Reproductive patterns of Pollicipes pollicipes (Cirripedia: Scalpellomorpha) on the southwestern coast of Portugal

Abstract

The brooding period of Pollicipes pollicipes on the southwestern coast of Portugal in 1991 began in March and extended to October, and was more intense from April-September. Brooding activity in small animals (12.5-15 mm, rostrocarinal distance, RC) was significantly less than in large animals (RC > 15 mm). Brooding activity patterns of this species were considered to be similar at different tidal levels and subtidally. Crowded animals brooded less than uncrowded animals, but results could have been confounded by the fact that only one site was considered. Individuals apparently produce asynchronous broods. Estimates of the annual number of broods varied between 1 (crowded animals), 1 or 2 (small, uncrowded animals), and 4 (large, uncrowded animals). Small animals (mean RC = 15.4 mm; 16,229 eggs) produced about half the number of eggs of large animals (mean RC = 19.6 mm; 34,172 eggs). Fecundity was considered to be a function of size (RC) (after logarithmic transformation; r2 = 0.62). A variable number of eggs was produced by animals of the same size; animals with an RC from 23-25 mm ranging from 30,000-130,000 eggs per brood. Fecundity patterns were considered similar in relation to tidal level, crowding, and time in the reproductive season.