One of the most striking and best known marine mammals, the Orca (often referred to as a Killer Whale) is the largest variety of dolphin and is considered the ocean’s top predator. They are easily identified by their glossy black coloring with distinctive white markings near the eyes, behind the dorsal fin and along the belly. These markings, along with the shape of the dorsal fins, are so distinctive that research scientists use them to identify individual whales. These massive animals can reach lengths of up to 32 feet (9.8 m) for males and 28 feet (8.5 m) for females. The largest males can weigh in around 11 tons (9.9 t).
Orcas generally lives in extended family groups called “pods” that are led by a single female known as the “matriarch.” The animals in the pods are highly social with each other, sharing responsibilities for hunting and protecting the more vulnerable members of the group including the calves. They will often communicate with each other, even over long distances, through a series of vocalizations which include clicks, chirps, squeaks and whistles. It is believed that Oregon’s coastal waters are habitat for the yearly migration of three major Orca family groups, known as J, K, and L pods. These regular visitors are known as “Southern Residents.” Orcas who travel in smaller groups and do not have as rigidly set migration patterns are referred to as “transient pods.” The Southern Resident Orcas eat primarily fish, including salmon.
The Southern Resident Orcas spend May through October around the San Juan Islands and southern Vancouver Island in British Columbia. The rest of the year they largely disappear… and researchers aren’t exactly sure where they go although it is suspected that they are in Oregon coastal waters due to numerous sightings. Part of the ongoing conservation efforts for the Southern Residents will include tracking the pods, a process that may utilize sophisticated underwater listening devices (hydrophones) that pick up and record Orca “song.” If scientists can better understand the migration patterns of these whales, we might be more successful at preserving and even bolstering their numbers.
The Southern Resident Orcas are imperiled, listed as “endangered” in both Canada and the United States.