Cognitive Processes and Pod-Dynamics of Orcinus Orca

Orcinus orca, commonly referred to as orcas or killer whales, are dominant apex predators of Earth’s marine biomes. The success of the species is highly dependent on a variety of physiological and social adaptations, not least of which is the development and structure of pods. Similar to troops made up of non-human primate species, pods consist of many related and unrelated members that work in coordination to carry out necessary functions for survival and reproduction. The success of a given pod is contingent on the ability of individuals to operate in a cohesive and mutually beneficial manner with fellow members. Complex hierarchical structures as well as habitual communication, learning, and other processes dictate the functionality and ultimate well-being of the social group and either promote or inhibit group prosperity. Additionally, examinations into the behaviors of orcas removed from pods, such as in captivity, can offer crucial insight into the cognitive machinery that drives the actions behind this formidable predator.

One of the most essential features of any social species is the ability to communicate effectively within populations. As with all cetaceans, species communication in orcas is primarily performed via a catalogue of various acoustic noises, including echolocation clicks, burst-pulse sounds, and whistles. The primary functions of such behavior involve group cohesion, mating, offspring care, migration, and hunting2 The significance of effective communication within the pod is most strongly represented by the necessary cooperation between individual members that allow for these actions to be carried out. Hunting is a prime example of this concept, as orcas display some of the most complex and synchronized group-actions when it comes to food acquisition. Although initial assumptions promoted the concept of orcas continuing the use of acoustics while hunting prey, the findings of a 2011 study by Dr. Volker Beecke refuted that idea in favor of something completely opposite. Dr. Beecke’s results concluded that the orcas actually fell silent while in pursuit of certain prey, specifically other aquatic mammals, due to the probability that the prey would be alarmed and escape prior to the orcas’ arrival.

Instead they spread out across a wide expanse of water, presumably out of sight from each other, and closed in around the prey. Dr. Beecke concluded that this behavior must be the result of a form of “rehearsal” or preemptive planning prior to the moment that vocal communication is discontinued. These finding are significant due to the potential implication that orcas possess the cognitive ability to not only plan their own future actions, but to collectively do this as a cohesive and synchronized hunting unit. Future-planning is a cognitive process that is reserved for a select number of species, including humans, primates, and raven, that often is found concurrently with the ability to either make or use tools. However, the lack of tool use by orcas in most hunting situations indicates an advanced process of planning that is independent of necessity to know how to use tools, but rather is used as a means to perform group coordinated tasks.

Orcas, however, are not limited to a single, cognitively-engrained technique for hunting. Research suggests that killer whales exhibit different methods for hunting mammals, as described above, as they do for hunting fish. Whereas a stealthy, large-group-oriented coordinated effort is favored for the more massive and acoustically aware aquatic mammals7, a noisier and more fragmented approach is taken toward schools of fish. One study of Puget Sound killer whales recorded the grouping of various members within a single pod to create numerous fractions that pursued salmon schools independently of one another. This behavior was particularly prevalent when hunting fish near the ocean’s surface, where 93% of the prey were caught within 20m of the surface, and was also associated with decreased swimming velocity of the whales and also less distance between subdivisions of the pod. The research team ultimately concluded that the orcas’ behavior was indicative of recognized advantages of pod-coordination for food searching, but the small-group approach must be more effective for the actual capture of prey.

Although little can be said about the complete array of mental processes that contribute to the particular hunting of fish via this technique, it is certain that a degree of intentional decision-making occurs when assessing whether to hunt in a loud, large pod or silent subdivisions on the surface. Therefore, evidence is present that orcas my possess specific recognition skills that allow them to interpret how their potential prey behave in a hunting situation, most likely based off of previous experience with other members of the prey’s species. By extension, the presence of a well-tuned memory is apparent in killer whales that may or may not be restrained to food-recognition.

The development of communication methods is another result of pod dynamics that is essential to the function and success of the whole group. The process of learning how to communicate is a keystone development of orcas that has led to pods developing unique and differing dialects from other orca communities1. Group-specific sound repertoires are believed to aid in the strengthening of bonds was well as the structural integrity of a given pod. The development of such behavior by orcas could be linked to one of two potential explanations: either genetic, and therefore the innate, ability to produce one’s pod’s acoustics, or the ability of offspring to learn such vocals from the adults with whom they are raised and interact.

A 2014 study explored this debate through the removal of captive orca offspring from their biological parents and placing them in the presence of non-familial members of the species that were not from the same pod (since they were not in the wild). The researchers observed that over the course of 5 years from 2001 to 2006, the juvenile orcas were producing approximately 44% of the same vocal sounds as their adopted-parents. At the beginning of the experiment, the young orcas had no recorded acoustics in common with these same adopted-parents. This study heavily supports the notion that learning is very much dependent on the social interactions experienced within the pod setting, as opposed to solitary animals that rely more on life experiences and instincts to continue existence and reproduction. Therefore, the dynamics and continuation of a pod’s culture are contingent on the responsibility of offspring to properly take on observed behaviors of associated adults. The duration of the existence of a given dialect, which is known to be at least 10 years13, further accentuates the evidence of learning through observance and contact, and possibly even generational continuities in knowledge.

