Individual study: Low-Level Forest Disturbance Effects on Primary Production, Leaf Chemistry, and Lemur Populations
Ganzhorn J.U. (1995) Low-Level Forest Disturbance Effects on Primary Production, Leaf Chemistry, and Lemur Populations. Ecology, 76, 2084-2096
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Use selective logging instead of clear-cutting
A before-and-after trial in 1990-1992 in tropical dry forest in Fôret de Kirindy, western Madagascar found that lemur encounter rates increased two years after low-intensity selective logging (<or=10% of crown area removed) for the fat-tailed dwarf lemur Cheirogaleus medius, the mouse lemurs Microcebus spp., and the Masoala fork-marked lemur Phaner furcifer. Encounter rates did not change for the brown lemur Eulemur fulvus, Verreaux's sifaka Propithecus verreauxi, Lepilelur mustelinus, and Coquerel's giant mouse lemur Mirza coquereli. Encounter rates increased from 0 to 2.8 sightings/km for the mouse lemurs Microcebus spp., from 1.5 to 4.1 sightings/km for the western fat-tailed dwarf lemur Cheirogaleus medius and from 0.5 to 0.9 sightings/km for the Masoala fork-marked lemur Phaner furcifer. However, the authors speculated that the increase was a consequence of a shift in home ranges between surveys, rather than population growth, as most of the species reproduce too slowly to cause a noticeable effect within two years. The same site was surveyed during the day and at night repeatedly and along the same trails in 1990 before logging and in 1992 after low-intensity selective logging. Authors also surveyed two additional sites, one logged in 1985-1986 and one unlogged area to control for potential year-to-year population variation.
(Summarised by JJ)