In late December, as the early formed ice began to allow Put-in-Bay fishing, it was quite apparent something was different in the water.
There were noticeable numbers of dying fish floundering near the ice’s surface and in many cases, coming up through the ice fishermen’s holes. They are so lethargic they can be easily caught with a minnow net or by hand. Not unexpectedly, these were confirmed to be Eastern gizzard shad, named for the prominent gizzard they use for grinding algae.
Thought by many to not be native to the Great Lakes, they were likely first allowed into the Lake with the construction of the Ohio-Erie Canals, which allowed their migration from the Ohio River to Lake Erie. The most numerous fish species in the lake by the end of the summer, they are highly sought by predatory fish as a rich food source, especially in the fall as they bulk up for winter survival and spring spawning. They are largely responsible for the fast growth rates and great size Lake Erie walleye are noted for.
Mainly, shad are a warmer water species which do not tolerate water below the lower 40-degree range. As the temperature drops further, over 90% die off from cold stress. Luckily, the surviving adults, which can grow to sixteen inches in Lake Erie, are extremely prolific, spawning several times throughout the spring and summer. In many larval fish samples, over 80% of the larval fish species collected in the nearshore areas, rivers and marshes of Western Lake Erie are gizzard shad. But while it is perfectly normal for shad to die off over the winter, they usually do it along the mainland shoreline, where they seek refuge in the warmer water coming into the lake from a variety of warm-water discharges-factories, sewage treatment plants, spring-fed streams and especially power plants.
Huge schools of shad in these areas attract several species of gulls and diving ducks, which provide superb bird-watching opportunities. But, when shad migrate up an intake of a power plant, their numbers can be so overwhelming that they can clog the water pumps and shut down the facility. With the rapid onset of winter, after a very mild autumn, they may have gotten caught by surprise as they enjoyed the abundant algae supply in the open waters of the lake, they couldn’t seek the warm water before the cold stress began to take its toll. Speculation among many of the Put-in-Bay Fishing members suggests the slow walleye fishing is a result of all of the shad in the area.
While it is likely the larger walleye are having an easy time filling up on these helpless 4-to-6-inch shad, the younger walleye are not large enough to be able to benefit by the easy pickings. As soon as the walleye schools get into the area, expect the Put-in-Bay fishing to improve, relative to the current walleye population size. As evidenced by the fantastic fall fishing that was enjoyed off of Huron this November and into December, there are still many survivors of the massive 2003 walleye year class available, which are now mostly trophy fish over 25 inches long. The 2007 hatch are now checking in around 17-19 inches. The numerous 2010 hatch, which are only about 8 inches long, representing the keepers of 2012 and beyond, need to be handled with care when caught. Yellow perch have had more consistent hatch success and survival over the past several years, are not able to eat the dying shad and have been providing some of the best early ice action. Expect better numbers of bigger fish this year, as the slightly too small fish of last fall grow throughout the coming months to ones which are much easier to clean, especially by this summer and especially the traditional fall perch season.