Michigan Sportsman Forum banner

1 - 3 of 3 Posts

1,688 Posts
Discussion Starter · #1 ·

December 6, 2005

To: All Fisheries Division Staff

From: Kelley Smith, Chief

Subject: Implementation of Chinook salmon stocking reductions on lakes Huron and Michigan

Over the past year, significant efforts were made to synthesize the fish community dynamics and ecology of lakes Huron and Michigan. Both Basin Teams and research staff at Alpena and Charlevoix, in collaboration with our lake agency partners, were challenged to address distinctly different scenarios in two of the largest freshwater lakes in the world. Lake Huron is experiencing dramatic changes in the balance between abundance of forage species and predator populations, which has resulted in large changes in Chinook salmon abundance and distribution. These changes have significantly reduced recreational angler harvest of Chinook salmon in the central and southern main basin of Lake Huron from the record high observed in 2002. At the same time, preliminary evidence suggests that Lake Michigan anglers have experienced yet another exceptionally high catch rate for Chinook salmon in 2005. The exceptional catch rates of the past few years have occurred even in the face of declining trends in the forage base in Lake Michigan. Long-term trend data on both lakes have indicated a need to alter stocking levels in an attempt to achieve a better balance between forage species and predators.

To meet the goals and objectives of the Department, the Division, the Joint Strategic Plan for Management of the Great Lakes Fisheries, and to address the desires of the angling community, the Lake Huron and Lake Michigan Basin Teams worked together to analyze and craft a scientifically sound, prudent, and reasonable management action for both lakes. The strategy was completed internally and in concert with the Lake Committees on both lakes, which encompasses three additional state jurisdictions, the Province of Ontario, and the Chippewa-Ottawa Resource Authority (CORA) representing the 1836 Tribes who are parties to the 2000 Consent Decree.

Throughout the process, public input was sought and incorporated at many different points in time. Several public meetings with anglers and other stakeholders were held in both basins starting in fall of 2004 for Lake Huron and spring 2005 for Lake Michigan. In addition, both Lakes’ Citizen Advisory Committee members were included and influential throughout the process. The Citizen Advisor Committees are led by our stakeholders and members of these committees represent angling groups and communities from throughout the basin. The Citizen Advisory Committees are to be applauded for their in-depth questions and participation in assisting our staff to arrive at reasonable solutions for future management of these lakes.

The management goals for each lake are very similar, but the biological and ecological information suggests a different approach to management strategies for each lake. Based on the management goals, a better balance between forage species and predators is desired to assist in native species recovery while maintaining economically and socially important fisheries. As such, modified stocking strategies for both lakes were crafted by the Basin Teams and Lake Committees, and have been accepted by the angling constituency. These strategies call for implementation in 2006 of reductions in the number of Chinook salmon stocked in Lake Huron by 50%, and by 25% in Lake Michigan. These lakewide strategic reductions are large enough to be measured statistically by our assessment programs, while providing an ongoing opportunity to readjust the predator-prey balance through stocking if future information suggests such a need. In the Division’s 40 year history of managing Pacific salmon in the Great Lakes, there has only been one previous lakewide reduction in stocking for each lake, both occurring in 1999. Thus, the current reduction plan is a significant event in the fishery management history of both lakes.

A key principle to understand and convey to stakeholders is that a reduction in stocking levels does not equate to reduced fishing success. In 1999, the Lake Huron Chinook salmon stocking level was reduced by 20% as supported by the stakeholders in spite of biological evidence that suggested a 40% reduction was required. Fishing success on Lake Huron remained exceptionally strong through the record year in 2002 and then began a decline to the lowest success recorded in 2004 since the inception of the creel survey program. Several events led to this decline as outlined in the Lake Huron briefing paper that was sent to Biologists in August. This paper can also be found on the Division internet site. In general, events leading to the decision to reduce stocking of Chinook salmon in Lake Huron included observations of significant reductions in prey biomass, a failed year class of alewife, an increased level of natural reproduction of Chinook salmon, and likely major changes in the lower levels of the food web.

Chinook salmon stocking in Lake Michigan was reduced by 27% in 1999 and the result was an increase in catch rate every year since. Fish Community Objectives outline the goal of maintaining fisheries with naturally produced fish, and if we have the opportunity to reduce stocking levels because of significant natural reproduction, it is reasonable to do so.

While the lakewide percent reduction is a strategic plan, tactical plans indicating locations for stocking Chinook salmon in both lakes were also required. Development of these plans was also accomplished with stakeholder input. The tactical plans for Michigan’s waters of lakes Huron and Michigan are attached for your reference. Again, please note that a reduction in any area is not meant to diminish the fishery available in that area. Specific site reductions, and especially those sites where stocking will be eliminated, were determined based on areas that have known significant natural reproduction.

If you have any questions regarding any of the tactics used, please speak with the Basin Coordinators or Management Unit supervisors for the lakes as they know the details behind each plan and can provide you with additional information. It is also important that this information is distributed and explained to our creel clerks as they represent the frontline with the stakeholders. It’s necessary that clerks who are uncomfortable with their knowledge of this information provide the correct contact for the individual to gain the information requested.

