Mosquito Biodiversity Patterns Around Urban Environments in South-Central Okinawa Island, Japan

Abstract

ABSTRACT. Okinawa is the largest, most urbanized, and densely populated island in the Ryukyus Archipelago, where mosquito species diversity has been thoroughly studied. However, the south-central Okinawa mosquito fauna has been relatively poorly studied. Here, we present results from a mosquito faunal survey in urban environments of Nishihara city, south-central Okinawa. Mosquitoes were sampled biweekly, from April 2007 to March 2008, at 3 different environments: a forest preserve, an animal farm, and a water reservoir. We employed 4 mosquito collection methods: 1) oviposition traps; 2) light traps; 3) sweep nets; and 4) larval surveys of tree holes, leaf axils, and artificial water containers. We collected a total of 568 adults and 10,270 larvae belonging to 6 genera and 13 species, including 6 species of medical importance: Aedes albopictus, Armigeres subalbatus, Anopheles Hyrcanus group, Culex bitaeniorhynchus, Cx. quinquefasciatus, and Cx. tritaeniorhynchus. Mosquito species composition was similar to data from previous studies in Okinawa Island. The flattening of the species accumulation curve suggests that our diversity sampling was exhaustive with light and oviposition traps, as well as the coincidence between the species richness we found in the field and estimates from the Chao2 index, a theoretical estimator of species richness based on species abundance. This study highlights the importance of combining several sampling techniques to properly characterize regional mosquito fauna and to monitor changes in the presence of mosquito species.

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“…Thus, probably the species richness estimators would agree with null models, because first null models revealed the presence of many species repeated in many of sampled sites, and the species richness estimators would indicate that the species number would not vary. These results would agree with the descriptions about Chao 1 and Chao2 index that is a robust estimator (Cannon et al, 1998;Martinez-Aquino et al, 2011;Hoshi et al, 2014).…”

Diversity and abundance of mosquitoes (Diptera:Culicidae) in an urban park: Larval habitats and temporal variation

“…Because these areas are designated for human recreation and serve as shelter and refuge for populations of many species of native fauna, migratory or introduced, urban parks are of great interest for ecological studies and studies of the relationship between vertebrate hosts and vectors.They therefore contribute to anunderstanding of how changes in biodiversity caused by urbanization can affect communities in natural fragments and increase the risk of pathogen transmission (Calderón-Arguedas et al, 2009;Chaves et al, 2011;Medeiros-Sousa et al, 2013;Hoshi et al, 2014a).…”

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