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| Earth on Sep 27, 2011

Lifeform of the week: Killer whales on trial

Federal hearings are underway in a case that could affect animal welfare, trainer safety and the future of marine park entertainment.

In February of 2010 Dawn Brancheau, a highly experienced trainer at SeaWorld Orlando, was pulled underwater, severely battered and ultimately drowned by a 6-ton killer whale. The attack, which occurred just after the completion of a show and in front of horrified park guests, resulted in an investigation by Occupational Safety and Health Administration (OSHA) – the federal agency designed to ensure protection of workers. OSHA issued three citations (and a $75,000 penalty) to SeaWorld including one for “willful” endangerment of its employees, a charge SeaWorld has contested. A federal hearing to settle the matter began last Monday (September 19, 2011).

This is not the first instance of a killer whale attacking a trainer and some argue that these animals are poorly suited for captivity and that it is impossible to assure the safety of any human working with them directly. In considering such allegations it is important to understand the lives of killer whales both in the wild and in captivity.

Life at sea

Wild killer whales breaching the water's surface. Image Credit: U.S. National Oceanic and Atmospheric Administration.

Killer whales, or ocras, are the largest member of the dolphin family, with males of the species reaching up to 12,000 pounds. Females, though smaller, still weigh in at an impressive 6,000 to 8,000 pounds. They travel in groups know as “pods”, sometimes covering distances of as much as 100 miles in a single day, and are found throughout all the world’s oceans. While they tend to favor cold coastal waters, these animals also inhabit warm equatorial regions and the open sea. There are three genetically and behaviorally distinct types of ocras: resident – which live in larger pods and specialize in hunting fish, transient – which eat marine mammals and roam over greater distances, and the little-studied offshore population.

Killer whales navigating their natural habitat. Image Credit: Christopher Michel.

Female orcas reach sexual maturity between six and ten years of age, but do not reproduce until they reach 14 or 15 years. The gestation period is nearly a year and a half and yields a single calf. Births are separated by 5 or more years and females usually stop breeding around age 40 (still only middle age for an animal with a life expectancy of 50-60 years) Because single pods can contains multiple generations, older females are on hand to aid in the care of new calves and mentor first time mothers.

An orca engaging in "skyhopping", a more prolonged surfacing behavior. Image Credit: Jaime Ramos, U.S. Antarctic Program NSF.

As with their dolphin cousins, killer whales are highly intelligent and social animals. Orca pods are complex social structures, each pod with its own distinct dialect of vocalizations. These sounds are also used for hunting, much like the sonar of bats. Like parenting, hunting skills are also passed on to the younger generation.

As fearsome top predators, killer whales were long assumed to be dangerous to humans. It was not until the mid 20th century that the two species began their surprising and often troubled relationship.

Life at SeaWorld

Prior to the 1960’s few people had seriously considered keeping a marine animal as large as a killer whale in captivity, much less teaching it to perform tricks in front of an audience. This changed in 1965 when Seattle Marine Aquarium owner Ted Griffin paid British Columbia fishermen – who had accidentally snared the animal in one of their nets – $8000 for the privilege of transporting a 22-foot male orca back to the aquarium, where he was finally able to fulfill his childhood dream of riding a killer whale. Crowds were enthusiastic to see Griffin and his trained killer whale (named Namu for the British Columbia town where it was inadvertently captured) and soon enough the presence of friendly, adorable performing orcas became an essential part of aquarium entertainment.

But the lives of captive orcas are profoundly unlike those of their wild counterparts and many animal welfare advocates argue that they are not well suited for being housed in aquariums. As you can imagine, even the most extravagant aquarium cannot begin to approach the range experienced by a wild orca. Captive orcas spend less time swimming and more time at the surface, which may contribute to their higher rate of dorsal fin collapse. Fairly rare in the wild, this condition affects well over half of captive males.

The collapsed dorsal fin can be seen on this captive orca. Image Credit: Milan Boers.

Captive orcas do not hunt for food, but are instead fed thawed frozen fish by their trainers (recall that not all wild orcas specialize in eating fish). Artificial insemination allows them to be bred at younger ages. Captive killer whale mothers are sometime hopelessly incompetent in caring for their calves, a problem that may result from early breeding or lack of parental guidance from older females that would normally be provided in the pod.

