*Draft*Movement behaviours and habitat usage of West Kimberley dugongs: A community based approach

Brief description

Project 0809/14: Movement behaviours and habitat usage of West Kimberley dugongs: A community based approach Four dugong tagged in Beagle Bay 16-19 July 2009 Western Australia. Results showed a high degree of fidelity to Beagle Bay, but one dugong travelled 500 km south. Dugong in the West Kimberley were tagged for this study in two locations on the Dampier Peninsula. These animals showed a variety of foraging behaviours and movement patterns, in some ways similar to other populations of dugong studied throughout Australia. Dugong were observed to move over large distances (100s of kms) but also to exhibit a high level of foraging site fidelity. Foraging ranges were similar in size to other areas around Australia but appeared to be smaller within the Beagle Bay area than for other places along the Dampier Peninsula. Dugong in this area appear to travel along the sea bottom by preference and combine periods of foraging in restricted areas in between periods of migration/movement. Dugong utilised shallow water habitats (< 5metres) throughout the study area, but were observed to dive to maximum depths of approximately 20 metres. The tide and diel periods exerted a strong influence on the micro-scale patterns of habitat use, with use of the inter-tidal seagrass habitats only occurring at high waters periods during the night. These micro-scale patterns of habitat use may be influenced by avoidance of daytime predators, including traditional indigenous hunters. There was no systematic migration of animals from one area to another, however this may be due to the limited period of the deployments throughout the seasons. This study identified important foraging habitat within embayments but also along the open coastal margin of the Dampier Peninsula, suggesting that these habitats are important conservation areas for dugong. Further research to better understand the patterns of habitat use, the distribution of foraging effort and the patterns of seagrass distribution are needed to help design effective conservation programmes in this area. Studies designed to determine the seasonal migration patterns of this metapopulation of dugong are also important to understanding the links between populations of dugong throughout the north-west of WA. These data will also contribute to the development of community-led management plans for the sustainable use of dugong and the development of future research programmes to address knowledge gaps to achieve sustainable hunting outcomes. These data area also valuable in contributing to the knowledge and understanding of the likely impacts of large-scale industrial developments throughout areas identified as foraging locations for dugong in the West Kimberley.