The New Jersey shore is a haven for many clam-catchers, and it became a nickname for people from the state. “Clam-catchers of Cape May” was cited in an 1835 book. “New Jersey, Clam-catchers” was cited in an 1845 list of state nicknames.
Clams are not a part of a New Jersey resident’s diet as they once had been, and the term “clam-catcher” is mostly of historical interest today.
Maryland had a similar 19th century nickname in “Clam Thumper.”
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The Life of Benjamin Franklin
By Mason Locke Weems
Philadelphia, PA: Published by Uriah Hunt
1835
Pg. 118:
Not many days after this, the man of God took his journey through the south counties of New-Jersey, calling the poor clam-catchers of Cape May to repentance.
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April 1845, Cincinnati Miscellany (Cincinnati, OH), pg. 240, col. 1:
New Jersey, Clam-catchers.
Chronicling America
23 August 1845, Ripley (MS) Advertiser, pg. 1, cols. 4-5:
NATIONAL NICKNAMES.—It will be seen by the following from an exchange paper that the people of every state have nicknames, and some very curious and ludicrous ones:
The inhabitants of Maine, are called Foxes; New Hampshire, Granite Boys; Massachusetts, Bay Staters; Vermont, Green Mountain Boys; Rhode Island, Gun Flints; Connecticut, Wooden Nutmegs; New York, Knickerbockers; New Jersey, Clamcatchers; Pennsylvania, Leatherheads; Delaware, Muskrats; Maryland, Craw-Thumpers; Virginia, Beagles; North Carolina, Weasels; Georgia, Buzzards; Louisiana, Creowls; Alabama, Lizzards; Kentucky, Corn crackers; Tennessee, Cottonmanics; Ohio, Buckeyes; Indiana, Hoosiers; Illinois, Suckers; Missouri, Pewks; Mississippi, Tadpoles; Arkansas, Gophers; Michigan, Wolverines; Florida, Fly-up-the-Creeks; Wisconsin, Badgers; Iowa, Hawkeyes; N. W. Territory, Prairie Dogs; Oregon, Hard Cases.
Chronicling America
4 July 1860, The Spirit of Democracy (Woodsfield, OH), “National Nicknames,” pg. 1, col. 7:
The inhabitants of Maine are called Foxes; New Hampshire, Granite Boys; Massachusetts, Bay Staters; Vermont, Green Mountain Boys; Rhode Island, Gun Flints; Connecticut, Wooden Nutmegs; New York, Knickerbockers; New Jersey, Clam Catchers; Pennsylvania, Leather Heads; Delaware, Muskrats; Maryland, Claw Thumpers; Virginia, Beagles; North Carolina, Tar Boilers; South Carolina, Weasels; Georgia, Buzzards; Louisiana, Creowls; Alabama, Lizards; Kentucky, Corn Crackers; Ohio, Buckeyes; Michigan, Wolverines; Indiana, Hoosiers; illinois, Suckers; Missouri, Pukes: Mississippi, Tad-Poles; Florida, Fly up the Creeks; Wisconsin, Badgers; Iowa, Hawkeyes; Oregon, Hard Cases.
25 July 1864, Indianapolis (IN) Daily Journal, “National Nick-Names,” pg. 4, col. 2:
New Jersey…Clam Catchers
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June 1865, The Wisconsin Journal of Education, pg. 328:
The following are the “nicknames” of the native inhabitants of the different States:
... New Jersey, Clam Catchers: ...
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U. S.
An Index to the United States of America
Compiled by Malcolm Townsend
Boston, MA: D. Lothrop Company
1890
Pg. 77:
NICKNAMES APPLIED TO THE PEOPLE OF THE STATES.
(...)
New Jersey…Clam-Catchers...From principal occupation of many of its poorer classes on the Raritan Bay Shoals.
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Universal Dictionary of the English Language
Edited by Robert Hunter and Charles Morris
New York, NY: Peter Fenelon Collier, Publisher
1898
Pg. 5344:
New Jersey. Clam-catchers.
21 December 1997, Boston (MA)
, “Hold that ketchup!” by Richard P. Carpenter, pg. M4:
Travel Trivia: If someone calls you a clam catcher, what state are you from? (Answer at end of column.)
(...)
Did you guess it? A clam catcher is the traditional nickname for a New Jersey resident. A clam grabber, however, is from the state of Washington. The information is from “Labels for Locals” by Paul Dickson (Merriam-Webster, $14.95).