Role Of Lemurs (Eulemur Coronatus And Eulemur Sanfordi) In Forest Regeneration In Amber Mountain National Park, Madagascar

A study on two lemurs, Eulemur coronatus (Gray,1842) and Eulemur sanfordi (Archbold,1932), was carried out in the humid tropical forest of Amber Mountain National Park, Madagascar. This research aimed to study the influence of the two endemics lemurs species in forest regeneration in Amber forest which involves:first the study on their feeding ecology to know better their dependence on Amber forest; then the study on their effects of gut-passage on the germination of seeds to determine their role as seed dispersers; and finally the study on seedlings growth to understand their importance to the habitat regeneration and conservation strategy of Amber forest. A comparative study was also performed between two lemurs in the Amber Mountain National Park to determine their living interactions and also to compare their ability in forest regeneration.A specific group of E. coronatus and E. sanfordi composed of 8 and 9 individuals, respectively were followed, observed and monitored during 396 hours from the end of the dry season (September 2013- November 2013) to the beginning of the rainy season (December 2013-February 2014) to collect information on their feeding ecology and defecation. The data collection on germination and seedling period were followed until February 2015. Field observers on feeding ecology data recorded the food items taken, plant species consumed, plants organs preferred, the feeding layer and characteristics of plants species consumed by these two lemurs species. Feces samples of E. coronatus and E. sanfordi being followed were collected and analyzed in order to extract seeds. Fecal seeds were counted, measured and identified. Distance travelled of fecal seeds were study by mapping the geographical coordinates between mother tree and deposited seeds using QGIS software. The most common seeds in lemurs’feces were used to germination test. It allowed analysis of the germination potential of the collected seeds by planting defecated and non passed seeds in a nursery. The data of seedlings survival and growth were recorded every months by counted and measured the seedlings.The results of this study demonstrate that:E. coronatus spent 32% of their time feeding. It varied significantly across the months (F=5.02, p=0.01) and seasons (F=4.97, p=0.03). E. sanfordi spent 24% of their time feeding. It varied significantly across the months (F=4.59, p=0.01). But it did not vary significantly across the seasons. The differences in feeding time between these two lemurs species were significant during all study period (U=1158,p=0.01). Fruit are the mainly food in both lemurs’ diet. E. coronatus spent 92% of their feeding time eating fruit including ripe fruit (58%) and unripe fruit (34%). Feeding time on ripe fruit was high in all months. The amount of time lemurs spent feeding on ripe fruit varied significantly across the months (F=5.12,p=0.01). Feeding time spent on eating ripe fruit did not vary significantly across the seasons (F=2.06, p=0.16). E. sanfordi spent 80% of their feeding time eating fruit including ripe fruit (76%) and unripe fruit (4%). Feeding time on ripe fruit was high in all months. The amount of time lemurs spent feeding on ripe fruit varied significantly across the months (F=8.80, p=0.01) and the seasons (F=36.36,p=0.01). The differences in feeding on ripe fruit between the species that was not significant. E. coronatus consumed 45 plants species belonging to 27 families and 39 genera.55.56% of plants consumed are endemic. The number of plant species did not vary significantly across the days (F=0.57, p=0.85) but they varied significantly across the months (F=4.47, p=0.02) and seasons (F=8.39, p=0.05). E. sanfordi consumed 34 plant species belonging to 25 families and 30 genera.70.59% of plants consumed are endemic. The number of plant species did not vary significantly across the days (F=0.83, p=0.61), the months (F=6.65, p=0.66) and seasons (F=0.51,p=0.48). The differences were significant (U=1439,p=0.01). Plant species in Moraceae family were the most consumed by both lemurs. E. coronatus spent most of their total feeding time in upper tree layer. E. sanfordi spent 60% of their total feeding time in the emergent layer of large tree tops. Both lemurs used all forest layers for feeding but the differences are not significant (U=11,p =0.75). Both lemurs consumed the most plant species in DBH between 10 and 20 cm and height between 10 and 20 m.502 seeds were extracted from 129 fresh fecal samples collected from E. coronatus. They represented 33 different species belonged to 23 families.528 seeds were extracted from 131 fresh fecal samples collected from E. sanfordi. They represented 25 different species belonged to 17 families. Both lemur species had more than 50% of collected feces contained< 2 seeds. They had also more than 70% of collected feces contained< 2 seeds species. E. coronatus was estimated to disperse seeds away from parent trees by a mean distance of 97.71 m whereas E. sanfordi was estimated to disperse seeds away from parent trees by a mean distance of 119.64 m. For both lemurs, passed seeds had a higher germination rate and shorter average latency period than control seeds. But, E. sanfordi had a higher germination rate and shorter average latency period than E. coronatus. The Mann-Whitney test analysis had different levels of significance. Seedling from both lemurs’gut-passed seeds had higher seedling rate, average of seedling growths and seedling heights than control seeds. Seedling from E. coronatus’gut-passed seeds had higher seedling rate, average of seedling growths and seedling heights than those from E. sanfordi. The Mann-Whitney test analysis had different levels of significance.Thus, E. coronatus and E. sanfordi depend on endemic plant community in amber forest for their daily needs and some differences found in their diet may permit their coexistence in same area. E. coronatus and E. sanfordi are important seeds disperser within the forest. They contribute to the conservation of plant diversity and seeding regeneration in the Amber forest ecosystem. They may play an important role in natural afforestation process if much attention is focused on protecting them from human threats.