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bioRxiv · 10.1101/2020.06.09.141796

Taking fright: the decline of Australian Pied Oystercatchers Haematopus longirostris at South Ballina Beach, New South Wales

Totterman, S.
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Abstract

This study reviewed data from the Richmond River Area Pied Oystercatcher Protection Program 1997-2013 and Richmond River Area Shorebird Protection Program 2014-2018, on the far north coast of the State of New South Wales (NSW), Australia. The Australian Pied Oystercatcher Haematopus longirostris breeding population size for South Ballina Beach has decreased from 15-16 pairs in 1994-1996 to 7-9 pairs in 2016-2018. This is despite control of the European Red Fox Vulpes vulpes successfully reducing depredation of eggs and chicks and > 207 oystercatchers fledging from beaches in the Richmond River area in 1997-2018. The negative trend for South Ballina is contrasted with the positive trend for Bombing Range Beach, where the population size has increased from 4-5 pairs in 2002-2004 to 8-9 pairs in 2016-2018. Vehicle-based recreation has increased at South Ballina in the past two decades versus Bombing Range has remained closed to the public. It is proposed that human recreation disturbance is preventing recruitment into the South Ballina oystercatcher breeding population. Without strong protection of habitat from such disturbance, the NSW oystercatcher breeding population size is predicted to continue to decrease.

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Totterman, S.. 2020-06-11. Taking fright: the decline of Australian Pied Oystercatchers Haematopus longirostris at South Ballina Beach, New South Wales. https://doi.org/10.1101/2020.06.09.141796

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