Redhorse Fish at Fauna Foundation

Redhorse: Life Below the Surface

The Redhorse Discovery

The constant, soothing sound of flowing water filled my ears as I patiently searched for migrating shorebirds along the banks of the Acadie River winding through the Fauna Nature Reserve this past May. Every now and then, however, an unusual splashing sound would interrupt the hypnotizing melody. As I curiously made my way to a higher vantage point to investigate, a chaotic scene of colliding silver and yellow reflections just below the water’s surface revealed itself to me. I had located a Redhorse spawning site!

Fauna Nature Reserve - Acadie River
The Acadie River

Redhorse in Quebec

The Richelieu river and its tributaries are home to five species of Redhorse freshwater fish, including the Silver Redhorse, Greater Redhorse, Shorthead Redhorse, Copper Redhorse and the River Redhorse. Although certain species’ ranges extend to other provinces and into the U.S., the Copper is found only in southwestern Quebec. Two species have special conservation statutes. The River Redhorse‘s status is considered to be of Special Concern by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), while the Copper Redhorse is listed as Endangered. Because all species are hard to differentiate visually, fishing for all species is prohibited in much of Quebec in order to protect these two species.

Aeriel view of fish swimming
Shorthead Redhorse spawn as seen from the bank.

The Shorthead Redhorse – A species to discover

After discussion with local scientists, the species that I observed spawning was confirmed to be the Shorthead species.

Redhorse Fish at Fauna Foundation

The Shorthead inhabits freshwater streams, lakes and rivers and is native to central and eastern North America, although its range is expanding. A fish that lives in the benthic zone (on or near the bottom), they feed mostly on invertebrates and plants. They are a prey species for Smallmouth Bass, Walleye, Northern Pike and the Muskellunge.

Fish tail underwater
A Smallmouth Bass, a predator of young Redhorse, swims amongst spawning Redhorse.

On average, they measure between 12 to 18 inches in length and weigh 2 to 3 lbs, although fish measuring up to 25 inches and weighing up to 6 pounds are not uncommon. In our cool, northern waters, Shorthead can live to be over 17 years old, in comparison to only 6 or 7 years on average in warmer climates.

Redhorse Fish at Fauna Foundation

Shorthead Spawn

Between March and June (depending on location), they migrate to shallow streams and rivers that have a swift current to spawn once the water temperature has warmed to between 8 and 16 degrees celsius. They spawn over gravel and rocky shoals near sand bars.

Redhorse Fish at Fauna Foundation
Redhorse stir up the gravel as they deposit their eggs.

Shorthead become sexually mature anywhere between the ages of two and six. Females produce between 18,000 and 44,000 eggs each during the spawn.

Redhorse Fish at Fauna Foundation

Watching dozens of these large fish congregating, interacting and stirring up the sediment in a reproductive frenzy was captivating to say the least. Not only was I delighted to find yet another species that utilizes our conservancy to reproduce, the discovery also raised many interesting questions (which we will explore in an upcoming post). We hope to study the spawn in more detail in the coming years, thus allowing researchers to learn more about this amazing freshwater fish species in the Acadie river.

Help maintain the Redhorse’s habitat at Fauna!