A technical report from the Washington Department of Fish and Wildlife and the Cascadia Research Collective details the decline of the harbor porpoise in Puget Sound in the s and reports that species numbers have increased over the past twenty years likely due to outside immigration. Harbor porpoises were once common in Puget Sound, but had all but disappeared from local waters by the s. Regular and numerous anecdotal sightings in recent years show that populations of these cetaceans are now increasing and may be approaching their former status.
Harbor seals and harbor porpoises in the Salish Sea are showing a relatively high presence of antibiotic-resistant bacteria. A paper in the journal Oceans suggests that these findings may indicate a wider problem among other species in the region. A paper published in the journal Oceans in describes cases of prey-related asphyxiation in harbor porpoises along the U.
West Coast. The findings suggest that a majority of cases involve non-native American shad and that asphyxiation tends to occur more with reproductively active females than other age and sex classes. A paper published in Frontiers in Marine Science describes details of the fungal disease Mucormycosis which has caused the death of harbor porpoises, harbor seals and one orca in Puget Sound in recent years.
The authors discuss the implications for local marine mammals, specifically the endangered southern resident killer whale population. A few species of animals can look a lot like a dolphin, especially from a distance.
We have created this short video to help people identify which species they are seeing. Many of these species, expect for the harbor porpoise, are not commonly sighted in Puget Sound. If you see unusual marine mammal species, please contact Cascadia Research.
We are interested in tracking the presence, behavior, and condition of these animals. During the earlys, Daniela Maldini of Okeanis sighted Miss numerous times during her Masters work studying the northern range expansion of this stock as they moved into the Monterey Bay area, where Daniela's catalog from those early years show pictures of miss every year from In fact Miss was one of the pioneers in the area, earning her the ID 2 in the photo-ID catalog for Daniela's study area.
As the stock continued its northern expansion, Miss spent less time in Monterey Bay. After , she was only seen along the coast north of San Francisco, often pushing the limits of where members of this population are expected to be seen. Around 6 months after this last sighting, Miss was one of the dolphins that showed up in the Puget Sound.
As with the different ecotypes of killer whales that we are familiar with in Washington resident, transient and offshore , there are two ecotypes of bottlenose dolphins off the west coast of the United States coastal and offshore.
The coastal animals are generally smaller, a lighter grey, and stick to the warmer shallow waters near shore, while offshore animals are larger and usually darker grey, sometime appearing black.
The California coastal stock of bottlenose dolphins is a genetically distinct population of about animals that remain in a narrow corridor up to approximately 1 mile offshore between Ensenada, Mexico, and Sonoma County, California, just north of the San Francisco Bay. By using dorsal fin photos to track them, researchers have found that some individuals in this population can be highly mobile, engaging in long-distance movements north and south across their range in California.
When the dolphin left the other boat, Tritt did a circle of the area. Before long the dolphin appeared just off his bow. As Tritt sped north the dolphin kept pace, at times leaping on either side of the bow.
The animal is a long-beaked common dolphin Delphinus capensis , a species with a global range in warm-temperate and tropical waters that is the most abundant cetacean in the world, with a population estimated at 6 million.
These dolphins are numerous off the coast of Southern California and Mexico, living in groups of hundreds or even thousands of individuals, but rarely do they venture farther north. In , according to Cascadia Research Collective, two pods of these dolphins made an unprecedented excursion into Puget Sound, finding their way to its southern rea ches. Most soon exited, but a handful of individuals stayed behind and have been living in South Puget Sound ever since, spending much of their time in Case Inlet, near Olympia, and around Anderson Island, with occasional forays as far north as Tacoma.
One male in particular, nicknamed Cinco, has been photographed often over the last year. Usually alone, Cinco is described as being playful and having a breach like a skipping stone. Experts identify individual dolphins by examining photographs of their dorsal fins — something Key Peninsula boaters can aim to record to help the research collective better understand these rare animals.
The first, the more well-known bottlenose dolphin, reached Puget Sound a handful of times over the last few decades, most notably in the fall of when five or six individuals spent several months in Washington waters.
One of them was photographed well enough in Hale Passage to be identified by researchers in California.
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