Though sunfish move into shallow water with the first rising water temperatures of spring, they delay spawning until morning water temperatures are close to 70°F. Afternoon temperatures into the 70°F range aren't enough. Warmer water must persist through the night to bring on the sunfish spawn.
This requirement for warm water seems related to the diet of bluegills for most of their first year — zooplankton. Several weeks of elevated temperatures and sunlight are necessary to get the food web in high gear.
First, planktonic algae must multiply in surface waters. This food supply for minute animals allow Daphnia, copepods, and other key critters to bloom, in turn providing fodder for the transparent little 'gills. When spring warming is sporadic or early summer brings cool, cloudy weather, poor bluegill hatches usually follow, leaving weak or even missing year classes.
Appropriate conditions may occur as early as late February or early March in south Florida. The peak of the initial spawn occurs progressively later at higher latitudes, though coastal areas tend to warm faster and higher elevations remain cool longer. In central Ontario, northern Minnesota, and Maine — the northernmost portion of the bluegill's range — spawning may not begin until mid-June and may last into early July.
Also, in more southerly waters, bluegills may spawn several times over the course of a summer, even into late September in the Gulf Coast states. Northern waters support only one spawn period, though it may be protracted over a month or so, as fish of different sizes and ages mature, and as windy, cold weather sometimes -drives fish from the beds; they resume spawning when conditions improve.
Bluegills are among the most social of fish species, nesting in large colonies. Scan the water while running your trolling motor on high, looking for nesting colonies that resemble the skin of a golf ball.
Bluegills tend to construct their round nests on shallow flats protected from pounding waves and current. Males seek the inside corners of bays, dead-end creeks, and shorelines with high banks that block prevailing winds.
They favor substrates of medium hardness for nesting, like mixtures of sand with some silt or gravel, material that can be shaped into the lipped divots that males are able to protect. Marl also functions well in hard-water systems.
Many bottoms with a sand base have, however, been covered by layers of silt from bank erosion or from organic layers left behind as aquatic plants decay each year. Male bluegills sweep off this layer, producing light nests against a dark background.
Where sand and gravel are scarce, harder objects on the bottom offer spawning sites for smaller groups of fish. Lily pad rhizomes and mussel beds attract spawners in Florida, while in Minnesota, 'gills may choose to nest on stands of wild rice or maidencane, where the root systems form a mat. These spots aren't ideal and typically occur where bluegills are scarce. Colonies will be small (a couple dozen or fewer fish) and widely separated, though individual fish may be large.
Boat Versus Boot: In most waters, a boat aids in searching for bedding bluegills. A keen-eyed observer can spot nests as the boat idles through shallow bays and over flats. In the shallowest bays, a small jonboat, kayak, or canoe is able to scull along in just inches of water, easily parting emergent grasses that often hide beds. In these conditions, this approach is easier and more efficient than a big trolling motor ripping up weeds and stirring the bottom.
In any case, the boat's just a platform for fishing once 'gills are found. A more secure platform is better, so set an anchor, or two in windy conditions, to keep yourself pinned in place.
If bottom content is solid enough, wading is a great way to work large bedding areas. And in ponds, walking the bank or wading calf deep allows for carefully and precisely working beds.
If bluegill nesting colonies are small and widely spaced, which is often the case in large lakes and reservoirs, wading is less practical. But scouting by boat may reveal more beds so you can secure the boat and proceed on foot.
If the bottom is moderately soft, be alert for especially soft spots that can dump you. Also, avoid kicking up silt that will drift over the fish. The resulting cloud will kill the bite for the hour or so it may take to clear. But where practical, wading with a long rod or pole and carrying a small box of baits in your vest is an exciting and effective way to catch spawners.
Rod Versus Pole: Your next decision is whether to use a rod or a pole. Long poles are highly functional for reaching out to place a bait in a spot, often one that can't be cast to because it lies behind a clump of reeds or a tree limb. And the length of the pole (usually 10 to 20 feet) lets you remain beyond the spook zone, so long as you don't create a scary shadow.
Poles help drop a bait silently, the way a hatching fly falls into a pond. And once you learn the feel and balance of your pole, flicking the bait can be extremely accurate, unlike casting a small bait or float rig on a spinning rod. And because a pole allows for the element of surprise, you can use a heavier line than would work on a spinning rod.
The heavy line also helps hoist a big 'gill from cover and provides a fighting chance if a bass or bull crappie sucks in your offering. Once you have the fish's head up, you can pull him over the top of weeds or stickups.
Most commercial crappie poles run from 8 to 15 feet long, and European graphite poles can measure up to 30 feet, yet telescope into a 3-foot butt section for storage and transportation. Cane poles usually are cut about 18 feet long and can be shortened by trimming the base.
Most times, small floats complement pole fishing by suspending the bait some distance above bream beds. The fish are active, circling and chasing, and though they'll take a bait off the bottom, one suspended above generally does better. A float, whether a slip or set model, allows for easily adjusting the depth the bait hangs.
