1. Project Title: Stag Island Habitat Rehabilitation Project
2. Contact
Don Hector, Project Coordinator
Bret Colman, Project Facilitator
Ontario Ministry of Natural Resources (MNR), 1023 Richmond St. West,
Chatham, Ontario N7M 5J5
P.O. Box 1168 N7M 5L8
Tel. (519) 354-7340; FAX: (519) 354-0313
3. Agencies Involved
Great Lakes Cleanup Fund
Ducks Unlimited
U.S. Army Corps of Engineers
Lambton Industrial Society members
4. Restoration Goal
Phase 1
Wetland creation, enhancement and protection.
Phase 2
Upland rehabilitation.
Fisheries rehabilitation of the shallow waters surrounding the island.
5. Project Type
Phase 1
Alteration of the flow patterns of the wetland and offshore island
or breakwall construction to
protect the existing wetland.
Phase 2
Enhancement of upland through vegetation plantings (i.e., tall grass prairie and wildlife shrubs).
Fish spawning shoals in the shallows around the island.
6. Background and Rationale
The southern end of Stag Island was used as a dredge disposal site in the late 1960's and is now dry land with minimal coarse vegetation. The interior of the island contains a man-altered Class 3 wetland. Adjacent to the wetland is a possible candidate site for an "Old Growth Oak Forest " designation.
Sand bed-load moving with the river current has covered the river bottom off the northern point of the island, along the western shore extending south of the island several hundred metres. These sand shoals are considerable in width and at times extend 200 m west of the island. Water depths in the shoal areas range up to but seldom exceed 2 m. In some areas of the shoal, submergent aquatic vegetation such as Canadian waterweed has established. These areas of aquatic vegetation are mainly located in the calm backwaters and are not generally found within high flow areas.
The Class 3 wetland located towards the middle of the western shore is a series of dredge created spits and shallow water canals. Portions of the spits are inundated by water and afford good quality transitional wetland. The remainder of the spits offer higher upland that may be managed for waterfowl production. The entire wetland system has very shallow water with minimal boat access.
The southern portion of the island is owned by the Crown and is operated as the Stag Island Provincial Hunting Area. This area built up because of the now abandoned practice of dredge disposal from the St. Clair River which took place in the late 1960's. The southern tip is higher in elevation than the adjacent centre island wetland or the river water level. The shoreline is extremely erodible with a fairly steep bluff approximately 2-3 m in height. This portion of the island is largely composed of clay and sand and supports only coarse vegetation and a few small shrubs.
Stag Island presents an excellent opportunity to rehabilitate habitat in the upper reaches of the St. Clair River. This island shoal historically supported a large amount of wetland vegetation, particularly on the southern tip of the island. The objectives of the rehabilitation plan for Stag Island are; Phase (1) to protect and enhance the existing wetland for fish and wildlife production; and Phase (2) to re-create as much wetland as possible by creating calm water areas within the shallow waters of the island.
7. Regulatory Considerations
No approvals sought to date.
1. Environmental Assessment: Provincial Class EA Planning Procedure
Federal Environmental Assessment Review Process, because we were using federal funds (Environment Canada's Great Lakes Cleanup Fund);
2. Fisheries Act: approval necessary from Department of Fisheries and Oceans, this project should be deemed mitigable;
3. Navigable Waters Protection Act: approval from Canadian Coast Guard required;
4. Flood and Fill Regulations: SCRCA (St. Clair Region Conservation Authority) to review, future request for work permit;
5. Ministry of Culture, Tourism and Recreation: archeological concerns will have to be addressed.
8. Criteria
Not available.
9. Project Design
Phase 1
Technique
Increase edge area and water area in the canal complex by breaking the land ridges into a series of islands through mechanical excavation and deposition of spoils onto the new islands. Areas of existing land ridges which currently demonstrate wetland values would be left unaltered.
Benefit
Islands would increase edge effect and thereby add diversity in the canal complex. Water area would increase by approximately 25%. The newly created islands would provide waterfowl nesting areas and cover, as well as nesting and feeding areas for other birds.
