Reproductive Biology, Mating Aggregations, and Sexual Dimorphism of the Argentine Boa Constrictor (Boa constrictor occidentalis)

Sexual maturation in free-ranging Chilabothrus angulifer (Serpentes: Boidae)

“…Notoriously, those eight wild boas recaptured inhabited a hot cave and surroundings, a suitable habitat with large concentration of bats and apparently good shelter conditions. There is evidence that reproductive activity in the genus Chilabothrus is seasonal (Vitt andVangilder 1983, Tolson andHenderson 1993), which is consistent with most boid snakes (e.g., Fitch 1982, Vitt and Vangilder 1983, Bertona and Chiaraviglio 2003, Pizzatto et al 2006a, Pizzatto and Marques 2007, Rivas et al 2007; review in Reed and Rodda 2009). Courtship and mating in wild populations of C. angulifer occurs mainly at the onset of the rainy season, from April to June (e.g., Tolson and Henderson 1993, Morell et al 1998, this paper).…”

“…This can compromise seriously the performance of postreproductive females, to the point that many of them have to reproduce at least biennially in order to guarantee a proper recovery (fat stores duction (Lourdais et al 2004). Tolson and Teubner (1987) and Petersen et al (2015) have found evidence for free-ranging female Cuban Boas to reproduce at least biennially, which suggest that this species invest a large proportion of energy during pregnancy (see Bertona and Chiaraviglio 2003 for similar results with Boa constrictor occidentalis). So, there is a minimum optimum size required for females of each snake SVL.…”

“…This behavior was corroborated by other authors in captivity (Tolson 1983, Tolson andHenderson 1993) and by us in the wild (this paper), although it is in Cuba to talk about this phenomenon. Breeding or mating aggregations are relatively common in snakes (e.g., Bertona and Chiaraviglio 2003, Rivas et al 2007, Jellen and Aldridge 2011 this behavior has been reported in the wild are the Saint Lucia boa, Boa constrictor orophias (note that some authors consider Boa populations from the Lesser Antilles as full species) and the congeneric Jamaican boa, (Gosse 1851, Henderson and Powell 2009, Henderson and Breuil 2012. Teubner (1986) and Tolson and Teubner (1987) found that in captive Haitian boas (C. striatus) mean plasma testosterone levels of alpha-males (usually of larger size) increase with male-male agonistic interactions, whereas plasma testosterone levels of smaller males tend to decrease.…”

“…apparently require higher sizes to reach the the rule for viviparous snakes (Shine 1978, 1994, Tolson 1992, Tolson and Henderson 1993, Rivas and Burghardt 2001, 2005, Bertona and Chiaraviglio 2003. Shine (1978) suggested two main selective pressures as the causes for this snakes: (1) "female fecundity is proportional to body size, so natural selection may favor females that grow to a large size before reproducing"; and (2) "reproducing necessarily involves a even if she only produces a small clutch" (see also review of Rivas and Burghardt 2001).…”

Phenotypic plasticity of life history traits in relation to reproductive strategies in Boa constrictor occidentalis

“…Therefore, our results would indicate a trade-off between growth and reproductive lifespan to optimize body size and therefore future fecundity despite environmental constraints. It is known that female fecundity depends on body size, with larger individuals producing a higher number of offspring than smaller ones (Slip and Shine 1988;Bertona and Chiaraviglio 2003). Therefore, attaining the adult size that maximizes clutch size is a strategy to favor fecundity, although it implies reducing other parameters, such as the number of mature individuals in the population.…”