White Sucker

Scientific Names: Catostomus commersonii

Common Names: White Sucker

White Suckers are commonly confused with Longnose Suckers, which are related as bottom-feeding fish. Both use fleshy lips to suck up organic material from the beds of rivers and streams as food and look very similar. The main difference between the two is that the longnose sucker has grey or dark, olive-colored sides.

Instead of being used as food for humans, White Suckers commonly are used as bait for bigger and more prized game fish. This occurs when they are still small and appear similar to minnows. If they are eaten by humans, they are normally processed and sold as mullets.

When they are younger and smaller, White Suckers are preyed on by Northern Pike, Muskellunge, Bass, Walleyes and Atlantic Salmon.

White Suckers reproduce in shallow waters and are believed to be influenced by changes in water temperature to begin the process. This can be caused by runoff from early snow melt or other factors. Females of the species lay near 10,000 eggs and it is not uncommon for them to be fertilized by multiple males.

White Sucker Interesting Facts

White Suckers are sexually mature between 4 to 9 years of age;
they can survive in urban waterways without difficulty and are tolerant of turbid waters;
fully grown White Suckers can reach 12 to 20 inches in length;
the fish prefer to search for food in warm, shallow waters;
and White Suckers grow most efficiently in conditions that are 19 to 26 degrees Celsius.

White Sucker Distribution and Identification

White Suckers can be found throughout the northeast and midwest United States. They can also be found in portions of the upper northwest. They survive in rivers, streams and most any other type of water body.

HUC_Dispersal_Map_-_Catostomus_commersonii

Map of White Sucker distribution across the United States. (Credit: U.S. Geological Survey)

White Suckers have long, round bodies with light-colored underbellies and darker-colored sides, usually splashed with a dark green, grey, copper or black. Their fins are rayed in a similar fashion to other cypriniform fishes, like carp and chub.

White Sucker Biology

Studies into the fish have focused on its life cycle, including reproductive abilities, how White Suckers use their habitats and what types of prey they prefer.

A 2010 study, overseen by the University of Wyoming, found that White Suckers readily hybridized with Bluehead Suckers and Flannelmouth Suckers in order to survive in a stream they weren’t native to.

A study from the U.S. EPA found that the fish’s growth is affected by temperature changes of water. Levels of low light are also advantageous to the fish’s development, with better growth rates seen in White Suckers who had been exposed to low light rather than no light at all.

Researchers at North Dakota State University found in 2011 that White Suckers have a size-selective approach to eating. The fish tend to pass up small organisms, instead going for larger prey.

References Cited