Hi Dennis,
You're right, there would be a lot of variation of predatory species within B. Schlegelii's range. Any opportunistic predators would be happy to eat this species but as far as I know there is not one particular species that preys exclusively on them or that inflicts a large proportion of juvenile deaths. Predatory birds, coatimundis and perhaps even small cats like ocelots may prey on this species.
As for the impact on population, predation is a huge factor among most snakes preventing juveniles from reaching adulthood. As a rule of thumb in biology, one can estimate what percentage of a species reaches adulthood by looking at it's fecundity. The more offspring produced in a clutch or litter, the fewer are expected to reach breeding age. With most cluch sizes being 10-12 young, it would take about 1 snake every clutch of two to keep the population stable so to answer your question, yes predation probably plays a significant role in juvenile mortality of B. schlegelii, as for the exact predatorty species and their specific impacts, I don't know where you'll be able to find that kind of information.
