The Bulletin of the United States Fish Commission

Appearance of Dogfish (Squalus acanthias) on the New England Coast in Winter
By J. W. Collins (Letter to Prof. S. F. Baird.)

In the Cape Ann Advertiser of February 10, 1882, I find the following paragraph: "immense schools of dogfish, extending as far as the eye can reach, have appeared off Portsmouth, an unusual sight in winter." Is it not possible that the presence of dogfish in such abundance in that vicinity this winter may have something to do with the scarcity of the cod in Ipswich Bay?

It is a fact well known to fishermen that dogfish in summer will drive the various species of bottom fish from the grounds, and it may be that they are quite as voracious and troublesome to the cod in winter as in warmer weather.

Washington, D. C., February 18, 1882.