Germination of Seed Ingested by Hornbills in Khao Yai National Park, Thailand

Penwadee Suklim, Vijak Chimchome, Chatchai Ngernsaengsaruay, Kanchit Srinopawan, Pilai Poonswad



Hornbills, large frugivorous birds, have long been known as good seed dispersers, especially for large-seed plants. The aim of this study was to investigate whether seeds passed through the hornbill?s digestive tract can remain intact and help promote germination and survival of ingested plants. The study was conducted in Khao Yai National Park (KYNP), Thailand from January to November 2018. Two out of four sympatric hornbill species, i.e., Great Hornbill (Buceros bicornis) and Oriental Pied Hornbill (Anthracoceros albirostris) were observed. Ingested seeds were collected from under the active nest trees and planted in a nursery as a ingested seed group; in comparison, ripe fruits were collected under parent trees, as a control group of the same plant species. The result showed that e out of 11 species from the ingested seed group were higher in percentage of germination (PG) compared to the control group. All species from ingested seed group germinated faster on average. Ingested seeds of all sizes were higher in PG. Small seeds seem to have higher PG. Ingested seeds from all three fruit types were higher in PG than in the control group (i.e., berry, capsule and drupe). Both groups were either promoted or inhibited seedling survival. Bhesa robusta is a good example that without hornbill ingestion, no control seeds germinated at all, which indicates that conserving hornbill plays an important role in maintaining not only this fruit species but possibly also for some other wild fruit species in KYNP forest ecosystem.