Well-Known Orca Who Died Had Shocking Level of Toxins in Her Body

Last year, a group of orcas living in the UK endured a heartbreaking tragedy after one of their well-known members was found dead. Now, more troubling news has followed: this week, scientists announced that she had a shocking level of toxic pollutants in her body.

Lulu, the orca who died, was a member of a small resident population of orcas living off the coast of Scotland who are known as the West Coast Community.

In early January, her body was sadly discovered on the shore of Scotland’s Isle of Tiree. It wasn’t clear whether she stranded before or after she died, but scientists from the Scottish Marine Animal Strandings Scheme determined that she had most likely drowned as a result of entanglement.

They wrote at the time, “There were deep, granulating wounds … consistent with a rope wrapping around the tail and trailing behind the animal, probably still attached to something at the other end. This would have made normal swimming very difficult, and we suspect the animal had been entangled for several days. She hadn’t fed recently but had swallowed a large amount of seawater, most likely as she eventually succumbed to the entanglement and drowned.”

Scientists found that Lulu had “shocking levels” of polychlorinated biphenyls (PCBs) in her system, which were high enough to make her one of the most contaminated animals ever recorded.

These findings paint a grim picture for the future of these orcas, and for other marine animals.

“The levels of PCB contamination in Lulu were incredibly high, surprisingly so,” Dr. Andrew Brownlow, head of the Scottish Marine Animal Stranding Scheme and veterinary pathologist at Scotland’s Rural College, told BBC News. “They were 20 times higher than the safe level that we would expect for cetaceans to be able to manage.”

Even though they were banned decades ago, PCBs are still extremely persistent in the environment and have continued to make their way into marine ecosystems, even finding their way to the deepest parts of the ocean. They make their way through the marine food web, accumulating at high levels in top predators where they pose a serious risk to their health.

Lulu was estimated to be about 20-years-old when she died, but despite being mature enough, scientists also found she never had a calf. Alarmingly, no calves have been seen among her family members for more than 20 years, which has raised concerns that they are going to go extinct. With as few as eight members left, Lulu’s death has made that even more likely.

The presence of PCBs is suspected of playing a role in the infertility among this group, and may also have contributed to Lulu’s death.

“It is potentially plausible that there was some effect of the PCBs that was in some way debilitating her so she wasn’t strong enough or even aware enough to deal with this entanglement (in fishing line),” added Brownlow. “We very rarely see entanglement in killer whales – actually this is one of the first cases we have documented.”

Her death has raised more questions and worries about how marine animals are going to fare carrying these toxic burdens, among the other threats they face, and about whether we’ll take meaningful action to keep safe from yet more pollution in their environments.

Our actions may have doomed the West Coast Community, but it remains to be seen whether we’ll act quickly enough to save others, including our own beloved Southern Resident Killer Whales.

http://www.care2.com/causes/well-known-orca-who-died-had-shocking-level-of-toxins-in-her-body.html