2013 Upper Rideau Lake Walleye FWIN Report Final

2013 Upper Rideau Lake Modified Fall Walleye Index Netting (FWIN) Report

August 2015

Ontario Ministry of Natural Resources and Forestry (OMNRF) Kemptville District

Cette publication hautement spécialisée {2013 Upper Rideau Lake Modified Fall Walleye Index Netting (FWIN) Report} n'est disponible qu'en anglais conformément au Règlement 671/92, selon lequel il n’est pas obligatoire de la traduire en vertu de la Loi sur les services en français. Pour obtenir des renseignements en français, veuillez communiquer avec le ministère des Richesses naturelles et des Forêts au {613-258-8214 ou joff.cote@ontario.ca}.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 2

TABLE OF CONTENTS

Executive Summary 4

List of Figures 8 List of Tables 9

1.0 INTRODUCTION 10

2.0 METHODOLOGY 12

2.1 Sampling Methods 12

2.2 Sample Size 13

2.3 Gear Description 13

2.4 Biological Sampling 13

3.0 RESULTS & DISCUSSION 14

3.1 Total Catch - Fish Community 14

3.2 Walleye 16

3.3 Yellow Perch 24

3.4 Northern Pike 32

3.5 Other Fish Species 40

4.0 CONCLUSION & RECOMMENDATIONS 59

4.1 Conclusion 59

4.2 Recommendations 62

REFERENCES 63

APPENDIX A - Set and Lift Data for 2013 Upper Rideau Lake 64

Report Author: Joffre Cote Field Assessment Team: Eric Robertson, Joffre Cote, Shaun Thompson, Allen Bibby, Megan Reaney, Mary Dillon

Cover Photo: Upper Rideau Lake Walleye Sampling, Rideau Lakes Twp, Leeds County (Photo Credit: Eric Robertson, MNRF)

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EXECUTIVE SUMMARY

Upper Rideau Lake is a shallow meso-eutrophic lake that supports a diversity of mainly warm water and cool water fish communities. The lake is currently managed primarily for Walleye, a fish species which is not native to Upper Rideau Lake.

The objective of this study was twofold: to assess the status of the lake’s Walleye, Yellow Perch and Northern Pike populations using the standardized Fall Walleye Index Netting (FWIN) methodology (Morgan, 2002); and to determine Walleye recruitment rates, which had been presumed as being low based on the lack of smaller-sized mature fish showing up at the main spawning sites in Westport, over the last several years (Westport and Area Outdoor Association Spawning Observation/Collection Reports).

The Walleye population had previously collapsed in the 1980’s and was believed to have been associated with (Burns, 2003):

 Nutrient enrichment from poor quality septic systems (causing excessive eutrophication) which led to increased abundance of aquatic vegetation and declining levels of dissolved oxygen;

 Predation and competition by other fish species; and

 Deterioration of spawning sites with consequent Walleye reproduction failure.

The 2013 Upper Rideau Lake Fall Walleye Index Netting assessment was carried out between October 21 and 25. A grand total of 916 fish were captured from a total of seventeen (17) different fish species, using eleven (11) net sets. The assessment was stopped short of the recommended number of net sites (n=18) due to a combination of vessel mechanical failure and the composition of the Walleye capture (i.e. assessment objectives had already been met).

Walleye are not native to Upper Rideau Lake. They have been stocked as eggs, summer fingerlings and fall fingerlings, from 1936 to 2001. Only large mature fish (with at least 62% of the catch originating from the last stocking efforts (2000-2001) are making up the bulk of the population structure, which can be interpreted as a sign of a heavily stressed fishery. The top 5 species (Pumpkinseed, Rock Bass, Yellow Perch, Smallmouth Bass and Bluegill) captured during the 2013 assessment, for a combined total of 82% of the catch, are all competitor/predator species of Walleye, for the latter’s various early life stages.

The mean size and age of Walleye was significantly higher than zone averages. Even though the current catch rate of 1.9 fish per net would categorize the lake’s Walleye Population to be of low to moderate abundance level, in comparison to the Fisheries Management Zone (FMZ) 18 mean catch rate of 3 fish per net, with evidence of extremely poor recruitment, of the mean

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age of the fish captured during the assessment and of the mean age showing up at the main spawning sites in recent springs (Westport and Area Outdoor Association Spawning Observation/Collection Reports), very low fish abundance levels (i.e. remnant population) can be forecasted in the near future.

The mean catch rate, size, age and growth rates of Yellow Perch and Northern Pike were higher than FMZ 18 averages. The lake’s Yellow Perch population is very healthy and is not showing any signs of heavy mortality, and the lake’s Northern Pike population is relatively healthy.

It would appear that this lake likely has a tremendous warm water fishery, for the following species: Smallmouth Bass, Pumpkinseed, Bluegill, Rock Bass, and potentially to some extent, Largemouth Bass.

The major contributing factor to the recent (and potentially the previous) collapse of the lake’s Walleye population is indeed predation and competition by other fish species. This latter factor likely has, and left unchecked will continue to have incremental impacts to the Walleye population, due to climate change favouring warm water fish communities.

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RÉSUMÉ

Le lac Upper Rideau est un lac méso-eutrophe peu profond où vivent diverses communautés de poissons principalement d’eaux chaudes et tempérées. Il est actuellement géré pour le doré jaune, une espèce de poisson qui n’est pas indigène au lac Upper Rideau.

L’objectif de cette étude était double : déterminer l’état des populations de doré jaune, de perchaude et de grand brochet du lac au moyen du Décompte automnal de prises de dorés au filet (DAPDF) (Morgan, 2002), et de déterminer les taux de recrutement de doré jaune, qu’on présumait bas en raison de l’absence de poissons adultes de plus petite taille dans les principales frayères de Westport au cours des dernières années (Westport and Area Outdoor Association Spawning Observation/Collection Reports).

La population de dorés jaunes avait chuté pendant les années 1980, et l’on croyait que cela était lié à (Burns, 2003) :

 L’enrichissement en nutriments provenant d’installations septiques de qualité médiocre (causant une eutrophisation excessive), qui a conduit à une augmentation de la végétation aquatique et à des niveaux plus bas d’oxygène dissous;

 La prédation et la concurrence d’autres espèces de poissons;

 La détérioration de frayères et l’échec consécutif de la reproduction du doré jaune.

Le Décompte automnal de prises de dorés au filet en 2013 dans le lac Upper Rideau a été effectué entre le 21 et le 25 octobre. En tout, 916 poissons ont été capturés, de dix-sept (17) espèces différentes, à l’aide de onze (11) ensembles de filets. On a mis fin à l’évaluation sans avoir atteint le nombre recommandé d’emplacements de filets (18) en raison d’une combinaison de pannes mécaniques de bateaux et de la composition des prises de dorés jaunes (c’est-à-dire que les objectifs de l’évaluation avaient déjà été atteints).

Le doré jaune n’est pas indigène au lac Upper Rideau. Il a fait l’objet d’empoissonnement sous la forme d’œufs, d’alevins de l’été et d’alevins de l’automne, de 1936 à 2001. Seuls de grands poissons adultes [au moins 62 % des prises remontant aux dernières activités d’empoissonnement (2000-2001)] constituent le gros de la structure démographique, ce que l’on peut interpréter comme un signe d’une pêche subissant un stress considérable. Les 5 espèces (crapet-soleil, crapet de roche, perchaude, achigan à petite bouche et crapet arlequin) le plus capturées au cours de l’évaluation de 2013, soit 82 % du total, sont toutes des espèces concurrentes et prédatrices du doré jaune, lors des premières étapes de son cycle de vie.

