Avoidance of mussel farms by dusky dolphins (Lagenorhynchus obscurus) in New Zealand

作者：Pearson H C^*; Vaughn Hirshorn R L; Srinivasan M; Wuersig B

来源：New Zealand Journal of Marine and Freshwater Research, 2012, 46(4): 567-574.

DOI：10.1080/00288330.2012.712977

• aquaculture
• behaviour
• cetacean
• conservation
• dusky dolphin
• foraging
• Lagenorhynchus obscurus
• mussel farm
• New Zealand

We describe fine-scale interactions between dusky dolphins and mussel farms in Admiralty Bay, New Zealand. We examined dusky dolphin presence in nearshore mussel farms, coordinated feeding behaviours in and near mussel farms, and long-term changes in regional population abundance. Sampling methods included boat-based surveys, focal follows, underwater observations, and photo-identification. Correcting for area, dusky dolphins spent significantly less time inside mussel farms versus outside mussel farms and other nearshore areas (both P<0.001). Prey balls entered or moved adjacent to mussel farms during 2/52 feeding bouts, after which dusky dolphin feeding behaviour ceased. Total estimated abundance during winter 20052006 was 712 (95% CI: 5111134) with a declining trend in annual abundance after 2003. Results suggest that: (1) dusky dolphins rarely use mussel farms; (2) mussel farms may hinder coordinated feeding strategies; and (3) the number of dusky dolphins using this foraging habitat varies between years and may be declining.

• 出版日期2012