Seasonal variation in clutch size of the turtle, Dermochelys coriacea

Clutch size in sea turtles is generally reported in one of three manners. It is most often averaged over one or several nesting seasons (see Hirth, 1980 for review). However, clutch sizes may vary appreciably for iteroparous species that can deposit as many as 11 clutches a season, and patterns of variability are ob- scured by reporting only seasonal means. Clutch size trends are also documented by either following nest- ing histories of individual turtles or by comparing clutches chronologically, irrespective of the individ- uals that laid them (Frazer and Richardson, 1985a). Subsequent comparisons among studies are then con- founded by the different methods first employed to ascertain the patterns. Thus, some authors report de- creasing clutch sizes during the nesting season (Cald- well, 1959; Carr and Hirth, 1962; LeBuff and Beatty, 1971; Pritchard, 1971; Davis and Whiting, 1977 Máquez et al., 1982; Frazer and Richardson, 1985a; Mor- timer and Carr, 1987), others report an increase (Kauf- man, 1975; Bjorndal and Carr, 1989), while others report no significant change in either direction (Ehr- hart, 1982)