As the native plants recover, so do many rare species of insects.
There are currently over 500 endemic species of pomace flies, native only to Hawaiʻi and found nowhere else in the world. The elder mānele trees in front of you are the exclusive host plants to two of these small, rare picture-wing flies,
Drosophila mimica and
Drosophila engyochracea. Ecologist Dr. David Foote has been counting the populations of these two flies periodically since the mid-1990s by attracting them to sponges marinated in a concoction of decaying mushrooms. He is encouraged about the future of
Drosophila mimica, as this species is thriving, by feeding on the rotting fruits of the recovering mānele trees. It is a much different story for the
Drosophila engyochracea, whose populations have plummeted in the last three decades. Very few flies have been observed since 2007. The villains of this story are alien predators, including yellow jacket wasps and, possibly, a newly arrived spider that lives in the bark of these mānele trees. As predators of the
Drosophila engyochracea, they are eating this species to extinction.
