Ferreira LC, Möller L, Fisher R, Thums M (2025). Assessing exposure of pygmy blue whales to existing threats to inform offshore wind farm development. Report to the National Environmental Science Program. Australian Institute of Marine Science.
Overview
The offshore renewable energy (ORE) sector is rapidly developing in Australian waters to meet the country’s carbon emission targets. However, new developments in the marine environment may pose added risk to threatened species. The pygmy blue whale (Balaenoptera musculus brevicauda) was identified as a key species by NESP Marine and Coastal Hub’s end-users for understanding potential impacts in relation to ORE developments. Pygmy blue whales are listed as Endangered and their distribution, including migration routes and foraging grounds, overlap areas subject to offshore oil and gas activities, fishing, shipping, and areas newly designated for offshore wind farm development in Australia. The level of overlap and quantification of the species exposure to existing human activities is required to understand prospects for species recovery, potential impacts and to support management regulation and risk assessments of proposed developments. We combined all available satellite tracking data for pygmy blue whales in the Eastern Indian Ocean and complemented it with other data sources (e.g., surveys, habitat models) to determine distribution. This distribution was overlaid with spatial data of pressures (e.g., shipping, fishing, oil-gas activity, environmental change) and associated threats (habitat loss, entanglement, displacement, vessel strike, underwater noise) in a cumulative exposure assessment framework. Threat exposure analysis included expert elicitation to gather expert input on the probability of exposure to a threat occurring from the spatial overlap between pygmy blue whale distribution and anthropogenic pressures, with a focus on areas undergoing offshore renewable energy development. The spatial data and maps produced provide a robust baseline that is key for the development of the new offshore renewable energy industry in Australia. The results support the need for continued collection of spatial data on pygmy blue whales to ensure the sustainable development of the offshore renewable industry in Australia in relation to this sub-species.
