HARDHEAD; BULLSEYE The hardhead (by which name it is commonly known to fishermen) resembles the common mackerel. A smaller fish, growing to a length of 8 to 14 inches only. Tremendously abundant and so plentiful off Provincetown from 1812 to 1820 that three men and a boy could catch 3,000 on a hook and line. But it practically disappeared from the United States coast some time between 1810 and 1850. It is interesting to note that destructive methods of fishing had nothing to do with the case, for its disappearance antedated the introduction of traps, pounds, or purse seines; it also antedated the reappearance of the bluefish; hence cannot be blamed on these sea pirates. So completely did the hardheads vanish that the Smithsonian Institution tried in vain for 10 years prior to 1879 to obtain a single specimen. In its years of plenty, which fall at long intervals, however, the chub mackerel is likely to appear wherever mackerel do off the Massachusetts coast, especially about Provincetown.
From Fishes of the Gulf of Maine by Bigelow and Schroeder, 1953
Online courtesy of MBL/WHOI
http://www.gma.org/fogm/Pneumatophorus_colias.htm
Good Morning Gloucester 