Duarte et al: Relative growth, population structure, and reproductive biology of slipper lobsters (Scyllaridae) 
63 
Spatial distribution of sampled effort of the double-trawler and pot-and-trap fleets that 
caught hooded slipper lobster (Scyllarides deceptor) off southeastern Brazil, within the es- 
tablished 5 fishing areas (outlined with dashed lines) from May 2006 through April 2007. 
and Lavalli and Spanier (2007) mentioned the rapid 
calcification of the exoskeleton in species of this family, 
with the ovigerous condition occurring shortly thereaf- 
ter. These observations agree with the finding from our 
study that the relative proportion of ovigerous females 
of the hooded slipper lobster is greater during August- 
September than in other periods and with the results 
of Oliveira et al. (2008). 
Another period in our study with a large proportion 
of ovigerous females occurred during January-Febru- 
ary, indicating that there are 2 spawning seasons for 
the hooded slipper lobster. Lavalli and Spanier (2007) 
previously reported this spawning period for other Scyl- 
larides species. Larvae released in September would 
experience a period of high primary production in the 
environment during October-March, when nutrients 
from the South Atlantic Central Water are present in 
shallower water (Rossi-Wongtschowski and Madureira, 
2006). This reproductive strategy increases the prob- 
ability of larval survival because complete larval de- 
velopment for Scyllarides spp. requires approximately 
8 months (Booth et al., 2005). 
The range of fecundity values and mean fecundity 
of hooded slipper lobster in this study were similar to 
those values reported for other species of the same ge- 
nus (see review by Oliveira et al., 2008). According to 
these authors, hooded slipper lobster (n= 29) had fecun- 
dities between 58,871 and 517,675 eggs (mean=191,262 
eggs (SD 17,811). 
Research by Vazzoler (1996) suggested that the early 
maturity of a species lowers fecundity and increases oo- 
cyte size to preserve energy per egg and improve larval 
survival and reproductive success. This reproductive 
strategy is evident in Scyllaridae, as seen in the rela- 
tionship between the mean sizes of lobster species and 
their gonadal maturation, fecundity, and egg diameter. 
According to Oliveira et al. (2008), the species of Iba- 
cus and Thenus showed lower fecundity (13,000-21,000 
eggs) and larger egg diameters (1. 1-1.2 mm) than the 
fecundity (90,000-224,000 eggs) and egg diameters 
(0.60-0.67 mm) of species of Scyllarides. This observa- 
tion reflects the reproductive strategy in Scyllaridae, 
which appears to differ depending on the bathymetric 
distribution of a given species. Species that are coastal, 
for example, tend to have lower fecundity and larger 
egg sizes (e.g., the flathead lobster and butterfly fan 
lobster, according to Courtney et al. [2001] and Stewart 
et al. [1997]) than species that inhabit deeper waters 
(e.g., the blunt slipper lobster, according DeMartini et 
al. [2005], and the hooded slipper lobster, as observed 
in this study). 
Results from our study indicate that females of the 
hooded slipper lobster reach a larger size (maximum 
TL) than males (female: 36.0 cm TL; male: 32.6 cm TL), 
