Invasive Species

Big Mantrap Lake confirmed its first Aquatic Invasive Species in the form of Eurasion Water Milfoil in June of 2020. While it is unfortunate there are many more and far worse invasives creeping steadily closer. We maintain a commitment to helping stop the spread of further invasives into Mantrap as well as the spread of Milfoil out. We continue to support some of the most inspection hours of any lake in the county.

We encourage residents to keep eyes on the water in the late summer for any matting vegetation and report it to the Lake Association Board Members if anything looks suspicious. A picture is worth a thousand words!

Further information about the 2020 discovery of Eurasion Milfoil can be found here: Eurasion Watermilfoil Confirmed in Big Mantrap Lake

Please help us in our efforts by pulling drainplugs and cleaning your boat on your way in and out of any lake.

MN DNR Invasive Species Information

Eurasian Watermilfoil Identification Card

AIS & Native Plant Identification Guidebook

Lake Water Quality

The 2017 Summary for Big Mantrap Lake water quality can be found here. 

Big Mantrap Lake is an active member of the Hubbard County Coalition of Lake Associations

Shoreline Management

The Minnesota DNR has several documents available on shoreline ownership and best practices. A good example can be found here.

Rules regarding the removal of aquatic vegetation from shorelines including dock and open water access can be found here.

Fishery Status

General information on the lake, as well as fishery status, can be obtained from the Minnesota DNR's LakeFinder page here. 

We also have some presentations from the DNR on our NEWS page.

Fishing Regulations

Big Mantrap Lake falls within the newly established "North-Central Zone", however the lake has a more limited Northern Pike harvest as well as a specific crappie limit.

• Black & White Crappie: Possession limit five

• Northern Pike: All from 24-36" must be immediately released. Possession limit three, only one over 36"

• Muskellunge (statewide): Possession limit 1, minimum size 54"

2021 Minnesota Fishing Regulations Guide

Watercraft Safety & Regulations

Big Mantrap Lake's unique features and geography require that boaters be aware of certain areas and state laws when it comes to watercraft operation.  Mantrap Lake depth varies greatly, though mid-summer lack of emergent weeds generally indicates safe depths for motors.  Higher traffic channels are marked with buoys. 

• There are two no wake zones (<5mph)

• Some loon nesting areas are marked to allow safe distance

In addition these statewide regulations apply particularly:

• It is illegal to operate a watercraft in a careless or reckless manner.

• It is illegal to operate a watercraft within an area legally marked off as a swimming area

• It is illegal to chase wildlife with a motorboat, or operate a boat where it is prohibited - including marked spawning beds. Avoid traversing any emergent or floating vegetation, if possible.

• Personal watercraft must travel at slow no-wake speed (5mph or less) within 150 feet of nonmotorized boats, shore (unless launching or landing skiers directly to or from open water), docks, swim rafts, swimmers, or any moored or anchored boat.

The full Minnesota DNR Boating Guide and be found here.