Bottlenose dolphins - Koombana Bay: Questions

BOTTLENOSE DOLPHINS — KOOMBANA BAY
978. Hon LYNN MacLAREN to the minister representing the Minister for Environment:
(1) What was the last reported population figure for bottlenose dolphins in Koombana Bay?
(2) How many bottlenose dolphins from Koombana Bay have reportedly died since 2006?
(3) How many of these deaths have been attributed to boating activities?
(4) How far is the proposed marina development at Koombana Bay from the dolphin birthing site?
(5) Can the minister identify the threats to dolphins in near-shore environments?
(6) Does the minister agree that research to combine a spatial understanding of Koombana Bay dolphin population and human use of the area is required in order to conduct a risk assessment before the marina project proceeds?
(7) What conservation methods will be implemented to preserve the dolphins and their birthing site?


Hon HELEN MORTON replied:
I thank the member for some notice of the question.
(1) A study carried out through Murdoch University found the population of bottlenose dolphins inhabiting Bunbury coastal and inland waters—including Koombana Bay, Leschenault Inlet estuary and the inner and outer harbour—to vary seasonally from 63 to 139. Ongoing research is being conducted by PhD students at Murdoch University.
(2) Mortalities recorded from Bunbury coastal and inshore waters—not confined to Koombana Bay are: one in 2007; one in 2008; five in 2009; four in 2010; two in 2011; and one in 2013.
(3) One in January 2010.
(4) There is no birthing site in Koombana Bay; however the inner waters of Koombana Bay, Bunbury harbour and the Leschenault Inlet estuary are considered important breeding and nursery grounds for bottlenose dolphins.
(5) The bottlenose dolphin is a common species that inhabits near-shore environments. The main threats in the near-shore environment include boats and vessel traffic, marine debris and environmental pollutants.
(6) Existing data can be used for this purpose from the research group at Murdoch University and at the Department of Parks and Wildlife.
(7) Several options have been raised for consideration, including boating or speed restrictions in areas of high dolphin use, particularly known nursery areas; an education program on awareness of dolphins in the Bunbury area and importance of clean waterways; an increase in community awareness to encourage responsible interactions with dolphins and compliance with regulations to protect dolphins; and continued monitoring of the dolphin population to identify changes in population demographics or habitat use based on anthropogenic activities.