Final Comprehensive Conservation Plan - U.S. Fish and Wildlife ...

Hakalau Forest National Wildlife Refuge
Comprehensive Conservation Plan
In addition, Hawai„i Island is home to candidate endangered species, as well as species of concern
(SOC). Species of concern do not receive legal protection, but might be in need of concentrated
conservation actions. Eight candidate endangered arthropod species occur, and more than 100 species
of concern are listed (Howarth et al. 2003). Some of these are expected to occur in the Hakalau
Forest NWR. The HFU shelters a number of candidate endangered damselfly species in the endemic
genus Megalagrion (Howarth et al. 2003).
Table 4-2. Endangered and Rare Native Invertebrate Species Occurring or
Potentially Occurring on the Hakalau Forest NWR.
Family Genus Hawai‘i Island
Listed
Species
Candidate
Species
COLEOPTERA (Beetles)
Aglycyderidae Proterhinus 23 0 0 0
Cerambycidae Plagithmysus 39 0 0 12
Curculionidae Rhyncogonus 2 0 0 1
Elateridae Eopenthes 3 0 0 2
DIPTERA (True Flies)
Drosophilidae Drosophila 141 3 1 0
HYMENOPTERA (Wasps, Bees & Ants)
Colletidae Hylaeus 28 0 0 17
LEPIDOPTERA (Moths & Butterflies)
Crambidae Omiodes 19 0 0 10
Geometridae Scotorythra 20 0 0 0
ODONATA (Dragonflies & Damselflies)
Coenagrionidae Megalagrion 9 0 2 2
Source: Howarth et al. (2003), Haines and Foote (2005).
4.8.1 Picture-wing Flies (Drosophila)
In Hawai„i, the genus Drosophila contains over 600 endemic species of picture-wing flies. The
Hawaiian drosophilids have been thoroughly studied throughout the State, beginning with genetic
and evolution studies in the 1963 Hawaiian Drosophila Project (Howarth and Mull 1992). Within this
genus, 11 species are listed as federally and State endangered species, a single species is listed as
threatened, and 2 species are listed as candidate endangered species. Of the endangered species, two
can be found on the Island of Hawai„i: Drosophila heteroneura and Drosophila ochrobasis (Federal
Register 2008b). A third species found on the island, Drosophila mulli, is listed as threatened and a
candidate endangered species, Drosophila digressa, is restricted to Hawai„i Island.
Drosophila surveys at the KFU were conducted in November 1999 and February 2000 using sponges
baited with fermented mushrooms and bananas. Six species of endemic picture-wing flies were
observed on the KFU including D. basisetae, D. conspicua, D. heteroneura, D. silvestris, D. sproati,
and D. tanythrix. Nearly all of the drosophilids were found on the 4,500 ft transect (Foote 1999).
Only one species found on the KFU is listed as endangered: Drosophila heteroneura. Of the
314 picture-wing flies collected on the Refuge, 37 percent were identified as D. heteroneura, making
it the most abundant picture-wing fly on the Refuge unit. In addition, D. heteroneura observed
during the KFU survey were the first observations of this species in the wild in approximately
4-46 Chapter 4. Refuge Biology and Habitats
SOC