Technique
Placement of logs, stumps and gabion rock shoals in the canals.
Benefit
Structure would add diversity to the existing open canals. Cover for fish would be provided as well as enhanced spawning areas. Exposed logs and stumps would act as loafing areas for waterfowl and turtles.
Technique
Placement of waterfowl nesting structures (i.e., nesting boxes and platforms.)
Benefit
Provide the nesting structures necessary to increase waterfowl production on this site.
Phase 2
Technique
Excavation of a pond system or a series of canals within hunting area.
Benefit
Waterfowl production, feeding and staging areas would be created.
Technique
Add topsoil to remainder of the area and plant with native tall grass prairie, shrubs and herbaceous plants.
Benefit
Provides cover, nesting and food production areas for small mammals, birds and herptiles.
Technique
Create walleye spawning shoals in the shallow shoal area south
of the island's southern tip using gabion stone unloaded from
a dump scow. An exposed rock berm, constructed convex to the
current, should be constructed on the upstream side of the shoal
to deflect bed-load around the spawning shoal.
Benefit
The shoal is presently devoid of structure and comprised of sand and small pebbles. Gabion stone shoals would provide walleye spawning areas.
Technique
Construction of an offshore breakwater in 2 m of water, west of the wetland area.
Benefit
A breakwater will reduce the impact of wakes and wind produced waves on shoreline structure and vegetation. A calm water area would be created, facilitating the accumulation of organic material and nutrients which in turn would promote the growth of aquatic vegetation. A breakwater would also provide physical structure for a fisheries food production area.
Technique
Placement of logs, stumps and gabion stone shoals in the calm water area east of the breakwater.
Benefit
Provide cover and spawning substrate for a variety of fish species.
10. Implementation
Material Selection:
1) Native seed sources only.
2) On site materials for construction with the exception of armourstone which will be brought in by barge from Amherstburg Quarry.
Models Used: HEC-2 model for the river to determine impact of islands/breakwaters and best design determination.
Engineers Drawings: Completed by the London Zone Office of the MNR and are available from the Project Facilitator.
Problems or Catches in Implementation: The Inland Boundary Waters Treaty of 1909 now being enforced.
11. Degree of Environmental Intervention
Excavation work will involve the use of backhoe and/or dragline. A barge will be used to deliver armourstone to the site. As the area slated for major construction is relatively sterile with respect to fish and wildlife occupation, environmental impact should be minimal. All excavated materials will be disposed of on site.
12. Cost
Phase 1 cost: $530 000
Phase 2 cost: $460 000
13. Biological Assessment
Monitoring:
A number of different techniques will be used to monitor the progress of the rehabilitation. These include the following:
1) Electrofishing (by boat and backpack) and seine netting to monitor changes in fish populations and diversity.
2) Monitoring nesting boxes to determine hatch success.
3) Monitoring or counting of amphibian calls in the spring of the year to determine diversity and population size estimates.
4) Plant inventories may be performed to determine the effects on the plant communities.
5) A re-evaluation of the wetland may be necessary to up grade the wetlands classification.
14. Measures of Success
Indicators include:
habitat area increase
species diversity increase
population size increase.
Success Rating: 1 - assessment incomplete
15. Key References
Ontario Ministry of Natural Resources, 1994 draft version of "Survey of Candidate Sites on the St. Clair and Detroit Rivers for Potential Habitat Rehabilitation/Enhancement".
OMNR/St. Clair River RAP/Rural Lambton Stewardship Network, 1994, "St. Clair/Sydenham River Regional Habitat Management Plan"
Correct citation for this contribution:
Hector, D., and Colman, B. 1995. Stag Island rehabilitation project, p. 171-175. In J.R.M. Kelso and J.H. Hartig [editors]. Methods of modifying habitat to benefit the Great Lakes ecosystem. CISTI (Can. Inst. Sci. Tech. Inf.) Occas. Pap. 1.