Anglers fishing northern Lake Michigan are well known for targeting lake whitefish and lake trout - jigging off the bottom for them for eons.
But in the last decade a new fishery has emerged - and its one that's surprising a lot of people.
"The new thing in the area is cisco (formerly known as lake herring)," shared Heather Hettinger, a fisheries biologist based out of Traverse City. "Obviously these fish have been around forever but they used to not be very big in size. About 10 years ago anglers started catching much bigger fish - especially as the lake whitefish population numbers started to tick down."
During that time anglers started targeting cisco versus lake whitefish, with available locations to fish for them expanding as well.
"A hot spot in this area to fish for cisco is east Grand Traverse Bay," Hettinger said. "But really there are fishable populations in the west bay up to Elk Rapids, Charlevoix and Petoskey."
Hettinger explains that you can fish for cisco any which way you want - including trolling, jigging from a small boat, and pier fishing. She says most anglers are happy about this newer fishing opportunity - but there's still so much we don't know about this species.
Enter Jory Jonas, a fisheries research biologist based out of Charlevoix who is fascinated by this growing effort - and is aiming to figure out why it has changed over time.
Cisco and lake whitefish are technically related, yet for several years lake whitefish have been on the decline while cisco populations seem to be thriving. These fish spawn around the same time and grow up in similar environments - so why the big difference?
"It's so interesting to me, as a scientist, as to why these two species are headed on two different trajectories," explained Jonas. "I need to find out where their life cycle bottlenecks are. I have hypotheses, but nothing definitive. The first place I want to go to is larval fish - when you come out of an egg and you're a larvae, is there a problem with the size of Lake Michigan's zooplankton and can your mouth allow you to catch them?"
Like many things in Lake Michigan, zooplankton have changed (become larger) and species compositions are different then 10 to 15 years ago. Jonas thinks lake whitefish - with smaller mouths - are having a tougher time catching those zooplankton while cisco are having a much easier time and are capitalizing on the available food source.
"What's even more fascinating is that as these cisco grow, they're turning into a totally different type of fish," she said. "When we type out some of the larger fish we're seeing caught on Lake Michigan they're actually piscivorous - meaning they're eating other fish! It's hard for me to convince folks that cisco are actually top predators, like Chinook salmon or lake trout - they really aren't prey!"
It should be noted that in addition to the northern Lake Michigan cisco opportunities, larger populations are starting to show up in some connected inland lakes as well.
"This past winter Portage Lake in Manistee County had good, fishable ice - and anglers reported catching cisco there," Hettinger shared. "I've heard rumblings from other ports with drowned Rivermouth lakes that are started to have similar stories. Ports as far south as Ludington and even Muskegon are reporting cisco both through the ice and open water."
Anglers who previously caught cisco in northern Lake Michigan would consider a 12-inch fish as decent size, but reports have become much more regular of fish in the 22 to 26-inch size range. If you catch some, the key is knowing how to harvest them.
"I think they're delicious - but I recommend bleeding them out as soon as you catch them and getting them on ice quick," said Hettinger. "And get up here - this cisco fishing is really awesome for those who want to pursue it!"
Jonas shares similar sentiments and has noticed a gain in popularity even among those with insider knowledge.
"Folks from all over the state are coming here to fish for cisco - event other fisheries biologists and researchers," she said. "What's so cool is that this is a native species which was nearly non-existent and it is recovering for reasons we don't yet understand."
For information on fishing for cisco, including regulations, the DNR's Fishing page.