Kathy Carlstead, a researcher at the Honolulu Zoo, goes to some trouble to make life more interesting for the Hawaiian honeycreepers she is studying. Every day she collects stalks of flowers from various flowering shrubs, puts them in small plastic tubes filled with water, and clips the tubes to branches in the birds' cage. Despite the plentiful supply of nectar available from a feeder in their cage, the birds seem to enjoy extracting nectar from the flowers. And instead of just eating their usual daily bowl of fly larvae, the birds hunt down and catch fruit flies that Carlstead raises for them.