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

Hakalau Forest National Wildlife Refuge
Comprehensive Conservation Plan
Obligate species known to occur on the Island of Hawai„i include endemic moths and spiders (Sinella
yoshiia, Schrankia sp., Littorophiloscia sp.). None of the obligate cave fauna known from Hawai„i
Island are currently listed as candidate, threatened, or endangered species, although two endangered
species occur on Kaua„i.
Cave invertebrate studies were conducted at KFU by Dr. Howarth and Stone of the B. P. Bishop
Museum (1998). Endemic arthropods found during this survey are listed in Table 4-3. These species
included the cave carabid ground beetle, root moths, and a fruit moth. Linyphiid spider webs were
also seen, which are likely a native species, and trails of the native Limonia crane flies (Tipulidae)
were common in cave slime. In addition, several dead moths, probably native agrotine noctuids, were
found. These moths are known to roost in caves (Howarth and Stone 1998).
4.8.4 Arthropods
Arthropods include insects, spiders, and crustaceans. There are 5,732 endemic and 101 indigenous
terrestrial arthropod species identified in the Hawaiian Islands. The majority of the native arthropod
fauna are insects (Howarth et al. 2003). Population declines of native arthropods throughout the State
have been attributed to habitat destruction and loss of host species (Howarth et al. 2003). Nonnative
ungulates, plants, and other arthropods also compete with native species and disturb their habitat
(Haines and Foote 2005).
An arthropod survey was conducted at the HFU by Howarth et al. (2003). Sampling was conducted
along a transect in the Pua „Ākala Tract, a transect in the Maulua Tract, and in the vicinity of the
University of Hawai„i Biological Field Station in the Hakalau Tract. Of the 2,500 specimens
Table 4-3. Endemic Arthropods in Three Cave Systems at the KFU.
Taxon
ARACHNID: Subclass: Acari (Mites)
Caves Surveyed
Cave 1 Cave 3 Cave 4
Unidentified
ARANEAE (Spiders)
Linyphiidae
Live
Unidentified
COLEOPTERA (Beetles)
Carabidae
Webs only
Mecyclothorax sp.
LEPIDOPTERA (Moths & Butterflies)
Carposinidae
Dead
Carposina cf. gracillima (Walsingham)
Noctuidae
Live
Unidentified Dead
Schrankia sp. A (Twilight morph)
Live Live
Schrankia sp. B (Cave morph)
DIPTERA (Flies)
Tipulidae
Live
Limonia sp.
Larval trails Larval trails
Source: Howarth and Stone (1998).
Chapter 4. Refuge Biology and Habitats 4-49