Niles' Weekly Register, edited by Hezekiah Niles, Vol. 20, from March to September 1821, p. 304*

Trout, a very large one

Mammoth trout.  At “Fireplace,” Long Island, about 70 miles from New-York, Mr. Samuel Carman, jun. on the 25th ult. caught at the “tail of his saw mill” a trout three feet in length and 17 inches round the girth, and weighing 13 lbs. 8 oz.  It was kept alive in a pen several days for the gratification of the curious, the largest trout ever caught before, in the remembrance of the oldest inhabitants, never having exceeded 5 lbs. in weight—seldom being more than 2½ lbs.

*Niles' Weekly Register containing Political, Historical, Geographical, Scientifical, Statistical, Economical, and Biographical Documents, Essays, and Facts; Together with Notices of the Arts and Manufactures, and a Record of the Events of the Times; H. Niles, Editor.