Average phosphorus level (1996-1999) was 0.009 mg/L
Water quality considered to be good for lake trout
Crow Lake is a moderately sensitive cold water fishery
Lake depth allows for high reserves of dissolved oxygen in the bottom waters, but may reach minimum acceptable levels for lake trout in the summer months
Every effort should be taken to protect remaining lake trout habitat of Crow Lake
Practices that decrease nutrient and sediment loading should be strictly followed (ie. shoreline buffers, restrict livestock access, monitor cottage septic systems, etc)
Many shoreline rehabilitation sites exist in the north portion of Crow Lake. Within the village of Crow Lake, several cottages and waterfront homes exhibit hardened shorelines. Cement break-walls and docks are present with many of these sites lacking riparian vegetation (Figure 2.3.5)
Critical Fish Habitat
Lake Trout- eight spawning shoals exist these include: Gull shoal, the Bobs/Crow Lake channel, the eastern shoreline, the shoreline near Campbell’s Cottages, and a small location near the southwest shore (Figure 2.3.5)
Additional enhancement is needed for the southwestern shore of the Bobs/Crow Lake channel and Gull shoal.
Lake / Watercourse
Fish Community Objective
Existing Fish Habitat Conditions
Fish Habitat Enhancement Opportunities
T3 – Crow Lake
Cold water community with top predators such as lake trout, walleye, smallmouth bass, and northern pike
All populations are natural and self-sustaining
Critical Fish Habitat,
Lake Trout spawning shoals have been created on Green (Idyle) and Snake islands, and on the southwest shore.
Walleye- six main walleye spawning sites exist on Crow Lake (Figure 2.3.5) these include: the Crow Lake dock, Crow Lake village creek, Scott’s Creek, the Bobs/Crow Lakes channel, Snake Island, and a small area near the southeastern shoreline
Walleye spawning shoal rehab. completed on Crow Lake village creek and the northeastern shore of the Bobs/Crow Lake channel.
Bass- Smallmouth bass and largemouth bass spawn in isolated, sandy near shore areas around the lake (Figure 2.3.5), main areas include the Crow Lake dock, the main lake point, near the island on the western shore, south of the mouth of Scott’s Creek, and the mouth of the channel
Northern Pike- one known spawning area exists at an inlet creek within the southern back bay in the east shore of the lake
Enhancement work should focus on Scott’s Creek and the southwestern shore of the Bobs/Crow Lake channel
Bass nesting and rearing areas should be protected from in or near water development, and early summer angling. Continuing education of anglers regarding earlier bass fishing by re-establishing the distribution of flyers and signs on illegal bass fishing to resorts and others.
Northern Pike spawning and nursery areas require protection from near shore development and water level manipulations
Priority Enhancement Projects:
T3 – Bobs Lake, Green Bay
Lake Trout Spawning Shoal Enhancement
As previously mentioned several small islands currently provide limited lake trout spawning habitat (Figure 2.3.1). Although lake trout have not been observed spawning near these sites, the areas are wind swept/exposed islands near relatively deep water with appropriate substrate; characteristics common to lake trout spawning shoals in various Ontario lake trout lakes. Presently, areas of cobble to rubble sized rock exist on some portions of the island shoreline. To increase their potential as spawning shoals, rounded, well washed limestone cobble ranging in size from 5-30cm should be placed over non-suitable spawning substrate (ie. flat rock areas). This limestone cobble should be placed in wide bands up onto the shoreline extending down to 4-5m in depth (depending on water levels). By placing rock in this manner, appropriate substrate will be supplied to lake trout regardless of water levels during the spawning and incubation periods.
In lakes subject to water level fluctuations, lake trout and other fish species have been known to spawn at greater depths. Two small under water structures (humps) located in Green Bay (Figure 2.3.1, refer to Appendix 3 for UTM coordinates) present opportunities to create lake trout spawning habitat at greater depth. These sites are totally submerged from approximately 0.5m to 3m of water. Appropriate spawning substrate is sparse at the first site and may function as a small lake whitefish and cisco spawning site. The second site is a bedrock shelf located in approximately 3m of water. No fish species are thought to utilize this habitat. To enhance both sites rounded limestone cobble ranging in diameter from 5-30cm should be placed around the entire site. This enhancement will supply spawning habitat for lake trout and other species in deeper water, totally protected from drawdown effects. By enhancing these locations with appropriate substrate, spawning habitat will be offered at greater and varying depths. In addition, these locations will attract prey species, and double as feeding reefs.
