Targeted habitat restoration can reduce extinction rates in fragmented forests

Background

Habitat lost is one of the primary drivers of species extinction. This study examines two highly-fractured ecosystems, the Eastern Arc Mountains of Tanzania and the Atlantic Forest of Brazil, and evaluates the rate at which habitat loss may lead to extinction and thus biodiversity loss. Specifically, the authors use halflife vs. area relationship to determine how long it will take to lose one-half of all tropical bird communities in each habitat. 

Goals & Methods

The goal of the study was to provide quantative data that can contribute to theh assessment of the impact of habitat restoration on the persistence of tropical bird species in biodiversity hotspots. The authors first used continental species–area relation (SAR) to estimate the initial species richness in fragments. They then estimated the increase in species persistence by regenerating a forest connection 1 km in width among the largest and closest fragments at 11 locations.

Conclusions & Takeaways

Newmark et al. found that forest corridors connecting fragments in global biodiversity hotspots could provide high returns on conservation investment. Species extinction after habitat loss is often delayed and the authors' model suggests that re-generating forest between fragments could increase species persistence time by up to 56 fold. The study suggest that corridors are important because coastal species with limited ranges are particularly vulnerable to climate change, in addition to existing habitat loss. The paper concludes that $21-49 million in targeted renegeration (8100 ha in in the Eastern Arc Mountains and 500 ha in the Atlantic forest) would increase species persistence by 2,272 years and 5,102 years in each location respectively.