It can vary using days, but the center of April in Maine constantly ushers within the annual smelt runs from coldwater lakes up nearby brooks and streams. As every salmon angler is aware, these small rainbow smelts are the important meal supply for landlocked salmon.
Back in the Nineteen Seventies, my own family and I experienced remarkable, exciting salmon angling at a far-flung northern Maine lake. It was an angler’s banquet for 3 or four years. Then it closes down all collectively. It was like nature threw a switch and the salmon just disappeared.
What brought on the salmon famine? “Smelt crash” became on the lips of many disappointed fishermen, who sought to understand the cycle, which changed into now not specific inside the annals of salmon angling.
What reasons a smelt crash? What are the medical and organic nuances that affect smelt numbers and, for this reason, salmon survival quotes?
Greenville fisheries biologist Tim O’Brien and his staff ran diligently to find solutions to these questions in ongoing studies at Moosehead Lake, Maine’s maximum expansive sport fishery.
Put definitely; they inventory smelt fry populations with the aid of netting them at Lily Bay Brook. From there, via “headcounts,” they can extrapolate the gross wide variety of smelt fry that heads lower back into the massive lake. Some years the runs have been 7 million, and a few years, as excessive as nine million. Late within the summertime, they behave more populace surveys of the smelt survival fees at the lake.
O’Brien and his crew also study plankton occurrence. Plankton is the main meals supply for the smelts.
O’Brien, in his words:
“Recently, we commenced work on a brand new task that we hope will shed some mild at the biology of smell…Hit The concept was to broaden a observation to offer an index of abundance for young smelt and help recognize the herbal variant that often occurs in smelt populations. This work isn’t always applicable to Moosehead Lake. However, it can be useful for other large lakes in Maine. There were some studies that indicate young, newly hatched smelt can be challenging to excessive mortality if the suitable meals supply (plankton) isn’t gifted in the course of their initial two-week window after hatching and dropping out of the circulation.”
This organic dynamic and interdependence among the salmon, the smelt, and the plankton explain why sport fish control is the complex and fickle field.
As O’Brien explains within the following paragraph, angler agitation for extended salmon stocking on a lake is the incorrect manner to go if smelt numbers are on the margins. You would possibly call it “protective the seed corn.”
“Finally, we are hoping to combine the information from the summertime smelt tows with the plankton abundance and the spring hatch numbers to come across any adjustments in abundance that could be associated with loss of food. If we determine that the smelt is in low abundance, we could reduce our salmon stocking to guard the increase of our game fish. Or if everything is peachy, we should boom our stocking to enhance the trap at the same time as maintaining the good increase charges.”
Maine is, certainly, lucky — not best to have a crown jewel like Moosehead Lake as a gamefish repositor, however, to have seasoned, committed, and informed fisheries stewards like Tim O’Brien.