Scientific Reports of the Whales Research Institute (1986)


The early postnatal growth of bottlenose dolphins and finless porpoises was studied using 97 body length records of 61 individuals born in aquariums. The growth rates observed were similar to those estimated independently for wild dolphins assuming that dentinal growth layers are deposited annually. The perinatal growth parameters thus estimated were also close to those predicted using published interspecific relationships. These results suggest that (1) the dentinal growth layers are deposited annually in these species and (2) the interspecific relationships of the parameters can be used to examine the correctness of growth layer interpretation.