Biases and information gaps in the study of habitat connectivity in the Carnivora in the Americas

Abstract

1. Habitat connectivity is essential to mitigate the effects of fragmentation by maintaining ecological processes, exchange of individuals, and gene flow among isolated populations. In the last two decades, the importance of habitat connectivity has been highlighted and the number of studies that address this issue has increased. 2. We review and describe the habitat-connectivity studies for the Carnivora in the Americas to identify taxonomic, geographic, and methodological biases, and we examine the number of publications on habitat connectivity and their relationship with country-level parameters. 3. We reviewed habitat-connectivity studies published between 2000 and 2020.We quantified studies by region, country, family, and species. We identified information gaps and analysed each country based on the proportion of land modified by humans, species richness, percentage of carnivoran species that are at risk of extinction, and the percentage of territory that is within Protected Areas. G-tests were performed to verify if the number of published connectivity studies differed based on these variables. 4. There is an increasing trend in the number of studies; however, this increasing is not proportional among countries, among families, or among carnivoran species. We identified that there is a regional bias, since more than 75% of the studies were carried out in North America, in addition, taxonomic bias indicates that the studies focused on large carnivorans. Regarding the methodological bias, the least-cost path was the most used approach. 5. There are fewer studies on habitat connectivity in countries with higher fragmentation rates, higher percentages of species that are at risk of extinction and less percentage of land in Protected Areas. The capability of countries to invest in research, the study focused on large charismatic species and the difficulty to obtaining dispersion data are factors that have influenced in the study of habitat connectivity.