A1 Pod

A1 pod is the name given to one of the best known killer whale families in British Columbia. It currently consists of 3 matrilines and 20 members and is the most commonly encountered pod in the Northern resident killer whale community. This community is found in coastal waters ranging from mid-Vancouver Island up through the Queen Charlotte Islands, although A1 pod has yet to be seen this far north. The community is made up of three clans known as A, G and R clans, each possessing a distinctive dialect and consisting of several related pods. A1 pod belongs to the biggest clan, A clan.

Early research and naming

A1 pod was the first pod identified by Michael Bigg and Graeme Ellis in 1972. Bigg’s pioneering photo-identification system actually originates from the regular encounter of a female whale with a distinctively torn dorsal fin.[1] The whale, named Stubbs, was re-sighted in 1973, which gave Bigg the idea of photographing the dorsal fin of each killer whale he and Ellis encountered.[2] Thus, Stubbs was aptly given the alphanumeric code A1, which also became the name of her pod. Another female orca belonging to Stubbs’s pod also had a very recognizable dorsal fin with a big nick on the lower edge and was named A2, but became better known as Nicola. During the summer of 1973, A1 pod spent a considerable amount of time with A4 and A5 pod, which led researchers to believe they belonged to the same group. When it became clear to researchers that these whales spent a significant amount of time apart from A1 pod and had just happened to be travelling together when first identified, they were named A4 pod and A5 pod. Moreover, researchers discovered that A1 pod generally split during winter months into three subpods or matrilines: A1 subpod, A12 subpod and A2 subpod.

Evolution of the pod

For reasons unknown to researchers, the three A1 subpods have steadily been spending increasing time apart from each other since the 1980s. While in the 1970s, the three matrilines were together two thirds of the time, this figure dropped to one third of the time in the 1980s and to one fifth of the time in the 1990s. Today, the A1 matrilines are typically encountered separately and the coherence of A1 pod as a group is sometimes debated. Between the 1970s and 1990s, A1 pod didn’t grow much in size: it consisted of 13 members in 1973 and of 15 members in 1993. However, since the mid-1990s, A1 pod has been enjoying a steady growth, mostly due to the high number of reproductive females and the low number of sudden deaths that have hit its members. As of 2013, A1 pod consists of 20 members.

A1 matrilines

A36 matriline

Kaikash (A46) swimming in Johnstone Strait.

A1 matriline was renamed A36 matriline following the death of Stubbs (A1) in 1974, which meant that her suspected daughter Sophia (A36) would take on the role of matriarch. Sophia was also thought to be the sister of a large bull named Hardy (A20) (sometimes called Sturdy). As Sophia neared the end of her reproductive life in the early 1990s, it became clear to researchers that the A36 matriline would eventually die out, as Sophia’s only daughter, A44 died in 1975 at the age of 2. Sophia was the mother of three bulls, Cracroft (A32), Plumper (A37) and Kaikash (A46). One good example of the stability of killer whale society and especially of the bonds that unite brothers was when Sophia died in 1997. Instead of drifting apart, the three brothers stayed together and until the deaths of the two eldest brothers, were never seen travelling separately. As the A36s solely consist of bulls, they are a very recognizable group and are sometimes called “The Brothers” or “The Guys”. On November 8, 2004, the A36s were involved in a very unusual incident recorded by a camera of Orcalab. They were seen harassing a Dall’s porpoise, which resident killer whales never feed on.[3] Although the attack appeared violent, there is no evidence that the A36s actually ate the porpoise.

Current individuals:

Deceased individuals include:

Other deceased individuals include: Stubbs (A1; 1927–1974), Sophia (A36; 1947–1997), A44 (1973–1975), Hardy (A20; 1953–1992).

A12 matriline

The A12 matriline was named after its matriarch A12. Better known as Scimitar, she was given this name because her dorsal fin has a shape similar to that of a sword. The A12 matriline has grown substantially since it was first encountered and today spans 3 generations. Current individuals:

Deceased individuals include:

A30 matriline

Main article: A30 matriline

The pod today

A1 Pod is one of the healthiest resident pods, having had few early deaths and a high birth rate. The three matrilines are quite approachable and are usually not afraid of boats. Like in the 1970s, A1 pod is the most commonly encountered pod in the Northern Resident community, mostly due to its preference for the Johnstone Strait region during the summer and fall. Even at the peak of summer gatherings, the three matrilines are rarely seen all together. However, each group does spend more time with other A1 matrilines than with other pods. During the summer months, they spend a substantial amount of time with A4 and A5 pod who are their closest relatives. A1 pod is also one of the few pods whose winter grounds are at least partially known. They can be seen in the winter in the northern Johnstone Strait region and spend an important part of their time in the Broughton Archipelago. When Nimpkish (A33) died in the summer of 2009, Scimitar was seen alone for the first time. She was then spotted in the company of her daughter’s family as well as with the A30s. During the fall, she was seen with the A36s rather than with her daughter. Researchers such as Paul Spong believe she may have done so because of the presence of large bulls which she was used to travelling with.[8]

See also

References

  1. An online catalogue of the orcas of the northern resident community of the Pacific Northwest.
  2. Wild Killer Whale Adoption Program.
  3. , An online catalogue of the orcas of the northern resident community of the Pacific Northwest.
  4. , Orcalab.
  5. Drone shows life and death of killer whales
  6. , An online catalogue of the orcas of the northern resident community of the Pacific Northwest.
  7. Orcalab
  8. Orcalab

External links

Books

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