Experiments were conducted at two spatial scales to investigate the effects of terrestrial frogs (Eleutherodactylus coqui) on aerial and litter invertebrates, plant growth and herbivory, and litter decomposition. Results showed that at both scales, frogs reduced aerial invertebrates and leaf herbivory, but had no effect on litter invertebrates. At the smaller scale, frogs increased foliage production rates, measured as the number of new leaves and new leaf area produced, by 80% and decomposition rates by 20%. These results demonstrate that E. coqui may affect ecosystem functions by decreasing prey items and increasing nutrient cycling rates (Beard et al. 2003).
In Hawai‘i where the population is seen to be expanding, there are concerns of ecological as well as anthropogenic affects. The main pathway for spread has been through the nursery trade and there are concerns that there may be a negative effect on the export nursery trade, should shipments be banned for harbouring frogs. E. coqui have spread from horticultural sites where they were first restricted to public land, residential areas and resorts. There are concerns that property value may be affected due to the high biomass of frogs on infested sites (Kraus and Campbell, 2002). The high pitched call of the frog is a disturbance and there are fears this may affect the tourism industry (HEAR, 2004).
Location Specific Impacts:
Hawaii (United States (USA))
Economic/Livelihoods: Results of a study conducted by Kaiser & Burnett (2006) to evaluate the economic impacts of E. coqui frogs in Hawai'i, concludes that that "the presence of the noisy coqui frog in Hawai'i county has begun to lower property values". The authors estimate direct damage to property values at a minimum of US$7.6 million and expected losses in profitability for floriculture and nursery products at US$81,000 in losses per year for the county, if the frog spread across all residential properties. For more details, please follow this link Kaiser & Burnett 2006 .