A flowing-water respirometer was used to measure oxygen consumption of five species of estuarine fish: pinfish, Lagodon rhomboides; black sea bass, Centropristes striutus; Atlantic croaker, Micropogon undulatus; oyster toadfish, Opsanus tau; and mummichog, Fundulus heteroclitus. The relation between the amount of oxygen consumed and body size, in general, may be expressed by the formula Q = a Weightk, where a and k are constants derived from experimental data for a species. Some investigators have stated that k values do not vary significantly among species of fish. In my investigations the value of k did vary significantly between certain species. The values obtained for k are given and the methods used to measure respiration rates are discussed.
