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Abstract Large scale disturbances are known to significantly alter aspects of both species diversity and ecosystem function. In the Caribbean, hurricane events are a significant form of disturbance, the effects of which have been shown to alter food web function, especially in the terrestrial environment. Although hurricanes have been studied from a variety of their effects on ecosystems, there is little research on how these storms affect species along elevational gradients. Within terrestrial habitats, ants form the basis of many food webs, being both numerically dominant and functioning in a variety of roles within the food web. On September 20th, 2017 Hurricane Maria, a category 4 storm, crossed over the island of Puerto Rico, causing significant damage to both human and natural systems. We collected data on ant abundance and composition from 150 samples of leaf litter along a 700 m elevational gradient during June the year of and after the storm event. Ant abundance increased by 400% after the storm with many common ant species seeming to benefit, especially at lower elevations. There were subtle changes in ant richness, with declines generally after the storm, but yet again this response was dependent on elevation. This is one of the first studies to consider how terrestrial insect communities are affected by large hurricane events across elevations, and our results are in contrast to past work showing declines in ant abundance after such storms. Abstract in Spanish is available with online material.
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Influence of a simulated hurricane on aquatic insect recolonization in the phytotelma of Heliconia caribaea (Heliconiacaea)
Abstract Disturbances like hurricanes can affect diversity and community composition, which may in turn affect ecosystem function. We examined how a simulated hurricane disturbance affected insect communities inhabiting the phytotelma (plant‐held waters) ofHeliconia caribaeain the Luquillo Experimental Forest of eastern Puerto Rico, a tropical island that frequently experiences hurricanes. We hypothesized that disturbance would alter diversity and that largerHeliconiawould attract more species following disturbance due to the area‐diversity relationship described by the Theory of Island Biogeography. Individual flower parts (bracts) ofHeliconiainflorescences (racemes) were artificially disturbed via removal of existing insect communities, then after refilling with water, cohorts ofHeliconiawere destructively sampled biweekly for 6 weeks to assess recolonization patterns of α (bract level), β, and γ (summed across bracts; raceme level) diversity over time and across raceme sizes. Although we found no support for our hypothesis about the effect of raceme size on recolonization, our hypothesis regarding recolonization patterns over time was supported; species richness, evenness, and abundance of bracts increased directly after the disturbance and then decreased below pre‐disturbance levels, and community composition at the raceme level changed significantly over time during recolonization. β Diversity was also greater in smaller racemes compared to larger racemes, suggesting high heterogeneity across bracts ofHeliconiaracemes exacerbated by raceme size and age. Overall, our results highlight the importance of scale and appropriate measurements of diversity (particularly α) in experiments aiming to extrapolate conclusions about the ecological impacts of disturbances across different habitats and ecosystems.
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- Award ID(s):
- 1831952
- PAR ID:
- 10441375
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Biotropica
- Volume:
- 55
- Issue:
- 4
- ISSN:
- 0006-3606
- Format(s):
- Medium: X Size: p. 866-876
- Size(s):
- p. 866-876
- Sponsoring Org:
- National Science Foundation
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