Koki'o (Kokia kauaiensis)

views updated

Koki'o

Kokia kauaiensis

StatusEndangered
ListedOctober 10, 1996
FamilyMalvaceae (Mallow)
DescriptionA tropical tree.
HabitatMesic, tropical forest.
ThreatsHabitat loss, introduced mammalian herbivores, damage by non-native plants.
RangeHawaii

Description

The koki'o is a tree that grows as tall as about 33 ft (10 m). It has roughly circular leaves, 5-10 in (12-25 cm) wide, with 7-9 lobes, and a heart-shaped base. The brick-red flowers are solitary but clustered near the ends of the branches on stout stalks 1.2-3.5 in (3-9 cm) long. The broadly egg-shaped floral bracts are 1.5-2.4 in (4-6 cm) long and hairless except near the base. The curved petals are 4-6 in (10-15 cm) long, twisted at the base, and densely covered with silky, yellowish hairs. The ripe fruit is an egg-shaped capsule, containing ovoid seeds 0.4-0.5 in (10-12 mm) long and densely covered with reddish, woolly hairs up to 0.4 in (10 mm) long. This species is distinguished from others of its endemic Hawaiian genus Kokia by the length of the bracts surrounding the flower, the number of lobes and width of the leaves, the length of the petals, and the length of the hairs on the seeds.

Habitat

The koki'o typically grows in native, species-rich, mesic, tropical forest at elevations between 1,960 and 2,600 ft (475 and 795 m).

Distribution

The koki'o is a locally evolved, or endemic species that is only known from northwestern Kauai, one of the Hawaiian Islands. The Hawaiian archipelago has an extremely large fraction of endemic species; about 89% of the indigenous flowering plants occur nowhere else in the world.

Threats

The greatest threats to the koki'o are due to habitat degradation and competition associated a number of invasive non-native plants, including the lantana (Lantana camara ), sweet granadilla (Passiflora ligularis ), air plant (Kalanchoe pinnata ), and Sacramento bur (Triumfetta semitriloba ). Also important are habitat degradation and browsing by introduced mammalian herbivores (especially pigs, deer, and rats), erosion, and the risks inherent in having a tiny population size and very limited distribution. The koki'o is historically known from six scattered populations on northwestern Kauai, but only five of these could be relocated in the mid-1990s. The five surviving populations occur on State land in the following areas: Paaiki Valley; Mahanaloa-Kuia Valley junction; the western side of Kalalau Valley and Pohakuao Valley; and Koaie Stream branch of Waimea Canyon. The three largest populations each contain 30 to 70 individuals, while the others have fewer than 10. The total number of individuals is 145 to 170.

Conservation and Recovery

The known populations of the koki'o are on state-owned land, including parks and other conserved natural areas. As such, this endangered plant is protected from any harvesting. However, the state has limited funding available for enforcement of no-take laws, and for the management of critical habitat to reduce the degradation caused by introduced mammalian herbivores and invasive plants. Effective conservation of the koki'o requires intensive management of its habitat to reduce the damaging effects of non-indigenous species. In addition, the tiny surviving population must be monitored against future change. Research should be undertaken to develop a better understanding of the degrading influences faced by the endangered plant, and of ways of mitigating those damages. Work should also be undertaken on propagation of the rare plant in captivity, with a view to producing stock for out-planting into the wild.

Contacts

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
Telephone: (503) 231-6121
http://pacific.fws.gov/

U. S. Fish and Wildlife Service
300 Ala Moana Boulevard, Room 3108
P.O. Box 5088
Honolulu, Hawaii 96850-5000
Telephone: (808) 541-3441
Fax: (808) 541-3470

Reference

U. S. Fish and Wildlife Service. 10 October 1996. "Endangered and Threatened Wildlife and Plants: Determination of Endangered or Threatened Status for Nineteen Plant Species From the Island of Kauai, Hawaii." Federal Register 61 (198): 53070-53089.

More From encyclopedia.com