skip to content
Government of Western Australia - Department of Fisheries
Friday 22 April 2016

Fisheries confirms likely cause in Broome fish deaths

The Department of Fisheries has confirmed that the recent fish kill north of Broome was likely caused by local environmental factors which made fish susceptible to a naturally occurring bacterial infection.

Since March 15, the Department of Fisheries has been investigating a marine fish kill around 70 kilometres north of Broome.

Following an initial report by a member of the public of dead and dying fish on a beach in the Manari area, the department undertook thorough investigations to determine the extent and cause of the fish kill.

Fish deaths were observed along approximately 60 km of coast, north to Cape Bertholet and south to Willie Creek and also some distance off the Kimberley coast within an algal bloom.

The department’s investigations included beach and vessel surveys, an aerial survey, examination of local environmental factors, and comprehensive testing and analysis of fish and water samples by specialist laboratories.

Testing included examination of water and phytoplankton samples for the presence of harmful or toxic algal species and the screening of fish tissue samples for evidence of a broad range of algal and chemical toxins.

Scientists advised that the fish deaths were due to a systemic bacterial infection, which test results later confirmed was caused by the bacteria Streptococcus iniae. This is consistent with the symptoms seen in dead and dying fish in initial reports.

Streptococcus iniae is a major fish pathogen implicated in fish kills around the world, in both wild and aquaculture fisheries. This bacterium occurs naturally and is considered opportunistic, with serious infections arising mostly in stressed animals.

Scientists are confident that local environmental factors, including high water temperatures in particular, stressed the fish making them susceptible to the bacterial infection. These environmental factors are also likely to be associated with the observed algal bloom in the region, which tests indicated was not the cause of the fish deaths.

Department of Fisheries Biosecurity Section Leader, Victoria Aitken said the department greatly appreciates the assistance and support of the local community who provided helpful information throughout the incident.

Ms Aitken said that the department would release a public report on its findings and use learnings from this incident to further develop and improve its incident management processes.

Any fish kills should be reported to FISHWATCH on 1800 815 507.

More information about fish kills can be found on the Department of Fisheries website at www.fish.wa.gov.au

Last modified: 22/04/2016 12:40 PM

wa.gov.au

© All contents copyright Government of Western Australia. All rights reserved. ABN: 18 951 343 745

Copyright

© This work is copyright. You may display, print or reproduce this material only in an unaltered format for your personal or non-commercial use, or for use within your organisation. Apart from any use permitted under the Copyright Act 1968, all other rights are reserved.

Disclaimer

The information and advice provided by the Department of Fisheries website is made in good faith and is from sources believed to be reliable and accurate at the time of release onto the website. Changes in circumstances after a document is placed on the website may affect the accuracy of the information. Full disclaimer details are available at www.fish.wa.gov.au.