Photo by Ken Balcomb, Center for Whale Research, taken Feb. 6, 2009. The male in the foreground is L73, Male born 1986 to L5 (Tanya), missing May 2010 (age 24).

The debates about whether it's safe for Tokitae to return home tended to boil down to a belief that she was too old, been captive too long, and wasn't strong enough to be transported to the Salish Sea in NW Washington, where she was born and yes, raised by her elders. The Seaquarium took every opportunity to repeat the claim that she was "geriatric." But was she really so old?

According to the documentary Blackfish: "We knew by 1980, after a half a dozen years of research, that they [killer whales] live equivalent to human life spans."

The natural lifespans of orcas is one of the big questions that scientific studies haven't answered definitively. Only a few populations have been studied thoroughly and long enough to make those assessments, and the only population in which every individual is documented each year for decades using photo-ID (best way to survey them) has been the Southern Resident Community, the same orcas that have been heavily impacted by shootings, captures, toxins, anthropogenic noise, and most disastrously, salmon scarcity. Their average lifespans have been skewed and shortened for the past several decades.

But how long do orcas in the ocean live on average? Different methods exist for estimating the life spans of killer whales. The scientific community does not yet fully agree on this topic.

A 2005 paper by Olesiuk, Ellis and Ford listed the following life expectancies:

“46 years for Northern Resident females from 1973 to 1996 and 30 years from 1996 to 2004; 50 years for Southern and Northern Resident combined females from 1973 to 1987; 39 years for Southern Alaska Resident females from 1984 to 2001; 31 years for Northern Resident males from 1973 to 1996 and 19 years from 1996 to 2004; 29 years for Southern and Northern Resident combined males from 1973 to 1987; and 31 years for Southern Alaska Resident males from 1984 to 2001.” If that seems complicated, it's because it is. There are many factors and variables, especially in the only populations known well enough to arrive at those estimates.

The 2005 paper is the best summary of orca lifespans to date with hard data. One important caveat however, is that those data are primarily from the Southern Resident Community, a population that was quite likely significantly culled by random shootings prior to the start of the field studies. The estimates in Olesiuk et al. are based on observations beginning in 1973, and mortalities from shootings. Olesiuk et al, p. 4: "...it is possible substantial numbers may have been injured or killed opportunistically by fishermen, fisheries personnel, and sportsmen during an era of widespread predator control. Bullet wounds were evident in up to 25% of the animals taken during the live-capture fishery in the 1960s and early 1970s (Keyes cited in Hoyt 1981)."

And of course the capture episodes between 1965 and 1976, primarily targeting Southern Resident orcas, removed a cohort of young from the community, disrupting family cohesion and skewing average ages toward older whales for decades.

There are some rather astounding parallels in the phases of life for orcas and humans.

A 2012 paper by Emma Foster et al. describes something briefly discussed in the 2005 paper: female reproductive senescense, or menopause. A striking similarity between humans and orcas comes clear in the female post-reproductive lifespans.

Orcas and humans (and pilot whales) are the only mammals known to science (so far) to exhibit menopause. For both humans and orcas, females are reproductive for about 25 years until around 40 years of age, but often live 3 or 4 decades after their last offspring is born. In natural orca communities, the first calf is born when the mother is about 14-15 years old. Most human females are capable of having their first baby at about that age.

We don't have definite birth years for the older orca females, but some were post-reproductive - over 40 years old - when the photo-ID studies began in 1973, and have survived 3 or 4 decades since then. That is roughly equivalent to human life spans. Olesiuk, et al., p. 33: “Most of the females that were in their teens when our study began 3 decades ago, are still alive today. Indeed, several of the females that were post-reproductive, suggesting they were at least in their 30s or 40s when the study began, are still alive.”

Male maturation rates are also very similar for humans and orcas, beginning in early to mid-teens with full maturity in late teens. This indicates that full male lifespans in undisturbed populations may also be similar.

Many more females live into in their 80s and 90s or more, and males into their 60s and 70s or more, about equivalent to human lifespans. It's entirely possible they could have even longer lifespans.