How do habitat amount and habitat fragmentation drive time-delayed responses of biodiversity to land-use change?

ASUNCIÓN SEMPER-PASCUAL ; COLE BURTON; MATTHIAS BAUMANN; JULIETA DECARRE; GREGORIO GAVIER-PIZARRO; BIBIANA GÓMEZ-VALENCIA; LEANDRO MACCHI; MATÍAS E. MASTRANGELO; FLORIAN PÖTZSCHNER; PATRICIA V. ZELAYA; TOBIAS KUEMMERLE

PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON. SERIES B: BIOLOGICAL SCIENCES.

ROYAL SOC

Año: 2021 vol. 288 p. 1 - 10

0962-8452

Land-use change is a root cause of the extinction crisis, but links betweenhabitat change and biodiversity loss are not fully understood. While there isevidence that habitat loss is an important extinction driver, the relevanceof habitat fragmentation remains debated. Moreover, while time delays ofbiodiversity responses to habitat transformation are well-documented, timedelayed effects have been ignored in the habitat loss versus fragmentationdebate. Here, using a hierarchical Bayesian multi-species occupancy framework,we systematically tested for time-delayed responses of bird andmammal communities to habitat loss and to habitat fragmentation. We focusedon the Argentine Chaco, where deforestation has been widespread recently.We used an extensive field dataset on birds and mammals, along with atime series of annual woodland maps from 1985 to 2016 covering recent andhistorical habitat transformations. Contemporary habitat amount explainedbird and mammal occupancy better than past habitat amount. However, occupancywas affected more by the past rather than recent fragmentation,indicating a time-delayed response to fragmentation. Considering past landscapepatterns is therefore crucial for understanding current biodiversitypatterns. Not accounting for land-use history ignores the possibility of extinction debt and can thus obscure impacts of fragmentation, potentiallyexplaining contrasting findings of habitat loss versus fragmentation studies.1.