A bivoltine species is a species that has two broods of offspring per year.
Some species have a mixed strategy. For example, in some locations, the Speckled Wood butterfly (Pararge aegeria) is both univoltine and bivoltine. It is thought that this mixed strategy helps the persistence of the species in areas where the weather can be poor towards the end of the season. Larvae of the second brood run the risk of not successfully completing their development and entering diapause before the weather turns cold. Larvae following the single brood (univoltine) strategy are more likely have completed development.
A photograph of a Speckled Wood butterfly (Pararge aegeria).
Related groups of terms
Related pages on this web site
Back to Glossary