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La taille et l’âge moyens des dorés jaunes étaient notablement plus élevés que dans l’ensemble de la zone. Même si le taux de prise actuel de 1,9 poisson par filet semble indiquer que la population de dorés jaunes du lac est de faiblement à modérément abondante si on compare ce taux au taux de prise moyen de la Zone de gestion des pêches (ZGP) 18, qui est de 3 poissons par filet, compte tenu d’un recrutement extrêmement médiocre, de l’âge moyen des poissons capturés au cours de l’évaluation et de l’âge moyen observé dans les principales frayères ces derniers printemps (Westport and Area Outdoor Association Spawning Observation/Collection Reports), on peut prévoir dans un proche avenir des niveaux d’abondance très bas (c’est-à-dire une population relique) pour les poissons.

Le taux de prise moyen, la taille, l’âge et les taux de croissance de la perchaude et du grand brochet étaient plus élevés que les moyennes observées dans la ZGP 18. La population de perchaudes du lac est très saine et ne donne pas de signes d’une forte mortalité, et la population de grands brochets du lac est relativement saine.

Il semblerait qu’on trouve dans ce lac de remarquables pêches d’eaux chaudes pour les espèces suivantes : achigan à petite bouche, crapet-soleil, crapet arlequin, crapet de roche et, potentiellement dans une certaine mesure, achigan à grande bouche.

Le principal facteur expliquant l’effondrement récent (et peut-être l’effondrement précédent) de la population de dorés jaunes du lac est bel et bien la prédation et la concurrence d’autres espèces de poissons. Ce dernier facteur a vraisemblablement, et continuera d’avoir si rien n’est fait, des impacts différentiels sur la population de dorés jaunes, en raison du changement climatique, qui favorise les communautés de poissons d’eaux chaudes.

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List of Figures

Fig. 1. Fish species composition 15 Fig. 2. Walleye total length distribution 17 Fig. 3. Walleye age distribution 19 Fig. 4. Male Walleye length at age 20 Fig. 5. Female Walleye length at age 21 Fig. 6. Male Walleye length to weight relationship 22 Fig. 7. Female Walleye length to weight relationship 23 Fig. 8. Yellow Perch fork length distribution 25 Fig. 9. Yellow Perch age distribution 27 Fig. 10. Male Yellow Perch length at age 28 Fig. 11. Female Yellow Perch length at age 29 Fig. 12. Male Yellow Perch length to weight relationship 30 Fig. 13. Female Yellow Perch length to weight relationship 31 Fig. 14. Northern Pike total length distribution 33 Fig. 15. Northern Pike age distribution 35 Fig. 16. Male Northern Pike length at age 36 Fig. 17. Female Northern Pike length at age 37 Fig. 18. Male Northern Pike length to weight relationship 38 Fig. 19. Female Northern Pike length to weight relationship 39 Fig. 20. Smallmouth Bass fork length distribution 40 Fig. 21. Smallmouth Bass age distribution 41 Fig. 22. Smallmouth Bass length at age 42 Fig. 23. Smallmouth Bass length to weight relationship 42 Fig. 24. Largemouth Bass fork length distribution 43 Fig. 25. Largemouth Bass age distribution 44 Fig. 26. Largemouth Bass length at age 45 Fig. 27. Largemouth Bass length to weight relationship 45 Fig. 28. Pumpkinseed fork length distribution 46 Fig. 29. Pumpkinseed age distribution 47 Fig. 30. Pumpkinseed length at age 48 Fig. 31. Pumpkinseed length to weight relationship 48 Fig. 32. Bluegill fork length distribution 49 Fig. 33. Bluegill age distribution 50 Fig. 34. Bluegill length at age 51 Fig. 35. Bluegill length to weight relationship 51 Fig. 36. Rock Bass fork length distribution 52 Fig. 37. Rock Bass age distribution 53 Fig. 38. Rock Bass length at age 54 Fig. 39. Rock Bass length to weight relationship 54 Fig. 40. Brown Bullhead total length distribution 55 Fig. 41. Brown Bullhead length to weight relationship 56

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List of Tables

Table 1. Summary of protocol for FWIN 12

Table 2. Fish species captured 14

Table 3. Netting precision (Relative Standard Error) for sport fish species captured 15

Table 4. Walleye Total Length and Age Descriptive Statistics 18

Table 5. Yellow Perch Total Length and Age Descriptive Statistics 26

Table 6. Northern Pike Total Length and Age Descriptive Statistics 34

Table 7. Size ranges of other fish species captured 57

Table 8. Age ranges of other fish species captured 58

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1.0 INTRODUCTION

Upper Rideau Lake is situated at the mid-point (and headwaters) of the Rideau Canal system, which flows towards both Ottawa and Kingston, within the County of Leeds and Grenville. It is the 13th largest lake within Ontario’s Fisheries Management Zone (FMZ) 18. The town of Westport lies on the northwest corner of the lake and relies heavily on the tourist industry as a source of income during the summer season. Originally an integral part of Big Rideau Lake, Upper Rideau Lake was created during construction of the Rideau Canal between 1826 and 1832 when the Narrows was damned to raise the upstream water level. The Canal connected Upper Rideau Lake with Big Rideau Lake to the east and Newboro Lake to the south, so that the lake had two outlets.

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The northern (and mostly natural) part of the lake lies in the Canadian Shield and is dominated by a 70 m escarpment of Precambrian granite and the Rideau Fault. The southern shore is situated on the edge of the Great Lakes – St. Lawrence lowland, which has shallow mantle overlaying bedrock of limestone, dolomite, sandstone and shale. The southern shoreline was cleared for farming during the 1700’s and 1800’s (Lee, 1995). Currently, permanent and seasonal residences occupy the southern shoreline.

Upper Rideau Lake is a shallow meso-eutrophic lake that supports a diversity of mainly warm water and cool water fish communities.

Walleye are not native to Upper Rideau Lake. They were stocked as eggs from 1936 to 1972, as summer fingerlings in 1988 and 1989 (175,000/year), and as larger fall fingerlings in 1994 and 1995 (40,000/year), and again in 2000 and 2001 (33,000/year) to reduce predation by other fish species. The Ontario Ministry of Natural Resources (OMNR) conducted fisheries assessments in 1982, 1984, 1986, 1988, 1990, 1993, 1994, 1998, 1999, 2000, 2001, 2002 and 2005.

During the 1980’s, the Walleye population in Upper Rideau Lake collapsed. Surveys conducted by OMNR from the 1960’s to the 1980’s have documented this decline. The collapse of the Walleye population was believed to have been associated with:

 Nutrient enrichment from poor quality septic systems (causing excessive eutrophication) which led to increased abundance of aquatic vegetation and declining levels of dissolved oxygen;

 Predation and competition by other fish species; and

 Deterioration of spawning sites with consequent Walleye reproduction failure.

