EGBSC has received several requests for fish assessments along eastern Georgian Bay and inland lakes and carried out at least one fish assessment survey annually. This information was coordinated with the MNRF Upper Great Lakes Management Unit (UGLMU) to help with their fish community monitoring.
In 2006, the Bayfield-Nares Islanders’ Association asked EGBSC to complete a fish population assessment survey in their area of eastern Georgian Bay. EGBSC carried out the survey in September 2007, using a Nearshore Community Index Netting survey. This type of survey helps to gather information on the abundance of fish species that inhabit waters close to the shoreline (littoral zone). EGBSC set 30 overnight trapnet sets and caught a total of 393 fish. Eleven different fish species were caught: Brown Bullhead (90), Smallmouth Bass (76), Pumpkinseed (63), Yellow Perch (40), Rock Bass (27), Largemouth Bass (24), Walleye (21), White Sucker (20), Northern Pike (17), Redhorse Sucker (11) and Bowfin (4).
EGBSC found that overall fish productivity was low and overall, the fish productivity in that area was below the Georgian Bay average. The survey was conducted in early fall, and the survey time may have been a factor in lower catch rates. Due to the size of the gear, smaller species, such as minnows, are not captured. Species that EGBSC did not capture, but expected to, include Muskellunge, Longnose Gar and Black Crappie. EGBSC would like to thank Bayfield-Nares Islanders’ Association, volunteers who assisted with netting, Mike Penrod, Garry Scale, Mike Carson and MNR.
12 Mile Bay ESTN, 2008
In 2008, EGBSC carried out a fish assessment in 12 Mile Bay using the End of Spring Trap Netting survey between May 28th and June 5th. EGBSC set 30 overnight trapnet sets and caught a total of 880 fish. Sixteen fish species were caught: Rock Bass (517), Smallmouth Bass (126), Brown Bullhead (85), Black Crappie (69), Northern Pike (31), Muskellunge (10), Largemouth Bass (10), Pumpkinseed (10), Bowfin (8), Yellow Perch (3), White Bass (3), White Sucker (2), Gar (2), Burbot (2), Lake Trout (1) and Walleye (1). By far, Rock Bass was the most abundant. For game fish, there was good size dispersion, suggesting that recruitment and mortality were balanced and that populations were stable. Muskellunge spawn in the late spring, from the size, number and location of capture, it was likely they were spawning along portions of the 12 Mile Bay shoreline during the survey. Overall, it was concluded that game fish species in 12 Mile Bay had an average abundance and were healthy and stable. Fish habitat and water clarity along the 12 Mile Bay Shoreline was extremely varied, and fish productivity also varied along the shore. EGBSC expected to capture more Walleye in that location, but only one was caught.
Lake Sturgeon Spawning Population Assessment, Moon River 2009 and 2010
Lake Sturgeon (Acipenser fluvescens) has been listed as ‘Threatened’ in Ontario and under COSEWIC (Committee on the Status of Endangered Wildlife in Canada). There has been considerable interest in Lake Sturgeon from both government agencies and the general public, in relation to conserving ecosystem biodiversity and also in maintaining a viable population. Within Georgian Bay waters and adjoining tributaries, occasional sightings of Lake Sturgeon continue to be reported to the MNRF. Most sightings occur during spawning, when Lake Sturgeon are congregated. They are very rarely reported as incidental catches or as dead fish observed along the shoreline.
EGBSC carried out visual observations of Lake Sturgeon during spawning, to see if it would be a useful tool in assessing the spawning population abundance. Visual observations were carried out at the Moon River Falls, immediately downstream during the spring of 2009 and 2010. Observations were carried out by volunteers, including white-water kayakers, the Moon River Cottage owner and Moon River guest cottagers. In total, 16 Lake Sturgeon were observed between April 25th and May 26th in 2009. In 2010, volunteers expanded the search area by 1.25km downstream. In 2010, water flow was much lower, and visual observations were only carried out on two occasions. Two Lake Sturgeon were observed and estimated at approximately four feet in length. Hundreds of Gar were observed spawning on the Moon River during that time. Although fewer visual observations were carried out in 2010, the population of spawning Lake Sturgeon may be higher than previously thought, and visual observations was a valuable method to collect information.
Killbear Channel and Parry Sound Lake Trout Egg Collection Project, 2008 and 2010
In the Great Lakes, a lack of thiamine (vitamin B1) has been linked to the failure of newly hatched Lake Trout to survive. It is believed that this is being caused by thiaminase, an enzyme that destroys thiamine, which is found in Smelt and Alewife. In order to better understand the issue, MNRF’s Upper Great Lakes Management Unit asked EGBSC to assist with collecting samples of Lake Trout eggs from Davy Island and Horse Island. While collecting egg samples, EGBSC was also able to collect spawning population data. In 2008, EGBSC set nets at two sites, over four nights. A total of 111 Lake Trout were captured, and egg samples were collected from 17 females. Sea Lamprey scarring was observed on 51 of the captured Lake Trout, and two of those had open lamprey wounds. Five of the Lake Trout had fish lice present. In 2010, nets were set at two sites for ten nights. A total of 84 Lake Trout were captured, and egg samples were collected from 12 females. Between 2008 and 2010, the size of male Lake Trout shifted towards substantially smaller fish, which can be attributed to a large influx of males from a previous spawning period. There was a slight increase in the number of Sea Lamprey wounds, but scarring rate was considerably lower. With a higher number of young male Lake Trout, they would have had less exposure to lamprey predation and scarring.
End of Spring Trap Netting was carried out in the Wah-Wah-Taysee area of eastern Georgian Bay to try and assess impacts from Round Goby on native, nearshore fish populations, create a baseline assessment for the area and complement the 2008 survey completed on 12 Mile Bay in 2008. Another goal was to help evaluate the presence of Walleye, for future consideration of re-introducing Walleye into Tadenac Bay. In total, 1,978 fish were captured. Species diversity was low, and the catch was dominated by Rock Bass and Smallmouth Bass. Twelve species were caught: Rock Bass (1,451), Smallmouth Bass (432), Northern Pike (43), Largemouth Bass (22), Walleye (8), Gar (5), Carp (5), Bullhead (4), Bowfin (4), Redhorse Sucker (2), Yellow Perch (1) and Black Crappie (1). There was excellent size distribution for Smallmouth Bass, meaning that several year classes had successfully survived. There was also a good representation of adult fish, suggesting that mortality rates were moderate. The size distribution of Northern Pike also appeared healthy. The Way-Way-Taysee area has been exposed to Round Goby for several years. The abundance of Smallmouth Bass and Rock Bass indicated there were no negative impacts that could be observed yet.