RESUMEN
Most post-construction fatality monitoring (PCFM) studies to date have focused on North America and Europe, and this information has been used to assess the impacts of large-scale wind energy on birds and bats. A comprehensive review of wind-wildlife fatality information is still lacking for Latin America; however, given the current installed capacity and the projected increase of wind energy production across Latin America, it is important to fill in the knowledge gap on impacts to wildlife. To provide a current summary of known impacts to birds and bats in Latin America and to identify gaps on this important information, we compiled, reviewed, and synthesized bird and bat fatality information at wind energy projects in the region. Our literature search resulted in 10 references relevant to the scope of this review, six of which provided number of fatalities by species and the type of PCFM search being conducted, meeting our criteria for inclusion in fatality summaries. From this pool, we found that Passerines composed the majority of bird fatalities, with no Threatened bird species reported. The bat family Molossidae composed the majority of bat fatalities, with one Threatened bat species reported. Our review of all studies and focused assessment of only those studies with fatality summaries indicated differences in the amount of information and level of detail related to bird and bat fatalities at wind energy projects in Latin America. Due to the taxon-specific nature of collision risk with wind turbines for birds and bats, it is difficult to make a general impact assessment of wind energy development on birds and bats in Latin America, especially given the limited information available. However, this summary can be used as a starting point to inform conservation efforts aiming at avoiding, minimizing, and mitigating impacts of wind energy development on birds and bats and future, standardized results would enhance our ability to do so.
RESUMEN
BACKGROUND: Rhipicephalus (Boophilus) annulatus and Rhipicephalus (Boophilus) microplus (southern cattle fever tick; SCFT), collectively known as cattle-fever ticks (CFTs), are vectors of protozoal parasites (Babesia bigemina and Babesia bovis) that cause bovine babesiosis (also known as cattle fever). One traditional strategy for CFT eradication involves the implementation of a "pasture vacation," which involves removing cattle (Bos taurus) from an infested pasture for an extended period of time. However, vacated pastures are often inhabited by wildlife hosts, such as white-tailed deer (WTD; Odocoileus virginianus), which can serve as alternate hosts for questing CFTs. We hypothesized that the distribution of host-seeking larvae among habitat types post-pasture vacation would reflect habitat use patterns of WTD, and in turn, affect the subsequent rate of pasture infestation by CFT. METHODS: We adapted a spatially explicit, individual-based model to simulate interactions among SCFT, cattle, and WTD as a tool to investigate the potential effects of WTD habitat use preferences on the efficacy of a pasture vacation. We parameterized the model to represent conditions typical of rangelands in south Texas, USA, simulated a 1-year pasture vacation under different assumptions regarding WTD habitat use preferences, and summarized effects on efficacy through (1) time post-vacation to reach 100% of pre-vacation densities of host-seeking larvae, and (2) the ecological conditions that resulted in the lowest host-seeking larval densities following pasture vacation. RESULTS: Larval densities at the landscape scale varied seasonally in a similar manner over the entire simulation period, regardless of WTD habitat use preferences. Following the removal of cattle, larval densities declined sharply to < 100 larvae/ha. Following the return of cattle, larval densities increased to > 60% of pre-vacation densities ≈ 21 weeks post-vacation, and reached pre-vacation levels in less than a year. Trends in larval densities in different habitat types paralleled those at the landscape scale over the entire simulation period, but differed quantitatively from one another during the pasture vacation. Relative larval densities (highest to lowest) shifted from (1) wood/shrub, (2) grass, (3) mixed-brush during the pre-vacation period to (1) mixed-brush, (2) wood/shrub, (3) grass or (1) wood/shrub, (2) mixed-brush, (3) grass during the post-vacation period, depending on WTD habitat use preferences. CONCLUSIONS: By monitoring WTD-driven shifts in distributions of SCFT host-seeking larvae among habitat types during simulated pasture vacation experiments, we were able to identify potential SCFT refugia from which recrudescence of infestations could originate. Such information could inform timely applications of acaricides to specific refugia habitats immediately prior to the termination of pasture vacations.