3.Shoreline Rehabilitation In order to improve or maintain (at minimum) the existing highly sensitive lake trout habitat of Green Bay, shoreline rehabilitation should be conducted. The majority of rehabilitation sites are located in the northern, most heavily developed region of Green Bay (Figure 2.3.1). Many cottage lots require replanting of natural shoreline vegetation such as red-osier dogwood (Cornus stolonifera), shrubby willow (Salex sp.), meadowsweet (Spiraea alba), and Virginia creeper (Parthenocissus vitacea) to decrease sediment and nutrient loading. Interested property owners can obtain assistance and funding from MAPLE or CFWIP. Limiting shoreline development should also continue in order to maintain quality Lake Trout habitat.
Fish Creek (Figure 2.3.2) is regarded as one of the best walleye spawning beds in the sub-watershed. According to local knowledge Fish Creek requires a clean-up project to remove vehicles and waste within the creek channel near the village of Bobs Lake. The spawning bed could be extended and enhanced by placing rounded, well washed rock cobble, ranging in size from 8-35cm in diameter.
2. Bobs and Crow Lake Channel Walleye Spawning Shoal Rehabilitation The Bobs and Crow Lake channel (Figure 2.3.2, Figure 2.3.5) is another highly utilized walleye spawning site. This location is used by walleye from Bobs Lake and Crow Lake as well. Enhancement work has already taken place on the northeast side of the channel, with walleye observed spawning on the enhancement project. Further enhancement should be managed as a lake trout enhancement using well washed limestone rounded cobble 5-30cm in diameter placed on the southwest shore of the channel.
3.The Portage Cut Walleye Spawning Shoal Rehabilitation The Portage Cut (Figure 2.3.2) located along the eastern shoreline of Crow Bay- Bobs Lake. This area is currently utilized by spawning walleye from Bobs Lake. The western side of the Portage Cut is adjacent to existing walleye spawning locations on the eastern shoreline of Crow Bay. This side of the Portage Cut would be suitable for enhancement with well washed rounded 8-35cm diameter rock cobble. Presently the area is composed of bedrock and larger rock unsuitable for successful egg incubation. Since the shoal is adjacent to existing walleye spawning locations, enhancement of this shoal will have greater chance of success.
Thompson’s Creek Walleye and Pike Spawning Area Enhancement
Thompson’s Creek (Figure 2.3.3) flows into Long Bay from its headwaters of Lynn Lake. This creek was believed to be a prime walleye and northern pike spawning area until the installation of a small culvert under a cottage access road crossing. The improper installation of this culvert blocked the migration of walleye and northern pike to their respective spawning areas above the road crossing. In approximately 1995, a bridge was built to allow access to spawning areas in a six foot wide access point provided by the bridge. The project was sponsored by OMNR-Kemptville District and the Greater Bobs & Crow Lakes Association. Seeding is considered a positive enhancement for this area.
Bobs Lake Livestock Restriction
Two large areas of cattle access to water exist at the south end of Mill Bay and on the western shore near the Bobs Lake outlet (Figure 2.3.3, refer to photo). There is also cattle access to Long Bay at Thompson’s Creek. Cattle should be fenced out from accessing the water in these locations to prevent water quality degradation and alternative-watering sources such as nose pumps should be explored.
Riparian vegetation should be restored on cottage lots in the West Basin, the entrance to Mud Bay, in Buck Bay, Long Bay, and the above pasture/ cattle access sites. These locations should be replanted with low growing species such as red-osier dogwood (Cornus stolonifera), shrubby willow (Salex sp.), meadowsweet (Spiraea alba), or Virginia creeper (Parthenocissus vitacea) to anchor nutrients/sediments and prevent water quality degradation
T3 – Crow Lake
Crow Lake Lake Trout Spawning Shoal Rehabilitation
Lake trout naturally reproduce near many locations in Crow Lake with some of these locations already enhanced. Two spawning shoals have been created on Green (Idyle) and Snake islands (Figure 2.3.5). Two additional lake trout spawning shoal rehabilitation sites remain. The southwestern shore of the Bobs and Crow Lake Channel and Gull shoal (Figure 2.3.5) should be enhanced through the placement of well washed rounded limestone cobble, 5-30cm in diameter near existing suitable lake trout spawning habitat.
Crow Lake Walleye Spawning Shoal Rehabilitation
Many walleye spawning areas have been already enhanced in Crow Lake. Two critical walleye spawning areas require further enhancement. The southwestern shore of the Bobs/Crow Lake channel when enhanced for lake trout will double as a walleye spawning shoal. A walleye spawning bed located below Scott’s Creek falls (Figure 2.3.5) has been severely degraded through erosion of sediment upstream of the walleye spawning area. This sediment must be removed, the substrate washed clean and replaced onto the bed of the creek. This enhancement will rehabilitate Scott’s Creek as a prime walleye spawning area for Crow Lake. Work was completed in 2002 to address the upstream sediment runoff.
3. Crow Lake Livestock Restriction There is cattle access presently at the south-eastern area of Patterson’s Bay. Cattle should be fenced out from accessing the water in these locations to prevent water quality degradation and alternative-watering sources such as nose pumps should be explored.