Publications des scientifiques de l'IRD

Dumas Pascal, Moutardier G., Ham J., Kaku R., Gereva S., Lefevre Jérôme, Adjeroud Mehdi. (2016). Timing within the reproduction cycle modulates the efficiency of village-based crown-of-thorns starfish removal. Biological Conservation, 204 (B), p. 237-246. ISSN 0006-3207.

Titre du document
Timing within the reproduction cycle modulates the efficiency of village-based crown-of-thorns starfish removal
Année de publication
2016
Type de document
Article référencé dans le Web of Science WOS:000390968900013
Auteurs
Dumas Pascal, Moutardier G., Ham J., Kaku R., Gereva S., Lefevre Jérôme, Adjeroud Mehdi
Source
Biological Conservation, 2016, 204 (B), p. 237-246 ISSN 0006-3207
In Pacific countries, outbreaks of the crown-of-thorns starfish Acanthaster planci (COTS) raise increasing conservation concerns in areas where people heavily depend upon coral reefs for their livelihoods. Small-scale cleanups are often used in an attempt to regulate COTS densities, but their efficiency is challenged by knowledge gaps and the difficulty for the communities to frame their decisions in an ecological perspective. Here, we investigated COTS reproductive seasonality and its potential impact on removals. The spawning period of COTS was documented in two islands of the Vanuatu archipelago using the gonado-somatic index (GSI). Peak spawning occurred one month after the 28 degrees C threshold was exceeded and was delayed by 2-3 weeks with increasing latitude, theoretically allowing cleanups to be framed within the biological cycle. We demonstrated that subsampiing of two/three arms per starfish provide GSI errors <1, a cost-effective strategy to document local spawning patterns. This approach was used during a major cleanup effort that took place during the spawning season, where fishermen removed COTS from a 3.8 km fringing reef. The density drastically dropped from 518.8 to 66.7 ind.ha(-1) after participants extirpated >4 tons (13,000 starfish). At the end of the removals, GSI was reduced by half when compared to control areas, suggesting that traditional practices may under certain conditions trigger synchronized spawning. More effectively controlling COTS outbreaks will require teaching good ecological practices to avoid potential side-effects, a challenge in countries where a lack of knowledge on COTS does not really foster environmental concerns among local communities.
Plan de classement
Limnologie biologique / Océanographie biologique [034] ; Ecologie, systèmes aquatiques [036]
Description Géographique
PACIFIQUE ; VANUATU
Localisation
Fonds IRD [F B010068825]
Identifiant IRD
fdi:010068825
Contact