Invasive Species

[papadarv]

When was the last time you heard anyone rant and rave about Eurasian Water Milfoil? Introduced to MN in 1987 and through the 90’s, we complained, complained, blamed the DNR, cried that this invasive weed was going to kill off many fish because the invasive plant overtook native vegetation. DNR, lake associations and others monitored lake assesses for years to prevent transfer to no avail. Were creatures of habit and don’t like change. And NO Eurasians Water Milfoil did not kill off all the fish, as lots of fish still are caught along the much easier defined weed lines. Of the 388 DNR reported infested lakes only 20 new lakes were added in the last year and ½ and no longer seen to be an issue.

Now we have a Zebra Mussel invasion, introduced to MN in 1995 with the same, rant & rave as was with the EW Milfoil, fostered by the DNR and news media with all the negative effects. They will eat all the Zooplankton fish food, large attachments to solid objects, sharp shells on bottom cutting swimmers feet etc. What we hear little about Zebras each adult filters 1 quart of water daily eating algae, a single cell plant Phytoplankton, including the toxic Blue-Green algae which for years been known to kill fish, dogs and humans. A female can produce a million eggs annually so the spread in infested lakes is rapid. Within a couple years the green, brown lakes are clear promoting vegetation growth to deeper water providing more cover for smaller fish. It ticks us fishing people off because our fishing techniques used for the last 50 years no longer work as fish feeding habits change. For us avid fishing people we will learn the new fish feeding habits on infested lakes rather quickly while occasional fishers may never learn new techniques which will increase fish population. While Zebras filter vast amount of algae they secrete a highly nutrient feces on the lake bottom providing a smorgasbord for bottom feeders including many of the minnows and other bait we use. After 4 to 5 years a large number of zebra die as their algae food supply is depleted.

Hang in there, 465 bodies of MN waters already infected with Zebras with70 in 2019/2020. Infestation will continue as most boat access will not be monitored and the vast majority of boaters could care less about prevention. Another infestation will most likely happen and we will no longer focus on Zebras. Just a thought.

The first excel file is the DNR link to all infestations. Second file Eurasian milfoil and Zebra lakes

 

https://files.dnr.state.mn.us/eco/invasives/infested-waters.xlsx

 

Zebra-Eurasion infested.xlsx

 

[BobT]

Regarding Eurasian Water Milfoil, last I heard bass fisherman love it. Regarding zebras, I have said all along that while it may be true that they will flourish after introduction to a new lake, they will eventually find an equilibrium based on the food supply in the lake. Osakis was infected a few years ago. Just a couple weeks ago I was talking with one of the lake shore owners and asked him what he has seen. He said at first, the zebra muscles were all over his docks and boat lifts in the fall when he pulled them out of the lake, however, for the past couple years they have not been so thick. In fact, last fall when he pulled out his docks he counted seven muscles attached. I have also heard reports that fish and other aquatic animals have now begun feeding on zebras. One species in particular that I've heard mentioned is sunfish. Maybe the lakes will have too many jumbo sunfish now? 

[h8go4s]

Mussels. Not muscles. I'm a spelling specialist.

[BobT]

22 hours ago, h8go4s said:

Mussels. Not muscles. I'm a spelling specialist.

Thanks for the correction. Really, I'm not being sarcastic. I usually do a better job than that. I'm not perfect but spelling, punctuation, and grammar are important to me as well. 

Edited August 10, 2020 by BobT