Beaver dams and brook trout

General trout, fishing, conservation, or anything outdoors related discussion. Trip reports and stream conditions welcome, but please do not name streams.
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PicketPin
Posts: 41
Joined: Wed Jan 06, 2016 9:53 pm
Location: Lanesboro

Beaver dams and brook trout

Post by PicketPin »

Bemidji State researchers have been looking at the revival of beaver populations on North Shore streams, what the increased dam-building means for brook trout and whether the DNR should remove dams or leave them alone. The work was featured last year on Prairie Sportsman https://video.pioneer.org/video/beavers ... ut-yrz9pp/. Preliminary findings are being presented Wednesday in Duluth. Below are the abstract and poster sent out by the Arrowhead Flyfishers.
Title: Effect of beaver on brook trout habitat in North Shore, Lake Superior streams.
Abstract-Brook trout provide a valued and productive sport fishery to the North Shore streams of Lake Superior and since revival of the beaver population from past trapping and timber harvest, a need emerges to examine the complex ecological relationship where the two taxa interact. Suitable brook trout habitat is characterized by cold, spring-fed water with silt-free rocky substrate and abundant cover, all of which beaver may directly, or indirectly, affect. To begin casting light on the beaver and brook trout relationship in the region, data was collected in a 200-meter stream reach during July and August, the hottest months with the lowest flow. Sampling occurred in 79 stream sites and 21 beaver ponds during 2017 and 2018. Brook trout habitat variables measured throughout each stream site included stream velocity, depth, temperature, and substrate. These measurements allowed me to quantify the amount of suitable brook trout habitat in each site sampled. In addition to sampling brook trout streams, you could also find me paddling along transects in a float tube in beaver ponds. In beaver ponds, variables such as dissolved oxygen, pH, and temperature were measured. Using GIS and aerial photos, I also measured beaver variables that I thought might potentially be affecting brook trout habitat. Preliminary results of my research indicated that higher quality brook trout habitat was found in sites with a greater stream length. Preliminary results also indicated that there was suitable brook trout habitat (sometimes even better habitat than was calculated in any of the streams) in 13 of the 21 beaver ponds sampled. Since the effect of beaver on brook trout varies regionally, the goal of this study is to aid in the development of management strategies pertaining to these two species in North Shore, Lake Superior streams.
Renik poster APRIL 2019.jpg

High Stick
Posts: 139
Joined: Sat Dec 09, 2017 6:19 am
Location: Driftless and The West

Re: Beaver dams and brook trout

Post by High Stick »

From a southern Driftless angle, I have seen quite a few beaver dams, houses, and general tree cutting from them quite a bit more the past couple of years. No fur market certainly aids in their population growth.
Last edited by High Stick on Tue Apr 23, 2019 7:55 am, edited 1 time in total.

darklake
Posts: 108
Joined: Tue Apr 05, 2011 8:54 am

Re: Beaver dams and brook trout

Post by darklake »

Katti spoke at our TU chapter meeting last year (Bemidji) and was very interesting and engaging. The extent of the work she has been doing on the north shore is remarkable. Well worth it to stop by and hear her presentation.

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