Facts About the UK’s Last Killer Whales

A pod of Killer Whales

When it comes to marine creatures, dolphins always end up on the must-see list of wildlife enthusiasts. Truth be told, sightings and mass strandings continue to attract a lot of people in Britain. Currently, dolphin watching is a popular activity in places like Land’s End and Lundy Island.

Unknown to many, the waters around the British Isles features diverse species of resident and visiting dolphins such as the bottlenose dolphins. Other species seen in the UK include Risso’s, long-finned pilot whales and even killer whales. Yes, you read that right – there are killer whales or orcas in the UK. In fact, the last UK killer whales in Britain reside on the west coast of Scotland. The pod, initially composed of 9 dolphins, has been monitored and studied for a quarter of a century already.

What Are Killer Whales?

Despite their name, killer whales are not actually whales. They are dolphins - the largest member of this family. Their deceiving name was derived from the fact that they are able to take down enormous marine mammals like blue whales. Using their massive teeth, they hunt different animals, from sea birds and sea turtles to seals and sea lions. Orcas are on top of the food chain which means that, aside from humans, no other creatures hunt them.

Killer whales are not just fascinating because of their gigantic size and sheer might. They are also intelligent creatures, having the second-biggest brains among ocean mammals. Because of their intelligence, orcas are able to devise highly effective hunting strategies, thereby explaining why they are one of the most successful predators in the world.

Wild Orca

Additionally, they are able to establish complex family and social ties. One behaviour noted to be unique amongst orcas is that the males stay with their mothers for the rest of their lives. They only leave the group when they search for mates. A pod is the term used to refer to a group of killer whales. These pods may have as many as 40 members. Those belonging to the same pods work together in taking down bigger prey. They also help each other in raising the calves.

Orcas are found in different places around the world, both in warm and icy waters. Rarely staying in one area, pods travel to different locations. Some even travel long distances with one report saying that one pod travelled a distance of 2,000 kilometres.

Important Facts About the Last Orcas in the UK

The resident pod of orcas in the UK has eight members, four males and four females. Dubbed as the “west coast community”, this pod was initially composed of nine orcas but one died in 2016. Members of this pod have the following names: Aquarius, Comet, Floppy Fin, John Coe, Moneypenny, Nicola, Puffin and Occasus. The one that died was named Lulu.

Orca with a flopped dorsal fin

You may wonder how it’s possible to distinguish each member of the pod. Well, scientists use the coloration and identifiable marks on these orcas to distinguish them. For example, Floppy has a “flopped” fin, a condition rare in wild killer whales but common amongst those in captivity. In this condition, the dorsal fin collapsed to one side. Meanwhile, John Coe’s tail fluke is missing a large patch and has a recognisable mark on its dorsal fin. The males have dorsal fins which are about one meter longer than the females.

The exact relationship among the members of this pod is not known. However, given their matriarchal structure, experts think that the males may be the offsprings of the females. Studies reveal that the west coast community may be likely related to the Antarctic Orcas, although they still have notable differences. Compared to the Antarctic orcas, Scotland’s resident orcas are bigger by about one metre. The patches on their eyes are also slanted downwards towards the rear.

Why are their fears that the orcas on the west coast of Scotland will become extinct? Not a single new calf was born in this pod for the past 25 years. Furthermore, no other killer whale has joined the group. With this trend and with the members aging, the chance of the pod vanishing from UK’s waters is high.

Scientists have not found out why females in this pod have not been able to produce new calves. One theory is that they are already too old to reproduce. Another possible explanation is that pollution has negatively affected their reproductive success. The latter theory has been further reinforced after the tests from Lulu, the female orca who died, revealed high levels of toxic contamination.

According to reports, the levels of polychlorinated biphenyls (PCBs) in Lulu’s body were 20 times higher than the safe level. It is unclear why she had extremely high PCB levels. Though, some think that it may be a result of years of accumulation given her age, around 20 years old. With these findings, experts are now wondering if other members of the west coast community also have high contamination levels.

Killer whale with a calf

PCBs, which have been heavily used last century, have been proven to cause health problems in animals. The toxic chemicals affect the immune system and the reproductive organs. They are also known to impair the animals’ brain. Scientists think that the high levels of PCBs in Lulu’s system have drastically affected her brain, explaining why she wasn’t able to avoid getting entangled in the fishing line.

Although the use of this toxic substance has been prohibited all over the world since the 1970s, they are still found in the oceans. This is primarily because PCBs take a great deal of time to break down. There are measures which can be implemented to decontaminate affected areas; however, it costs billions. While their amounts are declining in European waters, more work must be done, especially since tons of PCB-contaminated materials are still awaiting disposal.

While the future of the west coast community may be bleak, scientists and conservationists haven’t given up on them. They still continue to monitor and study this pod to gain more knowledge about killer whales.

—

Pod of Killer Whales photo by ocat