Mossler, M.V.

Brood location preference and paternal care behavior by sergeant majors (Abudefduf saxatilis)

Sergeant majors (Abudefduf saxatilis) engage in male-dominated reproduction: males establish territories, females are courted, mate with the male and then depart – leaving protection of the eggs to the male. A. saxatilis prefer smooth, artificial substrate for egg laying; in Bonaire, Dutch Caribbean, they tend to mate on large, concrete mooring blocks which have surfaces of varying degrees of exposure to the water column. Preferred nesting locations were expected to be those offering the least exposure, as broods would be shielded from predators and guarding males would expend minimal energy. The number of threats, chases and feeds in a 5 min interval were recorded as an indicator of energy expenditure and consumption. The length of the fish and size of corresponding egg brood were measured as indicators of mating potential. The number of threats, chases and feeds did not differ significantly between degrees of exposure, but threats and chases differed between sites, being greatest at the site closest to the reef, possibly indicating that exposure does not play a role in energy expenditure and therefore may not affect preferred mating locations. However, larger fish and larger broods were observed on the most protected sides of the mooring blocks offering some support to the notion that A. saxatilis prefer to nest in more protected locations. An increase in the number of artificial structures could lead to an A. saxatilis population rise

This student research was retrieved from Physis: Journal of Marine Science XI (Fall 2012)19: 58-63 from CIEE Bonaire.

Date
2012
Data type
Other resources
Theme
Research and monitoring
Geographic location
Bonaire
Author