Smelt drift from Brassua Lake, Moosehead Lake Region fishing report

By Tim Obrey, Moosehead Lake Region fisheries supervisor

Smelt make the world go around … at least on Moosehead Lake. They are the primary  forage fish for our prized coldwater gamefish. We’ve seen ups and downs in the smelt  population over the last 50 years and I can tell you unequivocally our lake trout and salmon would rather starve than eat something else. When smelt are in low abundance, our lake trout and salmon growth suffer, even though there are other baitfish for them to feed on. Our years of stomach analysis data confirm this. The situation can linger for years, as we’ve seen. That is why it is so important to keep the smelt population as robust as possible.

We monitor the smelt population using several techniques. For years, we have collected stomachs from our lake trout, salmon, and brook trout while conducting winter creel  surveys on the lake. It’s messy work but the data are invaluable. We can count and measure the forage items in the stomachs which are 80-100 percent smelt. We can also age the smelt in the stomachs to monitor age class strength.  

More recently, we’ve been monitoring smelt fry hatching in one of the lake’s tributaries. This is very intensive work, requiring staff to place a small net in the stream in the dead of night to catch a sample of newly hatched fry drifting downstream to the lake. It lasts about three weeks, but it gives us very good insight into the spawning success for smelt that spring. More about this in another report.

Moosehead Lake is fortunate to have what is essentially a 9,000-acre smelt hatchery just  upstream of the Brassua Dam. Smelt of all ages  drift downstream from Brassua Lake into the Moose River throughout the year. Some of these  smelt are still alive when they come down through the turbines, so anything that is not immediately gobbled up by awaiting salmon in the river, can contribute to the forage base at a later time. It is also likely that surviving smelt run back up the river in the spring during their spawning season, providing a boost to the Moosehead Lake smelt population. We monitor the smelt drift by placing a typical catch includes smelt and a few yellow perch  or bass coming downstream from Brassua Lake. We only sample a small section of the river and for 24 hours per week, so our catch is expanded to estimate the total catch for each week.

We completed this work in 2021, and again in 2024. In 2021, we estimated just shy of 200,000 individual smelt made their way downstream to the Moose River. We saw peaks in drift in late April associated with post-spawning movements of adults in Brassua Lake. We also saw a peak in December. We saw similar patterns but on a much larger scale in 2024, The total estimate for smelt drift in 2024 was close to1.3 million smelt. That’s great news for the lake trout and salmon in Moosehead Lake!