Return of river otters cause for hope
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This past summer I had the good fortune to observe North American river otters in Illinois on three separate occasions, more than I ever have before in a single season. The most memorable of these was when two otter pups splashed through a pool I was fishing on the Middle Fork of the Vermilion River early one morning. Their mother soon followed, but she had lost sight of them and she climbed out onto the opposite bank to look around, calling as she did in a series of bird-like chirps. (I was able to get a little video clip of the mother because I had gotten out my point-and-shoot camera as the went by.)
What’s so remarkable about seeing otters in Illinois?
It was only five years ago that they were removed from the list of state threatened species. At that time their population was deemed to be widespread and secure based on estimates that there were 4,600 otters living in areas where they had been reintroduced by the Illinois Department of Natural Resources.
The longer history of otters in Illinois is marked by dramatic ups and downs.
At the time of European settlement, river otters were common throughout state, but their numbers declined steeply during the nineteenth century, due to habitat loss and unregulated hunting and trapping. By the beginning of the twentieth century, sightings of river otters were rare, and when the species was listed as state endangered in 1989 it is estimated that there were fewer than a hundred living in the state.
How did we get from fewer than one hundred otters to where we are now? Conditions for otters in Illinois had become favorable again even when numbers were at their lowest. Pollution in state waters had been greatly diminished thanks to the Clean Water Act, and that had allowed populations of fish, the otter’s main food, to rebound. In addition, beavers had come back in the state. Otters favor abandoned beaver dens for housing, and they also take advantage of the pools and wetlands beavers create for fishing.
Given these conditions, all the Department of Natural Resources had to do was just add otters. Between 1994 and 1997 a total of 346 otters that had been trapped in Louisiana were released in appropriate habitat throughout Illinois. The robust growth in their numbers affirms that these animals found everything they needed to make themselves at home. Besides multiplying so quickly, they surprised biologists by taking up residence even in highly developed landscapes, including the Chicago area.
If you’re familiar with river otters, you know they are fascinating creatures. Strong, graceful swimmers, they are capable of remaining under water for three to four minutes, and traveling as much as a quarter of a mile in that time. In winter they bound through the snow and then slide on their bellies. Otters are also both curious and nearsighted, which is part of an adaptation that allows them to see well underwater, and which also explains why they sometimes come very near people and boats to investigate them.
The successful reintroduction of river otters in Illinois will allow more and more people an opportunity to see them in years to come, and that’s cause for celebration. More importantly, though, it’s cause for hope, a reminder that even when conditions are bleak, good public policy, such as the Clean Water Act, can open the way for environmental renewal.
Environmental Almanac
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