Photo courtesy of Eric Engbretson Specializing in Underwater Images of Live, Non-captive, Freshwater Gamefish in their Natural Habitat www.underwaterfishphotos.com

Bigmouth Buffalo like to live in lowland lakes, sloughs, and long rivers with slow to still waters. They prefer the above waters with a substrate of mud, silt, sand and gravel. During the warmer months you can find them in shallow bays, but they eventually move to the deeper parts of the lakes once the cold weather arrives.

There are only a couple of places in the province where they are found including Last Mountain Lake, the Assiniboine River and the Qu'Appelle River system. One will notice a feature on the Bigmouth Buffalo that separates it from all other suckers. Its mouth is not turned down and they do not have the large fleshy sucker-like lips, as do other members of the sucker family. They have a thick and deep body with huge scales surrounding their body, and are typically dark brown to bronze in color. The Bigmouth Buffalo is often mistaken for carp, but they can be readily distinguished by the absence of whisker-like barbells surrounding the mouth.

Aquatic Ecologist John Salamon holds up a Bigmouth Buffalo fish from the Qu'Appelle River system.

One would think that a fish of this size would have a healthy appetite. Big mouth buffalo have long gill rakers which allows it to strain aquatic invertebrates from the mud and water. As the fish swims, it inhales trapping all the food within the rakers, then exhales. What's a gill raker? Well if you look at the gills of a fish, the outside has a fleshy red filament appearance (See Figure 1). This is where the fish takes the oxygen out of the water to breath. On the inside of the gill is what they call the rakers. These collect food for the fish. The mouth structure of the Big Mouth Buffalo prevents the digestion of large food items such as fish.

The flow of fresh water from melting snow ignites the Bigmouth Buffalo spawning period in April or early May. The fish will move to rivers, flooded lakeshores and marshes. Dr. Jay Hatch, Associate Professor of Biological Sciences at the University of Minnesota, explains that the Bigmouth Buffalo has a very unusual spawning behavior. “They spawn in units of one female surrounded by two to four males; they move together through the shallow water in a series of "spawning rushes" evidenced by the ripples and splashes made by bodies and fins; the female sinks to the bottom and releases eggs, whereupon the males surround her and push her to the surface to start the whole thing over again.” Some biologists believe the "rush" or "tumbling" serves to mix eggs and sperm, increasing the likelihood of fertilization. Spawning is done in an orgy-like fashion in groups of 3-5 fish. The female is in the middle moving through the water creating ripples. As she releases her eggs the males move in to fertilize the eggs. This process is a very loud and sends water splashing everywhere.

A single female, depending upon size, can lay between 100,00 - 800,00 eggs. The fertilized eggs are normally sticky and stick to the first thing they touch - usually weeds. Once hatched, they are on their own and receive no care from the parents. The embryo's hatch in a couple of weeks and remain in the same shallows to feed and become bigger.

While not a threatened species, the Bigmouth Buffalo is particularly at risk because of low or declining numbers, and small habitat. The Bigmouth Buffalo faces threats from stream alterations and flood control measures. Siltation caused by shoreline disturbances will smother the eggs as well.