SEASONAL CHANGES
Lake trout may live upwards of 30 years, however, age determination is difficult beyond their eighth year and records to date are incomplete because tagging information is in its early stages. They reach sexual maturity in their sixth or seventh year and they may live to spawn again.
Spawning
Generally, spawning occurs in October, however, lake trout have been known to spawn as early as September and as late as November in the extreme limits of their range. Water depth for spawning may vary from as little as one foot to as much as 100 feet, but most spawning takes place in less than 40 feet of water.
The ideal bottom structure for redds is a rocky reef or a shoal with plenty of space between rocks to provide the fertilized eggs with protection during incubation. Males and females congregate over spawning beds after dark for the ritual. Fertilized eggs fall into the cracks and crevices between rocks and boulders. Incubation may take as much as four or five months, after which the young lake trout head for deeper water and the safety it provides. It is assumed that small lake trout exist almost entirely on plankton and lesser aquatic life for the first year of their life until they are able to forage for smaller fish.