Stephen Alfred Forbes (May 29, 1844 – March 13, 1930)[2] was the first chief of the Illinois Natural History Survey,[3] a founder of aquatic ecosystem science and a dominant figure in the rise of American ecology.

[4] While already famous as an economic entomologist, Forbes undertook studies of massive fish mortality in Lake Mendota, Wisconsin.

[5] Notable for both conceptual creativity and the use of innovative quantitative methods, his work foreshadowed the ecosystem concept as well as modern ideas of behavioral ecology and food web dynamics.

[9] Born into a pioneer family, of Scots and Dutch ancestry,[10] he spent his youth near Freeport, Illinois, in Stephenson County.

Beyond his common school education up to age 14, Forbes's only formal studies at the secondary level were three months during the winter term of 1859–1860 at Beloit Academy in Wisconsin, a year at Rush Medical College in Chicago after the Civil War, and the spring term of 1871 at Illinois State Normal University in Normal, Illinois.

Shortly after his fourteenth birthday in 1858, young Stephen witnessed one of the eight famous Lincoln–Douglas debates staged throughout Illinois for a seat in the U.S. Senate.

His first published works appeared in American Entomologist and Botanist in 1870, and a new plant species, which he was the first researcher to describe, was named Saxifraga forbesii in his honor.

Forbes's extensive knowledge was not limited to entomology, but throughout his life he also studied and achieved distinction in ichthyology, ornithology, river and stream biology and pollution, and the taxonomy of Crustacea.