Some anglers prefer spinning rods, through tradition or because poles are admittedly heavy and can be frustrating to maneuver around tall emergent grass or stickups. At times, too, you may want to remain farther back from a bedding bluegill colony than a pole allows. Skittish fish in clear water less that two feet deep can present such a challenge.
Seven-foot medium-light-power spinning rods are comfortable to fish and cast with reasonable accuracy. A reel with a medium or larger spool diameter allows longer casts and keeps line less coiled than a tiny reel. Rig with a small float or a casting bubble like the Rainbow Plastics A-Just-A-Bubble, a versatile tool for hunting spring 'gills.
The bubble easily adjusts for distance above the bait and provides the weight to send a tiny offering off like a rocket. Choose the smallest size for use with 4- or 6-pound-test line; it creates less splash and moves more sensitively when supporting the lightest jig or a small livebait.
Livebait Versus Fakebait: In most situations, as many panfish can be caught with a crafty piece of plastic as with a live worm, minnow, or leech. Careful choice of plastic, jig shape and weight, and attention to lure action can usually put all the 'gills you want in the boat in summer, fall, winter, and early spring.
But when 'gills are on beds, there are times when lively leeches can mean the difference between picking off a few aggressive males or lurking females, and targeting the biggest males in the colony.
I often use plastics as a search bait or to test the mood of the bluegill throng. Leech imitations, tiny tubes, and twister tails all draw strikes when worked through bedding areas. Experiment to determine if fish want a bait sitting still, falling slowly, or drifting horizontally across the beds. And at times they pick a bait off the bottom.
But spawning bluegills can be mighty picky, swimming up to a bait and inspecting it before turning away. Or they take it momentarily into their mouths, then blow it out as you start to set the hook. That's when the leeches come out. Their undulating action is hard to pass up. In southern waters where leeches aren't available, a small gob of redworms or a cricket may do as well. Garden worms and nightcrawlers work, too, but seem to attract more small sunfish.
When the Bite Sours: Sometimes fickle spring weather throws bluegills and bluegill anglers a curve. Falling water temperatures may cause the sunfish to delay their spawn, and if a severe front strikes in the midst of bedding activity, the fish pull out to deeper warmer water to wait until conditions reverse. This common situation makes fishing tough, because sunfish have receded beyond our visual depth, and they're skittish and unaggressive.
There's an antidote for these conditions, one worth keeping in mind any time unfavorable weather pushes 'gills from the shallows. Rig a 5-foot ultralight rod with limp 2-pound-test mono and a tiny ant-style icefly backed with a single waxworm. In these negative conditions, they seem to prefer a drifting bait. It's tough to present, but merely get the bait into the water and let the buoyancy of the worm keep the lure falling slowly. At times, your line simply starts to straighten; sometimes you see a flash in the water as a fish emerges and engulfs the morsel. It's no-feel fishing at its finest.
In most states, length limits don't exist and bag limits are generous. Conscientious anglers who find colonies of large bedding bluegills must harvest them selectively. Release all the largest males, which could be from 8 to 10 or more inches, depending on the system. Fish scoot right back into the group. Keep a moderate stringer of eating-size fish, including females and smaller males, and then move on. Resist the urge to take those 10-inchers home.
Bluegill Spawn Scenario
When water temperatures reach 65°F, bluegills begin moving into locations near potential spawning areas. Groups remain scattered across flats, holding near clumps of weedcover.
With stable weather and warming water, bluegills push shallower, looking for areas of favored bottom type — fine sand mixed with some gravel or moderate silt. Even when potential spawning sites are abundant, social bluegills establish nest sites adjacent to each other.
As water temperatures approach 70°F, females stage in slightly deeper water near nesting colonies. Males have begun to clear nests with side-to-side tail undulations. They sweep out fine sediments, leaving larger particles to build a firm, lipped nest, ranging from 2 to 6 inches deep and 8 to 24 inches in diameter. One hundred or more nests may be built side by side in an area.
Spawning occurs at a range of water temperatures from 68° to 85° or more, but it typically peaks in early summer at around 75°F. Males have attained a brilliant coloration — dark head, sharp lateral bars, and deep orange or red chests — to attract females.
After a short courtship, a female moves from the side of the male and tilts her body parallel to the bottom of the nest, quivering as she releases a few dozen eggs, each about 1/16 inch in diameter. The male immediately fertilizes them and chases the female off the nest. She may soon return and spawn again, often with another male.
After releasing their eggs, females move somewhat deeper, seeking cover in beds of aquatic vegetation or in timber. They begin feeding on aquatic invertebrates to regain a good condition after the spawn.
Males continue to protect their clutch, fanning them to maintain oxygen and disperse waste products. Eggs hatch in 2 to 3 days when temperatures are in the mid-70°F range.
After hatching, males guard their fry from the many predators that linger around spawning colonies, looking for a meal. Fry absorb the energy supply of their yolk sac for over a week, then move off the nest to hunt small zooplankton.