When you get a big one hooked up you can tell by the way it feels. Before you see it. And most times we don’t really know its size till it comes up. Then there’s the practical aspect of knowing what you have on the line.
From a distance, a twenty-two inch walleye looks a lot like a fifteen inch walleye. But biologially, in age, and in value, they is very different. Knowing the correlation between length and weight will help you form better expectations for your day out on the water. It will also help you manage your catch better as it converts guess work to strategy. These relationships are outlined nicely in the graph above.
Why Walleye Size Matters
It illustrates how mass increases with increasing size of fish and how this isn’t a straight line. Many angler don’t realize this. That 10 inch fingerling will weigh only a couple ounces and hardly register on most scales. However, when you pass that magic 20 inch mark the weight realy starts to increase.
Why does this matter? It is the reason we can distinguish between quantity fishing and quality fishing. Fishing doesn’t feel like “catching” anymore…you’re managing significant amounts of weight in your cooler/livewell.
Many of these size differences relate to age and sex. The size difference comes largely from the fact that females grows much faster and bigger than males. In fact by the time you get to a 26-inch walleye it’s virtually guaranteed to be a female. The big females contribute exponentially more eggs than their smaller counterparts. Protecting them matter for both recreation and biology.
A lot of fisheries have protective regulations or slot limits on fish in a particular size range. Often times you’ll find regulations stating that fish must be released if within a given length range. That means the largest spawners are protected while younger fish can be harvested. Following the rules protects the resource and keeps the fishing great year after year.
Estimating weight. Whether you’re on a chilly lake when it’s too slippery to get out of boat or you’re fishing a busy lake where weighing your catch won’t be possible, knowing how to estimate fish size without scales comes in handy. It works surprisingly well, actually, thanks to basic girth measurement. In general, all you need to do is measure the length then multiply that number times the girth squared, divided by some sort of common denominator. You don’t need complicated math; simply practice and use a tape measure.
For reference, the chart contains average weights, though there’s still natural variation. Seasonal cycles matter: A summer feed-up fish will weigh heavier than a lean winter one of equal length due to being full-bellied from heavy eating. Fall bites are especially rewarding as fish bulk up ahead of winter to make it through the cold months.
The other part of the puzzle is knowing what you’ve got. Once you figure out that sauger, walleye, and their hybrid offspring (saugeye) all look alike, you can use certain clues to tell them apart. A sauger will never have a white tip at the end of its lower tail lobe. Walleyes will. Spots on dorsal fins differ too from species to species. Know the difference, make sure your identification matches what’s happening on the boat. It’s more than just another checkmark. It makes this thing we love even more fun, and it means you’re complying with regulations.
What size fish do you target? That alone can dictate how you fish. Small walleyes may be caught in shallow weed edges on flashy lures. Larger ones may hang around temperature layers or hug deep structure in daylight hours. Crankbaits, jigs and live bait rigs all has their places at different levels. More critical than the latest gear is matching your offering to what the fish are doing. A plain hook with a night crawler can sometimes out produce some high tech lure. Walleye fishing is all about observing and patience.
While this size chart can be used as a guide, experience on the water is where you really learn how to read the signs, respect the rules and appreciate the growth of these predators. And once you catch that twenty five inch female, you’ll know exactly why they are protected so carefully. It is not just about the weight on the scale. It’s about maintaining the cycle for the next generation of anglers who will pursue that same quiet thrill.