July 12, 2011
When we're planning a filming trip for In€‘Fisherman TV, it's a good idea to add at least one weather day. This is especially true during early season. Even if we're after pike in late summer into fall, it's often necessary. Cold Canadian and warm southern air masses push and shove in the skies over the North Country, bringing conditions from thunder and rain to warm and sunny, cold and windy, and everything in between. Weather can turn things sour in a hurry, but it also can mean filling the HD tapes with footage of giant pike just as quickly.
All of the species we target are affected by weather. Depending on the combination of conditions, it can cause fish to feed more aggressively or make fishing difficult. Some scientific tracking studies show responses in fish activity and habitat selection to changing weather, but many times results are inconclusive, because it's hard to isolate cause and effect between complex environmental and behavioral variables. Forecasting pike isn't an exact science, but the weather can help you determine what patterns to start with.
Bob Sampson is a barometer man. The outdoor writer, science teacher, and multispecies angler from Salem, Connecticut, has long been interested in the relationship between weather and his fishing success, whether he's after striped bass and summer flounder in saltwater, or pike and muskies in lakes in the Northeast. "I've been studying how barometric pressure affects fishing for four decades," he says, "but after purchasing a handheld Bushnell DNS Digital Compass with a barometer feature about 4 years ago, I started seeing results in real time."
Sampson believes that water temperature is a primary variable driving fish response, but he's convinced that pressure changes and associated weather play major roles in how good the fishing is. "I've seen that even small pressure changes, as little as 0.05 inches, were enough to turn the fish on or off [standard atmospheric pressure at sea level is around 30 inches of mercury]. And it depends on which way the pressure is moving.
"The students in my science class conduct experiments where they fish a local pond and keep track of the barometer. Bluegills are abundant and provide good sample sizes. Rising pressure brings the poorest success and dropping pressure has the highest catch rates overall. About 60 to 85 percent of bites are associated with some level of pressure drop."
Sampson is so convinced that, unless he has a commitment to go fishing, he's seldom out under bluebird skies and rising pressure conditions. "Steep pressure drops are best and often coincide with feeding sprees," he says. "It helps if it's due to an incoming storm front, which also brings darker skies and winds."
barometer or weather?
At this point I've probably stirred the pot on the debate about whether fish can feel barometric pressure changes underwater. The popular consensus is that fish can't feel changes in air pressure underwater, so it must be shifting weather conditions associated with air pressure changes, like fronts, that cue behavior.
Maybe we haven't been giving fish enough credit for their pressure-sensing abilities. After all, if fish can detect chemicals at the parts per billion level, and if certain animals can feel earthquakes before we do, and if dogs can be trained to sniff out diseases and detect a pending epileptic seizure in humans, why would we dismiss the ability of fish to detect even minute changes in air pressure which has a corresponding change in hydrostatic pressure?
Researchers with the Mote Marine Laboratory in Sarasota, Florida, found that movement of blacktip sharks was triggered by a drop in barometric pressure associated with Hurricane Gabrielle in 2001. They report that the juvenile sharks responded to the approach of the storm by moving to deeper water, before the arrival of bad weather, returning to shallow water after the storm's passage.
But does that mean sharks can feel pressure changes? The best way to find out would be to eliminate the weather factor altogether, and isolate the pressure factor, under controlled laboratory conditions.
Those findings with sharks prompted research by marine biology Ph.D. student Lauren Smith at the University of Aberdeen in Scotland to do just that. She's studying pressure-sensing abilities of sharks in the wild, as well as in the lab with the use of an altitude chamber, which can mimic changes caused by weather fronts. Prior research by her supervisor, Dr. Peter Fraser, shows that sharks sense pressure using hair cells in their vestibular (balance) system.
"In general terms, fish with swim bladders, like pike, are able to detect pressure changes at a threshold of 0.05 millibars," Smith says, "while fish without swim bladders, such as sharks, have a higher but still sensitive threshold of 0.5 millibars. Physiologically speaking, there's no reason why fish cannot detect barometric pressure changes." (The millibar is a metric unit of atmospheric pressure; standard atmospheric pressure is about 1,013 mb at sea level).
Smith explains how pressure changes in the atmosphere relate to water pressure and fish: "Say for example the air pressure rises from 1,009 to 1,010 millibars. The water pressure — the hydrostatic pressure — changes accordingly and acts as a transducer, relaying this information to the fish by having a direct effect on the swim bladder.
Can dropping pressure stimulate pike to feed more actively? "Lower pressure has the opposite effect of rising air pressure, in that swim bladder volume increases and causes the fish to rise in the water column," Smith explains. "One hypothesis is that falling pressure causes smaller fish to become active [and more exposed], attracting predators such as the pike. Perhaps pike respond to an interaction of barometric pressure change, both directly on its own swim bladder and indirectly through prey response."
For now, we don't know whether fish like pike can feel changes in atmospheric pressure underwater, but science seems to be supporting that they have that ability. Of course that's not to say that barometric pressure trumps any associated weather effects. But it's not to say that it doesn't either. It's a chicken- and-egg sort of conundrum.
