But if their population is not carefully managed, they stand poised to become viewed as damaging pests. The otters are also accused of preying heavily on smallmouth and largemouth bass, goggle eye, catfish and suckers. Anglers fishing clear Ozark headwater streams are reporting a dramatic and rapid loss of keeper-sized fish and believe that otters are responsible. Anglers in other parts of the state have also complained about otter depredation. Anglers contend that river otters locate and prey upon the larger bass in headwater Ozark streams.
Adult fish are more vulnerable because they are larger and more lethargic.
For the most part, trappers have been on the sidelines of the otter controversy. Although they are concerned about any legal threat to trapping in Missouri, few trappers specifically target river otters. Missouri trappers primarily pursue raccoons or beaver, which are much more abundant. In fact, only about 400 to 600 trappers even catch a single otter in a year. Most otters are caught incidentally in traps set for raccoons and beavers.