Blueback Trout Reproduction
As with all charr, the Blueback Trout spawns in the fall, in the months of September and October.
They seek out gravel or rock shoals in lakes and in slow pools in rivers.
Spawning depths may vary from three to 15 feet where they make their nest. The depth can vary from year to year depending on the amount of rain fall. In some years, they have even been known to spawn in as little as 1.5 feet of water.
The redd is prepared by the female who uses her tail fin in a sweeping motion along the bottom of the river or lake. in shallow water, ripples can be seen as the whole event is a rather aggressive procedure.
Female Egg Deposit
The female Blueback Trout may deposit as many as 5,000 eggs, with most laying between 3,000 to 5,000 eggs. As they are deposited, the male Blueback Trout fertilizes the eggs.
Unlike most salmon species, Blueback trout survive to spawn many more times. However, the females are able to spawn every second or third year.
Once the eggs are laid, they are covered in the bottom gravel and hatch the following spring, between April and July. While their habitat is limited, their range in spawning can be significant.
Climate Effects
However, the time of year is not the focal point that dictates when they will spawn, it is the water temperature. Due to the continental climate of the north eastern United States, spring may come as early as March or may be delayed until June.
In 2012, 2007 and 2004, winters were so mild that spawning stated in late March.
However, in the early 1980s, winters were so long and harsh that it was not until June before spawning took place.
Fatal Introduction of Smelt and Atlantic Salmon
Blueback Trout were very popular in Maine and parts of Canada bordering Maine until the early 1900s. The Blueback Trout were served in local restaurants, Inns and Hotels. However, this all changed when Atlantic Salmon and Smelt were introduced to the area lakes.
Smelt were a problem because they competed with Blueback Trout for food and because they grew quicker, smelt reduced the Blueback’s food base.
On the other end of the food web, Atlantic Salmon fed on young Blueback trout and would even go after adult Blueback Trout. As a result, anywhere that Atlantic Salmon have been introduced have seen the populations of Blueback Trout disappear.