536 



Fishery Bulletin 97(3), 1999 



Pohl, 1946; Forbes, 1973; Tunberg, 1986), with some 

 clear exceptions (see de Vaugelas et al., 1986). Given 

 abbreviated development in L. sinuensis and the like- 

 lihood of almost immediate settlement by decapodids 

 into the vicinity of our sample site, we expected to 

 detect distinct cohorts of small recruits, from which 

 we could estimate rates of growth to maturation. 

 However, unlike the population of the warm temper- 



3 4 



U 



Males 







13 

 11 



I 9 



Females 



B 



Males 



Females 



9 12 15 18 21 3 6 9 



Carapace length (mm) 



12 15 18 21 



Figure 6 



Linear regression (by least squares estimate for untransformed data) of chela 

 width (ChW) on carapace length (CL) for (A) males and (B) females and chela 

 height (ChH) on CL for (C) males' and (D) females in sampled Colombian 

 populations of Lepidophthalmux sinuensis. December 1991 through Decem- 

 ber 1995. The transition point at which data are subdivided, estimated by 

 piecewise linear-linear polynomial regression, was positioned to minimize the 

 sum of squares of residuals. 



ate species L. louisianensis from the Gulf of Mexico 

 (Felder and Lovett, 1989), tropical populations of L. 

 sinuensis included ovigerous females in every month 

 of sampling. This potential for continuous recruit- 

 ment over the annual cycle, coupled with our lim- 

 ited success in consistently capturing small individu- 

 als, limits clear definition of reproduction and growth 

 cycles from collections of recruits. 



Vitellogenesis in L. sinuensis was 

 evident in coloration and size changes 

 of ovaries viewed through a translu- 

 cent region of the cuticle, as in other 

 thalassinid species (Hailstone and 

 Stephenson, 1961; Forbes, 1977; 

 Felder and Lovett, 1989). The pattern 

 of change in L. sinuensis over the 

 course of maturation is as much as 

 that reported for L. louisianensis, 

 with ovaries becoming more massive 

 and opaque as maturation advances 

 (Felder and Lovett, 1989). However, 

 when tracked as an annual index of 

 reproductive activity, relative ovarian 

 width in L. sinuensis at no point 

 reached the highest mean values re- 

 ported for L. louisianensis (even af- 

 ter correcting misplaced decimals in 

 the _v-axis of Fig. 1 of Felder and 

 Lovett [1989]). We suggest that this 

 reflects year-round reproductive ac- 

 tivity in L. sinuensis, rather than in- 

 vestment in a more punctuated tem- 

 perature-modulated event as might 

 be expected in temperate latitudes. 

 It may also account for a greater 

 number of eggs on ovigerous females 

 of L. louisianensis (598 ±212; n=4) 

 than on ovigerous females of the year- 

 round reproducing L. sinuensis (251 

 + 18; «=444) (Nates et al., 1997). Even 

 so, significant fluctuations in mean 

 values for relative ovarian width did 

 occur over the three years that we 

 monitored this value in L. sinuensis, 

 with highest values preceding maxi- 

 mum abundance of ovigerous females 

 by two to three months. 



In tropical nearshore decapods, it 

 is common to have extended periods 

 of reproduction without distinct 

 peaks defined by seasonal tempera- 

 ture (Sastry, 1983; Steele, 1988; 

 Bauer, 1992; Mouton and Felder, 

 1995). However, whether modulated 

 by temperature or other factors, an- 



D 