Becky Humphries
Mindy Koch
Dennis Fedewa
Dennis Fox

Talking Points for Tactical Reduction Plan for Lake Huron Chinook Salmon
Spring 2006

Key changes observed in Lake Huron:
• Changes in Chinook Salmon fishery- high catch rate 2002, low catch rate 2004-05
• Increasing consumption demands on forage
• Environmental conditions- harsh winters decrease alewife survival
• Food web disruption- exotic species tying up nutrients, less food for forage species
• Reduced condition of Chinook salmon

Key principles for management of Lake Huron:
• Lake Huron has productivity limits
• Strive to enhance wild reproduction
• Stocked fish play a role
• Ecosystem linkages are biological and physical
• Social and economic values are important to consider in making management decisions

MDNR objectives for stocking Chinook salmon in Lake Huron:
• Diversify and enhance the lake fishery
• Maintain prey levels that minimize negative effects on native species
• Provide for a return fishery
• Maintain brood stock return location

Why reduce Chinook salmon stocking levels by 50% in Lake Huron?
• Potential for measurable response
• Preserve return fisheries
• Reduce predation rates
• Provide compromise for social acceptance (all versus nothing in stocking levels)

Lake Huron Chinook Salmon Stocking Reduction Plan for Michigan
Location 2005 Target Net pen Final Target % Reduction
St. Marys River 80,000 N 0 100
Nunns Creek 250,000 N 250,000 0
St. Ignace 80,000 N 40,000 50
Cheboygan 150,000 Y 67,000 55
Swan River1 737,000 N 472,000 36
Mill Creek Pond (Harrisville) 250,000 Y 111,000 55
Van Etten River 500,000 Y 223,000 55
Tawas 60,000 N 27,000 55
Au Gres River 60,000 N 0 100
Port Austin 160,000 N 72,000 55
Harbor Beach 80,000 Y 80,000 0
Harbor Beach 320,000 N 80,000 75
Port Sanilac 80,000 N 36,000 55
Lexington 80,000 N 36,000 55
Total 2,887,000 1,494,000
1This location may implement net pens and thus the actual number stocked may vary based on a 2:1 survival rate for smolts stocked from a net pen versus direct stocking. If net pens are implemented, the actual number stocked in Swan River will decrease.

Shaded gray lines are locations covered by the 2000 Consent Decree.

Talking Points for Tactical Reduction Plan for Lake Michigan Chinook Salmon
Spring 2006

Key changes observed in Lake Michigan:
• Chinook Salmon Fishery- record catch rate 2004, most likely 2005
• Increasing consumption demands on forage
• Forage levels at all time lows through 2004
• Alewife condition reduced
• Weight and ration for age 3+ Chinook salmon continuing to trend downward
• Food web disruption- exotic species tying up nutrients in the lake
• Wild recruitment increasing

Key principles for management of Lake Michigan:
• Lake Michigan has productivity limits
• Enhance wild reproduction of native and introduced species
• Stocked fish play a key role in management
• Ecosystem linkages are biological and physical
• Preserve native fish
• Social and economic values are important to consider in making management decisions

Objectives for stocking salmonids in Lake Michigan:
• Maintain the diverse lake fishery
• Maintain salmonid catch rates
• Promote lake trout rehabilitation
• Maintain prey levels that minimize negative effects on native species
• Minimize disease outbreaks
• Provide for a return fishery
• Maintain brood stock supply
• Reduce reliance on stocking

Why reduce Chinook salmon stocking levels by 25% in Lake Michigan?
• Reduce predation rates on forage and promotes balance
• Potential for measurable response
• Maintain diversity of species
• Proactive management action using best available information

Lake Michigan Chinook Salmon Stocking Reduction Plan for Michigan
Location 2005 Target Net pen/ pond Final target % reduction
Ford River 40,000 N 27,500 31
LBDN-Gladstone 10,000 N 10,000 0
LBDN-Escanaba 11,000 N 11,000 0
Manistique River 54,475 N 45,000 17
Medusa Cr. Imprint pond 298,087 Y 220,000 26
Kids Cr.-Boardman River 235,332 N 150,000 36
Manistee River 98,055 Y 70,000 29
L. Manistee River 9 mile 490,275 N 375,000 24
Portage Lake 49,028 N 0 100
Big Sable River 156,888 Y 120,000 24
Muskegon River Henning Park 47,083 N 0 100
Muskegon River Outlet 50,000 N 30,000 40
Muskegon River 50,000 Y 30,000 40
Grand River Riverside Park 137,745 N 75,000 46
Grand River Marina net pen 200,000 Y 175,000 13
Macatawa River1 54,475 N 45,000 17
Kalamazoo River1 54,475 N 45,000 17
Black River S. Haven 52,296 Y 45,000 14
St. Joseph River 150,000 Y 100,000 33
St. Joseph River Arden 37,394 Y 20,000 47
Total 2,276,608 1,593,500
1These two sites start new net pens in 2006.

9,792 Posts
Under conditions I think the right thing is being done.Thanks for posting info here.Talk about harsh winters having an affect on baitfish survival?It doesnt look good for this up coming next year.Its not even officialy winter yet :tdo12: Lets hope for the best.
1 - 3 of 3 Posts