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

Hakalau Forest National Wildlife Refuge
Comprehensive Conservation Plan
„Aiea has been documented at the western, southern, and eastern slopes of Mauna Loa, at the
southern Kohala mountains, and the northern slopes of Hualālai. The elevational range is between
260-6,000 ft. Current „aiea populations are restricted to the western side of the island from South
Kohala to Kamā„oa-Pu„u„eo. An estimated six populations currently exist, with few individuals
(1-4 plants) in each population (USFWS 1996a). In 2003, roughly 6 individuals were known within
the Kohala Forest Reserve and 165 individuals were identified near Po„ohoho„o summit (Federal
Register 2003b). Although no „aiea is known to currently occur on the KFU, plants do exist in
adjacent areas (McCandless Ranch).
The primary habitats for „aiea are lowland dry forest, montane dry forest, and montane mesic forests
dominated by „ōhi„a and koa, as well as uluhe. Several other endangered plants are known to occur
with this species (USFWS 1996a).
Three critical habitat units were established for „aiea in 2003, covering 12,708 ac. The largest unit is
within the Kīholo watershed, which is the southwestern most portion of the historical range.
Additional land is designated in the Kohala Forest Reserve and between the Kohala Forest Reserve
and the Waimanu Estuarine Research Reserve (Federal Register 2003b).
The following threats are identified in the Big Island Plant Cluster Recovery Plan (1996a): cattle,
sheep, nonnative plants, fire, and human impact. Christmas berry, fountain grass, lantana, and koa
haole have been noted as contributing to the decline of this species by increasing the risk of fire
(USFWS 1996a).
4.9.11 Phyllostegia floribunda
The erect subshrub Phyllostegia floribunda is a candidate species for listing as threatened or
endangered. As a candidate species, P. floribunda is not protected by the ESA or covered by the Big
Island Plant Cluster Recovery Plan (USFWS 1996a) or Addendum (USFWS 1998a). However, the
populations within the HAVO are provided some protection under the National Park Service Act
(16 U.S.C. §§1-18f-1) and the enabling legislation for the Park (16 U.S.C. § 396) (Pub. Law 95-635,
16 U.S.C. § 1132).
The ovate to elliptic leaves of P. floribunda are moderately hairy and pale on the lower surface. They
measure 4.7-9.4 in long and 1.8-3.3 in wide. The flowers are maroon to red and white at the base of
the floral tube. The flowers are clustered in pairs to form unbranched inflorescences. Similar to other
species in the genus Phyllostegia, the flowers are fragrant and predominantly insect pollinated. The
dry and hard fruit is a nut measuring 0.12-0.14 in long.
This species was previously found in a wide variety of locations, including the Kohala Mountains,
Ka„ū, North and South Kona, the windward sides of Mauna Loa and Kīlauea, and the windward side
of Mauna Kea (including the Laupāhoehoe Natural Area Reserve, Waiākea Forest Reserve, and
private land at Pa„auilo) (NatureServe 2007). It occurs between 1,410-3,700 ft in elevation in moist
to wet forests (Wagner et al. 1999). The current total population is believed to consist of less than
100 naturally occurring individuals and 170 outplanted individuals in 10 locations (Federal Register
2007). Most of the populations occur within the Laupāhoehoe NAR and Hawai„i Volcanoes National
Park, with additional populations in the „Ōla„a Forest Reserve, Waiākea Forest Reserves, Pu„u
Maka„ala NAR, and Kīpāhoehoe NAR. Only the populations at the Laupāhoehoe and Pu„u Maka„ala
NAR are naturally occurring. The Nature Conservancy (TNC) also outplanted 20 individuals at
4-66 Chapter 4. Refuge Biology and Habitats