All field studies indicate that Indri indri is highly folivorous with the majority of its feeding time spent on immature foliage. At Mantadia, 72.3% of feeding time was devoted to immature leaves with a reduced emphasis on fruit seeds/whole fruits (16.4%) and flowers (6.7%) (Powzyk, 1997; Powzyk and Mowry, 2003). Indri observations at Betampona yielded similar results: 73.4% of total feeding records were on immature foliage, followed by 8.2% on fruit/fruit seeds and 5.3% on flowers (Britt et al., 2002). Pollock (1977) reported 34.3-43.8% of feeding time at Analamazaotra on unknown plant parts, yet when food items were identified, the majority were on leaves (32.4-37.0%), followed by fruits (23.8-26.4%) and flowers (0.0-2.3%).
Other notable items in Indri indri's diet were galls (1.37%) and other plant parts (3.22%), including bark, stems, leaf petioles, and new branch tips (Powzyk, 1997). Plant galls were a much sought after food item at Mantadia for Indri, but were more ephemeral in their availability than either fruit or flowers. A plant gall is a tumorous growth of cells typically initiated by a microscopic insect (or a bacterium or fungus), which then feeds on the nutritious tissue (i.e., amino acids) (Koyama et al., 2004). Indri likely consumes galls for the same vital nutrients. Indri's consumption of plant galls and fruit were nearly indistinguishable from one another because of similarities in the shapes and handling of these items. Confirmation of gall feeding was only made after collecting gall-infested foliage directly from a food tree (Powzyk, 1997).
Overall, phenological monitoring at the Mantadia site showed that palatable immature leaves were both available and abundant year round for Indri, as were palatable fruit and flowers, albeit at comparatively lower levels (Figure 2) (Powzyk, 1997; Powzyk and Mowry, 2003).
Indri indri did consume mature leaves, although their contribution to the annual diet varied between research sites. At Betampona, 7.2% of total feeding records were on mature leaves (Britt et al., 2002), while Indri at Mantadia ate mature foliage just 1.4% of feeding time (Powzyk, 1997). Although not a major food constituent, Mantadia Indri fed on mature foliage from 12 different plant species, including "kijiabonaka" (Symphonia fasciculate, Clusiaceae) whose mature leaves were so thick and crunchy, they mimicked the sounds of fruit consumption (Powzyk, 1997). In contrast, Betampona Indri consumed mature leaves from 25 different plant species, with peak consumption in April and October when young leaf availability was reduced (Britt et al., 2002). It is unclear whether this disparate finding is due to observer differences in the classification of mature foliage, or differences in available food items within a forest type. Nevertheless, Indri in Betampona appeared to rely more heavily on mature leaves than Indri at other study sites.
An unusual food item consumed by Indri indri at both Mantadia and Betampona was tree bark. Indri consumed bark at Mantadia 2.86% of the total feeding time a a
Was this article helpful?
All Natural Immune Boosters Proven To Fight Infection, Disease And More. Discover A Natural, Safe Effective Way To Boost Your Immune System Using Ingredients From Your Kitchen Cupboard. The only common sense, no holds barred guide to hit the market today no gimmicks, no pills, just old fashioned common sense remedies to cure colds, influenza, viral infections and more.