| Итог: | Neotropical freshwater habitats are particularly sensitive to degradation
by human activity. Piscivorous semi-aquatic freshwater megafauna
inhabit both the terrestrial and aquatic mediums and thus may be good
indicators of wetland habitat quality. However, the drivers of their space
use at the terrestrial and aquatic landscape levels are not well
understood. We studied the spatial behavior and habitat use of giant
otters in Madre de Dios, Peru, inhabiting areas with variable levels of
protection. We combined Unmanned Aerial Vehicle (UAV) and satellite
images to develop different terrestrial and water-associated land cover
variables. We tested the influence of these predictors on giant otter
habitat use at multiple spatial scales, comparing used and available
locations. Giant otters favored bank areas with dense forest canopy
cover. In the aquatic medium, giant otters showed positive selection for
open water and fallen logs and avoided floating vegetation. These
findings may be explained by preference for optimal fish habitat to
maximize foraging yield and bank areas that provide more cover from
predators and higher quality denning locations. Variables developed from
UAV images outperformed satellite-derived variables. Despite recent
signs of deforestation in lake banks in unprotected areas, spatial model
predictions indicated that unprotected oxbow lakes did not differ in their
habitat suitability from protected freshwater habitats. Management
implications of our findings include identification of factors driving habitat
suitability to guide policy and decisions regarding protection or
restoration of oxbow lake ecosystems to support giant otter populations.
In addition, we demonstrate that UAVs have value in complementing
satellite-derived images and providing a cost-effective methodology to
assess habitat quality for semi-aquatic species at the land-water
interface.
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