2017 ESA Annual Meeting (August 6 -- 11)

COS 163-1 - Unraveling landscape use by an ecosystem engineer with high-resolution GPS data: Towards better management of agricultural lands

Thursday, August 10, 2017: 1:30 PM
C122, Oregon Convention Center
Maria Luisa Jorge1, Jennifer Leigh Bradham2, Julia Oshima3, Alexine Keuroghlian4 and Milton Cezar Ribeiro3, (1)Earth & Environmental Sciences, Vanderbilt University, Nashville, TN, (2)Earth and Environmental Sciences, Vanderbilt University, (3)Ecologia, Universidade Estadual Paulista, Rio Claro, Brazil, (4)WCS-Brazil, Campo Grande, Brazil
Background/Question/Methods

Pockets of native habitat embedded in agricultural lands are becoming pervasive throughout the world, and their importance to mitigate biodiversity loss is increasingly recognized. Yet, for effectiveness of their function, it is crucial to understand how native species use these lands. White-lipped peccaries (WLP) are social forest ungulates that provide important services to their ecosystems, such as seed dispersal, seed and seedling predation, and soil uprooting. Populations of WLP can still be found in some agricultural lands. Nevertheless, it is unclear how they use these new landscapes and how their provision of services might be affected. In this study, we assessed how WLP herds use agricultural landscapes and whether they preferentially select specific landscape features. To address this question, we quantified habitat use by ten white-lipped peccaries from five herds (~two individuals/herd) in a pastureland of Central Brazil. We tracked the individuals with GPS collars, and monitored their positions every 3-6 hours. We then used a 2014, 30x30m resolution, supervised land cover map of the region to quantify percent cover of natural vegetation and fragment size distribution for the entire region and for the areas used by the herds, to understand how the herds use the landscape.

Results/Conclusions

Our studied landscape covers an area of approximately 3,000 km2, with only 33% of the area comprised of native vegetation, most of which in patches smaller than 0.01 km2. Despite the small amount of native habitat, our results show that WLP herds in this fragmented landscape use mostly the remaining forests (in average, 89% of locations/individual were in native forests, ranging from 74 to 96%, N = 10). Furthermore, herds preferentially use the largest patches. Two herds (four animals) had 94-99% of their locations in the two largest patches of the landscape (~500 and 700 km2). Two other herds (four animals) had 98% of their locations in three patches ranging from 8, 22 and 47 km2. Finally, two individuals living in a more fragmented portion of the landscape had more than half of their locations in a few fragments larger than 7 km2 and 40 km2, respectively. Our results indicate that WLP herds occurring in agricultural landscapes continue to use almost exclusively the remaining native habitat and select the largest patches. To ensure that these important ecosystem engineers continue to occur in agricultural lands, it is fundamental that large and well-connected native habitat is still present.