Volume 45, No. 1

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Status and diet of the European Shag (Mediterranean subspecies) Phalacrocorax aristotelis desmarestii in the Libyan Sea (south Crete) during the breeding season


1Natural History Museum of Crete, University of Crete, P.O. Box 2208, Heraklion 71409, Crete, Greece (
2Institute of Marine Biology, Biotechnology & Aquaculture, Hellenic Centre for Marine Research (HCMR), P.O. Box 2214, Heraklion 71003, Crete, Greece
3Fisheries Research Institute, Hellenic Agricultural Organization DEMETER, Nea Peramos, Kavala 64007, Macedonia, Greece
4Department of Biology, University of Crete, P.O. Box 2208, Heraklion 71409, Crete, Greece


XIROUCHAKIS, S.M., KASAPIDIS, P., CHRISTIDIS, A., ANDREOU, G., KONTOGEORGOS, I. & LYMBERAKIS, P. 2017. Status and diet of the European Shag (Mediterranean subspecies) Phalacrocorax aristotelis desmarestii in the Libyan Sea (south Crete) during the breeding season. Marine Ornithology 45: 1 - 9

Received 21 June 2016, accepted 21 September 2016

Date Published: 2017/04/15
Date Online: 2017/02/28
Keywords: breeding biology, diet, Gavdos Island, European Shag, Mediterranean subspecies


During 2010-2012 we collected data on the population status and ecology of the European Shag (Mediterranean subspecies) Phalacrocorax aristotelis desmarestii on Gavdos Island (south Crete), conducting boat-based surveys, nest monitoring, and diet analysis. The species' population was estimated at 80-110 pairs, with 59% breeding success and 1.6 fledglings per successful nest. Pellet morphological and genetic analysis of otoliths and fish bones, respectively, showed that the shags' diet consisted of 31 species. A total of 4 223 otoliths were identified to species level; 47.2% belonged to sand smelts Atherina boyeri, 14.2% to bogues Boops boops, 11.3% to picarels Spicara smaris, and 10.5% to damselfishes Chromis chromis. Our results revealed that, during the breeding season, the European Shag feeds mainly on small demersal species that are of low commercial value, posing no significant threat to the conduct of local fisheries.


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