Many partners assisted OMNR’s efforts towards trying to restore the Walleye population (The Town of Westport constructed a new sewage treatment plan in the late 1990’s; The Westport and Area Outdoor Association rehabilitated spawning sites), however as the Walleye population peaked in 1998-1999 as a direct result of the fall fingerling stockings, the then recent

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assessment data demonstrated that the long-term viability of a sustainable, self-reproducing population was questionable. A then recent invasion of zebra mussels was also creating additional stress for this light-sensitive fish species preferring “turbid/cloudy” waters. Zebra mussels filter out the micro-organisms in the water, making it clearer and allowing more light to penetrate deeper into the water column, therefore reducing the amount of available habitat for Walleye (Burns, 2003).

2.0 METHODOLOGY

The FWIN method (Morgan, 2002) utilizes a stratified random sampling design in which the individual sampling units are selected without replacement. The strata used in the design are area and depth. The selection of sampling sites is done randomly (mapping exercise in the office) to minimize bias in locating sites and setting the gear. Sites must not be substituted without a valid reason (e.g. water too shallow or too deep, areas with high shoreline development, impeding boat traffic, unsuitable topography, etc.).

2.1 Sampling Methods

The basic sampling methods for FWIN are summarized in Table 1. As the name implies, the field survey occurs during the fall. Sampling starts once surface water temperatures have cooled to 15ºC and may continue until surface temperature reaches 10ºC. In most parts of Ontario the sampling window begins in mid-September and extends to late October or early November (a 6-8 week sampling period).

The gillnet gang is made up of 8 panels of different size mesh, ranging from 25 mm to 152 mm. At each site, one gillnet gang is set perpendicular to shore and left to fish overnight. The duration of the set should be 24 hours, acknowledging that this is a target only and some reasonable variance is acceptable.

Table 1: Summary of protocols for FWIN Criteria Target Season  Fall when surface water temperature is between 15ºC and 10ºC Set Duration  24 hours Gear  Gillnet gang: 8 mesh sizes (25 mm to 152 mm), each mesh panel 1.8 m deep x 7.6 m long Orientation  Perpendicular to shoreline contour Depth  2 strata: 2 to 5 m and 5 to 15 m Spatial Stratification  Not required for most lakes

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2.2 Sample Size

Trends in Walleye population size are evaluated base upon catch rate or catch-per-unit-effort (CUE), which is the average number of Walleye captured per net. The number of net sets will influence the reliability of the CUE estimate derived from a FWIN survey. The minimum sample size target for any waterbody is 8 sites. However, a fixed sample size may not be applicable for comparisons across varying spatial scales, for example small versus large waterbodies. In order to improve the CUE estimate, surveyors are encouraged to increase the number of net sets beyond the minimum sample size. A more suitable design based on Upper Rideau Lake’s surface area (1363 ha) (OMNRF, 2014) is recommended as being 18 net sites (1001-2000 ha waterbody surface area), for comparisons among lakes. However, sample size requirements can also be related to specific management objectives, independent of waterbody size (Morgan, 2002).

2.3 Gear Description

The Standard FWIN gear is a 1.8 m (6 feet) deep by 61.0 m (200 feet) long monofilament gillnet consisting of 8 mesh sizes. Each mesh panel is 7.6 m (25 feet) long. The following meshes (stretched measurements) are sewn together in ascending order of size with no spacers:

 25 mm (1.0 in.)

 38 mm (1.5 in.)

 51 mm (2.0 in.)

 64 mm (2.5 in.)

 76 mm (3.0 in.)

 102 mm (4.0 in.)

 127 mm (5.0 in.)

 152 mm (6.0 in.) 2.4 Biological Sampling

All sport fish, and a sub-sample of non-traditional sport fish and coarse fish, were biologically sampled (Total Length, Fork Length, Round Weight, Scale Sample (+ Otolith or Spine for all Walleye; Cleithrum for all Northern Pike).

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3.0 RESULTS & DISCUSSION

3.1 Total Catch – Fish Community

The 2013 Upper Rideau Lake Fall Walleye Index Netting assessment was carried out between October 21 and 25. A grand total of 916 fish were captured from a total of seventeen (17) different fish species, using eleven (11) net sets, summarized in Figure 1 and Table 2. The assessment was stopped short of the recommended number of net sites (n=18) due to a combination of vessel mechanical failure and the composition of the Walleye capture (i.e. assessment objectives had already been met). However, the minimum sample size target (number of net sites required) for any waterbody of 8 sites (Morgan, 2002), was achieved.

Table 2: Fish species captured in 2013 Upper Rideau Lake Modified FWIN assessment. Fish Species Scientific Name Number captured Catch Per Unit Effort (n) (CUE) (# fish/net) Pumpkinseed Lepomis gibbosus 220 20 Rock Bass Ambloplites rupestris 214 19.5 Yellow Perch Perca flavescens 200 18.2 Smallmouth Bass Micropterus dolomieu 71 6.5 Bluegill Lepomis macrochirus 47 4.3 Brown Bullhead Ameiurus nebulosus 45 4.1 Northern Pike Esox Lucius 37 3.4 Walleye Sander vitreum 21 1.9 Largemouth Bass Micropterus salmoides 14 1.3 Alewife Alosa pseudoharengus 13 1.2 White Sucker Catostomus commersonii 11 1 Yellow Bullhead Ameiurus natalis 9 0.8 Golden Shiner Notemigonus crysoleucas 6 0.5 Black Crappie Pomoxis nigromaculatus 4 0.4 Common Carp Cyprinus carpio 2 0.2 Silver Redhorse Moxostoma anisurum 1 0.1 Burbot Lota lota 1 0.1

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Pumpkinseed (24%) Rock Bass (23%) Yellow Perch (22%) Smallmouth Bass (8%) Bluegill (5%) Brown Bullhead (5%) Northern Pike (4%) Walleye (2%) Largemouth Bass (2%) Alewife (1%) White Sucker (1%) Yellow Bullhead (1%) Golden Shiner Black Crappie Common Carp

Figure 1. Fish species composition (2013 FWIN assessment of Upper Rideau Lake (n=916)).

Upper Rideau Lake (Rideau Lakes Twp., Leeds County) has a surface area of 1363ha (3368 ac), a mean and maximum depth of 8 m (26 feet) and 21.9 m (72 feet), respectively. The species specific netting precision or Relative Standard Error (RSE) are summarized in Table 3.

Table 3: Netting Precision (Relative Standard Error) for sport fish species captured in the 2013 Upper Rideau Lake Modified FWIN assessment. Fish Species Netting Precision (RSE) % Walleye 33 Yellow Perch 34 Northern Pike 26 Smallmouth Bass 41 Largemouth Bass 46 Pumpkinseed 19 Bluegill 57

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3.2 Walleye

Abundance

The mean catch rate (CUE) for Walleye in Upper Rideau Lake was 1.9 fish per net. The mean catch rate for Walleye caught in FWIN surveys (1996-2009) in FMZ 18 was 3 fish per net (OMNRF, 2014).

Size and age

The size distribution of Walleye captured in Upper Rideau Lake is summarized in Figure 2. In the 2014 FMZ 18 Fisheries Background Report, the mean total length of Walleye captured from FWIN was 406 (s.d. 91.6) mm (male) and 415 (s.d. 127.2) mm (female), indicating that Upper Rideau Lake’s Walleye population is of much larger size class overall, at a combined mean total length of 656 (43.4) mm (Table 4).

A greater number of age classes and high maximum age are indicative of successful recruitment and adult survival. Maximum age for Walleye varies from 10-12 years in southern Canada (Scott & Crossman, 1998). The age distribution of Walleye captured in Upper Rideau Lake is summarized in Figure 3. The data shows that most fish captured had reached and surpassed the usual maximum life expectancy of age 10-12.

