TESTING THE EFFECT OF PARASITES ON CORAL REEF FISHES RECRUITMENT

Parasites are often cited as environmental factors that may affect the success of reef fish recruitment. However, very few studies, if any, have tested this effect in the field. In this work we explored the interaction between three possible effects, the presence of adult conspecifics, the presence of predators and the presence of a monogenean parasite on adult conspecifics on the recruitment of the damselfish, Dascyllus aruanus. Our results showed that the presence of conspecifics had a strong positive influence on recruitment and that this influence is independent of the number of conspecifics on the coral colony. Moreover, we found that the presence of a predator in a colony reduced the number of recruits to a level as low as when conspecifics are not present on the colony. Finally, the presence of parasites on the conspecifics seemed to have a very limited effect on recruitment, neither attracting nor repelling recruits. This result suggests that probably monogeneans are not able to attract newly recruited fishes in order to infect them and equally that the recruits are unable to detect any threats of the parasites on their conspecifics.