Unusually high oxygen levels in Brainerd-area rearing ponds could diminish walleye fingerling production next fall. DNR Fisheries Supervisor Tim Brastrup said he's dismayed by the oxygen readings he's found in area rearing ponds.
"They're the highest we've ever seen at this time of year," Brastrup said, "and it will likely impact the amount of walleyes we can produce next fall. We have oxygen all the way down to the mud. We've never seen that before."
Too much oxygen in rearing ponds is harmful. The DNR counts on winterkill each year to eliminate bullheads, minnows and leftover walleye stock from the previous spring. If oxygen levels remain high these undesirable fish live into spring and feed on newly-stocked walleye and compete with them for food, resulting in fewer walleyes to stock next fall.
High oxygen levels occur during mild winters with little snow and sunny days. Photosynthesis -- a process in which plants produce oxygen from sunlight -- occurs in these conditions. Oxygen in a small pond allows pond fish to survive.
The DNR had hoped to create winterkill conditions with a process called reverse aeration. Air is pumped into a pond and the layer of oxygen-depleted water is forced to circulate throughout the pond. This year, however, there is too much oxygen to consider reverse aeration, Knapp said.
DNR fisheries biologist to speak at club meeting
Mark Cook, a DNR fisheries biologist in Bemidji, will present "70 years of angling and its effect on fishing" at the March 13 meeting of the Pelican Lake Conservation Club.
Born and raised in Minnesota, Cook is a life-long fisherman who received a bachelors degree from the University of Minnesota and a Masters degree from Colorado State. His articles on fisheries research have been published in several professional journals.
The Pelican Lake Conservation Club is located off County Road 4 one mile south of the Breezy Point Resort entrance. Social hour begins at 5:30 p.m. and dinner is at 6 p.m. There is no charge for dinner, but space is limited to the first 80 people who sign up by March 11. Phone any of the following numbers: (218) 562-4117, 562-4553, 963-7942 or 562-4512.
Youth turkey hunt proposed by NWTF, DNR
The Minnesota Chapter of the National Wild Turkey Federation is exploring with the DNR the concept of a special youth turkey hunt.
Hunting would be allowed only on private land during the open season. Youths would have mentors from Wild Turkey Federation chapters. Participation would be limited to youths who had not been drawn for regular hunts. Mentors would be allowed to assist without a license but would not be allowed to shoot. Before they could take part in the special hunt, youths would need to participate in a clinic sponsored by NWTF and have completed a firearms safety course.
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