Michigan.gov Home DNR Home Links Contact DNR DNR Mobile Apps Site Map Search

Fishing

> Angler Information

>

Fisheries Management 

& Research

Wildlife Action Plan

Dams and Dam Removal

Fish Disease

Fish Ladders and Weirs

Habitat Management Unit

Marked and Tagged Fish

Research

Tribal Coordination Unit

> Fish Identification

> State Fish Hatcheries

About the DNR

Camping & Recreation

Commissions, Boards 

and Committees

Doing Business

Education & Outreach

Forests, Land & Water

Forms, Publications & 

Maps

Grants 

Hunting & Trapping

Law Enforcement

Licenses, Applications & 

Permits

Mackinac State Historic 

Parks

Michigan Historical 

Center

Wildlife & Habitat

 Printer Friendly Text Version Text Size 

Commercial Trapnets in Central Lake Huron

Since 2001, two commercial operations have been operating in central Lake Huron and DNRE has been working to 

avoid conflicts between user groups through communication. These two commercial fisheries usually fish a total of 17

trap nets between North Point of Thunder Bay and the Greenbush area south of Harrisville. The Alpena Fishery 

Research Station can provide interested anglers with coordinates for the current locations of these nets. Those 

interested in subscribing to these net location notices need to provide the Alpena Station with their e-mail addresses by 

contacting Jim Johnson at: 

Johnsonj2@michigan.gov 

Each commercial trapnet is marked with three staff buoys and black or orange flags. In addition to staff buoys, nets are 

also marked with several red, yellow, white, or orange floats that are at least two gallons in size. The nets are set deep 

enough to allow for recreational and commercial boat traffic to move freely at the surface but fishermen should be 

mindful of the net location to avoid loss of gear. Net locations are subject to change, thus boaters are urged to check for 

updated information. It may take several days for changes in net locations to be posted. Therefore, boaters should also 

be look carefully for trapnet bouys and staff that mark recently moved commercial fishing gear. 

 

The catch from trapnets is live when harvested and non- target species such as trout and salmon are released. 

Why trap nets?

In the late 1960s, the Michigan Natural Resources Commission issued orders that banned large-mesh gill nets and 

required replacement of gill nets with impoundment gear (trap nets). The intent of the ban was to "encourage 

conversion to the more selective, highly efficient, less damaging, trap nets, which were considered to be compatible with 

the goals of lake trout restoration" (Rybicki and Schneeberger, Recent history and management of the State-licensed 

commercial fishery for lake whitefish in the Michigan Waters of Lake Michigan. Michigan DNR, Fisheries Research 

Report No.1960, 1990). New York, Ohio, and Indiana banned the use of gill nets in 1994. Ontario and most tribal fishing 

authorities continue to authorize gill nets in their commercial fisheries. 

Gill nets, as their name implies, catch fish by entangling them in mesh, often in the gill area. Fish caught by the gills may 

suffocate or sustain irreversible damage to the gill arches including bleeding from the gills. At times, the fish are boxed 

with the net and removed from the mesh later; in these cases, mortality of the incidental (non-target) catch approaches 

100%. Trap nets work like aquatic corrals, capturing fish in large holding pens called "pots". Trap nets cause much 

lower mortality of the incidental catch and are efficient in the capture of lake whitefish - the principal target of Lake 

Huron's commercial fishery. Because the fish are live when taken from trap nets, nontarget fish such as trout and 

salmon can be safely released. Whitefish from trap nets (because they are fresher) usually sell for more than gill-netcaught whitefish. 

Michigan's State-licensed commercial fisheries on Lake Huron are required to release all trout, salmon, and walleyes. In 

Thunder Bay virtually all the harvest is composed of lake whitefish. A few carp, burbot, and channel catfish are 

occasionally also harvested. The whitefish catch can be purchased at a variety of stores and restaurants in the Alpena 

area. 

For more on the history and ecological considerations of trap net and gill net commercial gear, see the 

following publications: 

Johnson, J. E., M. P. Ebener, K. Gebhardt, and R. A. Bergstedt. 2004. Comparison of catch and lake trout bycatch in 

commercial trap nets and gill nets targeting lake whitefish in northern Lake Huron. Michigan Department of Natural 

Resources, Fisheries Research Report 2071, Ann Arbor. 

Abstract. - We compared seasonal lake whitefish catch rates, lake trout bycatch, and gear-induced lake trout mortality 

between commercial trapnets and gillnets in north-central Lake Huron. Onboard monitors recorded catches from 260 

gillnet and 96 trapnet lifts from October 1998 through December 1999. Catch rates for lake whitefish were highest in fall 

for both gear types, reflecting proximity of spawning sites to the study area. Lake whitefish catch rates were also 

