Anticipating anthropogenic threats in acquiring new protected areas.

Biodiversity continues to decline despite protected area expansion and global conservation commitments. Biodiversity losses occur in existing protected areas, yet common methods used to select protected areas ignore postimplementation threats that reduce effectiveness. We developed a conservation planning framework that considers the ongoing anthropogenic threats within protected areas when selecting sites and the value of planning for costly threat-mitigating activities (i.e., enforcement) at the time of siting decisions. We applied the framework to a set of landscapes that contained the range of possible correlations between species richness and threat. Accounting for threats and implementing enforcement activities increased benefits from protected areas without increasing budgets. Threat information was valuable in conserving more species per spending level even without enforcement, especially on landscapes with randomly distributed threats. Benefits from including threat information and enforcement were greatest when human threats peaked in areas of high species richness and were lowest where human threats were negatively associated with species richness. Because acquiring information on threats and using threat-mitigating activities are costly, our findings can guide decision-makers regarding the settings in which to pursue these planning steps.

Anticipación de las amenazas antropogénicas durante la adquisición de áreas protegidas nuevas Resumen La biodiversidad sigue declinando a pesar de la expansión de áreas protegidas y los compromisos mundiales con la conservación. La pérdida de la biodiversidad ocurre en las áreas protegidas existentes, y todavía los métodos comunes usados para seleccionar las áreas protegidas ignoran las amenazas posteriores a la implementación, las cuales reducen la efectividad. Desarrollamos un marco de planeación de la conservación que considera las amenazas antropogénicas actuales dentro de las áreas protegidas durante la selección de sitios y el valor de la planeación de actividades mitigantes costosas, como la aplicación, al momento de decidir. Aplicamos nuestro marco a un conjunto de paisajes que comprende el rango de correlaciones posibles entre las amenazas y la riqueza de especies. Si consideramos las amenazas y la implementación de actividades de aplicación, los beneficios de las áreas protegidas incrementan sin incrementar el presupuesto. La información sobre las amenazas fue importante para la conservación de especies por nivel de gasto incluso sin la aplicación, especialmente en paisajes con amenazas distribuidas de forma azarosa. Los beneficios de incluir la información sobre las amenazas y la aplicación fueron mayores cuando las amenazas humanas llegaron a su tope en áreas con gran riqueza de especies y alcanzaron su punto más bajo cuando las amenazas humanas estaban asociadas negativamente con la riqueza de especies. Ya que es costoso adquirir información sobre las amenazas y mitigar las amenazas con actividades, nuestros descubrimientos pueden informar a los tomadores de decisiones con respecto al entorno para seguir los pasos de la planeación.

Molecular detection of reptile-associated Borrelia in Boa constrictor (Squamata: Boidae) from Veracruz, Mexico.

The reptile-associated Borrelia represent a monophyletic group of bacteria transmitted by several species of hard ticks, which has been reported to only infect amphibians and reptiles in Eurasia and Middle East, however, this bacterial group has not been studied in North America. The aim of this study was to assess the presence of Borrelia spirochetes in blood samples of native reptiles of Mexico. Blood samples were directly obtained from individuals, DNA extractions were performed using Chelex-100. The Borrelia detection was performed by conventional PCR. From 102 reptiles tested, only five individuals of Boa constrictor were positive for the presence of DNA of the reptile-associated Borrelia group. Supported by phylogenetic analysis, this study presents the first record of these spirochetes group in Mexico, and initial evidence of B. constrictor as a host of this group.

Environmental heterogeneity explains coarse-scale ß-diversity of terrestrial vertebrates in Mexico.

We explored the hypothesis that high ß-diversity of terrestrial vertebrates of Mexico is associated with a high environmental heterogeneity (HEH) and identify the drivers of ß-diversity at different spatial scales. We used distribution range maps of 2,513 species of amphibians, reptiles, mammals, and birds occurring in Mexico. We estimated ß-diversity for each taxon at four spatial scales (grid cells of 2°, 1°, 0.5° and 0.25°) using the multiplicative formula of Whittaker ßw. For each spatial scale, we derived 10 variables of environmental heterogeneity among cells based on raw data of temperature, precipitation, elevation, vegetation and soil. We applied conditional autoregressive models (CAR) to identify the drivers of ß-diversity for each taxon at each spatial scale. CARs increased in explanatory power from fine-to-coarse spatial scales in amphibians, reptiles and mammals. The heterogeneity in precipitation including both, coefficient of variation (CV) and range of values (ROV), resulted in the most important drivers of ß-diversity of amphibians; the heterogeneity in temperature (CV) and elevation (ROV) were the most important drivers of ß-diversity for reptiles; the heterogeneity in temperature (ROV) resulted in the most important driver in ß-diversity for mammals. For birds, CARs resulted significant at fine scales (grid cells of 0.5° and 0.25°), and the precipitation (ROV and CV), temperature (ROV), and vegetation (H) and soil (H) were heterogeneity variables retained in the model. We found support for the hypothesis of environmental heterogeneity (HEH) for terrestrial vertebrates at coarse scales (grid cell of 2°). Different variables of heterogeneity, mainly abiotic, were significant for each taxon, reflecting physiological differences among terrestrial vertebrate groups. Our study revealed the importance of mountain areas in the geographic patterns of ß-diversity of terrestrial vertebrates in Mexico. At a coarse scale, specific variables of heterogeneity can be used as a proxy of ß-diversity for amphibians and reptiles.