Incidental catches are reported from Newfoundland, the Mediterranean and the Atlantic coast of France. In British waters, long-finned pilot whales are accidentally caught in gillnets, purse seines and in trawl fisheries. Very few are reported taken incidentally in fisheries in the Southern Hemisphere (Reyes 1991). However, according to Bernard and Reilly (1999), there are probably more pilot whales taken incidentally than are presently documented. On the east coast of the USA, the foreign Atlantic mackerel fishery was responsible for the take of 141 pilot whales in 1988. This fishery was suspended in early May of that year as a direct result of this anomalously high take. A 1990 workshop to review mortality of cetaceans in passive nets and traps documented an annual kill of 50-100 G. melas off the Atlantic coast of France. Long-finned pilot whales are also known to be taken incidentally in trawl and gillnet fisheries in the western North Atlantic, and in swordfish driftnets in the Mediterranean (Olson and Reilly 2002).
Zerbini and Kotas (1998) reported on cetacean-fishery interactions off southern Brazil. The pelagic driftnet fishery is focused on sharks (families Sphyrnidae and Carcharinidae) and incidentally caught at least 15 Globicephala melas in 1995 and 1997. The authors conclude that the driftnet fishery may be an important cause of cetacean mortality in that region.
Although there is considerable controversy regarding the absolute level of declines, there is good evidence of large-scale reductions in many predatory fish populations (e.g., Baum et al. 2003, 2005; Sibert et al. 2006; Polacheck 2006) and over-fishing and collapse of several important “prey” fish stocks world-wide (e.g., Jackson et al. 2001). The effects of such fish population reductions and subsequent ecosystem changes on world-wide populations of long-finned pilot whales are unknown but could result in population declines. Commercial fisheries for squids are widespread in the western North Atlantic. Target species for these fisheries are squids eaten by pilot whales, again raising the possibility of prey depletion.
This species, like beaked whales, is likely to be vulnerable to loud anthropogenic sounds, such as those generated by navy sonar and seismic exploration (Cox et al. 2006).
Predicted impacts of global climate change on the marine environment may affect long-finned pilot whales, and may induce changes in the species’ range, abundance and/or migration patterns (Learmonth et al. 2006).