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

Hakalau Forest National Wildlife Refuge
Comprehensive Conservation Plan
For the Hakalau Forest Unit, eight internal management units exist, consisting of 14,150 fenced
acres. There are 45 miles of ungulate proof fencing established, including both perimeter and internal
fences (Figure 2-1). Middle Honohina (1) is roughly 550 acres, Shipman (2) 5,000 acres, Lower
Honohina (3) 1,800 acres, Upper Maulua (4) 2,000 acres, Upper Honohina (5) 1,000 acres, Middle
Hakalau (6) 1,500 acres, Middle Papaikou (7) 1,800 acres, and Pua ‘Ākala (8) 500 acres. Middle and
Lower Maulua and Lower Honohina consist of closed canopy forest with relatively intact understory.
Middle Honohina, which has been pig free for the longest time period (since 1989), also consists of
closed canopy forest as are units B, C, E, and F.
A majority of restoration and reforestation work has been conducted within Pua ‘Ākala, Shipman,
and Upper Honohina, with over 400,000 native plants (mainly koa) outplanted since 1987 in order to
create additional native forest habitat in formerly grazed and degraded areas (see before and after
photographs below). Most recent restoration management has focused on using other native plants to
build up the understory now that koa canopy coverage has been established. Preparation of land for
outplanting includes grass control to reduce competition by using mechanical (dozer) as well as hand
control (it has been documented that pasture grasses as well as lack of seed, soil conditions, and
harsh climate (frost) in open grasslands can inhibit natural forest regeneration). In addition, listed
plants have also been outplanted in these areas including Clermontia pyrularia, Clermontia
lindseyana, Clermontia peleana, Cyanea shipmanii, Phyllostegia racemosa, and Pyllostegia velutina
and Ranunculus hawaiiensis. Native habitat vegetation in each unit can be seen in Figure 4-2, with
Middle Papaikou, Middle Hakalau, Lower Honohina, Middle Maulua and units A-F containing the
most intact native forests on the Refuge.
Intermittent streams can be found in upper elevation units 1-8, while lower elevations have perennial
streams (Figure 4-2). Additional aquatic habitats include Carex bogs found in montane wet
‘ōhi‘a/uluhe forest. Some hydrology research has been conducted. However, very little management
(other than gorse removal in the upper units) has been done for these aquatic habitats.
The invasive weeds of most concern are: (1) gorse, which is found most heavily in open pasture
areas at Pua ‘ākala, with smaller populations in Shipman and Upper Honohina, and (2) Florida
blackberry, which can be found in all units above 5,000 ft. Pua ‘Ākala also has a heavy English holly
infestation, with some smaller populations in Shipman and Upper Honohina. All three units of
Honohina and the two upper units of Maulua also have banana poka. Hotenia davidiana has the
highest concentration in Middle Honohina and the upper portions of the Lower Honohina. The
highest concentration of nonnatives is found at the higher elevations above 5,000 ft. All invasive
weeds that currently exist at HFU are in a monitoring, control, or maintenance stage of management,
with a focus on both chemical and mechanical control. Florida blackberry control activities are
conducted May-October and gorse control focused on in winter months; while English holly is yearround.
Volunteers assist with banana poka control.
Listed species management includes both flora and fauna. Listed animal species of most concern can
be found in the following units with Pua ‘Ākala and Shipman having the highest concentration of
listed species:
• ‘Akiapōlā‘au can be found in all units above 4,500 ft elevation;
• Hawai‘i ‘ākepa can be found in all units above 4,500 ft elevation with the greatest densities
in the Shipman and Pua ‘Ākala units;
• Hawai‘i creeper can be found in all units above 4,500 ft elevation;
L-2 Appendix L. Summary of Past and Current Management