May 10, 2021
By Jim Gronaw
I have passionately studied bluegill behavior for several decades, from farm ponds to reservoirs of various sizes, to tidal rivers and beyond, and I've taken copious notes over the years on when they spawn and when they move out of the shallows. Over time, it's become clear to me that on the majority of waters, the largest bluegills in any given system prefer to spawn deeper than the smaller, rank-and-file fish that typically measure 7 inches or less.
Of course, this "deep water" is relative and varies from one water body to another. "Deep" in a farm pond might be close to 4 feet, whereas a much larger reservoir with clear water could see fish bedding as deep as 8 feet.
While many anglers will stalk the shallows this spring and make respectable catches of bedding bream, chances are they'll miss out on the biggest bluegills in the lake.
DEEP SPAWNING SITES
Several factors can determine bluegill spawning depth, the most important of which is suitable bottom content for fanning the beds. If the water is clear, you'll likely find dark, adult, bedding males seeking deeper haunts. Turbid or off-color water doesn't mean that fish won't bed deeper, it's just that they won't be visible with the aid of polarized glasses, and then sonar comes into play. Not every lake, pond or river is the same, and some waters may have a limited area of deeper water that is ideal for spawning.
Water level fluctuations can also throw a wrench in the movements of deeper bedding bluegills, triggering both deep and shallower travel to find and utilize the best available spawning substrate. But, given the option, large, adult bluegills that meet or exceed the 10-inch mark, will seek deeper water during the spawn.
Deeper water offers numerous benefits for spawning fish. For one, deep spawners are not vulnerable to predation from birds of prey. Second, they don't suffer stymied spawning efforts due to late-spring cold fronts that drop the shallows several degrees colder than what is ideal for reproduction. Deeper waters, even at the 4-foot depth, hold their temperature, and ripe, adult females will hook-up with like-sized males for the spawn.
When a big chill hits, shallow-spawning bluegills can shut down quickly and may vacate the area. Sadly, ripe females might not even deposit their eggs at all, leaving a void in that year class of quality offspring.
Thirdly, angler harvest—and overharvest—is always greater with shallow, more visible fish.
Locating deep spawners can be challenging, but it's certainly not impossible. Todays' side-scan sonar units can clearly depict those crater-like beds, and the better models can even show fish on individual nests.
On larger reservoirs look for bedding areas on and around long, tapering points or throughout gradual flats in 3 to 8 feet of water that are adjacent to 8- to 10-foot depths. Again, the bottom substrate of fine gravel or a sand/gravel mixture is paramount to draw and hold bluegills during the reproduction process. Additionally, if there are brush piles or weed beds near these colonies, the location could be better yet, as bluegill fry need nursery areas to hide and forage during their first year of life.
During low-water periods in late summer or fall, spawning colonies are often exposed and easy for the angler to spot. I often utilize Google Earth to zoom in on bars, points and flats during drawdown periods to find huge bedding areas that are otherwise under 4 feet of water in spring. Additionally, satellite images that show lighter shading out away from the shorelines can be a telltale giveaway for large colonies of big bluegills.
Keep in mind that deep water doesn't have to be far away from shore. Deep water is relative, and in most spawning scenarios the larger bluegills bed deeper, and sooner, than the rank-and-file smaller fish that make up the bulk of most populations. Frequently, when those easy-to-find 'gills are in thin water, it's a tip-off that bigger, better bluegills are not far away and several feet deeper.
GETTING DOWN THERE
Many of my best trophy bluegill fisheries are small and are best fished with a kayak, or even from shore or by wading. Still, going deep almost always gets the biggest spawning fish. For this type of fishing, I prefer two methods: the float-and-fly and the drop-shot.
The float-and-fly concept isn't new, yet remains as good as it gets for covering water and delicately presenting bait and lure options to deeper, bedding 'gills. When I locate bedding fish in waters from 3 to 8 feet deep, I like to suspend my offering 6 to 12 inches above the bottom so the bait is literally in the fish's face. If the 'gills are at 4 feet, I use a fixed float with a 3-foot drop. For those as deep as 8 feet, I'll set the float at 7 feet and rig baits accordingly depending on the bottom, or spawning, depth. This way, my jig or live worm will remain at point-blank range in front of the fish. A 5 to 10 mph wind helps cover the bedding colony as the surface chop gently pushes the bobber along. The wave action also imparts movement to your bait that can be enticing to spawning 'gills.
Oftentimes you can catch more fish by raising the bait higher off the bottom, thus provoking active, aggressive guardian males that are scurrying about the bedding colony in a frenzied manner. However, cold front conditions often force fish to literally hunker down right in the bottom of the nest itself. These neutral to inactive fish seldom move far or chase a lure or bait, so it's important to drift an offering just a few inches off the bottom to get their attention.
My lure of choice is a 1/64-ounce hair jig or a plain 1/32-ounce ball-head jig that is tipped with either a small garden worm, meal worm or live cricket. The ball-head jigs should be painted white, chartreuse or orange to attract the attention of the fish, and the live bait seals the deal if the gills are picky. On tough days a size 8 Aberdeen hook and a live redworm, earthworm or time-honored cricket can outproduce the jig options.
I opt for Gamma Poly Flex in 4-pound test or Trout Magnet SOS Monofilament in green for this technique. Bobbers and floats are traditionally a personal choice among southern panfish anglers. However, they should be small enough to just suspend the baits.
Fluorescent orange- and chartreuse-colored floats aid in strike detection. However, active, spawning fish usually take the float right down. I prefer ultralight spinning gear, but use longer 7- to 9-foot rods to aid in casting distance (especially when wading or in a kayak) and for setting hooks in deeper water.
The drop-shot method involves simply working a baited size 8 Aberdeen hook with the previously mentioned worm and cricket options and a 1/4-ounce teardrop sinker throughout the colony and setting the hook when the rod tip telegraphs the tap of a bluegill bite.
For most drop-shot efforts, a 12-inch drop from the hook to the weight on the bottom will catch fish as you slowly drift or retrieve your baited hook on the outskirts of or through the colony.
A lift-drop retrieve works well some days while a simple drag on the bottom catches more fish on others. This method, sometimes referred to as "tight-lining," is especially effective on bedding redear sunfish, or shellcrackers, as sometimes they mix with spawning bluegills in many waters throughout the South.
Indeed, spotting and catching visible bluegills in 18 inches of water can be fun and fast. But, more often than not, bigger bluegills and sunfish are not that far away, and in depths of several feet rather than inches.
Humminbird’s Solix with side imaging pinpoints bedding fish in deep water.
Locating bluegill beds in stained, tannic and/or deep water is nearly impossible with the naked eye. Advances in sonar technology now offer anglers a live, peripheral picture from their boat. This technology, called side imaging, provides anglers a unique window into their underwater surroundings.
Humminbird’s Solix sonar unit ($2,199-$2,499; humminbird.com) is particularly useful for finding deep-water bluegill beds. The Solix, with its MEGA Side Imaging, is three times more powerful than other models in its class, providing side-image views out to 200 feet on each side of the boat.
To locate deep-water bluegill beds, the operator need only idle in areas and at depths where he suspects bluegills are bedding. The unit’s built-in topography maps allow users to narrow their search for candidate bedding areas. Beds appear clearly on the screen, looking much like craters on the moon’s surface. In most cases, the unit will provide enough detail to show the actual fish residing on their beds.
The Solix has a convenient touchscreen and is simple to operate. A keypad is also included for those who prefer such an interface. An all-in-one transducer transmits down- as well as side-imaging information back to the unit to reduce transom clutter. — Dr. Todd A. Kuhn