Fish are at their most vulnerable when they're spawning. Be it predators from above, such as eagles, otters, bears, or danger from below in the form or other fish, spawning trout, salmon, and char are forced to expose themselves during the critical spawning period in order to reproduce.
Most salmonids (trout, char, whitefish, grayling, salmon) reproduce in rivers and streams, though the time of year in which they spawn varies. Most of these fish usually look for similar river features to spawn in as well. Knowing a little bit about how and when trout spawn can make it easy to locate and fish to these exposed trout, but should you? Should you stay off the river entirely during spawning seasons?
The answers to those questions are complicated. If you know how to responsibly fish during spawning periods, you can absolutely fish year round without having much impact on future generations of fish, but it does require you to be mindful. Here are a few tips on how to fish responsibly during the spawn, as well as some general information about when trout spawn and in what type of water.
Don't Fish to Trout on Redds, Don't Walk on Redds
This is probably the easiest and most important pair of rules to follow when fishing during spawning season. Redds are areas in the river that trout of prepared for laying eggs. They are found in gravelly areas on the stream, typically in flatter water, and very often just above a hole or plunge. You will notice that redds have a lighter color to them than the surrounding areas on the river due to the fish fanning their tails to clean out the river bottom. Trout will stack up on these redds while the females lay eggs and the males fertilize them. Trout will be VERY aggressive while on the redds to protect the eggs and their spawning territory.
Walking across a redd can crush literally thousands of eggs and dislodge countless more. A dislodged egg has zero chance of hatching, and obviously the same is true of a crushed egg. If you have trouble identifying redds, only cross in rocky areas of the river; avoid gravel as much as possible.
Fishing to trout on their redds is also harmful, and many people (including us) will tell you it's unethical. Yes, these fish are highly susceptible, but catching one may ruin their efforts to spawn entirely. When you catch a female from a redd, the stress of the catch will cause her to immediately start dropping her eggs, a reflex action. While you're netting a fish, eggs dropped at this time will only end up drifting freely in the river. Males caught will also drop milt in the same sort of reaction. These fish will waste their reproductive abilities while you set them free.
During the spawn, other fish in the river will be extra aggressive. Fish, including very large fish that aren't actively spawning, will be in the river preparing to spawn or to feed on eggs in the drift. You can catch some amazing fish during the spawn while avoiding redds entirely. Fish deep holes, undercut banks, or shallow edges during the spawn, and give the actively spawning fish in the gravel runs a chance to do their thing. The fishery will be all the better for it.
Know When Certain Fish Spawn, Act Accordingly
Different species of trout spawn at different times of the year. Some trout will spawn in the spring through early summer (and even to mid-summer in higher elevations), while others will be on their redds starting in early fall through mid-winter. You can look below for the timing of spawns by type of trout, but realize that your elevation, water temperature, and local climate can affect those time periods.
In the spring and early summer, water can often be a little off color due to higher runoff conditions, so you really need to be careful where you step. Spotting a redd might be harder than it is in the fall, so pick your river crossing locations carefully. Never walk upstream nor downstream through the water during spawning season. If you need to change locations, walk along the banks.
In the fall, water levels are often low and the streams tend to have a slower flow to them. Water will also tend to be more clear, so use this to your advantage to identify redds before stepping into the water. With lower flows, try not to kick up mud and silt as you cross the river. Silt settling over eggs can be a death sentence. If you cross the river near a redd, it's always better to cross downstream than upstream of the redd.
As mentioned earlier, do everything you can not to catch fish on redds. If you know it's time for fish to be spawning, change your targeting technique to target another species or be careful not to pull fish from the redds and look for them in other spots on the river.
Release Fish as Quickly and Gently as Possible
You often catch more fish during the spawn than during any other time of year. Fish are naturally more aggressive while spawning or preparing to spawn. Even non-spawning fish will be more active and aggressive during these times of the year. Bending the barbs down on your hook will allow you to release fish easier, and you'll have your fly back in the water more quickly between catches.
