Enhancing the visibility of fishing ropes to reduce right whale entanglements

Published source details Kraus S., Fasick J., Werner T. & McCarron P. (2014) Enhancing the visibility of fishing ropes to reduce right whale entanglements. National Marine Fisheries Service, Bycatch Reduction Engineering Program report.
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This study is summarised as evidence for the following.

	Action	Category
	Increase visual detectability of fishing gear for mammals Action Link

Increase visual detectability of fishing gear for mammals

A study in 2013 at a pelagic site in Cape Cod Bay, USA (Kraus et al. 2014) found that simulated ropes painted red or orange were detected by North Atlantic right whales Eubalaena glacialis at greater distances than ropes painted green but not black, and more whales collided with green ropes than the other three rope colours. Changes in the behaviour of right whales approaching the ropes occurred at greater average distances from red ropes (3.9 m) and orange ropes (4.1 m) than green ropes (1.9 m). The difference was not significant between black ropes (3 m) and the other three rope colours. More whales collided with green ropes (total seven whales) than the other three rope colours (total 2–3 whales), although the difference was not tested for statistical significance. A row of four simulated vertical ropes (spaced 25 m apart) were placed 75–100 m in front of whales travelling near the water surface. Ropes consisted of 10-foot sections of rigid PVC pipe (1-inch diameter) painted red, orange, green or black and suspended between a weight and a buoy. Whales were observed from a stationary boat. Changes in the behaviour of whales (including respiration, mouth closures, submergence times, and turning angles) within 10 m of the ropes were recorded by video 52 times during nine days in 2013. Distances were measured with a laser range finder.

(Summarised by: Anna Berthinussen)