Ka Wai Ola - Office of Hawaiian Affairs, Volume 26, Number 9, 1 Kepakemapa 2009 — Wasps pushes out native species [ARTICLE]

Wasps pushes out native species

Invasive yellowjackets in forests on Hawai'i and Maui are disrupting populations of native insects, spiders, and birds, according to a study funded by the National Scienee Foundation and the Environmental Protection Agency. The western yellowjackets, or Vespula pensylvanica, are not only eompeting with native species for nectar, but are also expanding their diets to include living things as varied as birds, geckos and tree liee, said the study published in the Proceedings ofthe Naūonaī Academy ofSciences. Wasps will scavenge food from dead animals, but more than two-thirds of the wasp ehow recovered in this study was freshly killed. The ecology of the forests that the wasps inhabit is being changed rapidly as a result of the mass numbers. In the continental U.S., the wasps build nests in the spring that become dormant in the winter. But the nests thrive year-round in Hawai'i's climate, allowing for massive growth. The study was conducted at Hawai'i Volcanoes Nahonal Park and Haleakalā Nahonal Park in 2006 and 2007. One colony found on Maui housed up to 600,000 wasps, compared to a usual size of a few thousand.