Maine Survey Shows Lake St. George “Bursting” with Brook Trout

The following was adapted from an article provided by the Maine Dept. of Inland Fisheries & Wildlife:

Lake Saint George in central Maine covers over 1,000 acres, has a maximum depth of 70 feet, and contains ample cold water and dissolved oxygen year-round—prime conditions for salmonids such as trout and landlocked salmon. The lake also contains lots of rainbow smelt and chaoborus (the larval form of phantom midges), providing a rich food source for predator fish. For a large waterbody, the conditions are ideal for the growth and survival of trout and salmon, which is highly unusual in central Maine.

Landlocked salmon and brook trout have been stocked annually in Lake Saint George since the late 1930’s. The salmon fishery is consistently top-notch. Stocked at an exceedingly high rate of 1 salmon/acre (1,000 fish annually), anglers routinely catch fish in the 3- to 5-pound range. Even larger fish are present, but not as common.

MDIFW fisheries biologists conduct a trap-net survey on Lake Saint George each fall to gain a sense of its fish populations. The results are similar year after year—with the exception of this year’s survey. While salmon growth and survival saw a slight uptick compared to previous years, the number of brook trout in the lake spiked considerably.

The lake’s brook trout fishery has always been robust, with 2-pound fish readily available. However, this year’s netting survey showed that brook trout numbers were remarkably higher than previous years, as shown by the following table.

 

  2009 2012 2015 2018
Number of Brook Trout 6 0 4 62
Average Length (in) 14.2 14.4 14.1
Average Weight (lb) 1.1 1.3 1.2

 

Biologists aren’t certain why the brook trout population has increased so dramatically, but it could be due to some recent changes in stocking size and numbers, combined with an increase in chaoborus productivity or smelt spawning success. The bottom line is that Saint George should produce some outstanding fishing over the winter and through next year.

The downside to the abundance of large salmonids is that they may impact the lake’s forage base, resulting in a less healthy salmon population in the future. In order to maintain a healthy equilibrium between predator (i.e. trout and salmon) and prey (i.e. smelt and chaoborus), Lake Saint George requires some immediate prey harvest, which is why anglers are being encouraged to fish it soon!