de algas laminares no difirieron entre regímenes de acceso. Análisis univariados mostraron que la riqueza de especies, la biomasa y la densidad de macroinvertebrados y peces arrecifales fueron mayores en las áreas de derechos de uso territoriales con altos niveles de aplicación de la ley y en las áreas marinas protegidas sin captura que en las áreas de acceso abierto. Las densidades de macroinvertebrados y peces arrecifales de importancia económica no fueron significativamente diferentes entre áreas de derechos de uso territoriales con altos niveles de aplicación de la ley y áreas marinas protegidas sin captura. Las densidades de macroinvertebrados de importancia económica en áreas con bajo nivel de aplicación de la ley fueron significativamente menores que en las áreas con niveles altos de aplicación de la ley y las áreas marinas protegidas sin captura pero fueron significativamente mayores que en áreas de acceso abierto. Las áreas de derechos de usuario territoriales pudieran ser importantes instrumentos de conservación accesorios si son aplicadas correctamente.