By Wyatt Fournier, NOAA Fisheries, on the Northwest Explorer

Spiny dogfish and pups

We have completed sampling the Yakutat Bay and Kayak Island transects with little success catching our focal fish species. This region has produced moderate to large catches of spiny dogfish (Squalus acanthias), which continues the trend that began in the northern portion of our southeast Gulf of Alaska grid. The spiny dogfish is the most abundant shark in our oceans and is caught for human consumption, used in liver oil, pet food, fishmeal, fertilizer and leather. It is the only shark that supports fisheries as large as those of the commercially important bony fish. A unique life history characteristic of the spiny dogfish is that they are ovoviviparous, meaning that the embryos develop and are retained within the mother’s body until they are hatched and released. Females can reach 100 cm in length and have a gestation period that can last as long as 24 months, which is longer than any other vertebrate (even whales and elephants). Although the females may produce up to 20 young per litter, the individual pictured below was found with only two pups.
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