Zebra longwing or zebra heliconian - Adults roost in groups of up to 60 individuals on a nightly basis, returning to the same roost every night. These roosts provide protection to adults, the large groups deterring predators and retaining warmth.
Solitary individuals, or very small roosts, avoid exhibiting proper warning signals so as not to attract predators. Pre-roosting interactions, which consist of sitting near one another, chasing each other briefly while fluttering, or basking, occur between butterflies from separate roosts, indicating that the butterflies are aware of other roosts in their home range. Despite this, the zebra longwing chooses to form smaller aggregations.
The optimal roost size for predator deterrence is five individuals; roost size is also influenced by resource availability and foraging. H. charithonia roosts to display collective aposematism, deterring predators by conspicuously advertising their unpalatable taste.
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