Bull Trout Eggs - These eggs are “eyed,” meaning that the embryos inside are viable and developing. The dark spots in the middle egg are eyes, and the darker lines mark the beginning of the spine. Bull trout eggs hatch in the late winter and early spring.
Bull Trout Alevin - Newly hatched fish (called “alevin”) remain in the gravels of the redd site and get nutrients from the egg sack on their bellies. Once an egg sack is absorbed into the body (termed “buttoned up”), the tiny fish may begin to work its way out of the gravels and into the stream.
Bull Trout Fry - Bull trout fry typically range from 1 to 1 ½ inches (26-38mm) when they emerge from gravels in the Cedar and Rex rivers in late February. During the early spring, they use the slow-moving shallow water at the shoreline.
Bull Trout Juvenile - As bull trout grow, they use deeper portions of the river habitat, often seeking shelter between cobbles or boulders. The larger juvenile in this photo is about one year old. Between the two bull trout is a rainbow trout fry—an excellent food source for growing bull trout.
Bull Trout Staging - Bull trout often group at the mouth of a river before they begin to spawn. These bull trout were observed circling in a deep pool just upstream from Chester Morse Lake in the Cedar River. The next day, all these fish had moved out of the pool.
Spawning Pair - These bull trout are spawning in a floodplain channel. The female digs a “pit” in the gravel, cleans out fine sediment, and lays her eggs. After the male fertilizes the eggs, the female covers them with gravel for protection during incubation.
Bull Trout Redd - Bull trout redds are often easy to spot early in the fall because the female’s preparation of the site for her eggs removes algae from the gravel. Redds are most often found in the watershed in fairly shallow water, where pools tail-out into riffles.