A brief Orca Natural History backgrounder to help understand the interactions described in KinToCetaceans
By Howard Garrett, Orca Network
The up close and personal interactions with orcas described in rich detail on this site are fascinating and offer insights into how orcas think and act. About the same time, in the early 1980s, field studies on orcas that started in the mid-1970s in Washington and British Columbia were starting to reveal the outlines of demographic parameters like lifespans, maturation and reproduction rates. The data also unexpectedly outlined three distinct and separate cultural communities within the study area, each community entirely cohesive and genetically intact over thousands of generations.
The sample sizes are still limited to a few populations and not large enough to make sweeping generalizations to orcas worldwide, and the populations studied have been perturbed over the past several decades by prey depletion, captures, shootings, toxic contamination, noise pollution, and possibly naval training exercises to the extent that the data may not be applicable to other populations, but some inferences nevertheless can be made from the data.
Granting those caveats, we learned that orcas generally tend to live about as long as humans. One difference, however, is that orcas are more precocious as neonates - after about 17 months gestation - and are able to catch their own fish and vocalize in learned calls by the age of one year. Females may reach sexual maturity by about age 6 or 7, but delay their first pregnancy until they are about 14 years old. This delayed reproduction is apparently to accord with cultural traditions, as evidenced by repeated births in captivity at ages of 7 to 8 years. Offspring (in free-ranging populations) are born approximately every 3 to 7 years from about age 14 to age 40, after which females often live up to four or five or more post-reproductive decades. Humans and orcas are the only known mammals in which females typically live several decades past their reproductive years. 
Male orcas don't appear to live as long as females. In the populations studied males have averaged about 30 years
longevity, but at least one male, (J1 Ruffles) lived to about 60 according to photographic evidence. Males reach adult size, including full dorsal fin growth, at about 20 or more years of age, indicating the potential for longevity greater than thirty years. One explanation for the lower longevity for males in the populations studied is that they have been more severely impacted by endocrine-disrupting organochlorine contaminants, such as PCBs, that continue to accumulate to ever more dangerous levels throughout their lives, whereas females transfer most their contaminants into their young in early adulthood. Another possible cause for lower male lifespans is that for male offspring ≤30 years old, there is a 3.1-fold increase in mortality risk in the year after their mother’s death. 
In some orca communities the offspring of both sexes remain within vocal range of their mother throughout their lives. In other populations some offspring, both male and female, may disperse beyond vocal range of their matriline, and join up with other groups within the community, although those offspring may later rejoin their mothers, at least temporarily. In other populations a more fission-fusion pattern has been observed, in which individuals tend to move from group to
Orcas worldwide are known to employ cooperative hunting strategies, and are known to share their food, regardless of the preferred prey.
Along with these demographic and natural history parameters, some astounding discoveries began to emerge in the early 1980s about social and family cohesion and communication systems. In 1973 Dr. Mike Bigg pioneered a new method for conducting field studies, called photo-identification, which revealed that three completely distinct types of
orcas inhabit the same waters, providing the first hint of cultural capabilities not found in any other wildlife except possibly a few other cetacean species.
In 2001 these studies were included with studies on other cetaceans to arrive at a new synthesis presented in a paper called Culture in Whales and Dolphins, by Luke Rendell and Hal Whitehead . The authors boldly announced that "The complex and stable vocal and behavioral cultures of sympatric groups of killer whales (Orcinus orca) appear to have no parallel outside humans and represent an independent evolution of cultural faculties." That's quite a statement, and a clear indication that orcas and humans are in a class by themselves, unlike any other known animal, in their demonstrated capacity to develop culturally-derived behavior patterns. No other animal outside humans live as members of traditional cultures that determine their diets, mating, social systems, communications, etc.
This cultural capacity is fundamental to understanding the full range of orca behavior. Science has been teaching us about the cognitive abilities and intelligence of a wide range of animals in recent years, but orcas rise above all others to a level that is "parallel" with humans. Everything we see and learn about orcas now has to be filtered through the prism of their capacity for creating cultures that guide and shape their behavior, including their diets, mating patterns, social systems and vocalizations. Their actions are not hard-wired like simple genetically determined instincts. Nor do orcas behave according to a Pavlovian stimulus-response mechanism, or even learned habituation or conditioned behavior. Rather, we're seeing self-aware, creative, cognitive processing with every move they make. As the demographic field
studies and abundant observations have shown, their highly self-conscious activities tend to be intensely oriented toward social interactions.
Rendell and Whitehead's landmark paper has helped guide fieldwork throughout the world's oceans ever since, informing expeditions to the Antarctic, the North and South Atlantic, the Indian Ocean, and North and South Pacific that have described a wide range of orca cultures, each with its own diet, social system, call vocabulary and genetic makeup due to cultural, and not geographic, separation, thus validating the premise of Culture in Whales and Dolphins. 
Researchers still don't quite know how to define or name the subjects of their studies, however, and are now struggling with taxonomic systems. Some want to split the Orcinus orca into four or more new species , while others say they are still just one species, albeit a very complex one. The term "ecotype" is now the popular term to describe orca cultures, but it lumps all communities of similar cultures, such as fish-eating "residents" or mammal-eating "transients," and glosses over the fact that within these classifications there are several distinctly different populations, each with its own unique call system, travel patterns, genetic makeup, etc. and none interacting in any way with any other. The term also implies that the distinctions that differentiate the groups are derived from geographical or ecological variables, ignoring the essentially cultural development of behavioral traditions that define and ultimately genetically isolate each community.
Regardless of the words used to describe them, abundant field studies have identified and described several dozen distinct communities throughout the world's oceans, each one maintaining cultural traditions that prescribe their diet, social system, mating and reproductive rules, travel patterns and rituals. But there's still something missing that's vitally important. We don't yet have any discussion about how they do it. Rendell and Whitehead were upfront about not wanting to address that question. In Culture in Whales and Dolphins they say: "Human culture is intimately linked to both language and symbolism, but there is currently no empirical basis for discussing the role or non-role of language and symbolism in cetacean culture.” They concede that: “...understanding process (cultural transmission) is crucial to our understanding of the product (culture)” but that: “...no attempt is made to deduce what particular form of social learning underlies the observed patterns” and, just to make sure we understand their position: “…we know virtually nothing about the actual learning mechanisms cetaceans employ.” But they invite others to seek answers to these questions: "We hope to stimulate both discussion and research on culture in these animals."
So let's see if we can have that discussion on these pages. How do orcas learn from one another, and how do they learn from, and teach or train, the humans they come in contact with? Orcas seem to behave differently toward humans than they do toward other animals, seemingly often making intense eye contact and devising structured interactions. What are they perceiving and processing as they interact? Humans look for and build meanings in their relationships and in most experiences, always attuned to responses and intentions from others as they continually construct and define their sense of self and overall realities within their social networks. Are orcas doing something similar? Are they probing for responses and shaping their relationships when they meet up with humans?
 E. A. Foster, et al., Adaptive Prolonged Postreproductive Life Span in Killer Whales
(2012), Science Vol. 337.
 L. Rendell, and Hal Whitehead, (2001) Culture in whales and dolphins. Behav. Brain. Sci. v24(2): 309-382.
 See Orca of the World (2012) (http://bdmlr-orcaaware.blogspot.com/2012/09/orca-of-world.html)
 P. Morin, et al., Complete mitochondrial genome phylogeographic analysis of killer whales (Orcinus orca) indicates multiple species. Genome Research April 2010, 20 (4)