Hugh Bernard Noel Hynes, BSc, PhD, DSc, ARCS, FRSC, was a biologist and professor at the University of Waterloo and credited with founding the field of lotic limnology, the study of flowing fresh water. Hynes was born in 1917 in Devizes, England, and studied biology at Imperial College in London. After graduating in 1938, he enrolled at the University of London as an external student to study at the lab of the Freshwater Biological Association in the English Lake District. He graduated from the University of London in 1941 with a PhD in entomology; his thesis was on stoneflies (plecoptera).

During World War II, through a British government program to employ scientists in their professional capacity rather than as soldiers, Hynes was sent to Trinidad for six months to study tropical agriculture. In 1942, he married Mary Hinks and was sent to East Africa to work in the locust control program of the British Colonial Office. He spent the rest of the war attempting to eradicate locusts in Ethiopia, Kenya, and Somalia. After the war, he accepted a teaching post at the University of Liverpool. By the end of the 1950s, had established a solid reputation as an aquatic biologist; part of his work during this period related to river pollution.

In 1964, he came to the University of Waterloo to establish the biology department. He was its first permanent chair and spent the rest of his career there. He also spent two sabbatical years studying stoneflies in Australia. When he retired in 1983 he became a distinguished professor emeritus, but continued to work at his lab and with graduate students until 1993. In 1998, he was awarded the Naumann-Theinemann Medal from the Congress of International Limnological Society in Dublin, the highest honour available in the field of aquatic biology.

An internationally renowned biologist, Hynes published over 190 papers in the course of seven decades, and two of his books became classics in the field: The Biology of Polluted Waters (1960) and The Ecology of Running Waters (1970). He pioneered the field of modern stream ecology and was the first to show how food webs in streams depend on the surrounding landscape and how pollution changes them.