A recent study published in January of 2018 recognized and confirmed a fundamental aspect of orca learning that has implications for the rise of such dialects. Through tests carried out on captive killer whales, José Abramson observed that the animals exhibited a remarkable ability to reproduce various sounds that were played to them through a recording. His findings demonstrated that of the 20 words and sounds tested, the orcas were able to repeat back the sound at the level of satisfaction of the researchers or better for 16 of the words within their first 10 trials. Abramson proposed two potential explanations for this remarkable ability. The first of these is that the replication of a sound is merely a result of short-term memory storage of the projected noise, and the specific aspects of the words are never actually processed. This is essentially a reflection of the noise, rather than intentional repetition.

The other proposition of Abramson, and the one he seemingly agrees with, is that the orcas are indeed recognizing the components of the sounds and words and making a conscious effort to replicate them back. The evidence for this is provided by the fact that they overwhelmingly succeeded in the task with statistically few errors, while converted sounds from the air and reproducing them in the water, by using an acoustic system that is dissimilar from that which they are receiving the sounds, and also by matching the tones that they hear. Overall, the important implication of Abramson’s findings is that orcas have a highly developed mechanism for mimicry, which is a crucial element of social learning. As this pertains to the duration and continuation of pod-specific dialects, the ability to effectively mimic would allow a calf to quickly understand and respond to the other members of it’s pod, significantly aiding in it’s survival and fitness. However, the side effect of such behavior is that the same dialect - or at least a close variation - gets continuously passed down through generations within a pod, lasting for more than a decade at a time.

Further evidence of observational learning processes in killer whales can be extracted from the passage of non-vocal knowledge from adult to calf. Specifically, due to the matrilineal pod structure, the majority of teaching is performed by pod female orcas while both male and female calves are the receivers of training. Essential tactics for hunting and other life skills tend to be learned through the observance of adults as they intentionally perform superficial tasks as a means of demonstration for the calf rather than to serve their own biological needs. For example, adult females have been observed intentionally beaching themselves even in areas where prey, specifically seals or sea lions, are absent. A 1990 study carried out by Christophe Guinet referred to this peculiar behavior as “social beach playing,” and subsequent observations were made of juvenile orcas mimicking the adults’ actions in this way. Additionally, Guinet notes that the majority of the adult-beaching actions were taken by non-familial pod members, as opposed to the calf’s own mother. This has significant implications for the social structure of pod-dynamics through shared teaching responsibilities and offspring brooding. Whereas it is most common in the animal kingdom for one’s own parent or parents to carry the burden of education, orcas appear to take part in alloparental care, specifically where adult females teach unrelated offspring of the pod skills that traditionally would be passed on to direct descendants.

An advanced cognitive process that is found sparsely interspersed throughout the animal kingdom is the ability to recognize oneself and information as well as visual changes of the self’s physical state or appearance. Extensive experiments have been performed on both primates and human infants to assess how one perceives its state of being in situational environments. Similar tests to those given to primates and humans have been used to determine this same ability in killer whales, namely the mirror self-recognition test. This was conducted by F. Delfour and K. Marten in 2001 on 5 captive killer whales in Marineland located in France. By making use of the mark test, in which a zinc oxide mark is created on the orcas’ heads, the researches were able to observe comparatively abnormal behavior while in front of the mirror that the researchers categorized as contingency checking, including: bubble blowing, playing with one’s fish, tongue protrusions, and rhythmic head movements. These behaviors were then equated to the primate display of rubbing at the mark or prolonged staring, which indicated recognition of the self by the orcas and their current physical appearance.

However, it is important to acknowledge that self-recognition is not indicative of self-consciousness, as orcas are adept mimics and therefore visually perceptive. Considering the relative rareness of such an ability, logic would dictate an evolutionary advantage must be contingent on this characteristic of intellectually advanced organisms. An argument could be made that recognition of one’s own spatial occupancy could play a role in the success of the pod, which in turn determines the success of the individual. Possibly due to the coordination within a pod to carry out most life functions, such as hunting, raising offspring, and navigation, having this capability might allow an orca to best perform its duties within the group by better understanding how the actions of others may implicate emotions or states of being that that orca has felt and therefore acted similarly. Contrarily, mimicry may offer a simpler explanation for this behavior, where self-recognition would allow a given killer whale to assess it’s ability to repeat another’s activities by being aware of how it’s own behavior is reflective of the other.