The Walleye population’s mean age of 12 (s.d. 1.4) years is much higher than the zone’s mean age of 4 (s.d. 3.2) years, potentially reflective of an older, quasi-remnant fish population.

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70 60 U. Rideau FWIN n=14 males 50 n=6 females 40 30

20 Male Frequency(%) 10 Female

731-760 131-160 161-190 191-220 221-250 251-280 281-310 311-340 341-370 371-400 401-430 431-460 461-490 491-520 521-550 551-580 581-610 611-640 641-670 671-700 701-730 Total Length (mm)

70 FMZ 18 FWIN 60 n=1055 males

n=652 females 50 40 30 Male

Frequency(%) 20 Female 10

521-550 131-160 161-190 191-220 221-250 251-280 281-310 311-340 341-370 371-400 401-430 431-460 461-490 491-520 551-580 581-610 611-640 641-670 671-700 701-730 731-760 Total Length (mm)

Figure 2. Walleye total length distribution (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

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Table 4: 2013 Upper Rideau Lake Modified FWIN & FMZ 18 Combined FWIN (1996-2009) Walleye Total Length and Age Descriptive Statistics.

Upper Rideau Lake: FMZ 18: Mean Total Length 655.7143 Mean Total Length 397.3036677 Standard Error 9.479839 Standard Error 2.617479414 Median 640 Median 388 Mode 623 Mode 395 Standard Deviation 43.44208 Standard Deviation 112.7036911 Sample Variance 1887.214 Sample Variance 12702.12198 Kurtosis -0.26673 Kurtosis 0.024603176 Skewness 0.868885 Skewness 0.273824415 Range 148 Range 629 Minimum 596 Minimum 126 Maximum 744 Maximum 755 Sum 13770 Sum 736601 Count 21 Count 1854 Largest(1) 744 Largest(1) 755 Smallest(1) 596 Smallest(1) 126 Confidence Level(95.0%) 19.7746 Confidence Level(95.0%) 5.133518516

Upper Rideau Lake: FMZ 18: Mean Age 12.09524 Mean Age 3.811218986 Standard Error 0.31551 Standard Error 0.074598109 Median 13 Median 3 Mode 13 Mode 2 Standard Deviation 1.445848 Standard Deviation 3.212052875 Sample Variance 2.090476 Sample Variance 10.31728367 Kurtosis 1.07641 Kurtosis 5.551469382 Skewness -1.38891 Skewness 1.932813609 Range 5 Range 26 Minimum 9 Minimum 0 Maximum 14 Maximum 26 Sum 254 Sum 7066 Count 21 Count 1854 Largest(1) 14 Largest(1) 26 Smallest(1) 9 Smallest(1) 0 Confidence Level(95.0%) 0.658142 Confidence Level(95.0%) 0.146305172

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80 70 U. Rideau FWIN n=14 males

60 n=6 females 50

40 Female

30 Male Frequency(%) 20 10 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 Age (years)

80 FMZ 18 FWIN 70 n=1055 males

60 n=650 females

50 40 Male 30

Frequency(%) Female 20 10 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 Age (years)

Figure 3. Walleye age distribution (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

Growth and Maturity

Growth rates of Walleye are dependent on habitat quality, food availability, and sex. The length at age of Walleye captured in Upper Rideau Lake, summarized in Figures 4 and 5, are somewhat higher than the zone averages.

Sexual maturity (50%) is achieved by age 3 (males) and 5 (females) in FMZ 18 (OMNRF, 2014). All of the Walleye captured during the 2013 Upper Rideau Lake assessment were sexually mature.

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800

700

600

500

400 U. Rideau FWIN 300 Male Total Length (mm) 200 n=14

100

0 0 5 10 15 20 25 30 Age (years) 800

700 R² = 0.7708

600

500

400

300

FMZ 18 FWIN TotalLength (mm) 200 Male n=1035 100

0 0 5 10 15 20 25 30 Age (years) Figure 4. Male Walleye length at age (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

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800

700

600

500

400

300 U. Rideau FWIN Female Total Length (mm) 200 n=6

100

0 0 5 10 15 20 25 30 Age (years)

800

700 R² = 0.8012

600

500

400

300

FMZ 18 FWIN TotalLength (mm) 200 Female n=622 100

0 0 5 10 15 20 25 30 Age (years) Figure 5. Female Walleye length at age (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

The annual mortality rate of Upper Rideau Lake’s Walleye population could not be determined due to the fish samples’ size and age distributions.

The condition of Walleye sampled in the 2013 Upper Rideau Lake assessment is summarized as a reference point in time, in Figures 6 and 7, which shows the relationship between total length and round weight.

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6000

5000 R² = 0.6548

4000

3000

2000 U. Rideau FWIN

Round Weight (g) Male 1000 n=14

0 0 100 200 300 400 500 600 700 800 Total Length (mm)

6000

R² = 0.9807

5000

4000

3000

2000 FMZ 18 FWIN Round Weight (g) Male 1000 n=1055

0 0 100 200 300 400 500 600 700 800 Total Length (mm)

Figure 6. Male Walleye length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

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6000

5000 R² = 0.7473

4000

3000

2000 U. Rideau FWIN Round Weight (g) Female 1000 n=6

0 0 100 200 300 400 500 600 700 800 Total Length (mm)

6000

R² = 0.985

5000

4000

3000

2000 FMZ 18 FWIN Round Weight (g) Female 1000 n=652

0 0 100 200 300 400 500 600 700 800 Total Length (mm)

Figure 7. Female Walleye length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

In summary, Upper Rideau Lake’s Walleye population is currently considered to be of very high quality (in terms of mean fish size with a Fishing Quality Index (FQI)** value of 324 – FMZ 18 FQI value of 128), with relatively abundant opportunities to catch ‘Quality’ and ‘Memorable’ class fish. Unfortunately, with extremely poor recruitment and the mean age of the fish captured during the assessment, very low fish abundance can be forecasted in the near future, even though the current catch rate of 1.9 fish/net (FMZ 18 mean catch rate of 3 fish/net) would indicate a low to moderate abundance level.

**The quality of the various FMZ 18 Sport Fisheries Resources was determined by using a Fishing Quality Index, which provides a measure of the size distribution within a fish population (OMNRF, 2014).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 23

3.3 Yellow Perch

Abundance

The mean catch rate (CUE) for Yellow Perch in Upper Rideau Lake was 18.2 fish per net. The mean catch rate for Yellow Perch caught in FWIN surveys (1996-2009) in FMZ 18 was 4.8 fish per net (OMNRF, 2014).

Size and Age

The size distribution of Yellow Perch captured in Upper Rideau Lake is summarized in Figure 8. In the 2014 FMZ 18 Fisheries Background Report, the mean fork length of Yellow Perch captured from FWIN was 149 (s.d. 44.8) mm, indicating that Upper Rideau Lake’s Yellow Perch population is of much larger size class overall, at a mean fork length of 203 (s.d. 46.9) mm (Table 5).

A greater number of age classes and high maximum age are indicative of successful recruitment and adult survival. Maximum age for Yellow Perch varies from 9-10 years in southern Canada (Scott & Crossman 1998). The age distribution of Yellow Perch captured in Upper Rideau Lake is summarized in Figure 9. The data shows that many fish captured were close to reaching the usual maximum life expectancy of age 9-10.

