Volume 46, No. 2

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Illegal egg harvesting and population decline in a key pelagic seabird colony of the Eastern Indian Ocean


1Department of Ecology and Environmental Sciences, Pondicherry University, Kalapet, Puducherry 605014 India (
2Centre d'Ecologie Fonctionnelle et Evolutive, UMR 5175 and CNRS - Université de Montpellier - Université Paul-Valéry Montpellier - EPHE, Montpellier, France
3Percy Fitzpatrick Institute of African Ornithology, NRF-DST Centre of Excellence at the University of Cape Town, Rondebosch 7701, South Africa


MONDRETI, R., DAVIDAR, P. & GRÉMILLET, D. 2018. Illegal egg harvesting and population decline in a key pelagic seabird colony of the Eastern Indian Ocean. Marine Ornithology 46: 103 - 107

Received 23 December 2017, accepted 27 April 2018

Date Published: 2018/10/15
Date Online: 2018/6/15
Key words: seabird population decline, illegal egg harvesting, Indian Ocean, pelagic seabird colony, Sooty Terns


We carried out population counts of a nesting colony of terns (Sternidae) on Pitti Island, an official seabird sanctuary, on 17 February 2013, 10 March 2013, and 10 February 2014. We also assessed population trends over previous years using data from earlier surveys. We estimated the number of nests and eggs, and recorded loss of eggs by predation, including harvesting by fishermen. Using a structured questionnaire, we interviewed 800 respondents from Kavaratti Island in the Lakshadweep Archipelago to assess the number of people involved in seabird egg harvesting and trade, and to evaluate their attitudes towards seabird conservation. We recorded three species of terns: Sooty Tern Onychoprion fuscatus, Brown Noddy Anous stolidus, and Greater Crested Tern Thalasseus bergii, but only Sooty Terns were nesting during our field visits. Levels of natural predation on this species were low (<1%), whereas fishermen removed 14%-45% of the eggs. Approximately 72% of the 800 respondents interviewed on Kavaratti Island were either directly or indirectly involved in the harvest and local trade of seabird eggs. Respondents involved in egg harvesting were significantly less inclined to support seabird conservation. Although Pitti Island is a protected area, tern numbers have declined since 1963. This key breeding site will likely be lost unless stringent conservation measures are implemented to monitor and protect the nesting colony, and to divert the local people away from the seabird egg trade.


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