Virtual Corridors for Conservation Management

: Corridors are usually perceived as clearly visible, linear landscape elements embedded in a hostile environment that connect two or more larger blocks of habitat. Animal response to certain aspects of landscape heterogeneity, however, can channel their movements into specific routes that may appear similar to their surroundings. These routes can be described as “virtual corridors” (VCs). Here we contribute to the foundation of the concept of VCs and highlight their implications for conservation management. We used an individual-based model to analyze the formation of VCs in the case of hilltopping in butterflies—where males and virgin females ascend to hilltops and mate. We simulated butterfly movements in two different topographically heterogeneous landscapes. We analyzed the movement patterns with respect to one parameter, the intensity of response to topography. Virtual corridor structure depended on the behavioral parameter, landscape, and location of the source patch. Within a realistic range of the behavioral parameter and in a realistic landscape, VC structures may be complex and require individual-based models for their elucidation. Resumen: Los corredores generalmente son percibidos como elementos lineales del paisaje claramente visibles que estan embebidos en un ambiente hostil y que conectan a dos o mas bloques extensos de habitat. Sin embargo, la respuesta de los animales a ciertos aspectos de la heterogeneidad espacial puede canalizar sus movimientos hacia rutas especificas que pueden ser similares a su entorno. Estas rutas pueden ser descritas como “corredores virtuales” (CV). Aqui contribuimos a la establecer del concepto de CV y resaltamos sus implicaciones para la gestion de la conservacion. Utilizamos un modelo basado en individuos para analizar la formacion de CV en el caso de “hilltopping” en mariposas—las hembras virgenes y los machos ascienden a las cimas de colinas para aparearse. Simulamos los movimientos de mariposas en dos paisajes heterogeneos topograficamente. Analizamos los patrones de movimientos con respecto a un parametro, la intensidad de respuesta a la topografia. La estructura de los corredores virtuales dependio del parametro conductual, el paisaje, y la localizacion del parche de procedencia. En un rango realista del parametro de conducta y en un paisaje realista, la estructura de CV puede ser compleja y requerir de modelos basados en individuos para su dilucidacion.

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