One critical component to successful fly-fishing is acquiring basic knowledge of aquatic entomology in the area is advised before you get your waders on.

The “hatch” is a period of time in which the various insects (trout food) in a particular area are experiencing their life cycle, buzzing about, luring the trout to rise in the waters for dinner. Most often, when anglers mention “hatch” they mean the moment when insects rise to the surface and become adults, which is also known as “emergence.” However, hatch activity can also include bugs flying around above water, skimming on the surface, or crawling on rocks underwater.

Several hatches can occur at the same time. At times, an angler can catch a few, find the best match in their flybox, and be successful. At other times, the trout may be highly selective, and a catch may require changing the fly to a more alluring size, color, or species.

Hatches on the Upper Rio Grande include midge, caddis, terrestrial, stone fly, and mayfly hatches. Keep in mind that Mother Nature can change her mind anytime. Unusual weather and draught conditions tend to contribute to irregular hatches. Click on the links below for more information on each hatch.

• Midge

  The moniker “midge” refers to several families of two-winged insects that include midges, flies, mosquitoes, and gnats. For simplicity’s sake, many consider any small fly on the water a midge.

  Starting around the first of April, the midge action begins and will usually run through the middle of October. They typically appear in large swarms most often during the evening.

  Midge larvae emerging from the eggs are often found in silt, mud, or dense vegetation at the bottom of streams, rivers, and lakes and can be any color. Midge pupae form from these larvae—some via cocoon, but not all—and begin to enlarge, rising occasionally to just below the surface.

  Pupae emerging to their adult form are of particular interest to trout and angler alike. At this time, there is some struggle as the insect rises to the surface to shed its pupal skin, making easy prey for trout. This midge on the brink of adulthood is most commonly known as a “surface emerger.”

  JH Specials and Dead Chickens are Broadacres Ranch guide favorites during this hatch. Consult our guides and visit our on-site fly shop, the Wooly Bugger, to learn more and stock your fly box for the midge hatch.

• Caddis

  Adult caddis flies are small, moth-like insects. Given their inability to survive in polluted waters, they indicate areas of high water quality. Caddis are often considered a trout’s very favorite meal and therefore imitation of them is a valuable skill for any angler.

  The main caddis hatch in our area usually begins around July 1st and lasts through the end of August. Sporadic hatches do occur throughout the rest of the year. Caddis larvae hatch from eggs and crawl on the bottom of streams, rivers, and lakes. Once they emerge from their casing and become pupae, they often crawl on the bottom waiting for good hatching conditions, at which time they swim to the surface to become adults. This is a key time for anglers to imitate, as the caddis is most vulnerable at this time.

  Adult caddis flies can be found on the water when they are hatching, letting their wings dry, or returning to the water to lay their eggs. They often “skim” the water during this process.

  Elk Wing Caddis, Metallic Caddis Emergers, and Goddard Caddis are Broadacres Ranch guide favorites during this hatch. Consult our guides and visit our on-site fly shop, the Wooly Bugger, to learn more and stock your fly box for the caddis hatch.

• Terrestrial

  “Terrestrials” include grasshoppers, crickets, beetles, and ants. Terrestrial hatches in this area typically occur from the first part of June to late September.

  Terrestrial insects are not aquatic but tend to spend a lot of time in the meadows and banks surrounding bodies of water. Due to wind, hanging on a tree a little to close to the water, or a clumsy jump, many of them end up trout food.

  Watch (and listen) for non-aquatic insect action nearby. Simply imitating their behavior with a terrestrial pattern can be fruitful; i.e., plopping a grasshopper imitation onto the water near the bank as if it had just been blown in.

  Joe’s Hoppers, Fleetle Beetles, and Black Ants are Broadacres Ranch guide favorites during this hatch. Consult our guides and visit our on-site fly shop, the Wooly Bugger, to learn more and stock your fly box for the terrestrial hatch.

• Stonefly

  Area stoneflies range from very tiny to “giant” (3”-4”) and from black to golden to dark brown to pink. The hatch is relatively short-lived in our area, lasting only several weeks from mid-June to the end of July.

  Stonefly nymphs are distinctive and large. Depending on their size, stonefly nymphs can live up to three years. This immature phase compromises the majority of their life. Unlike many other aquatic insects, stoneflies have no pupal or larval stage. They emerge directly from nymph to adult stage, which can last from a few days to a few weeks depending on size.

  Emergence typically occurs around dusk or even after dark as many stoneflies are nocturnal. Nymph action can occur weeks before the first adults emerge and nymph migration may continue well into the main emergence.

  Both stages of the life of a stonefly provide a good part of a trout’s diet. Special attention should be paid to nymphs as they begin to migrate towards the shore, drawing bottom-feeding trout right up to the banks.

  Stimulators, Improved Sofa Pillows, and Rogue Foam Stones are Broadacres Ranch guide favorites during this hatch. Consult our guides and visit our on-site fly shop, the Wooly Bugger, to learn more and stock your fly box for the stonefly hatch.

• Mayfly

  Several species, including the pale morning dun, blue-wing olive, green drake, and light cahill, are included in the mayfly family. Mayflies are the most diverse category of aquatic insect.

  Mayfly nymphs emerge directly to adults, then experience an intermediate dun stage and a reproductive spinner stage before death. The mayfly will usually begin emerging around the first part of July until the end of August. On the Upper Rio Grande, emergence usually takes place when the water is warmest in the early afternoon.

  Mayflies appear the most appetizing to trout during four times: when they are preparing to emerge (mayflies often become restless and swim frantically under the surface), when they get stuck in film on the surface, as they wait for their wings to dry on the water’s surface, and when the female returns to the water preparing to lay her eggs.

  Pale Morning Duns, Green Drakes, and Hex Spinners are Broadacres Ranch guide favorites during this hatch. Consult our guides and visit our on-site fly shop, the Wooly Bugger, to learn more and stock your fly box for the mayfly hatch.