Orcas and fishermen working together
15 October 2009 - 6:35pm
A massive pod of up to 50 killer whales has been filmed for the first time off the coast of Scotland by a BBC crew.
The BBC reports that Gordon Buchanan, presenter of BBC Autumnwatch, filmed the group from a fishing boat in the North Sea.
As the largest member of the dolphin family, killer whales are known for their intelligence and range of hunting behaviours.
The pod of killer whales caught on camera belong to a family group that has developed a particular hunting strategy; following mackerel fishermen and feeding on fish that escape their nets.
The killer whales pick of any escaping mackerel and also feed off scraps as the nets are later lowered back into the water to be washed clean.
The BBC notes that 'Scientists first documented this behaviour in the 1980s and fishermen in Scotland have seen the behaviour develop since.
"They are pretty quick to cotton on, and it's something they are doing all around the world where there is a big fishery," says Mr Andy Foote of the University of Aberdeen, a marine scientist advising the BBC Autumnwatch team.
"But what's great about this one, is they aren't viewed as a pest, they are just going after mackerel that are stuck in the nets or escaping and they don't take any of the fishermen's catch," he says.
"They don't damage the nets or get stuck in the nets, there is a benefit for both parties and the fishermen are really fond of the killer whales."'
I first saw this behaviour in the mid 1990's when I travelled to Iceland for WDCS. I had the luck to travel with the Icelandic fishing fleet to observe orcas south of Iceland. Having convinced them I was not there to cause them problems, the fishermen opened up and explained that they regarded the orca as 'colleagues'. This was at a time, like now, when politicians and whalers back in Iceland were agitating to kill whales, and orcas were portrayed as 'evil fish-eating vermin'
The truth was that the fishermen would use their sonar to identify where the orca were at sea and the fishermen would then target that bit of ocean. Setting their nets (purse seine) where the orca were feeding, the fishermen stated that they would get a higher catch if they relied on the orca.
What was fascinating was that the orca would sit back and wait for the net to be partly pulled in. In what appeared to be a well planned process that the orca were fully cognizant of, the fishermen would pause to allow 'stunned' fish to fall out of the top of the net and then the orca would come into feed. The most wonderful sight was seeing a female bringing in a calf and nudging the cal towards the net to catch its first (or nearly first fish). Repeated passes were observed until the calf had successfully taken a fish, to which I could swear the mother was 'smiling'.
The rest of the pod would then come into feed. All the while, the fishermen would watch and wait until they felt the whales had had enough and then pulled their nets in. The whales would then, as one, head off to the next Icelandic fishing vessel on the horizon - a bit like finishing at one feeding station and now onto the next.
The boat I was on collected their fish and then moved on again towards where the whales were to be found to set their nets again and the whole process was repeated.
On the return trip I asked the fishermen what they felt about the political arguments that whales were eating all the fish', an argument that the Icelandic Government still makes. I remember one fisherman dismissing it as 'Reykjavik politics' and that the whales were 'their friends'.
I remember the evening ending with me watching the stunning sight of a male orca, with a six foot fin, swimming slowly past the boat, its fin so tall that it appeared to cut out the light from the moon as it passed.
Most probably one of the best nights of my career in cetacean protection.