Orca update: Why do boats matter and what can we do about it?

The Governor’s Orca Emergency Response package, currently being debated in the state legislature, includes bills to reduce vessel noise and disturbance (HB 1580/SB 5577). The Seattle Aquarium has recently been to Olympia to testify in support of this legislation.

The science shows that all vessels—from large ships and ferries to small recreational boats and even kayaks—can impact the orcas both from the noise they make and disturbance from their presence. But there are tangible things that we can do right now to manage these impacts in ways that will have an immediate benefit for the endangered southern resident orcas.

Boats surrounding an orca on the southern end of San Juan Island.
Boats surrounding an orca on the southern end of San Juan Island.

 

Underwater boat noise makes it hard for orcas to echolocate to find the Chinook salmon that are the mainstay of their diet. It also makes it harder for them to communicate with each other; this is thought to affect their ability to share information about where they are finding fish. Vessel noise can also cause stress in whales and dolphins.

The presence of boats—even quiet ones—also changes orca behavior in ways that can make them spend more energy, such as making them hurry to avoid boats instead of pausing to eat.

 

Impacts of boats within 400 meters of the orcas. Figure adapted from Lusseau et al. 2009.
Impacts of boats within 400 meters of the orcas. Figure adapted from Lusseau et al. 2009.

 

 

Data from Seely et al. 2017.
Data from Seely et al. 2017.

 

The number, proximity and speed of boats all contribute to the level of disturbance and amount of noise affecting the orcas. The proposed legislation therefore includes a speed limit and wider buffer around them, and a permit system for whale-watching that could cap the number of commercial boats around the southern residents at any given time.

These changes will help the orcas echolocate to find the scarce salmon, communicate with each other, and be able to spend more time and energy foraging.

Take action! If you’d like to lend your voice on this important issue, email your legislator today or call the toll-free legislative hotline at 1-800-562-6000 and ask them to support House Bill 1580 and Senate Bill 5577 and give the orcas both more space and quieter waters.

You can also read more about the orcas here, and learn about what hydrophones can pick up in terms of orca sounds and underwater boat noise in this KING 5 interview with Scott Viers, or join our list to receive the latest news on policy & advocacy. 

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