Great Lakes Salmon And Trout

Remembering the Eye in the Sky Venerable salmon reporter John Oravec first spread the word through In-Fisherman about “eye-in-the-sky” tactics 16 years ago, soon after daily satellite maps of the Great Lakes first appeared on the Internet. “Before the captains of Lake Ontario begin to apply any seat-of-the-pants savvy for finding the stable offshore honey holes, we go to coastwatch.msu.edu for a surface-temp map with a GPS overlay,” Oravec says. “It saves time and gas. With the boat on a trailer, you can chase the best water more effectively than many a gas-guzzling charter boat can.” Satellite maps show surface temperatures and reveal where the coldest surface water was when the photo was taken (so, get up early and get on the Net before pulling out of the driveway). Coldwater masses can move or dissipate quickly. The spots representing the shortest distances between warmwater and coldwater masses are the places to circle on a satellite map. That’s where the best thermal bars and other “invisible structures” exist near the surface of the lake. The “stability-zone” angler uses satellite maps, too. But he might circle the spots where coldwater masses appear closest to shore, then go there and use down temps to determine whether salmon are inshore or in pockets along the way out. If 49°F to 52°F water can’t be found anywhere above bottom, it’s time to head well offshore, to the largest area of stable water in the lake, hunting along the way. Satellite maps tell us what’s happening on the surface, but the zone of stability primarily encompasses a buffered body of water beginning somewhere under the surface and extending through the middle of the water column, often all the way to the bottom. Temperature gauges on downriggers or self-contained, depth-probing thermometers become necessities in the search for the stability zone.

“In the case of a lesser upwelling, with lighter north winds or shorter duration, warm water remains in pockets like harbors, shoreline cuts, and bays. I run out just beyond the harbor after north-wind events and storms to drop a cannonball with a down-temp probe. If I run it down 20 feet and find 49°F to 52°F water, I know there are some kings in the harbor, even in the middle of summer—even on a 90°F day.

“If the wind stays out of the north for days, baitfish stay on the beaches and kings remain shallow. I’ve won several summer tournaments following this pattern. On our best day in shallow, right at the beginning of August, we ran #5 J-Plugs clean—no attractors—about 150 feet behind the boards at 4 mph. It was hot enough that it felt like fishing for tarpon in Florida. Kings were driving alewives into big, dark pools. We could see alewives streaking through the sides of the swells and flying into the air. The deepest water we fished that day was 10 feet and we had 12 fish for about 160 pounds by 11 a.m. As soon as the wind switches to the south, though, those shallow kings are gone.

“In shallow, I deploy zones of baits. In the close zone, or closer to the boat, I drop spoons back 45 feet on one side and 60 feet on the other with downriggers, and sometimes on the center rigger I have a lure back 100 feet. I drop the balls about 7 feet down when I want the lure to scuff bottom on the inside of a turn. Lures colliding with bottom, raising a cloud then dragging a plume along when pulled forward, produce massive strikes from kings at times. In the away zone, out to the sides, I run boards with J-Plugs dropped back 100 feet on the shoreward side and 150 feet back on the other.

“When the water starts to warm again in the shallows, the kings begin drifting out toward midlake. The harder a south wind blows, the faster kings retreat. When the temperature change is gradual, kings may hold in depths of 20 to 40 feet long enough to be approachable with leadcore on boards. I find that scenario with down-temperatures, too. Of course, all the familiar signs, like bug slicks, abrupt changes in surface temperature, and feeding birds provide all the reason you need to stop. But if I can find 49°F water with the down-temp probe, that’s my final assurance that kings will be there. I run spoons or J-Plugs clean (no attractors) on five colors of leadcore. With 40 feet of mono, that rigging takes the lures 190 feet back and 20 feet down, perfect for picking off kings hovering in no-man’s land when water temperatures are climbing slowly.”

Patterns that develop inshore after storms and upwellings are just shadows of a larger, more consistent pattern. The flip side of the upwelling story occurs out in the infinite blue, where conditions rarely if ever change so rapidly.