Pied shag, a national population review

Published:  

December 2013
This report describes the results of a national population review of pied shags.

Summary

The pied shag (Phalacrocorax varius) is a large, predominantly black and white shag which primarily inhabits inshore coastal waters and estuaries. Two subspecies are recognised; Phalacrocorax varius varius found in New Zealand and Phalacrocorax varius hyploleucus found in Australia.

Pied shag are generally considered to be widespread and moderately common, with an estimated population of 5,000-10,000 pairs and a threat ranking of National Vulnerable. However, it is likely that the population was formerly more numerous and widespread; with pied shags suffering heavy persecution in the early 1900’s.

Pied shag was identified at a high-moderate risk from fishing, primarily from poorly observed set net, inshore drift net and beach seine fisheries. At present there are no mitigation measures in place in these fisheries to protect shags, and the impacts on the population are unknown. Bycatch has also been recorded in commercial bottom longline fisheries, and little is known about bycatch in recreational fisheries. Determining fisheries related risk to pied shag is problematic as little is known about their population size and breeding distribution.

This study aimed to collate all existing knowledge to evaluate the population size and trends of pied shag in New Zealand.

Publication information

This report was commissioned by the Department of Conservation, Project POP2011-07

By M. Bell

Contact

Conservation Services Programme
Marine Species & Threats
Department of Conservation
PO Box 10 420
Wellington
Email: csp@doc.govt.nz

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