Association of cobia,Rachycentron canadum,with cownose ray,Rhinoptera bonasus

Field and laboratory observations on an association of cobia,Rachycentron canadum with cownose ray,Rhinoptera bonasus are reported. Cobia main-tained a position in close proximity to the back of the rays. The cobia would move away from the rays to take food presented. This opportunistic and probably facultative feeding on rejected food scraps or displaced benthos may be the first step in the evolution of commensal attachment as has been shown for the remoras.