When playing a fish, try to land it quickly. You can usually put more pressure on a fish than you think, and getting them to your net quickly will keep from exhausting the fish and hopefully keep females from dropping eggs and males from dropping milt. If taking pictures, keep it brief and try to get the fish turned loose in under 30 seconds from landing it. If possible, try to keep the fish out of water for under 10 seconds total. Have cameras ready, and lift the fish from the water only at the moment you take the picture. Always ensure a fish is properly revived before releasing it into the current.
Barbless hooks, nets, and a good hook remover will all reduce stress on the fish. Avoid dragging the fish across the ground, over rocks, or onto grass. The more you keep the fish in the water, the more likely it will be able to successfully spawn. Hold fish gently, and never squeeze them to keep them from flopping. A firm grip can easily damage a fish's internal organs or cause them stress.
Properly releasing fish, especially spawners, greatly reduces the negative impacts of fishing during spawning season.
Trout Spawning Seasons
As a basic rule of thumb, if it's fall or spring, it's spawning season for some species of trout, but whether or not trout are spawning where you're at depends on a few factors. Use this as a general reference, but know that it's a good idea to talk to your local Division of Wildlife Resources for more specific information.
When do Rainbow Trout Spawn?
Rainbow trout are spring spawning fish, and can start their spawn beginning in March and will continue through May. At high elevations, the spawn may start later than at low elevations and end later as well. Rainbow trout look for gravel-bottomed streams for their spawning grounds. Their redds can most often be found above holding water in shallow runs.
When do Cutthroat Trout Spawn?
Cutthroat trout are late spring to early summer spawning fish. Starting around late April, cutthroat will begin their spawn and can be found spawning into July. In coastal areas, some cutthroat have been observed spawning as early as February due to warmer water temperatures. Like rainbows, cutthroat trout look for gravelly riverbeds in shallow water to spawn. At times, late spawning rainbows may spawn with early spawning cutthroat, creating a cutbow hybrid offspring.
When do Golden Trout Spawn?
Golden trout are also a late spring spawning fish, from late April through mid to late June. Golden trout dig their redds in gravelly sections of streams and are most actively spawning during the warmer parts of the day.
When do Brown Trout Spawn?
Brown trout are fall spawning fish, usually starting in late September and running through mid-December. In the lower fall water, browns make their redds in gravel-bottomed runs and will often stage and hold in deep holes prior to spawning.
When do Brook Trout Spawn?
Brook trout spawn in the fall, from September through November in most cases. The brook trout spawn overlaps with brown trout often, but as a typically higher elevation fish, brookies will often start a little earlier. Like other salmonid species, brook trout prefer gravel-bottom runs for the location of their redds. Though rare, a hybrid cross between brook and brown trout may produce a tiger trout.
When do Bull Trout Spawn?
Bull trout also spawn in the fall, though their timing can vary a bit depending on whether they're found in spring-fed waters or runoff water. Typically, bull trout will begin their spawn in September and can be found spawning until late November or early December. Look for their redds in gravelly, flat sections of the streams. Bull trout are protected in most areas and fishing to them during the spawn and other times of the year is often illegal. Bull trout are highly migratory spawners, so finding them can be a challenge.
When do Dolly Varden Spawn?
Dolly Varden are also fall spawners, starting in early September and running through December. Some Alaskan dolly varden will be in full spawn coloring by early August. Look for dolly varden redds to be found in gravel sections of the river.
When do Lake Trout Spawn?
Like other char (brook trout, bull trout, dolly varden), lake trout are fall spawners and will be actively spawning from September through December. While most lake trout will spawn in rocky areas of their home lake, some can be found in streams as well, preferring gravelly river bottoms.
Knowing the times and locations that spawning is likely to occur can greatly improve your contributions to protecting fisheries. If you plan to fish during the spring or fall, always check with local regulations to see if certain sections of rivers are protected during spawning. Some rivers are outright closed to fishing during the spawn, while others may carry added restrictions. Do your part to help fish successfully spawn and ensure that each visit to the river is greeted with a good population of fish.