ALGOMA TOWNSHIP, Mich. — The forecast called for sun with a chance of rain(bow trout).
Cascading from a metal pipe mounted to a climate-controlled truck that rest on a bridge perched atop the Rogue River, thousands and thousands of fish tumbled into the water below.
"Look at today, look at this fun," said Brandon Glass, a fisheries technician with the Michigan DNR. "Something different. It's fun to work with fish."
In late April, the Michigan DNR deposited 22,600 Eagle Lake rainbow trout into the Rogue River as part of its statewide stocking effort, which aims to boost low fish populations, restore biodiversity, and provide fishing opportunities for anglers.
"I've seen parts of the state I wouldn't have normally seen," said Glass, describing how his stocking truck has taken him from Pontiac to the far reaches of the Upper Peninsula.
READ MORE: Michigan DNR collects walleye eggs from Muskegon River
That day, Glass and another fisheries technician, Jared Thompson, cast off their slippery cargo at three different sites on the Rogue River, paired together as part of a study.
"I'm an angler myself," said Thompson, a former academic who left his desk for the outdoors. "It means a lot me to see other anglers get excited."
While both technicians transported Eagle Lake rainbow trout from the Oden State Fish Hatchery, one truck carried a larger variety, born earlier due to the hatchery manipulating their parents' exposure to sunlight.
"The only cue they have to spawn is the amount of daylight," said Glass, explaining how periods of light and darkness can have a physiological effect on plants and animals, a reaction referred to as photoperiodism.
By controlling their photoperiod, the hatchery made the trout breed 16 weeks earlier than normal, allotting their babies more time to mature before being released into the wild.
"We're looking to see which one does better," Glass said. "The bigger ones in this situation or the smaller ones?"
Despite dropping a total of 22,600 trout into the Rogue River, the mortality rate is high, Glass says, estimating that only 10 percent will live long enough to be pulled to the surface by fishermen.
If the bigger fish (10,400 in total) survive at a higher rate than the standard rainbow trout (12,200 in total), the Michigan DNR may continue to manipulate its photoperiod as a way to more efficiently stock the state's freshwater lakes and rivers.
READ MORE: Where, why and how the DNR stocks and rears fish
In total, DNR crews annually stock more than 20 million fish, including steelhead, lake sturgeon and salmon, travelling "well over" 100,000 miles in Michigan from March to early June.