Given the shared trait of self-recognition amongst orcas, humans, and non-human primates, other similarities in cognitive functions between the three could offer further insight into the interworking of killer whale mental capabilities and pod dynamics. Doctoral student Yulán Úbeda and other researchers tested 24 captive orcas in a 2018 study that examined similarities between 38 personality traits within five major categories - extraversion, agreeableness, conscientiousness, dominance, and carefulness - in humans, orcas, and chimpanzees. The results of their research concluded that orcas and chimpanzees exhibited similar levels of various indicators of conscientiousness, agreeableness, and dominance. Furthermore, personality crossovers were also found between all three species in the category of extraversion. Úbeda contends that the explanation for such a convergence of personalities may lie in the shared characteristic of the three, which is social group formation and dependence.

Essentially, the higher an individual is in personality traits that make them more appealing and altruistic to the pod, troop, or other group, the more likely that they will succeed in that setting, ultimately boosting their reproductive fitness. This is especially evident in the findings that the strongest correlation between chimpanzees, humans, and orcas are found in the categories of conscientiousness, agreeableness, and extraversion. These three traits are proven to be sexually more attractive in humans when they are prominently displayed, leading one to believe that this may be true in orcas as well. Additionally, the presence of “dominance” is unsurprising due to the natural mating advantages that dominant individuals benefit from in social animal species. However, it is important to account for the captivity-factor of this experiment in this regard. By being isolated from naturally occurring pods, the presence of dominance in multiple orcas could possibly be explained by their independence from a true social group where reproductive responsibilities are more dictated by instincts and pod dynamics than zookeepers and other human caretakers. This could easily skew results, as a lack of hierarchical structuring and also confinement-induced stress may lead to individuals displaying heightened aggression or other behaviors that could be misinterpreted as dominance.

In recent decades, especially following the deaths of trainers at major corporations such as SeaWorld, a heated ethical debate has arisen over the desire to confine such massive, free-roaming aquatic mammals. Multiple studies have been published that take a deeper look into the psychological effects unnatural containment has on killer whales. The results have been used in various activist motions as leverage for the abandonment of large-animal confinement in zoos and for other human purposes. A 2016 study conducted by Robert Anderson, Robyn Waayers, and Andrew Knight explored these various impacts of confinement on the natural personality tendencies of orcas, as well as enhanced and developed traits that may be resultant from captivity and life outside of a naturally occurring pod. One of the most publicly recognized behavioral developments of captive killer whales that Anderson’s team recognized is the repeated tendency to be hyper-aggressive. Their research found that SeaWorld alone has had in its possession 65 orcas since 1964, and of those 29 have been performed an act of aggression.

Interestingly, their are significant similarities in the origins of the individuals with the most consistent acts of aggressions, where they seem to stem from 5 identified familial backgrounds. Another behavior that is universally performed by wild orcas is what Anderson identifies as “tactical deception,” which is a range of actions hat involve deceitful movements that are performed with the intention to gain an advantage over another individual or prey. An example of this is the tendency to fall silent while hunting non-mammalian prey in the wild, such as schools of salmon. Researchers observed that the tactical deception is all but nonexistent in the captive orcas studied, which could be explained by either the lack of necessity for it in a controlled environment such as SeaWorld, or possibly it is a result of cognitive alterations that have arisen due to unnatural confinement and human interaction.

Also of significance which can be extracted from the Anderson study is the ways in which the confined orcas operated and created a hierarchy within their artificial pod. There were two major outcomes of such a living scenario: expression of cooperative/altruistic behavior and also the determination of a dominant individual. Cooperative tendencies were displayed in a number of ways, specially in group-coordinated actions. One such example of this is when one individual orca, named Keiko, redistributed fish back to the trainers who were introducing him to live-fish hunting. Another time this behavior was displayed was when two other killer whales, Kasatka and Kotar, took alternating turns getting attention from a single trainer. These behaviors may actually indicate the retention of wild traits and instinct, as orcas are known to be cooperative, social organisms. The continuation of these behaviors in captivity may be the result of a desperate need for social interaction or, as determined from the “pod” observed, from the obvious establishment of Kasatka as the leader/dominant individual had occurred.

The presence of an alpha or omega in the makeup of a pod or other collection of individuals from a social species may promote these cooperative behaviors as a director may not be essential to life in captivity. Possible evidence for this is how Kasatka was able to influence another orca to give her a fish through a barrier between their cages seemingly without any vocal interactions. Furthermore, Kasatka was able to influence an unseen orca to reject a fish. Both of these display the development of a pseudo-hierarchy that, in captivity, would seem not to offer a physiological advantage for the individual. Due to this, it could be argued that these relationships and cooperation may be mechanisms for mental health and cognitive stability, which would further promote the concept that captivity causes manufactured stress that would otherwise not be experienced in wild settings.

Orca cognition is a complicated and intricate aspect of the ocean predator’s repertoire. Their ability to perform such a wide variety of tasks, such as mimicry and self-recognition, indicate a mental capacity far beyond most members of the animal kingdom. In many ways, the survival of species is dependent on the interplay of each individual’s mental capabilities, as the integrity of the orca pod very heavily depends on it. The hierarchical structure of pods and the coordinated actions of their members are all essential elements to the species’ dominance that rely on the cetacean’s unique and complex cognitive processes the make it so well suited to the vast ocean biome.