The Landlocked Salmon Spawning Run at Cross Lake Thoroughfare, Maine

naeus, is one of the most important coldwater game fishes in Maine lakes, yet detailed information is lacking on many phases of its life history. The reports of Charles G. Atkins, pioneer fish-culturist of the U. S. Fish Commission, preserved much of the early history of the salmon spawning run at Grand Lake Stream, the outlet of West Grand Lake, in Washington County, Maine. Cooper (1940) compiled preliminary information on the composition of salmon spawning runs in several of the larger Maine lakes. The present study contributes information on the composition and characteristics of the salmon spawning run in the Fish River Lakes, Maine, and makes comparisons with other Maine salmon populations. The Fish River Lakes comprise a chain of eight large lakes in the Fish River watershed of the St. John River drainage in Maine. Biological surveys revealed that most of the lakes are ideal salmon habitat, supporting important fisheries for salmon and brook trout. Descriptions of the lakes and their fisheries have been given by Warner (1959). The main spawning areas for salmon in the Fish River drainage are located in the river-like thoroughfares connecting the lakes. Fall spawning runs in two of these thoroughfares were sampled in the present study. Warner (1959) has shown that the salmon spawning runs in Long Lake Thoroughfare and Cross Lake Thoroughfare are composed of spawners from Long Lake and Square Lake populations (Fig. 1). Long Lake Thoroughfare originates as the outlet of Long Lake and flows about threetenths of a mile into Mud Lake. The 3.1 per cent of ripe body weight. The sex ratio of salmon spawners approximated 50:50. Most females spawned first at age IV or V; most males spawned first at ages III to V. Maiden salmon comprised over 70 per cent of the spawning run in three years. Tag return data indicated that some salmon