Study

Short-finned pilot whales (Globicephala macrorhynchus) respond to an airgun ramp-up procedure off Gabon

  • Published source details Weir C.R. (2008) Short-finned pilot whales (Globicephala macrorhynchus) respond to an airgun ramp-up procedure off Gabon. Aquatic Mammals, 34, 349-354.

Actions

This study is summarised as evidence for the following.

Action Category

Use ‘soft start’ procedures to deter marine and freshwater mammals to reduce noise exposure

Action Link
Marine and Freshwater Mammal Conservation
  1. Use ‘soft start’ procedures to deter marine and freshwater mammals to reduce noise exposure

    A study in 2008 in a pelagic area in the South Atlantic Ocean, Gabon (Weir 2008) found that during a ‘soft start’ procedure using seismic airguns, a pod of short-finned whales Globicephala macrorhynchus changed course and travelled in the opposite direction to the seismic vessel for several minutes before milling at the water surface or travelling parallel to the vessel. Prior to the ‘soft start’ procedure, a pod of 15 short-finned whales was observed travelling steadily northeast for 24 minutes towards the seismic vessel. Nine minutes after the ‘soft start’ procedure commenced, the whales changed course by 180° and travelled southeast away from the vessel. Three minutes later, the whales were observed milling at the water surface or travelling parallel to the vessel as it passed their location within 900 m. In March 2008, a seismic survey was conducted using a single airgun array (consisting of six airgun strings) towed at a depth of 8.5 m and a speed of 4–5 knots y a 90-m vessel. An automated ‘soft start’ procedure was used with additional airgun signals added every 51 seconds during a 30-minute period. The whale pod was located 900 m away when the ‘soft start’ commenced. An observer on board the survey vessel recorded the position and behaviour of the 15 whales for 24 minutes before and 30 minutes during the ‘soft start’ procedure.

    (Summarised by: Anna Berthinussen)

Output references
What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 18

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.


Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape Programme Red List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Bern wood Supporting Conservation Leaders National Biodiversity Network Sustainability Dashboard Frog Life The international journey of Conservation - Oryx British trust for ornithology Cool Farm Alliance UNEP AWFA Butterfly Conservation People trust for endangered species Vincet Wildlife Trust