par Bernard, Tom 
Promoteur Kodikara, Sunanda K.A.S.
Co-Promoteur Dahdouh-Guebas, Farid
;Huge, Jean ;Kumara, M.P.
Publication Non publié, 2022-08-31
Promoteur Kodikara, Sunanda K.A.S.
Co-Promoteur Dahdouh-Guebas, Farid
;Huge, Jean ;Kumara, M.P.Publication Non publié, 2022-08-31
Mémoire
| Résumé : | Kalametiya lagoon, a highly threatened Sri Lankan wetland, has undergone drastic hydrological changes in the last decades, due to an upstream irrigation project. These changes led to the invasion of the lagoon water by mono-specific Sonneratia caseolaris mangroves stands and Typha angustifolia reedbeds. Kalametiya being a nationally recognized bird sanctuary since 1984, this invasion is expected to have brought significant changes on local avifauna.Therefore, this study aimed at determining the lagoon current bird diversity and distribution in relation with habitat types (i.e. Sonneratia stands, Typha reedbeds, and Sonneratia – Typha co-dominated patches) and environmental variables. Four transects covering aforementioned habitats were studied, with a total of 37 bird point-count stations.Seventy-nine bird species, including four endemics and seven near-threatened, were encountered. Invertebrate-feeders (STotal = 21, HTotal = 2,263) and polyphages (STotal = 19, HTotal = 2,483) were the richest and most diverse guilds. T. angustifolia reedbeds (SMean = 22,6 ±2,61, HMean = 2,83 ±0,31) were found richer and more diverse than S. caseolaris mangroves (SMean = 14,4 ±2,17, HMean = 2,39 ±0,16) (t = 3, df = 5,10, p-value = 0,029). Feeding guild composition was significantly influenced by several environmental variables, thus guilds could have great potential as bioindicators of the ecosystem if further studies are done to explore these relationships.Considering the important bird diversity found in Kalametiya and its main habitats, this research brings additional proof that a management aiming at completely restoring the lagoon to its past state would be detrimental to its avifauna. |
