Boating with Whales-What Depth?

Image taken under NOAA Fisheries Research Permit 21321

Research in Hawai`i has found that whales are most frequently found in waters with a depth of 100 fathoms or less. So, during whale season if you are transiting waters at depths of 100 fathoms or less, you have a higher chance of encountering and colliding with a whale, which may injure it, cause hull damage or sinking, and injure passengers aboard your vessel.

So what preventive measures can you take to reduce the chances of a collision?

  • Vessels should travel at a speed of 15 knots or less, or at minimal planning speed, when in depths of 100 fathoms or less during the humpback whale season.
  • Vessels should post a dedicated lookout to help spot whales.


1. What TIME of Year?

2. What DEPTH?

3. What SPEED?


5. What’s the SOLUTION?


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