The Yellow Perch population’s mean age of 4 (1.7) years is higher than the zone’s mean age of 3 (s.d. 1.5) years, which is indicative of a healthy population.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 24

70 60 U. Rideau FWIN n=30 males

50 n=39 females 40 30 Male

Frequency(%) 20 Female 10 0

Fork Length (mm)

70 FMZ 18 FWIN 60 n=356 males 50 n=575 females 40

30 Male

Frequency(%) 20 Female 10 0

Fork Length (mm)

Figure 8. Yellow Perch fork length distribution (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 25

Table 5: 2013 Upper Rideau Lake Modified FWIN & FMZ 18 Combined FWIN (1996-2009) Yellow Perch Fork Length and Age Descriptive Statistics. Upper Rideau Lake: FMZ 18: Mean Fork Length 203.1392 Mean Fork Length 149.2337058 Standard Error 5.279028 Standard Error 0.966949587 Median 197 Median 146 Mode 191 Mode 104 Standard Deviation 46.92103 Standard Deviation 44.81474926 Sample Variance 2201.583 Sample Variance 2008.361751 Kurtosis -0.4064 Kurtosis 0.80906009 Skewness 0.152174 Skewness 0.997167171 Range 196 Range 251 Minimum 94 Minimum 83 Maximum 290 Maximum 334 Sum 16048 Sum 320554 Count 79 Count 2148 Largest(1) 290 Largest(1) 334 Smallest(1) 94 Smallest(1) 83 Confidence Confidence Level(95.0%) 10.50974 Level(95.0%) 1.896255364

Upper Rideau Lake: FMZ 18: Mean Age 4.407895 Mean Age 2.529411765 Standard Error 0.19119 Standard Error 0.054162977 Median 4 Median 2 Mode 4 Mode 2 Standard Deviation 1.666754 Standard Deviation 1.49807391 Sample Variance 2.77807 Sample Variance 2.244225439 Kurtosis -0.96882 Kurtosis 4.881365097 Skewness -0.10977 Skewness 1.573197212 Range 6 Range 12 Minimum 1 Minimum 0 Maximum 7 Maximum 12 Sum 335 Sum 1935 Count 76 Count 765 Largest(1) 7 Largest(1) 12 Smallest(1) 1 Smallest(1) 0 Confidence Confidence Level(95.0%) 0.38087 Level(95.0%) 0.106325925

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 26

40 U. Rideau FWIN 35 n=28 males n=38 females

25 Male 20 Female

15 Frequency(%) 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 Age (years)

40 FMZ 18 FWIN 35 n=288 males

30 n=473 females

20 Male

15 Female Frequency(%) 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 13 Age (years)

Figure 9. Yellow Perch age distribution (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

Growth and Maturity

Growth rates of Yellow Perch are dependent on habitat quality, food availability, and sex. The length at age of Yellow Perch captured in Upper Rideau Lake, summarized in Figure 10 and 11, are significantly higher than the zone averages.

Sexual maturity is usually achieved by age 3 (males) and 4 (females) (Scott & Crossman, 1998). Comparing the length at age 3-4 years (Figure 10 and 11) and the above fork length distributions (Figure 8) would indicate that in Upper Rideau Lake, there is a very strong component of sexually mature fish, as well as good total age class representation, suggesting successful spawning and population recruitment.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 27

350

300

250 R² = 0.7148

200

150 U. Rideau

Fork LengthFork (mm) 100 FWIN Male 50 n=28

0 0 2 4 6 8 10 12 14 Age (years) 350

300 R² = 0.3637

250

200

150 FMZ 18 FWIN Fork LengthFork (mm) 100 Male n=286 50

0 0 2 4 6 8 10 12 14 Age (years) Figure 10. Male Yellow Perch length at age (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 28

350

300 R² = 0.496

250

200

150 U. Rideau Fork LengthFork (mm) 100 FWIN Female 50 n=38

0 0 2 4 6 8 10 12 14 Age (years)

350

300

R² = 0.5141 250

200

150 FMZ 18 Fork LengthFork (mm) 100 FWIN 50 Female n=473 0 0 2 4 6 8 10 12 14 Age (years)

Figure 11. Female Yellow Perch length at age (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

Population dynamics are also influenced by annual mortality rates. The annual mortality rate of Upper Rideau Lake’s Yellow Perch male population is 46% (calculated using a Catch Curve Analysis (i.e. descending slope of the Ln frequency distribution of the age class)), which is similar to the zone’s average of 51%. The rate could not be determined for females due to the fish samples’ age distribution. The combined (male and female) annual mortality rate is 45%.

The condition of Yellow Perch sampled in the 2013 Upper Rideau Lake assessment is summarized as a reference point in time, in Figures 12 and 13, which shows the relationship between fork length and round weight.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 29

350

300 R² = 0.8876

250

200

150 U. Rideau Round Weight (g) 100 FWIN Male 50 n=30 0 0 50 100 150 200 250 300 Fork Length (mm) 350

300 R² = 0.9547

250

200

150 FMZ 18 Round Weight (g) 100 FWIN Male 50 n=325 0 0 50 100 150 200 250 300 Fork Length (mm)

Figure 12. Male Yellow Perch length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 30

500 450 400

R² = 0.9244 350 300 250 200 U. Rideau FWIN Round Weight (g) 150 Female 100 n=39 50 0 0 50 100 150 200 250 300 350 Fork Length (mm)

500 450 400 R² = 0.9739

350 300 250 200 FMZ 18

Round Weight (g) 150 FWIN Female 100 n=523 50 0 0 50 100 150 200 250 300 350 Fork Length (mm) Figure 13. Female Yellow Perch length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

In summary, Upper Rideau Lake’s Yellow Perch population is currently considered to be of very high quality (in terms of mean fish size with a Fishing Quality Index (FQI)** value of 213 – FMZ 18 FQI value of 96), with relatively abundant opportunities to catch ‘Quality’ and ‘Memorable’ class fish. The population has excellent recruitment, and high fish abundance (catch rate (CUE) of 18.2 fish per net, in comparison to the zone’s mean CUE of 4.8 fish per net).

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3.4 Northern Pike

Abundance

The mean catch rate (CUE) for Northern Pike in Upper Rideau Lake was 3.4 fish per net. The mean catch rate for Northern Pike caught in FWIN surveys (1996-2009) in FMZ 18 was 1.4 fish per net (OMNRF, 2014).

Size and Age

The size distribution of Northern Pike captured in Upper Rideau Lake is summarized in Figure 14. In the 2014 FMZ 18 Fisheries Background Report, the mean total length of Northern Pike captured from FWIN was 561 (s.d. 127.1) mm, indicating that Upper Rideau Lake’s Northern Pike population is of larger size class overall, at a mean total length of 615 (s.d. 108.7) mm (Table 6).

A greater number of age classes and high maximum age are indicative of successful recruitment and adult survival. Maximum age for Northern Pike varies from 10-12 years in southern Canada (Scott & Crossman 1998). The age distribution of Northern Pike captured in Upper Rideau Lake is summarized in Figure 15. The data shows that none of the fish captured were close to reaching the usual maximum life expectancy of age 10-12.

