Effects of long-term ungulate exclusion and recent alien species control preservation and restoration of a Hawaiian tropical dry forest
- Author:
-
Cabin, Robert J., Weller, Stephen G., Lorence, David H., Flynn, Tim W., Sakai, Ann K., Sandquist, Darren, Hadway, Lisa J.
- Title:
- Effects of long-term ungulate exclusion and recent alien species control preservation and restoration of a Hawaiian tropical dry forest
- Periodical:
- Conservation Biology
- Year:
- 2000
- Volume:
- 14
- Pages:
- 439-453
- Subject:
-
Tropical dry forests
Mamane
Sophora chrysophylla
Feral sheep
Feral ungulates
Kaupulehu
- Summary:
- While tropical dry forests are, in general, far more threatened and endangered than are tropical rain forests, the destruction of tropical rain forests receives much more attention. In addition, while eliminating grazing ungulates is often considered a key first step toward protecting the ecosystems of the dry forests, few studies have examined the long-term effects of this technique. During this study, the effects of ungulate exclusion was examined within a 2.3 ha native dry forest of the Kaupulehu preserve that is located at approximately the 600 meter elevation and 17 kilometers east of Kailua-Kona on the west side of the island of Hawaii. This study was done by comparing the present flora of the Kaupulehu preserve that was fenced more than 40 years ago, to the flora of an adjacent area that was subjected to continuous grazing since the preserve was fenced. Relative to the adjacent area, it was found that the fenced preserve contained a more diverse flora with substantially greater coverage of native overstory and understory species. However, a dominant herbaceous cover of alien fountain grass (Pennisetum setaceum) and predation by an alien rodent species appeared to have prevented the regeneration of native canopy trees. As a result, while it seemed that the exclusion of the ungulates might have been a necessary and critical first step toward protecting Hawaii's dry forests, it was found that this did not adequately preserve and maintain the remaining remnants of the forests. It was also found that efforts to control the dominant alien species within the fenced preserve may facilitate both the regeneration of the native species as well as the colonization and potential invasion of new alien plants. However, comparisons of seedlings of the dominant native canopy tree, Diospyros sandwicensis that was growing in sites that were both dominated by and free of fountain grass suggested that, while fountain grass inhibits the Diospyros seedling growth and photosynthesis, it may increase survival if seedlings are protected from ungulates.
- Label:
- Ecology - Dry Forests
- URL:
- http://cletus.uhh.hawaii.edu:2074/10.1046/j.1523-1739.2000.99006.x
- Date:
- 2000
- Collection:
- Periodicals