Killer Whales (Orcinus orca) by Katie Everett

Meet the majestic Orca!

kteverett98 — 2020-03-31 15:42:33 UTC

Yeah, you all know who this fine fellow is. After all, they were all over the news at one point due to a certain infamous documentary (but we'll talk about that later). For now, let's focus on what else we know about our beloved killer whales.

Killer "Whales"

kteverett98 — 2020-03-31 16:09:08 UTC

Fun fact: Orcas are actually in the same family as dolphins!

More than one species of Orca?

kteverett98 — 2020-03-31 16:30:17 UTC

Recent research suggests that Orcinus orca may in fact be a species complex! Several distinct "ecotypes" have been discovered, each with their own specific behaviors, diets, and ranges.

Source: Morin PA, Archer FI, Foote AD, Vilstrup J, Allen EE, Wade P, Durban J, Parsons K, Pitman R, Li L, et al. 2010. Complete mitochondrial genome phylogeographic analysis of killer whales (Orcinus orca) indicates multiple species. Genome Research 20: 908–916.

Where do you find Orcas?

kteverett98 — 2020-03-31 16:46:47 UTC

Orcas are one of, if not the most, widely distributed mammal species (other than people, of course). They can be found throughout the world's oceans, but generally prefer cold-water areas, often close to shore where food is most abundant (with exception to one open-water ecotype). There also appear to be distinct geographical populations, such as those in the North Pacific and around South Africa.

IUCN Red List Status: Data Deficient

kteverett98 — 2020-03-31 16:56:52 UTC

This may come as a surprise, given how charismatic this species is. However, because of their wide distribution, only specific populations have been estimated, not necessarily the species as a whole. There are also large gaps in information in areas of the Indian, South Pacific, and Southern Atlantic. The most recent estimate of minimum total population size was around 50,000 individuals worldwide.

Orca Biology Crash Course!

kteverett98 — 2020-03-31 18:59:13 UTC

Note the disparity in the population size between this and what the IUCN estimated. This further emphasizes how little we truly know about the total orca population size.

What do Orcas eat?

kteverett98 — 2020-03-31 19:10:10 UTC

The name "killer" whale is a well-earned title for these apex predators. Orcas have an incredibly diverse diet, having been documented feeding on 140+ species! These can include fish, seabirds, rays, squid, penguins, seals, sharks, sea turtles, other whales, and the occasional moose. That is not to say, however, that every orca eats all of these animals. Each of the aforementioned ecotypes appears to have a specialized diet and hunting strategies. If you want to know more about the specific diets of each ecotype, you can visit:

Killer Whale vs Tiger Shark

kteverett98 — 2020-03-31 19:40:06 UTC

Killer Whale vs Sea Lions

kteverett98 — 2020-03-31 19:44:34 UTC

Pod of Killer Whales Hunt Bowhead Whale

kteverett98 — 2020-03-31 19:48:26 UTC

Social Structure of Killer Whales

kteverett98 — 2020-03-31 22:39:17 UTC

Killer whales have some of the most complex and unique social structures in the animal kingdom. It is believed that these closely knit social groups are a part of what makes them such effective pack hunters. Unlike many other animal societies, orcas are matriarchal. Their most basic social group, called the maternal group, is centered around the mother and offspring, even the adult offspring. Several closely related maternal groups, like daughters' or cousins' groups, may come together to form a pod. Pods travel together and may be anywhere from 5 to 50 individuals. Many pods may form a community and members of these communities frequently socialize with one another. These communities are also marked by a distinct lack of aggression between members. However, members of different communities rarely interact with one another. There is also a fourth social designation: the clan. Clans consist of pods that have vocalizations in common, almost as though they were speaking the same language or dialect. Belonging to different clans does not prevent socialization, however. Different pods within the same community may also have their own behaviors, such as preferred hunting strategies or ways of greeting one another.

Sources:
OrcaLab. n.d. OrcaLab RSS. Accessed 31 Mar 2020.
Understanding Orca Culture. 2011. Smithsonian.com. Smithsonian Institution. Accessed 31 Mar 2020.

Effects of Ecology on Social Behavior

kteverett98 — 2020-03-31 23:32:35 UTC

This study proposes the idea that the degree of sociality may differ with varying ecological roles. They compare the social cohesion and behaviors of Atlantic orcas that hunt mammals and those that hunt fish. They also compare these orcas against the Pacific ecotypes.

Source: Beck, S., S. Kuningas, R. Esteban, and A. D. Foote. 2011. The influence of ecology on sociality in the killer whale (Orcinus orca). Behavioral Ecology 23:246–253.

The History of Killer Whales in Captivity

kteverett98 — 2020-04-01 00:12:08 UTC

Because of their large size, high intelligence, and incredible athletic ability, orcas have become a favorite species of people everywhere. Certainly, this species was also catapulted to fame by their inclusion marine parks and shows, such as SeaWorld. However, recently concerns about the ethics and safety of these practices have emerged after a series of tragic events and the orca's poor living conditions were revealed to the public.

Blackfish

kteverett98 — 2020-04-01 01:27:37 UTC

In 2013, the documentary Blackfish came out on Netflix and dramatically changed the way many people view SeaWorld and keeping killer whales in captivity. The documentary focuses on the history of SeaWorld's orcas, the practices SeaWorld uses to train and house its orcas, and several incidents between the animals and humans, some of which resulted in deaths of trainers. The program generated a firestorm of controversy in the media over the animals' welfare and incited a great deal of backlash against SeaWorld.

Tilikum

kteverett98 — 2020-04-01 02:28:38 UTC

Tilikum the killer whale is prominently featured in the documentary, as he was responsible for the deaths of two trainers and suspected in the death of another man who was thought to have illegally entered the park after hours to swim with the orcas. Blackfish portrayed Tilikum as being driven into madness by poor living conditions.

However, not everyone agrees with the film.....

kteverett98 — 2020-04-01 02:38:28 UTC

After the release of the film, former trainers spoke out against the film, saying that the trainers interviewed in the program were inexperienced and were not involved in any of the incidents they discussed. The documentary has also been accused of editing footage and audio to sway viewers, omitting important details about SeaWorld (such as their research and education programs), and and spreading misinformation about the incidents with the orcas and the park as a whole.

SeaWorld's Response

kteverett98 — 2020-04-01 03:03:10 UTC

In response to the public's growing outcry against keeping killer whales in captivity, SeaWorld agreed to stop breeding whales for its programs. They also began to phase out their theatrical orca shows, instead replacing them with a more educational program that still showed off the animals' talents.

What is an ecotype?

kteverett98 — 2020-04-01 03:10:36 UTC

Surprisingly, different populations of orcas have fill different roles in their ecosystems. This paper explores the various ecologies of several different population across the globe.

Source: Bruyn, P. J. N. D., C. A. Tosh, and A. Terauds. 2012. Killer whale ecotypes: is there a global model? Biological Reviews 88:62–80.