The Northern Pike population’s mean age of 4 (s.d. 1.4) years is higher than the zone’s mean age of 3 (s.d. 1.9) years, which is potentially indicative of a somewhat healthier population.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 32

40 35 U. Rideau FWIN n=10 males 30 n=24 females 25 20 Male 15

Frequency(%) 10 Female 5

51-100

601-650 101-150 151-200 201-250 251-300 301-350 351-400 401-450 451-500 501-550 551-600 651-700 701-750 751-800 801-850 851-900 901-950 951-1000

Total Length (mm) 1001-1050

40 FMZ 18 FWIN 35 n=263 males

30 n=416 females 25 20 15 Male Frequency(%) 10 Female 5

51-100

801-850 101-150 151-200 201-250 251-300 301-350 351-400 401-450 451-500 501-550 551-600 601-650 651-700 701-750 751-800 851-900 901-950

951-1000 1001-1050 Total Length (mm)

Figure 14. Northern Pike total length distribution (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

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Table 6: 2013 Upper Rideau Lake Modified FWIN & FMZ 18 Combined FWIN (1996-2009) Northern Pike Total Length and Age Descriptive Statistics.

Upper Rideau Lake: FMZ 18: Mean Total Length 614.8649 Mean Total Length 561.119215 Standard Error 17.86495 Standard Error 4.76027401 Median 595 Median 538 Mode 488 Mode 484 Standard Deviation 108.6682 Standard Deviation 127.109121 Sample Variance 11808.79 Sample Variance 16156.7287 Kurtosis -0.25902 Kurtosis 1.33965839 Skewness 0.663042 Skewness 0.9464453 Range 404 Range 787 Minimum 476 Minimum 254 Maximum 880 Maximum 1041 Sum 22750 Sum 400078 Count 37 Count 713 Largest(1) 880 Largest(1) 1041 Smallest(1) 476 Smallest(1) 254 Confidence Confidence Level(95.0%) 9.34585263 Level(95.0%) 36.2318

Upper Rideau Lake: FMZ 18: Mean Age 3.621622 Mean Age 3.028449502 Standard Error 0.236819 Standard Error 0.073491566 Median 3 Median 3 Mode 2 Mode 2 Standard Deviation 1.440512 Standard Deviation 1.948566209 Sample Variance 2.075075 Sample Variance 3.796910271 Kurtosis -0.11739 Kurtosis 3.444809307 Skewness 0.715194 Skewness 1.634003678 Range 5 Range 13 Minimum 2 Minimum 0 Maximum 7 Maximum 13 Sum 134 Sum 2129 Count 37 Count 703 Largest(1) 7 Largest(1) 13 Smallest(1) 2 Smallest(1) 0 Confidence Confidence Level(95.0%) 0.144289595 Level(95.0%) 0.480291

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50 U. Rideau FWIN n=10 males 40

n=24 females

30 Male

20 Female Frequency(%) 10

0 1 2 3 4 5 6 7 8 9 10 11 12 13 Age (years)

50 FMZ 18 FWIN n=260 males

40 n=411 females

30 Male 20

Female Frequency(%)

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Age (years)

Figure 15. Northern Pike age distribution (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

Growth and Maturity

Growth rates of Northern Pike are dependent on habitat quality, food availability, and sex. The length at age of Northern Pike captured in Upper Rideau Lake, summarized in Figure 16 and 17 are similar to the zone averages.

Sexual maturity (50%) is achieved by age 2 (male and female) in FMZ 18 (OMNRF, 2014). Comparing the length at age 2 years (Figure 16 and 17) and the above fork length distributions (Figure 14) would indicate that in Upper Rideau Lake, there is a very strong component of sexually mature fish, as well as good total age class representation, suggesting successful spawning and population recruitment.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 35

1200

1000 R² = 0.698

800

600

400 U. Rideau

TotalLength (mm) FWIN 200 Male n= 10 0 0 2 4 6 8 10 12 14 Age (years) 1200

R² = 0.5823

1000

800

600

400 FMZ 18 TotalLength (mm) FWIN 200 Male n=259 0 0 2 4 6 8 10 12 14 Age (years)

Figure 16. Male Northern Pike length at age (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 36

1200

1000 R² = 0.8931

800

600

Frequency(%) 400 U. Rideau FWIN 200 Female n= 24 0 0 2 4 6 8 10 12 14 Age (years) 1200

1000 R² = 0.6959

800

600

400 FMZ 18

TotalLength (mm) FWIN Female 200 n=409

0 0 2 4 6 8 10 12 14 Age (years) Figure 17. Female Northern Pike length at age (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

Population dynamics are also influenced by annual mortality rates. The annual mortality rate of Upper Rideau Lake’s Northern Pike population is 59% (males) and 39% (females) (calculated using a Catch Curve Analysis (i.e. descending slope of the Ln frequency distribution of the age class)), which is significantly higher than the zone’s averages of 43% and 33%, respectively, although the male mortality rate is skewed due to the limited number of age classes (n=2).

The condition of Northern Pike sampled in the 2013 Upper Rideau Lake assessment is summarized as a reference point in time, in Figures 18 and 19, which shows the relationship between fork length and round weight.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 37

9000 8000 R² = 0.513

7000 6000 5000 4000 3000 Round Weight (g) 2000 U. Rideau FWIN 1000 Male 0 n= 10 0 200 400 600 800 1000 1200 Total Length (mm) 9000 8000

7000 R² = 0.9365

6000 5000 4000 3000 FMZ 18 Round Weight (g) FWIN 2000 Male 1000 n=262 0 0 200 400 600 800 1000 1200 Total Length (mm)

Figure 18. Male Northern Pike length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 38

9000 8000 R² = 0.9764

7000 6000 5000 4000 3000 U. Rideau Round Weight (g) 2000 FWIN Female 1000 n=24 0 0 200 400 600 800 1000 1200 Total Length (mm)

9000 8000 R² = 0.9621

7000

6000 5000 4000 FMZ 18 3000

Round Weight (g) FWIN 2000 Female n=414 1000 0 0 200 400 600 800 1000 1200 Total Length (mm)

Figure 19. Female Northern Pike length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment & FMZ 18 combined FWIN assessments (1996-2009)).

In summary, Upper Rideau Lake’s Northern Pike population is currently considered to be of somewhat above average quality (in terms of mean fish size with a Fishing Quality Index (FQI)** value of 192 – FMZ 18 FQI value of 151), with moderate opportunities to catch ‘Quality’ class fish. The population has moderate levels of recruitment, and relatively high fish abundance (catch rate (CUE) of 3.4 fish per net, in comparison to the zone’s mean CUE of 1.4 fish per net).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 39

3.5 Other Fish Species

The Fall Walleye Index Netting assessment protocol was not designed to assess populations of other fish species that were captured during this survey. Since these species were not targeted, no direct comparisons can be made with other individual populations, or with the broader FMZ 18 population, and as such, the following summarized biological attribute data should be interpreted with caution.

Smallmouth Bass

Abundance

The mean catch rate (CUE) for Smallmouth Bass in Upper Rideau Lake was 6.5 fish per net.

Size and Age

The size distribution of Smallmouth Bass captured in Upper Rideau Lake is summarized in Figure 20. The mean fork length of the catch was 377 (s.d. 85.9) mm. Typically, Smallmouth Bass reach a maximum size of 500 mm in Ontario (OMNR, 2012), with the average size being 300 mm (Holm et al., 2009), potentially indicating that a very strong component of very large fish, is present in Upper Rideau Lake.

