Experimental modeling of large whale entanglement injuries

The abrasive impact of commercial fishing gear on right whale fluke tissue was modeled using a reciprocating load generator. A line passing over the leading edge of a fluke specimen was fixed at one end while the other end was loaded in an oscillatory manner. A 24-h abrasion test using an accelerated loading rate of 60 cycles/min and a 9.0-kg load on the fixed end of the most abrasive line tested (old sink line) was used to simulate a whale swimming 2 m/s towing four standard lobster buoys for five days. A tension load of 267 N was generated on the oscillatory side of the fluke. The test line failed to break the skin on the fluke but, instead, produced a compression furrow (maximum depth 0.31 cm) that closely resembled marks found on stranded right (Eubalaena glacialis) and humpback (Megaptera novaeangliae) whales. Different line types (float vs. sink) and ages of rope (new vs. old) produced furrows of varying depths and appearances. Further tests characterizing whale skin/fishing line interactions will provide a better understanding of the mechanisms that govern entanglement injuries and provide a framework for better forensic analysis and interpretation of gear-related injuries observed in large whales.