Astacoides - Biology

Biology

Very little field work has been carried out on Madagascan crayfish, leaving their biology poorly known. They are slow-growing animals, among the slowest of any crayfish; A. crosnieri may take 10 years to reach a carapace length of 30 mm (1.2 in). They appear to breed once a year, with females bearing eggs for around four months, peaking from July to October. The eggs hatch in October or November, and the juveniles are independent by January.

The fish Channa maculata is an invasive species in parts of Madagascar, and it is known to feed on young crayfish. Astacoides is also harvested by local people, often before the crayfish are able to reach reproductive age. The greater threat to Astacoides crayfish, however, is from habitat loss. The importance of habitat loss may have been underestimated in the past because most studies have focussed on the Ranomafana National Park, where the forests are largely intact but crayfish are still harvested by local people.