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Published on: February 11, 2020
Remote forest refugia for Fijian wildlife
David Olson1, Linda Farley, Waisea Naisilisili
1Wildlife Conservation Society-South Pacific, 11 Ma'afu Street, Suva, Fiji. dolson@wcs.org
Summary
Remote Pacific island forests offer refuge for native species threatened by invasive rats and mongooses. Protecting large forest blocks is key to conserving island endemics from predation.
Area of Science:
- Ecology
- Conservation Biology
- Island Biogeography
Background:
- Non-native rats and mongooses pose significant threats to native species on Pacific islands.
- Predation pressure from invasive species can impact biodiversity in island ecosystems.
Purpose of the Study:
- To compare visitation rates of rats and mongooses at bait stations.
- To measure leaf-litter invertebrate biomass.
- To assess relative predation pressure in forest areas at varying distances from the forest edge in Fiji.
Main Methods:
- Bait stations were used to monitor rat and mongoose activity.
- Leaf-litter invertebrate biomass was quantified.
- Data were collected from forest areas at different distances from the forest edge.
Main Results:
- Fewer baits were encountered by rats and mongooses in forest areas over 5 km from the forest edge compared to areas nearer agricultural/urban habitats.
- Higher biomass of leaf-litter invertebrates was found in remote forest areas, suggesting a refuge effect.
- Logging roads were identified as potential dispersal routes for rats into natural forests.
Conclusions:
- Remote forest areas serve as crucial refuges for island species vulnerable to invasive predators.
- Conservation strategies should prioritize the protection of large, intact natural forest blocks on Pacific islands.
- Minimizing habitat fragmentation, such as through logging roads, is essential to maintain these refuges.
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