10 n=71 fish Frequency(%) 5

Fork Length (mm)

Figure 20. Smallmouth Bass fork length distribution (2013 Upper Rideau Lake Modified FWIN assessment).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 40

The age distribution of Smallmouth Bass captured in Upper Rideau Lake is summarized in Figure 21. The mean age of the catch was 5 (2.0) years. None of the fish captured were close to reaching the approximate maximum age of Smallmouth Bass in Canada, of 15 years (Scott & Crossman, 1998).

n=65 fish

10 Frequency(%)

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Age (years)

Figure 21. Smallmouth Bass age distribution (2013 Upper Rideau Lake Modified FWIN assessment).

Growth and Maturity

Growth rates of Smallmouth Bass are dependent on habitat quality, food availability, and sex. The length at age of Smallmouth Bass captured in Upper Rideau Lake is summarized in Figure 22. The latter figure would suggest that Upper Rideau Lake’s population exhibits significantly higher growth rates, in comparison to FMZ 18, where it takes a Smallmouth Bass on average 5 years to reach 300 mm (OMNRF, 2014).

Sexual maturity is usually achieved by age 3-5 (male) and 4-6 (female) (Ridgway, 1988). Comparing the length at age 3-6 years (Figure 22) and the above fork length distributions (Figure 20) would indicate that a strong component of the fish captured in Upper Rideau Lake, were sexually mature.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 41

600

500

R² = 0.8356

400

300 n=65 fish

200 Fork LengthFork (mm)

100

0 0 2 4 6 8 10 12 14 16 18 Age (years) Figure 22. Smallmouth Bass length at age (2013 Upper Rideau Lake Modified FWIN).

Population dynamics are also influenced by annual mortality rates. The annual mortality rate from the Smallmouth Bass captured in Upper Rideau Lake is 59% (male and female) (calculated using a Catch Curve Analysis (i.e. descending slope of the Ln frequency distribution of the age class)). The condition of Smallmouth Bass sampled in the 2013 Upper Rideau Lake assessment is summarized as a reference point in time, in Figures 23, which shows the relationship between fork length and round weight.

3000

2500

R² = 0.9848

2000

1500 n=71 fish

1000 Round Weight (g)

500

0 0 100 200 300 400 500 600 Fork Length (mm) Figure 23. Smallmouth Bass length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 42

In summary, based on the fish captured during this assessment, Upper Rideau Lake’s Smallmouth Bass population is potentially considered to be of very high quality (in terms of mean fish size with a Fishing Quality Index (FQI)** value of 293 – FMZ 18 FQI value of 121-123 (based on Broad-scale Monitoring and Nearshore Community Index Netting data), with very abundant opportunities to catch ‘Quality’ and ‘Memorable’ class fish.

Largemouth Bass

Abundance

The mean catch rate (CUE) for Largemouth Bass in Upper Rideau Lake was 1.3 fish per net.

Size and Age

The size distribution of Largemouth Bass captured in Upper Rideau Lake is summarized in Figure 24. The mean fork length of the catch was 318 (s.d. 99.2) mm. Typically, Largemouth Bass reach a maximum size of 550 mm in Ontario (Brown et al., 2009), with the average size within FMZ 18 being 277 (s.d. 73.7) mm (OMNRF, 2014), potentially indicating that a strong component of relatively large fish, is present in Upper Rideau Lake.

40 35

25 20 n=14 fish

15 Frequency(%) 10 5 0

Figure 24. Largemouth Bass fork length distribution (2013 Upper Rideau Lake Modified FWIN assessment).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 43

The age distribution of Largemouth Bass captured in Upper Rideau Lake is summarized in Figure 25. The mean age of the catch was 5 (s.d. 2.7) years. None of the fish captured were close to reaching the approximate maximum age of Largemouth Bass in FMZ 18, of 15 years (OMNRF, 2014).

n=13 fish Frequency(%) 10

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Age (years)

Figure 25. Largemouth Bass age distribution (2013 Upper Rideau Lake Modified FWIN assessment).

Growth and Maturity

Growth rates of Largemouth Bass are dependent on habitat quality, food availability, and sex. The length at age of Largemouth Bass captured in Upper Rideau Lake is summarized in Figure 26. The latter figure would suggest that Upper Rideau Lake’s population exhibits higher growth rates, in comparison to provincial averages, where it takes a Largemouth Bass on approximately 5 years to reach 300 mm (Scott & Crossman, 1998).

Sexual maturity is usually achieved by age 3-4 (male) and 4-5 (female) (Scott & Crossman, 1998). Comparing the length at age 3-5 years (Figure 26) and the above fork length distributions (Figure 24) would indicate that a relatively strong component of the fish captured in Upper Rideau Lake, were sexually mature.

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600

500 R² = 0.8965

400

300

n=13 fish

200 Fork LengthFork (mm)

100

0 0 2 4 6 8 10 12 14 16 18 Age (years) Figure 26. Largemouth Bass length at age (2013 Upper Rideau Lake Modified FWIN).

Population dynamics are also influenced by annual mortality rates. The annual mortality rate from the Largemouth Bass captured in Upper Rideau Lake is 28% (male and female) (calculated using a Catch Curve Analysis (i.e. descending slope of the Ln frequency distribution of the age class)). The condition of Largemouth Bass sampled in the 2013 Upper Rideau Lake assessment is summarized as a reference point in time, in Figures 27, which shows the relationship between fork length and round weight.

3000

R² = 0.9911

2500

2000

1500

n=14 fish

1000 Round Weight (g)

500

0 0 100 200 300 400 500 600 Fork Length (mm) Figure 27. Largemouth Bass length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 45

In summary, based on the fish captured during this assessment, Upper Rideau Lake’s Largemouth Bass population is potentially considered to be of relatively high quality (in terms of mean fish size with a Fishing Quality Index (FQI)** value of 243 – FMZ 18 FQI value of 85 & 194 (based on Broad-scale Monitoring and Nearshore Community Index Netting data, respectively), with relatively abundant opportunities to catch ‘Quality’ and ‘Memorable’ class fish, bearing in mind the relatively small sample size (n=14 fish).

Pumpkinseed

Abundance

The mean catch rate (CUE) for Pumpkinseed in Upper Rideau Lake was the highest of all of the fish species captured during the assessment at 20 fish per net.

Size and Age

The size distribution of Pumpkinseed captured in Upper Rideau Lake is summarized in Figure 28. The mean fork length of the catch was 173 (s.d. 33.5) mm. Typically, Pumpkinseed reach a maximum size of approximately 300 mm in FMZ 18, with the average size being 151-166 mm (OMNRF, 2014), potentially indicating that a strong component of large fish, is present in Upper Rideau Lake.

45 40

30 25 20 n=100 fish

Frequency(%) 15 10 5 0

Fork Length (mm)

Figure 28. Pumpkinseed fork length distribution (2013 Upper Rideau Lake Modified FWIN assessment).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 46

The age distribution of Pumpkinseed captured in Upper Rideau Lake is summarized in Figure 29. The mean age of the catch was 4 (s.d. 1.3) years. A limited number of the fish captured had reached the maximum age of Pumpkinseed of 8-10 years (Scott & Crossman, 1998).

40 35

25 20 n=100 fish

15 Frequency(%) 10 5 0 1 2 3 4 5 6 7 8 9 10 11 12 Age (years)

Figure 29. Pumpkinseed age distribution (2013 Upper Rideau Lake Modified FWIN assessment).

