By Nick Simonson

Water temperature is the driving force for many fish species in spring.  Not only as an impetus for  their annual spawning efforts but also impacting their activity levels being cold blooded creatures, as waters warm in the spring, fish become more active.  Considering water temperatures and the factors that influence their increase and monitoring those temperatures throughout the season can provide important hints to better fishing.

Foremost, each fish species has a preferred range of water temperatures to spawn in, ensuring the best survival of its eggs and progeny. Walleyes typically spawn when the water reaches 40 to 50 degrees, with the prime range being 48 to 54 degrees.  Pike have evolved to spawn at cooler temperatures, with most dropping their eggs when water hits 40 to 45 degrees.  Bass on the other hand, prefer warmer spring waters to spawn in, waiting until the temperature hits 55 to 65 degrees.  Through countless eons of evolution, these ranges have become springtime biological gospel which influences angling success.

Prior to each of these ranges settling in on a particular water, activity of those fish often increases as they forage and make their foray into their preferred nesting sites or those far upstream reaches where they will couple and beget the next generation of fish.  Noting the approach of spawn-worthy temperatures in a flow is a good way to know when fish will be biting ahead of the big event.  Take heed too of days with warm, sunny afternoons in spring which will likely trigger more activity later in the day as fish feed and continue gearing up for the spawn as warmer temperatures allow them more movement.

If you can’t be on the water with a thermometer in hand, or a lace-up one strapped into the boot of a favorite pair of waders, don’t worry!  There are plenty of online resources to help monitor water temperatures, especially on rivers.  The United States Geological Service has perhaps the nation’s best tracker of river conditions and water temperatures, with each survey site on a given flow tracking a variety of conditions (https://waterdata.usgs.gov/nwis/rt). While not every survey site will show temperature, a good number of sampling stations will. Most use Celsius as their data readout for water temperatures, so practice your conversion math (°C x 1.8 + 32 = °F). On longer flows, such as the Missouri River or the Red River, multiple stations can provide information on how water temperatures are changing downstream in spring, as water gets away from a cold discharge point such as a dam, or as runoff is added to the main flow.

Additionally, many resorts and angling-based businesses will keep tabs on springtime water temperatures in their reports to help visiting anglers prepare for the level of fish activity, so have a few set up to come through on your social media pages or via push notifications to keep tabs on those destinations.  Sometimes, however, it may come down to getting out there in the boat and using a sonar unit for your own sample or even doing it by hand and using a submersible thermometer to monitor conditions.

Weather factors in as well, with warm, sunny stretches or abnormally hot temperatures speeding things up, especially with a few days like that strung together in a stable span.  On the flip side, late-season snow or a cold rain can do the opposite and put the spawn on pause, just when it seemed things were about to fire up.  Monitor those conditions which affect water temperatures and the resulting fish behaviors to get a better bead on what the bite might be like.

Few springtime elements impact fishing more than water temperature.  Learning how that factor influences the behaviors of fish on a seasonal and day-to-day basis during the spring, and how to track it so you’ll be in the know is perhaps one of the best ways to stay ahead of the curve this time of year and catch more walleyes, pike, bass and whatever other species you might be pursuing as the water warms.

Simonson is the lead writer and editor of Dakota Edge Outdoors.

Featured Photo: Pike are some of the earliest fish to get active when spring waters warm, and will take to more aggressive baits and large flies ripped through the water before other species. Simonson Photo.