Lake information report

printer friendly version

Name: EMBARRASS MINE PIT

Nearest Town: 2 mi. W of Aurora
Primary County: St. Louis
Survey Date: 04/27/2005
Inventory Number: 69-0429-00

Public Access Information

Ownership Type Description
Minnesota DNR Concrete Township maintained boat launch on north-central side of pit with concrete ramp.
Other Unknown Walk-down unimproved accesses on east and south shores.


Lake Characteristics

Lake Area (acres): 156.00
Littoral Area (acres): 12.50
Maximum Depth (ft): 465.00
Water Clarity (ft): 24.00

Dominant Bottom Substrate: N/A
Abundance of Aquatic Plants: N/A
Maximum Depth of Plant Growth (ft): N/A


Did you know? Much of Minnesota's fisheries program is reimbursed by the Federal Aid in Sport Fish Restoration Program (federal excise tax), administered by the U.S. Fish and Wildlife Service.

Fish Sampled up to the 2005 Survey Year

Species

Gear Used

Number of fish per net

Average Fish Weight (lbs)

Normal Range (lbs)

Caught

Normal Range

Lake Trout Gill net 7.2 0.8 - 4.3 1.19 1.2 - 3.1
Rainbow Trout Gill net 0.8 N/A - N/A 1.12 N/A - N/A
White Sucker Gill net 1.8 1.7 - 5.0 1.29 1.6 - 2.4
Normal Ranges represent typical catches for lakes with similar physical and chemical characteristics.


Length of Selected Species Sampled for All Gear for the 2005 Survey Year

Species Number of fish caught in each category (inches)
0-5 6-8 9-11 12-14 15-19 20-24 25-29 30+ Total
Lake Trout 0 2 3 14 22 2 0 0 43
Rainbow Trout 0 0 0 5 0 0 0 0 5


For the record, the largest Rainbow Trout taken in Minnesota weighed 17 lbs., 6 oz. and was caught:

    Where: Knife River, Lake County
    When: 1/19/74
    Statistics: 36.9" length

Fish Stocking Activity

Fish Stocked by Species for the Last Ten Years

Year Species Size Number Pounds
2010 Brook Trout yearlings 1,600 235.3
2009 Rainbow Trout yearlings 1,550 574.1
2008 Brook Trout yearlings 1,534 639.1
2007 Brook Trout yearlings 1,550 553.6
2006 Rainbow Trout yearlings 1,550 580.5
2005 Brook Trout yearlings 1,550 620.0
2004 Rainbow Trout yearlings 1,551 470.0

Privately Stocked Fish
* indicates privately stocked fish. Private stocking includes fish purchased by the DNR for stocking and fish purchased and stocked by private citizens and sporting groups.

Stocking Fish Sizes
Fry - Newly hatched fish that are ready to be stocked usually called "swim-ups". Walleye fry are 1/3 of an inch or around 8 mm.
Fingerling - Fingerlings are one to six months old and can range from a size of one to twelve inches depending on the species. Walleye fingerlings range from three to eight inches each fall.
Yearling - Yearling fish are at least one year old. A one-year-old fish can range from three to twenty inches depending on the species. Walleye yearlings average from six to twelve inches.
Adult - Adult fish are fish that have reached maturity. Depending on the species, maturity can be reached at two years of age. Walleye reach maturity between the ages of four and six years.

Fish Consumption Guidelines

No fish consumption guidelines are available for this lake. For more information, see the "Fish Consumption Advice" pages at the Minnesota Department of Health.


Status of the Fishery (as of 04/27/2005)

The Embarrass Mine Pit (also known as Lake Mine) was a natural iron ore mine that was operated from 1943 through 1964. During its operation in the late 1940's the southern portion of Wynne Lake was filled in and the Embarrass River, which used to flow over the Embarrass Mine area, was diverted into a channel to the west. After abandonment, the mine was allowed to fill with water and in 1992 the water surface area was 156 acres and the maximum depth was 465 ft. There are no inlets or outlets to Embarrass Mine Pit. Mine walls are generally steep with sloughing gravel and dirt in areas. Aquatic vegetation is extremely limited.

Shallow water gillnet investigations in 1978 and 1983 showed that water quality was excellent and that white sucker, northern pike, walleye, and bluegill sunfish were present. All of these species had likely been stocked by the public. Trout stocking began in 1984, and included lake trout stockings in 1984 and 1985. Lake trout were not stocked after 1985. Since 1998, large (1/3 lb each) rainbow trout and brook trout yearlings have been stocked in alternate years.

The water quality observed on 04/28/2005 was similar to previous investigations on this lake. The water was very clear (Secchi = 24 ft), and quite hard (total alkalinity = 112 ppm). The surface temperature was 45 F and the temperature at the end of the probe cable at 150 ft was 39 F. Oxygen levels were greater than 8 ppm to the end of the probe. Previous investigations done later in the summer consistently showed oxygen levels above 6 ppm to depths of 150 ft.

The three shallow gillnets in 2005, set in depths of 8-21 ft, caught 23 lake trout, 5 rainbow trout, and 8 white sucker. The three deep gillnets, set in depths of 30-100 ft, caught 20 lake trout and 3 white sucker.

Lake trout sizes in shallow and deep gillnets were very similar, with average lengths of 15" in each depth range. The largest lake trout was 23.6". Nine of the eleven lake trout stomachs that were examined contained daphnia, while one contained unidentified invertebrates and one was empty. Ageing of lake trout by scales and otoliths differed dramatically. Otolith ageing was confirmed by Paul Hauck (Lake Superior Area ageing technician), and showed that the lake trout in Embarrass Mine Pit are quite old and growing extremely slow.

The rainbow trout were 13-14" and had been stocked as 9" yearlings the previous spring. All of the four rainbow trout stomachs that were examined contained daphnia, while one also contained caddisfly larvae.

Notable by their absence in this assessment were brook trout or rainbow trout older than the most recent rainbow stocking in 2004. Although none of the lake trout stomachs examined in this assessment contained trout, previous investigations and angler reports have found trout in the stomachs of lake trout and northern pike.

Recent angler reports indicate that mostly lake trout are caught. One angler who regularly fishes the lake said that many anglers take limits of just-stocked trout shortly after stocking each spring.


For more information on this lake, contact:

Area Fisheries Supervisor
650 Hwy 169
Tower, MN 55790
Phone: (218) 753-2580
Internet: Tower Fisheries
E-Mail: Tower.Fisheries@state.mn.us

Lake maps can be obtained from:

Minnesota Bookstore
660 Olive Street
St. Paul, MN 55155
(651) 297-3000 or (800) 657-3757
To order, use C0746 for the map-id.


For general DNR Information, contact:

DNR Information Center
500 Lafayette Road
St. Paul, MN 55155-4040
TDD: (651) 296-6157 or (888) MINNDNR
Internet: www.dnr.state.mn.us
E-Mail: info.dnr@state.mn.us

Tip Logo    Turn in Poachers (TIP):

    Toll-free: (800) 652-9093