New Coccidia from the Spiny Dogfish Shark (Squalus acanthias) and Great Sculpin (Myoxocephalus polyacanthocephalus)

New coccidia from the spiny dogfish shark, Squalus acanthias, and the great sculpin, Myoxocephalus polyacanthocephalus, from waters around the San Juan Islands, Puget Sound, Washington, are described and named. Thirty-one species of bony and two species of cartilaginous fishes were examined. Twenty-eight of 71 dogfish and one of four sculpins were infected with coccidia.

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Harbor porpoise (Phocoena phocoena) recovery in the inland waters of Washington: estimates of density and abundance from aerial surveys, 2013–2015

Canadian Journal of Zoology ◽

10.1139/cjz-2015-0236 ◽

2016 ◽

Vol 94 (7) ◽

pp. 505-515 ◽

Cited By ~ 3

Author(s):

Thomas A. Jefferson ◽

Mari A. Smultea ◽

Sarah S. Courbis ◽

Gregory S. Campbell

Keyword(s):

Puget Sound ◽

Distance Sampling ◽

Line Transect ◽

Inland Waters ◽

San Juan ◽

Phocoena Phocoena ◽

Harbor Porpoise ◽

San Juan Islands ◽

Juan De Fuca ◽

Harbor Porpoises

The harbor porpoise (Phocoena phocoena (L., 1758)) used to be common in Puget Sound, Washington, but virtually disappeared from these waters by the 1970s. We conducted systematic aerial line-transect surveys (17 237 km total effort) for harbor porpoises, with the goal of estimating density and abundance in the inland waters of Washington State. Surveys in Puget Sound occurred throughout the year from 2013 to 2015, and in the Strait of Juan de Fuca and the San Juan Islands (and some adjacent Canadian waters) in April 2015. We used a high-wing, twin-engine Partenavia airplane and four observers (one on each side of the plane, one looking through a belly port, and one recording data). A total of 1063 harbor porpoise groups were sighted. Density and abundance were estimated using conventional distance sampling methods. Analyses were limited to 447 harbor porpoise groups observed during 5708 km of effort during good sighting conditions suitable for line-transect analysis. Harbor porpoises occurred in all regions of the study area, with highest densities around the San Juan Islands and in northern Puget Sound. Overall, estimated abundance for the Washington Inland Waters stock was 11 233 porpoises (CV = 37%, 95% CI = 9 616 – 13 120). This project clearly demonstrated that harbor porpoises have reoccupied waters of Puget Sound and are present there in all seasons. However, the specific reasons for their initial decline and subsequent recovery remain uncertain.

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Biology and Management of Dogfish Sharks

Biology and Management of Dogfish Sharks ◽

10.47886/9781934874073.ch9 ◽

2009 ◽

Keyword(s):

Life History ◽

Pacific Coast ◽

Puget Sound ◽

Squalus Acanthias ◽

Spiny Dogfish ◽

Dietary Analysis ◽

Strait Of Georgia ◽

Food Items ◽

Abundance Estimates ◽

Commercial Species

Abstract.—Spiny dogfish <em>Squalus acanthias </em>have been an important commercial species on Canada’s Pacific coast for more than 130 years. In this study we show that the spiny dogfish life history results in juveniles remaining in pelagic waters for 10–15 years after birth, with lengths up to about 60 cm. Abundance estimates show that the numbers of these young dogfish, as well as some older dogfish in the pelagic waters, appear to represent a relatively large percentage of the population in these two regions. Dietary analysis shows that while euphausiids and teleosts constitute the major food items, regardless of size/age, dogfish feed on a number of species within the ecosystem. After about 15 years, there is a movement into demersal habitats where individuals eventually mature. Because dogfish are long lived, and because they are found throughout the pelagic zone and demersal habitats, it is probable that they play a key role in the Strait of Georgia and Puget Sound ecosystems.

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