The Gulf of Mannar (GoM), India, includes 21 coral islands (8°N; 79°E), covers an area of 10,500 sq. km and supports 94 species of corals belonging to 37 genera. Kappaphycus alvarezii, a Philippine-derived rhodophyte, has been introduced into the GoM for commercial cultivation in 2002. The ecological threat from this invasive alga to coral species in GoM was first indicated by Pereira and Verlecar (2005). After 6 years of its introduction, its bioinvasion on branching corals (Acropora species) in the Kurusadai island (9°15¢N; 79°12¢E) of GoM was reported in 2008 (Chandrasekaran et al. 2008). Consequently, commercial cultivation of this invasive alga was prohibited. A mechanical removal programme started in 2009 by the State Government at the invaded site could not deliver expected results. Thus, this alga enjoys a freedom of unrestricted spread and aggressive growth in GoM, predominantly on species of Acropora. On 28 April 2010, during our routine sampling visit at Kurusadai Island, unusual appearance of K. alvarezii, on the cup coral, Turbinaria sp. was observed (Fig. 1a). The space between the plates of Turbinaria sp. provides an ideal settlement surface for K. alvarezii, which protect them from the wave action and favour the profuse growth of secondary branches of K. alvarezii between the plates (Fig. 1b) in contrast to the smothering effect on the top of coral plates (Fig. 1c). This finding shows that K. alvarezii is capable of invading species of nonbranching corals as reported in Hawaii for Montipora capitata and Porites compressa (Conklin and Smith 2005). Therefore, perhaps this is the first report from India on bioinvasion of K. alvarezii on a non-branching coral (Turbinaria sp.) in the GoM.

The diversity of birds in Koonthankulam pond, located in Koonthankulam village (8.495N, 77.755E), Tirunelveli district, southern Tamil Nadu, was studied. A total of 90 species belonging to 21 orders, 42 families, and 73 genera were recorded. The study recorded seasonal migrants such as Black Ibis, Oriental White Ibis, Bar-headed Goose & Spoonbill and indigenous species including the Pond Heron, Cattle Egret, White-breasted Kingfisher, Red-wattled Lapwing, Rose-ringed Parakeet, Purple-rumped Sunbird, Hoopoe, and Indian Robin. The primary data were analyzed by principal component analysis, cluster, and analysis of variance. Analysis of variance showed that the Menhinick index is statistically significant P <0.05.  A structural equation model was applied to analyze the physico-chemical parameters of water samples collected from the sampling site. Analysis of experimental data through the structural equation model indicates temperature and dissolved oxygen may indirectly affect bird diversity.

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