Separation from normal social order can cause all manner of problems among orcas in captivity. While some are captured in the wild and thus separated from their home pod, and others are bred in captivity (the latter is becoming the more common source for aquarium orcas), all lack a socially stabilizing pod structure. Instead they are thrust together with animals with which they would not associate in the wild and must work out their social hierarchy in the crowded environment of aquarium pools. Aggression amongst pool-mates is common. In 1989 a female SeaWorld orca named Kandu bled to death in front of the audience after forcefully ramming another orca in the pre-show holding tank (a fractured jaw incurred from the collision caused the massive hemorrhaging). The animals also frequently damage their own teeth gnawing on their tanks horizontal separation bars, sometimes while lashing out at one another and sometimes just out of boredom.

Orcas are that rare animal that actually lives longer in the wild than in captivity. While they can serve as potential prey for other large marine animals during their youngest years, adult killer whales need only worry about human predators. Females can survive in the wild for over 80 years (males have shorter lifespans), but those housed in aquariums can expect only a fraction of this lifespan. Few whales have lived in captivity for longer than 20 years.

SeaWorld vs. OSHA

It is orcas’ intelligence that makes them both well suited for training and poorly suited for captivity. They learn commands and routines quickly, but they can also become bored and frustrated by the peculiar rigors of training. Critics of using killer whales in aquarium shows cite the stress of captivity as a factor in attacks on trainers. Attacks on humans by killer whales in the wild are almost unheard of, but in captivity they are becoming all too common. Part of the case against SeaWorld is that they failed to change safety protocols despite their knowledge of another fatal attack (by a different orca), on trainer Alexis Martinez in the Canary Islands, which occurred only two months prior to Dawn Brancheau’s death.*

Trainers and orcas performing in a waterwork routine. Image Credit: Stig Nygaard.

Training and performing with killer whales is divided into two categories, “waterwork” and “drywork”. In waterwork, trainers actually swim in deep water and perform various acrobatics with the orcas. This is only done with those animals deemed safe for such close interaction. But so-called drywork still involves trainers standing on a shallow ledge of knee-deep water while they conduct the killer whales in their routines and dole out rewards. It was under such conditions that Brancheau was dragged into the pool and killed by Tilikum, a wild-captured orca who had been involved in two previous fatalities† and was therefore relegated to performing only in drywork routines (and only with experienced trainers). Aside from these regulations, SeaWorld’s safeguards to protect trainers were mostly in the form of teaching them how to spot warning signs of impending orca aggression.

Part of last week’s hearings were devoted to determining how exactly Brancheau was pulled into the pool. Initially reports stated that the orca grabbed her by her long ponytail, but SeaWorld employee Fredy Herrera testified that she appeared to have been pulled not by her hair but by her arm. This is a crucial difference. The ponytail grab would indicate a problem easily remedied by updating safety protocol; require trainers to pull their hair into buns (a rule which SeaWorld has implemented since Brancheau’s death) and everything is fine again. But if Dawn Brancheau was instead dragged into the pool by her arm, it would support OSHA’s claim that direct interactions between humans and enormous and unpredictable captive animals is inherently unsafe.

Note how large this creature is relative to the chairs in the background. Image Credit: The Lamb Family.

There is much debate over what causes captive orcas to turn against their trainers. Aquarium advocates generally explain injuries and fatalities as resulting from trainer error, blaming a misstep in judgment rather than a situation that is impossible to safely navigate every time. But others see the attacks not as accidents, but as deliberate aggression by animals that have been driven to madness through the unnatural strain of captivity. Despite such concerns, in late March of 2011, after a lengthy 13-month period of near isolation, Tilikum returned to performing on the SeaWorld stage.

The SeaWorld vs. OSHA hearings were scheduled to conclude last week, but, as is often the case with legal matters, things are running longer than expected and the case is now slated to resume in November. While the fees leveled at SeaWorld by OSHA are paltry by corporation standards, the “willful” citation – the most severe category of violations – is of greater concern. OSHA’s proposed solution to safety risk would require physical barriers between humans and orcas, making waterwork (and even drywork in its usual form) impossible. What the federal court is ultimately deciding is whether or not SeaWorld will be allowed to continue doing the shows that have made Shamu Stadium famous, those with humans directly interacting with killer whales.

* Martinez worked at Loro Parque, which is not own by SeaWorld, but has used SeaWorld trainers and protocols and has several orcas on loan from SeaWorld.

† The first of these deaths occurred in 1991 at Sealand in British Columbia when part-time trainer Keltie Byrne slipped and fell into a pool containing Tilikum and two other orcas. None of the animals were accustomed to having humans in the water. The second death occurred at SeaWorld Orlando in 1999 when a civilian, Daniel Dukes, for reasons unknown snuck into Tilikum’s tank after hours. Since nobody witnessed the incident, it is uncertain to what degree the orca contributed to this fatality, officially attributed to hypothermia and drowning.

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