John James Audubon left Charleston, South Carolina, in July of 1837 to make his way to New York City and then London to continue assisting in the completion of the first edition of Birds of America. While in New York working on booking an Atlantic crossing, Audubon maintained his search for birds to study and draw. Of those were “three pairs” of Purple finches not far from Waterford that he guessed were nesting in the vicinity. Also while in New York, Audubon met and began a close correspondence with Thomas Mayo Brewer (1814-1880). Brewer was born in Boston. In 1835, Brewer graduated from Harvard College and was elected a member of the Boston Society of Natural History. He then attended the Harvard Medical School and graduated in 1838. Brewer practiced medicine for only a short time before turning his attention to writing and publishing works mostly about birds. Brewer is best known for co-authoring A History of North American Birds (1874) along with Spencer Fullerton Baird (1823-1887) and Robert Ridgway (1850-1929).
After completing the publication of A History of North American Birds, Brewer focused much of his birdwatching on one bird that suddenly was doing a lot of flying around in Boston after its introduction in New York City in 1851: the House sparrow, or the bird that Audubon called “the sooty Sparrows residing in London.” Elliott Coues (1842-1899) and most of the rest of the science community raised alarm over the increasing numbers of the bird and campaigned for its extermination. Brewer argued against the killing of the birds that set off “The Sparrow War” which could be considered among the first of the many wars that are being fought today over the issue of invasive species.