The Impact of Oil Palm Conversion on Tropical Amphibians.
Abstract
Agriculturally-altered habitats, especially oil palm plantations, are rapidly
dominating the Southeast Asian landscape. Although recent studies have
shown reduced species diversity associated with this commodity, data on
amphibian diversity are rare. The following thesis explores the impact of
oil palm plantations on amphibians in Peninsular Malaysia based on (1)
amphibian biodiversity, (2) quality and use of breeding sites, (3) habitat
use and (4) parasitism. Contrary to expectation, not all metrics of
biodiversity differed between oil palm plantations and secondary forest
sites. Amphibian community composition, however, differed greatly between
the two habitat types, with oil palm communities being dominated
by species known to prosper in disturbed habitats, indicating that the
community is currently of limited conservation value. Within plantations,
temporary pools were found to serve as important breeding habitats for
amphibians so a focused study on the characteristics of these pools was
carried out. Although we found differences between pools, the proportion
of occupied pools did not differ significantly between plantation and forest
sites. I did observe evidence of breeding site preferences of least concern,
plantation amphibians, along with habitat partitioning between species,
a similar pattern also seen in forest communities. I compared parasite
burdens between habitats by screening for the fungus Batrachochytridium
dendrobatidis (Bd) and for nematode parasite load. Bd was not detected in
any of my samples and there was no difference in nematode loads between
habitat types. However, patterns of nematode prevalence was affected
by host type, while nematode intensity was dependent on an interaction
between host and body size. The final chapter indicates that in terms
of parasite, the host environment is the most important. Additionally,
differences in host-parasite patterns between habitats indicate a possible
underlying problem that rapid biodiversity censuses would be unable to
detect.
Authors
Faruk, AisyahCollections
- Theses [3702]