Family Planning: Does Variation in Reproductive Strategies Affect Vulnerability to Extinction in the Greater Spear-Nosed BatPhyllostomus Hastatus?

Abstract

Different reproductive strategies among populations might affect population growth rates, and a population's vulnerability to threats. Population viability analysis may help guide population management and the identification of populations more prone to decline, allowing a preventive approach to avoid population declines and extinctions. The objective of the present study was to evaluate if differences in reproductive strategy translate into differential intrinsic vulnerability among different populations of Phyllostomus hastatus. We used the software VORTEX to model the dynamics and viability of P. hastatus populations under different reproductive scenarios. We modeled a total of 12 scenarios evaluating variations in reproductive characteristics of the species (monoestry vs polyestry, harem size, and infant mortality rate). Phyllostomus hastatus populations were viable under most scenarios, except with scenarios incorporating monoestry and high pup mortality. Our results demonstrate that both reproductive strategies (monoestry and polyestry) found in P. hastatus result in viable and stable populations under natural conditions. However, polyestrous populations have higher growth rates, making them more resilient to natural and/or anthropogenic disturbances. A significant portion of the more resilient populations in South America overlap the Amazon Forest, a continuous and preserved habitat under low human pressure, which bodes well for the long-term persistence of these populations. On the other hand, the populations of the species that evolved the monoestrous reproductive strategy are located in Mesoamerica, a Biodiversity Hotspot that is under severe human impacts, particularly from habitat loss. Conservation biologists and managers must take into account intra-specific demographic differences of species when planning for their long-term persistence.