April's Featured WI Endangered Species: The Crystal Darter

My thoughts about the Crystal Darter:

No one knows much about the Crystal Darter (Crystallaria asprella). We don’t even know exactly how many Crystal Darters now exist, although we do know they have gone extinct in six states. In Wisconsin, Crystal Darters live in the lower Black, lower Trempealeau, lower Red Cedar Rivers and the Chippewa, Mississippi, St. Croix and Wisconsin rivers. They used to live in the Mississippi River basin from Wisconsin and Minnesota east to Ohio and south to Oklahoma, Louisiana, and Florida and on the Gulf slope in the Escambia, Mobile Bay, and Pearl River drainages. They were never common, but at least widely distributed. Now, they are extinct in Ohio, Indiana, Illinois, Tennessee, Kentucky, and Iowa. Because of their scarcity and the many threats to their existence from our degradation and destruction of their habitat, they are globally and nationally vulnerable, and endangered in Wisconsin.

1. What we do know about Crystal Darters is quite interesting:

A. Although they are part of the familiar Perch family, along with walleye, sauger and yellow perch, they are one of two darter species recently put into their own subgenera (they’re now called Crystallaria asprella) because of their “elongated shape, single anal spine, translucent flesh, and

B. their peculiar behavior of burying themselves in the sand”.The Crystal Darter’s unique behavior – burying in the sand, with only its eyes protruding…until prey comes along – is the most interesting to me. They are also mostly nocturnal, making their predatory strategy even more eerie and effective!

If you’d like to learn more, take a look at the Crystal Darter Status Assessment Report from 2003 by the US Fish and Wildlife Service, found at http://www.fws.gov/Midwest/Eco_Serv/soc/fish/crda-sa.pdf . Excellent maps and general information about the Crystal Darter can be found here: http://www.natureserve.org/explorer/servlet/NatureServe?sourceTemplate=tabular_report.wmt&loadTemplate=species_RptComprehensive.wmt&selectedReport=RptComprehensive.wmt&summaryView=tabular_report.wmt&elKey=100313&paging=home&save=true&startIndex=1&nextStartIndex=1&reset=false&offPageSelectedElKey=100313&offPageSelectedElType=species&offPageYesNo=true&post_processes=&radiobutton=radiobutton&selectedIndexes=100313 You can also find some information specifically about the WI Crystal Darter at http://www.dnr.state.wi.us/org/land/er/factsheets/fish/Crydrt.htm .

2. Threats to the Crystal Darter -- These include water pollutants from homes, agriculture, and industry as well as destruction and degradation of habitat through development, impoundment, channelization, dredging, and siltation. All river dwellers are vulnerable to these threats.

3. What is being done to protect the Crystal Darter?

In Colfax, WI residents voted to remove a dam in darter habitat.
The Lower WI State Riverway was formed by the WI legislature, in response to increased, uncontrolled development here. It seeks to preserve the aesthetic beauty of the region, from the Prairie du Sac dam to the Mississippi River, while respecting the rights of landowners, particularly those engaged in agriculture. See http://lwr.state.wi.us/ for more information.
The Lower Chippewa River Basin Partnership Team is a grassroots and government effort, in response to development pressures here. See http://basineducation.uwex.edu/lowerchip/index.htm as well as this report http://www.chippewariver.com/documents/2004MonitoringReport.pdf which tells us that despite this group’s efforts, there is much work left to do to keep these waters safe for people and wildlife.

5. What you can do to help protect the Crystal Darter --. Given the little we know, and how unusual the darter is from what we do know – what a great opportunity for those with a scientific bent to study the Crystal Darter, add something fascinating to our knowledge of the natural world, and hopefully save it from extinction!! If you live near these rivers, support dam removal and oppose development harmful to the Crystal Darter. If you own, work at, or know of farms and industry here, or if you live nearby, spread the word and act to eliminate harmful runoff! Vote accordingly!! Join and become active in local conservation groups!! Help save the Crystal Darter!!