Back to Pike Weather
"Even small dips in pressure under sunny or partly sunny skies, with no apparent change in the weather, can get the fish revved up for a short time at midday," Samson says. "If the forecast calls for bright skies and hot weather, I try to get out during the low light early in the morning before the bite slows or stops as the day wears on. Then around midday, I sometimes see that the pressure indicated on my handheld unit drops just a tick and there's a short flurry of feeding activity. I suspect the tiny pressure dips are caused by the heating of the air at the surface, causing the air to rise. It might be just two or three or four fish, but something happened to turn them on, and the small pressure change is the only thing I can detect."
Sampson finds that skyrocketing barometric pressure that moves in after major storm systems often makes for the worst possible fishing conditions. He says a classic example of this took place during the tail end of a Nor'easter, a coastal storm that hits New England. Nor'easters develop when lows containing warm air are drawn up from the south and clash with a colder, high-pressure air mass from the north. They typically blow through the region during fall and also bring major snowstorms in winter.
"As it approaches and even during the Nor'easter itself, pressure drops, winds are high, and skies are dark, creating excellent fishing conditions, providing the winds are tolerable and not dangerous," he says. "Then, as the storm moves through, cold, high-pressure Canadian air pulls in, killing the fishing for a few days in the process.
"This happened a couple years ago, when a major Nor'easter was buffeting our area," he recalls. "I had to work or the boat would have been launched early that morning.€‚I had caught pike of 12.5 and 18 pounds after work during two previous Nor'easters that fall, so I couldn't wait to get out during this third major storm in as many weeks.
"My boat was in the water by 3:30 p.m. and within 30 minutes I had landed one small pike, a 17.5, and a 15.5-pounder, which for Connecticut is a pretty good half hour of targeted pike fishing. Then winds began to swing around from the northeast to the northwest and there was brightness behind the clouds that hadn't been there when we arrived.
"A glance at the hand-held barometer indicated that the pressure had leveled off and was just beginning to rise as this storm cleared the area," he says. "With a sharp edge of clear blue skies pushing the storm up the coast, it was like Mother Nature hit a kill switch. We didn't have another strike for the remainder of the day, not even at sunset."
The Light Factor
"When anglers say that changes in barometric pressure are related to fishing success, they're probably right," says Gord Pyzer, In-Fisherman Field Editor from Kenora, Ontario, and former manager for the Ontario Ministry of Natural Resources. "Pressure shifts are often associated with fronts that can cause changes in temperature, cloud cover, and wind levels," he explains. "Over the years, I've seen on Shield lakes that weather and water conditions, in many respects, can be more important than food in determining pike activity and location.
"One of the factors that pike seem to be strongly keyed to is light. Dr. John Casselman, a former Senior Research Scientist with the Ontario Ministry of Natural Resources and a world-renowned pike specialist, has been conducting groundbreaking experiments in the laboratory, looking at ways light levels affect pike. By adjusting light intensity, he says, he can make pike become active at will, and make them inactive again. When he adjusts the light to the right level, pike rise up and execute search-and-feed behavior. He does it with a simple dimmer switch, and the results are totally independent of the pike being hungry.
"Casselman finds that pike go into their search-and-feed behavior when the light is adjusted to about 10 lux," Pyzer reports. "This intensity mimics the first light in the morning and the last in the evening. He says that from angling studies conducted during the open-water period, it's known that pike feed more actively on cloudy, overcast days than on bright, sunny ones. On days when light intensity is high, they feed more actively during evening and, to a lesser extent, in morning twilight.
"That may very well be the reason wind is beneficial," Pyzer says. "Waves act to break up the water surface pane, limiting the amount of sunlight that's transmitted through it. In summer, I target big pike in deeper water, an ideal spot being 15 to 25 feet deep around rock humps. But put a wind onto the shoals and the pike move up on them en masse. The wind drives them, creating the ideal light and temperature conditions. I suspect the same light effects occur when rain fronts and storms are approaching. Cloud cover increases, which reduces light intensity to levels that Casselman shows can activate pike into a feeding mode."
"Weather definitely affects pike," says In-Fisherman Field Editor Matt Straw. "In summer, the fishing can be good when a long-term rainy front parks itself for a while and brings consistent winds. Even shorter-lived rains and storms can turn fish on."
Straw recalls a trip to Nueltin Lake: "This lake's way up north on the Manitoba-Nunavut border, so the fish stay on a shallower weed pattern all summer. We were catching fish, and then a storm started billowing in over the trees. The skies darkened and we began to catch pike after pike, until the bottom dropped out and we had to stop fishing. When we went back out we had sunny skies and cold-front conditions, and the pike were so inactive we had to use our fishing rods to roust them out of the weeds to get them moving.
"I focus on three main patterns for pike during summer," Straw says, "and depending on what a lake offers, you might have one or more of these patterns to work with. If water temperatures are cool enough, you can find big pike on weedlines. If the water's too warm shallower, they can be out suspended in deeper open water, or positioned closer to bottom on deeper structure.
