Pasifik Kuzeybatısı Katil Balinaları Nesiller Boyu Aktarılan Kendi Lehçeleriyle Konuşuyor

Off the coast of the Pasifik Kuzeybatısı, the southern resident killer whales (orca) living in the waters of Washington eyaleti and British Columbia have a unique vocal repertoire consisting of their own distinct clicks, whistles, and pulsed calls. By listening to them for decades, researchers can usually determine exactly which family (pod) a nearby group belongs to from the shapes and sequences on a spectrogram. Consisting of three main pods named J, K, and L, this community harbors very different social and cultural traditions within itself, even though they swim in the same inland waters alongside other killer whale species. Scientists have long observed that the vocal repertoire possessed by these whales is passed down through generations and that the pods build completely distinct vocal cultures from one another. This natural and complex structure, which closely resembles human dialects or languages, is a striking example of the high intelligence of marine creatures.

Systematic recording studies initiated by Canadian biologist John Ford in the late 1970s have revolutionized the understanding of how these whales communicate among themselves. By comparing thousands of vocalizations, Ford proved that resident pods use extremely limited and repetitive repertoires of pulsed calls. The scientist used the term 'dialect' to describe these repertoires, but this does not mean that killer whales possess a spoken language like humans. Instead, he demonstrated that these calls possess characteristics that are learnable, group-specific, and distinct enough to distinguish families from one another. Over time, some pods have been observed to share certain call types among themselves, a situation that suggested they possess a social or cultural background and led to the emergence of the concept of acoustic clans.

The Bigg's killer whales, which share the same waters as the southern resident killer whales, coexist as two ecotypes with completely different ecological and social lives. Resident whales show a great dependence on Chinook salmon in particular and generally communicate quite vocally while foraging or traveling. In contrast, Bigg's killer whales, which hunt marine mammals, remain very silent during hunting because they are aware that their prey, such as seals, sea lions, and dolphins, could hear them. When they successfully catch their prey or engage in social interactions, their vocal communication increases. Although the habitats of these two groups overlap, the fact that they never form mixed social groups with each other demonstrates that they are part of a deep ecological divergence, including different prey species, hunting behaviors, and family structures.

According to the NOAA Balıkçılık kurumu, killer whale calves do not know these pulsed calls innately; rather, these sounds are learned and culturally transmitted from generation to generation. A calf grows up among the sounds produced by its mother, siblings, aunts, and grandmother, and gradually adopts its family's repertoire through these sounds it is constantly exposed to. Although scientists have documented this early vocal development in calves in detail, it is not scientifically possible to speak of a general timeline in which each whale learns its dialect perfectly on a specific birthday. What is important is not their chronological age, but rather the calves acquiring these social sounds by imitating the whales around them and developing their vocal control. In other words, a calf is not born with the repertoire of the J, K, or L family; it gains its family's cultural acoustic identity over time by listening to its social environment.

The ability of scientists to associate these calls with specific pods is based on the individual identification and tracking of killer whales in the region since the 1970s. Canadian researcher Michael Bigg pioneered the photographic identification method using the shape of each whale's dorsal fin and the saddle patch behind it. Thanks to this method, researchers have been able to individually recognize legendary whales like J2 over the years and map out their family trees in detail. Comparing old records as family members pass by underwater microphones (hydrophones) has made the Pasifik Kuzeybatısı one of the best-documented examples of vocal culture outside of humans. While the rapidly clicks made by killer whales are used for echolocation, whistle-like tones are used to establish social contact, and pulsed calls function as the main elements that determine family dialects.