Related Content

 • Lake Trout Hooking 

Mortality Study

 • Lake Invaders - the Fight 

for Lake Huron

 • Publications on trout and 

salmon of Lake Huron by 

Alpena Fishery Research 

Station

 • Status of Saginaw Bay 

Walleye Population and 

Progress Towards 

Recovery 

 • Cormorant Management 

Plans for Lake Huron 

2010

 • Changes in Lake Huron's 

ecosystem and foodweb 

lead to collapse of 

Chinook salmon

 • Alpena Fisheries 

Research Station Staff

 • Contact Information and 

Directions

 • History

DNR - Commercial Trapnets in Central Lake Huron Page 1 of 2

http://www.michigan.gov/dnr/0,1607,7-153-10364_52259_10951_11244-69487--,00.html 8/25/2011
relatively high in spring but low in both gear types in summer. Lake trout were the principal bycatch species in both 

gears. The lake trout bycatch was lowest in both gear types in fall, highest in gillnets in spring, and highest in trapnets in 

summer. The ratio of lake trout to legal whitefish (the target species) was highest in summer and lowest in fall in both 

gear types. The high lake trout ratio in summer was due principally to low catch rates of lake whitefish. All but 3 of 186 

live lake trout removed from trapnet pots survived for at least two days of observation in laboratory tanks. Therefore, we 

estimated that post-release survival of trapnetted lake trout that had not been entangled in the mesh was 98.4%. In 

addition, we accounted for stress-induced mortality for lake trout that were live at capture but entangled in the mesh of 

either gear type. Resulting estimates of lake trout survival were higher in trapnets (87.8%) than in gillnets (39.6%). The 

number of lake trout killed per lift was highest during summer in trapnets and during spring in gillnets. In trapnets, 85% 

of dead lake trout were observed to be entangled in the mesh of the pot or tunnels. Survival rates of lake trout in gillnets 

were higher in our study than reported by others, probably because our nets were hand lifted in a small boat. Our 

trapnet-induced mortality estimates on lake trout were higher than those reported by others because we adjusted our 

estimates to account for post-release mortality caused by handling and injury. Studies such as ours should prove useful

to managers developing harvest allocation options that are consistent with the need to protect nontarget populations. 

For example, applying our seasonal lake trout-whitefish catch ratios to a hypothetical small-boat gillnet fishery, the lake 

trout bycatch from harvest of 100,000 kg of whitefish would equal the estimated lake trout production available for 

harvest in the study area for year 2002. The two trapnet fisheries may have incidentally killed half this number of lake 

trout annually from 1995-1999. Bycatch estimates are also important inputs to catch-at-age decision models used in 

developing rehabilitation and harvest strategies for target and bycatch species. 

Johnson, J. E., J. Jonas, and J. P. Peck. 2004. Management of commercial fisheries bycatch, with emphasis on lake 

trout fisheries of the upper Great Lakes. Michigan Department of Natural Resources, Fisheries Research Report 2070, 

Ann Arbor. 

Abstract. - We investigated the collective published record on the significance and management of commercial fisheries 

bycatch at both global and Great Lakes regional scales to: 1) to identify elements of Great Lakes ecosystems that are 

especially vulnerable as fisheries bycatch; and 2) identify opportunities to minimize incidental catch of sensitive species 

in Great Lakes commercial fishing gear. The majority of the world's harvestable fisheries are fully- or over-exploited, and 

approximately a third of the global catch is composed of bycatch and discards. Bycatch can be characterized as the 

incidental catch of organisms that were not targeted in a given fishing effort. Significant levels of bycatch can contribute 

to overharvest. Therefore, it is essential to characterize bycatch when assessing impacts of fishing. Bycatch is not 

always measured; failure to measure bycatch can result in underestimation of fishing mortality and thus, overestimation 

of quotas available for harvest. Responsible fishing practices are being encouraged worldwide and most of these efforts 

have focused on reducing or eliminating the amount of bycatch associated with harvest of targeted species. The 

magnitude of the bycatch problem is typically proportional to fishing effort. In many cases, effort exceeds what is 

necessary to harvest sustainable yields of target species; thus, reduction of effort is often the single most effective tool 

in reducing bycatch. Other methods of managing bycatch include: development and use of more selective gear, 

prohibiting retention of bycatch, and use of incentives and penalties in quota management. Great Lakes fisheries have 

mirrored the global pattern of overfishing. Recovery programs for collapsed fish populations have necessitated 

restrictive harvest controls. Lake whitefish Coregonus clupeaformis populations have recovered, but lake trout 

Salvelinus namaycush are far from rehabilitated in lakes Ontario, Erie, Michigan, and Huron. Lake trout are the native 

keystone species of the upper Great Lakes, are the subject of immense rehabilitation efforts, and have vulnerability 

similar to lake whitefish to leading gear types used in Great Lakes commercial fisheries. Efforts to limit commercial 

fishing to more selective gear types have been only partially successful. Bycatch of lake trout in large-mesh gill nets set 

for lake whitefish has exceeded lake trout harvest quotas in some management units. The selectivity of gill nets is 

difficult to manipulate, especially when target and nontarget fish are of similar size and overlap in spatial distribution, as 

is the case with lake trout and lake whitefish. Trap nets are effective in catching lake whitefish and are less lethal to the 

catch than gill nets. Commercial bycatch, combined with targeted fishing for lake trout (recreational and commercial) 

and depredation by sea lampreys Petromyzon marinus, has contributed to the delayed rehabilitation of self-sustaining 

lake trout fisheries. Thus, we conclude that the widespread use of nonselective gear types such as gill nets in Great 

Lakes commercial fisheries is inappropriate in an era of shared resources and ecosystem-level rehabilitation efforts. 

 

Trapnet being lifted in Thunder Bay. 

Michigan.gov Home | DNR Home | Report All Poaching 1-800-292-7800 | Contact DNR | State Web Sites

Link Policy | Privacy Policy | Accessibility Policy | Security Policy | Michigan News | Michigan.gov Survey

Copyright © 2001-2011 State of Michigan

DNR - Commercial Trapnets in Central Lake Huron Page 2 of 2

http://www.michigan.gov/dnr/0,1607,7-153-10364_52259_10951_11244-69487--,00.html 8/25/2011