Reproductive Ecology of Dry Season Ornithophilous tree species

Bombax ceiba (Bombacaceae), Erythrina variegate var. orientalis (Fabaceae), Alangium salvifolium (Alangiaceae) and Spathodea campanulata (Bignoniaceae)bloom and produce fruits for seed dispersal during dry season. B. ceiba is a self- incompatible, obligate outcrosser, switching to ornithophily. E. variegata is an ornithophile. S. campanulata is a self-incompatible, obligate outcrosser, switching to ornithophily. A.salvifolium is a generalist flower, adapted to birds and bees. In A. salvifolium, fruits are fleshy, and attract birds which act as seed dispersal agents. In all other plants, the fruits are hard without any pulp. In S. campanulata and B.ceiba, fruits dehisce to release seeds for dispersal by wind. In E.variegata, fruits are indehiscent and seed release when fruit coat degrades. Bird-pollination is expensive for plants. They are far flying and systematic pollinators effecting mostly outcrossing. Dry season is the most crucial period for birds due to water stress and dehydration. Therefore, dry season flowers play a vital role in sustaining avian as well as other animals during the dry season.