"If it's flat, calm, and sunny, suspended fish and weed fish get tough. The odds-on call is to target structure from 20 to 40 feet deep, but they can be as deep as 60 feet. That's when I bring out the snap-jigging routine. Find big areas of bait on sonar and pike should be there. I like to use a 1- to 1.5-ounce jig, like an Esox Cobra Head, but any standard bullet or football head works," he says. "Match it with a 7- to 8-inch plastic like a Bait Rigs Reaper or Mann's Jelly-Hoo. The Berkley Gulp! Eel is another one to try. Get to bottom fast and hit it hard, snapping the jig off the bottom by 6 feet or more. A 7- to 7.5-foot heavy flippin' stick with 20- to 30-pound braid is a good setup for this."
When cold fronts bring a tough bite, former In-Fisherman Professional Walleye Trail Executive Director Jim Kalkofen focuses on deep, main-lake points in the lakes he fishes across Minnesota and Wisconsin. "If there's deep cabbage available, it makes for an ideal point," he says. Kalkofen's program utilizes a combination of crankbait and jigging tactics to work deeper areas off points in depths ranging from about 15 to 30 feet.
"My favorite cold-front crank for pike was the big Rapala Risto Rap, sending it to bottom and bumping it off rocks. Other good baits are the Bagley DB06, Yo-Zuri Crystal Minnow Deep Diver, and Rapala Tail Dancer Deep. Run them near bottom, and also try cranks that work mid-depth zones for suspended fish. Long casts are best to get baits down to their effective working depths. Trolling is another good option.
"If I get a few hits on a crankbait and I know pike are in the area, I often switch to a jig-and-plastic combo," he says. "One of my favorites is a 3/8- to 1/2-ounce Northland Jungle Jig paired with a Berkley PowerBait 7-inch Ribbontail Worm. I cut the weedguard off the jig when fishing weedless areas. Another good setup is an Esox Cobra Head with a 71„2-inch Old BaySide Monster Mino Curltail from Lindy. I add a stinger treble by tying it with Tyger Wire to the bend on the jig's hook."
In lakes with traditional weed patterns, Straw finds that sunny, high-pressure conditions make for a tough bite, pushing inactive pike tighter into vegetation. "On a good day with clouds and wind, active fish are roaming weededges, and lures like spinnerbaits and swimbaits excel," he says. "If you're fishing a weedy bay, don't forget to make a some casts into the open water behind you. The bigger fish are moving, searching, feeding, and those casts often catch fish prowling open water.
"When a cold front moves in and conditions get tough, you have to think about changing your presentation to access fish that moved tighter into the vegetation," Straw explains. "That's when I switch to a jig-and-softbait combo, like a 5/8- to 1-ounce J-mac Musky Jig, but any quality weedless jig can be a good pike jig. Swim it and let if fall into pockets. The heavier jig also allows you to punch through thick weeds and pounce it on the fish."
In late summer into fall, Kalkofen fishes the deeper edges of weedlines when conditions are right, but during cold fronts he goes shallower. "Instead of fishing the 12- to 18-foot depths along mainlake weedlines, I fish farther up into the weeds. The inside weededge in 5- to 8-foot depths can be good for big fish," he says. "I like to use a spinnerbait, something with a big #7 Colorado blade that I can fish slowly, almost like I'm walking the bait under the surface. Let it drop into holes in the vegetation and work it through open lanes in the vegetation.
"Glidebaits and jerkbaits might be the best options for these conditions," Kalkofen says, "even though you typically wouldn't consider Reef Hawgs, Suicks, and Husky Jerks in weeds. But with a 71„2-foot heavy flippin' stick and 50- to 80-pound braid, you can rip them off when they hang up, which often triggers strikes. Rubber-skirted, bass-style jigs and plastics can be tremendous when swum over and through vegetation."
Like Pyzer, Straw observes the same wind-driven patterns for pike on Shield lakes. "On a nicer day, you find smallmouths on reefs topping out at 3 to 8 feet. Then add some rain and wind and the toothy monsters move in. There's something about 2- to 3-foot waves billowing over shoals and reefs that causes smallmouths to vacate and pike to move in. The 15- to 20-foot depths near the reefs that were good yesterday aren't so good today. Something about the waves is attracting active pike.
"It could be that shallow baitfish are disoriented and exposed because they're not able to hold in secure positions among the rocks, and the big animals aren't tossed around. I like to work suspending jerkbaits like a Rapala X-Rap under these conditions, getting it just deep enough under the effects of the wave troughs. Slash it, pause it, it's deadly."
It's no fun making the trek across the lake to reach spots in conditions like this, but once you're there, the fishing can be hot. But if conditions get too dangerous, this is no time to be out. You can catch pike just about anytime if you work hard enough, but certain times are better. How does it look? Partly pikey? Mostly pikey? Make a forecast and pick a pattern.