Technical report on the Bottlenose dolphin (Tursiops aduncus) unusual mortality event within the Swan Canning Riverpark, June-October 2009

This technical report reviews findings from an investigation into the mortalities of six bottlenose dolphins (Tursiops aduncus) in the Swan Canning Riverpark in 2009. The report: (a) describes the epidemiology and pathology of these mortalities; (b) presents background information on the ecology of dolphins in the Swan Canning Riverpark and factors known to affect dolphin health; and (c) discusses the potential role of chemical contaminants in the mortalities. These mortalities were investigated in context of dolphin deaths in the Swan Canning Riverpark prior to 2009 and a series of mortalities of dolphins in the Bunbury area between 2008-10, as well as marine mammal mortality events in other locations

Indo-Pacific bottlenose dolphins (Tursiops aduncus) in the Swan-Canning Estuary (Perth, WA): ecology, status, and future research.

From October 2001 to June 2003 we photo-identified 35 Indo-Pacific bottlenose dolphins (Tursiops aduncus) within the Swan-Canning Estuary in Perth, Western Australia (n = 223 survey days). Analyses of occupancy, ranging, and association patterns identified two main groupings: (a) transient - dolphins sighted less than six times generally near the estuary mouth (n = 13, 37.1%) and (b) resident - dolphins consistently observed (n > 23 sightings) throughout the estuary and in association with each other (n = 18, 51.4%). The current status of dolphins in the estuary is not known. Low-level monitoring (n = 17 survey days) in 2008-9 re-sighted nine (50%) of the 2001-3 residents, while the carcasses of two (11.1%) were recovered in 2006 and 2009, one (5.6%) was presumed dead in 2002, and the status of the other six (33.3%) is not known. The deaths of six dolphins within the estuary in 2009 raised concerns about the long-term conservation of dolphins in the estuary and emphasised the need for new research. As part of a broader study of dolphins in the metropolitan waters of Perth, from June 2011 we will be conducting systematic boat-based surveys using belt transects coupled with individual focal follows within the estuary and adjacent coastal waters. This research has several objectives: (1) estimate dolphin abundance across the study area using photo-identification and mark-recapture methods; (2) determine residency and ranging patterns for individuals in order to better understand site fidelity and population structure; (3) determine habitat use patterns through habitat modelling; and (4) collect behavioural, environmental, and epidemiological data related to interactions with human activities and dolphin health (e.g. entanglements, epidermal diseases)

Data Descriptor: Underwater recordings of the whistles of bottlenose dolphins in Fremantle Inner Harbour, Western Australia

© The Author(s) 2017. Dolphins use frequency-modulated whistles for a variety of social functions. Whistles vary in their characteristics according to context, such as activity state, group size, group composition, geographic location, and ambient noise levels. Therefore, comparison of whistle characteristics can be used to address numerous research questions regarding dolphin populations and behaviour. However, logistical and economic constraints on dolphin research have resulted in data collection biases, inconsistent analytical approaches, and knowledge gaps. This Data Descriptor presents an acoustic dataset of bottlenose dolphin (Tursiops aduncus) whistles recorded in the Fremantle Inner Harbour, Western Australia. Data were collected using an autonomous recorder and analysed using a range of acoustic measurements. Acoustic data review identified 336 whistles, which were subsequently measured for six key characteristics using Raven Pro software. Of these, 164 'high-quality' whistles were manually measured to provide an additional five acoustic characteristics. Digital files of individual whistles and corresponding measurements make this dataset available to researchers to address future questions regarding variations within and between dolphin communities