The Water: Seasonal Variations: Where are All the Fish?
Seasonal Variations: A quick look at preferred water temperatures
Salmonids are attracted to their preferred water temperatures and spend most of their time within them. These temperatures, from 50-70 degrees Fahrenheit, are associated with the metalimnion. Typical hypolimnion temps range from 40-50 degrees, and the epilimnion 65-80 degrees. The boundaries between these layers are present at different depths and temperatures during the year, or may be thin or absent entirely in early spring or late fall.
Lake Trout prefer water from 48-52 degrees, placing them near the bottom of the metalimnion or top of the hypolimnion. Atlantic Salmon prefer 52-55 degrees and are found higher in the water column, along with Rainbow and Brown Trout. Look in, around, and above the thermocline, at temperatures from the low-to-mid-fifties to low sixties, with the Browns usually preferring the warmest water. Not that it's quite this simple, for all trout species can be found outside of their preferred temperature ranges at certain times. In winter, there is no fifty degree water anywhere, while during summer, the search for food may lead fish into either warmer or cooler water. The lake trout are for the most part bottom dwellers, the other trout pelagic and occasionally surface oriented.
The major baitfish species in Cayuga are alewife, smelt, sculpins, shiners, and panfish. The Slimy Sculpin is a benthic fish, living in the hypolimnion year round, and found at depths up to 300 feet in Cayuga, and possibly more. The sculpin is found in water from 35-55 degrees. Lakers are the primary predator of this fish, though many other benthic (bottom) feeders do prey on it as well.
The alewife prefers slightly warmer temperatures and adults are usually found between 52 and 55 degrees Fahrenheit. The young of the year and immature alewives are found at water temps above 60 degrees, usually above the thermocline. The adults are rarely found in or above the thermocline except during spawning periods (late spring - early summer). Alewives exhibit a fairly wide diurnal migration, generally moving up in the water column during the day, and down at night, though other factors can influence this greatly, such as available food supply and amount of incident light. That is, they will retreat from a bright sun, but are in general attracted to light. During spawning the alewives invade the gravel sections of shoreline at night and can be scooped off the surface with a dipnet- once I even used my bare hands!
The Rainbow Smelt, an introduced prey and sportfish, has a widely varying population in the lake. During high population years, schools of smelt run the creeks in spring, and trout species of all kinds can be found just offshore. Rainbow smelt prefer water around 48 degrees. Recently the numbers of smelt in the lake have been fairly low and the fishing activity has shifted. One of my first real fishing experiences was a fantastic smelt run at a local creek, but it's very hit or miss these days. Great spring fishing can be had near the creek mouths for trout, but that is also currently hit or miss.
The various species of shiners are found in shallow water in winter, providing forage for surface oriented winter fish such as rainbow trout and atlantic salmon. The smelt and alewife remain in deep water during the winter months. The questionable population of Cisco spawn in winter and may provide some forage as well, if there are any left.