Growth and Maturity

Growth rates of Pumpkinseed are dependent on habitat quality, food availability, and sex. The length at age of Pumpkinseed captured in Upper Rideau Lake is summarized in Figure 30. The latter figure would suggest that Upper Rideau Lake’s population exhibits higher growth rates, in comparison to FMZ 18, where it takes a Pumpkinseed on average 4 years to reach approximately 150 mm, the length which is believed to be the minimum size targeted for harvest by many anglers (OMNRF, 2014).

Sexual maturity is usually achieved by age 2 (male and female) (Scott & Crossman, 1998). Comparing the length at age 2 years (Figure 30) and the above fork length distributions (Figure 28) would indicate that a strong component of the fish captured in Upper Rideau Lake, were sexually mature.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 47

300 R² = 0.8038

250

200

150

100 n=100 fish Fork LengthFork (mm)

0 0 2 4 6 8 10 12 14 Age (years) Figure 30. Pumpkinseed length at age (2013 Upper Rideau Lake Modified FWIN).

Population dynamics are also influenced by annual mortality rates. The annual mortality rate from the Pumpkinseed captured in Upper Rideau Lake is 47% (male and female) (calculated using a Catch Curve Analysis (i.e. descending slope of the Ln frequency distribution of the age class). The condition of Pumpkinseed sampled in the 2013 Upper Rideau Lake assessment is summarized as a reference point in time, in Figures 31, which shows the relationship between fork length and round weight.

600

R² = 0.9619 500

400

300

n=100 fish Frequency(%) 200

100

0 0 50 100 150 200 250 300 Fork Length (mm) Figure 31. Pumpkinseed length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 48

In summary, based on the fish captured during this assessment, Upper Rideau Lake’s Pumpkinseed population is potentially considered to be of high quality (in terms of mean fish size with a Fishing Quality Index (FQI) ** value of 334 – FMZ 18 FQI value of 267-320 (based on Broad-scale Monitoring and Nearshore Community Index Netting data), with very abundant opportunities to catch ‘Quality’ and ‘Memorable’ class fish.

Bluegill

Abundance

The mean catch rate (CUE) for Bluegill in Upper Rideau Lake was 4.3 fish per net.

Size and Age

The size distribution of Bluegill captured in Upper Rideau Lake is summarized in Figure 32. The mean fork length of the catch was 179 (s.d. 25.6) mm. Typically, Bluegill reach a maximum size of approximately 240 mm in FMZ 18, with the average size being 123-151 mm (OMNRF, 2014), potentially indicating that a strong component of large fish, is present in Upper Rideau Lake.

20 n=28 fish Frequency(%) 10

Fork Length (mm)

Figure 32. Bluegill fork length distribution (2013 Upper Rideau Lake Modified FWIN assessment).

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 49

The age distribution of Bluegill captured in Upper Rideau Lake is summarized in Figure 33. The mean age of the catch was 4 (s.d. 1.4) years. No fish captured had reached the maximum age of Bluegill of 8-10 years (Scott & Crossman, 1998).

15 n=28 fish

Frequency(%) 10

0 1 2 3 4 5 6 7 8 9 10 11 12 Age (years)

Figure 33. Bluegill age distribution (2013 Upper Rideau Lake Modified FWIN assessment).

Growth and Maturity

Growth rates of Bluegill are dependent on habitat quality, food availability, and sex. The length at age of Bluegill captured in Upper Rideau Lake is summarized in Figure 34. The latter figure would suggest that Upper Rideau Lake’s population exhibits higher growth rates, in comparison to FMZ 18, where it takes a Bluegill on average 4 years to reach approximately 150 mm, the length which is believed to be the minimum size targeted for harvest by many anglers (OMNRF, 2014).

Sexual maturity is usually achieved by age 2-3 (male) and 3-4 (female) (Scott & Crossman, 1998). Comparing the length at age 2-4years (Figure 34) and the above fork length distributions (Figure 32) would indicate that a strong component of the fish captured in Upper Rideau Lake, were sexually mature.

2013 Upper Rideau Lake Modified Fall Walleye Index Netting Assessment Report - OMNRF Kemptville District Page 50

300

R² = 0.6345

250

200

150

100 n=28 fish Fork Length(mm)Fork

0 0 2 4 6 8 10 12 Age (years) Figure 34. Bluegill length at age (2013 Upper Rideau Lake Modified FWIN).

Population dynamics are also influenced by annual mortality rates. The annual mortality rate from the Bluegill captured in Upper Rideau Lake is 35% (male and female) (calculated using a Catch Curve Analysis (i.e. descending slope of the Ln frequency distribution of the age class)).

The condition of Bluegill sampled in the 2013 Upper Rideau Lake assessment is summarized as a reference point in time, in Figures 35, which shows the relationship between fork length and round weight.

500 450 R² = 0.9487 400

350 300 250 200 n=28 fish

Round Weight (g) 150 100 50 0 0 50 100 150 200 250 300 Fork Length (mm) Figure 35. Bluegill length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment).

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In summary, based on the fish captured during this assessment, Upper Rideau Lake’s Bluegill population is potentially considered to be of high quality (in terms of mean fish size with a Fishing Quality Index (FQI) ** value of 300 – FMZ 18 FQI value of 156-235 (based on Broad-scale Monitoring and Nearshore Community Index Netting data), with abundant opportunities to catch ‘Quality’ and ‘Memorable’ class fish.

Rock Bass

Abundance

The mean catch rate (CUE) for Rock Bass in Upper Rideau Lake was 19.5 fish per net.

Size and Age

The size distribution of Rock Bass captured in Upper Rideau Lake is summarized in Figure 36. The mean fork length of the catch was 174 (s.d. 48.9) mm. Typically, Rock Bass reach a maximum size of 254 mm in Ontario, with the average size being 152-203mm (Scott & Crossman, 1998), potentially indicating that a relatively strong component of very large fish, is present in Upper Rideau Lake. It is reported that Rock Bass weights rarely exceed ½ pound (227 g) (Scott & Crossman, 1998), yet several individuals captured during this assessment were in excess of this weight, including a number over 1 pound (454 g) (Figure 39).

10 n=97 fish Frequency(%) 5

Fork Length (mm)

Figure 36. Rock Bass fork length distribution (2013 Upper Rideau Lake Modified FWIN assessment).

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The age distribution of Rock Bass captured in Upper Rideau Lake is summarized in Figure 37. The mean age of the catch was 4 (s.d. 1.7) years. A few fish captured were close to reaching the approximate maximum age of Rock Bass, of 10-12 years (Scott & Crossman, 1998).

15 n=87 fish

Frequency(%) 10

0 1 2 3 4 5 6 7 8 9 10 11 12 Age (years)

Figure 37. Rock Bass age distribution (2013 Upper Rideau Lake Modified FWIN assessment).

Growth

Growth rates of Rock Bass are dependent on habitat quality, food availability, and sex. The length at age of Rock Bass captured in Upper Rideau Lake is summarized in Figure 38. The latter figure would suggest that Upper Rideau Lake’s population exhibits somewhat higher growth rates, in comparison to Michigan Lakes (n=126) and North Wisconsin Lakes (n=6), which should approximate the age-length relation in southern Canada (Scott & Crossman, 1998).

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300

R² = 0.8038

250

200

150

n=87 fish

100 Fork LengthFork (mm)

0 0 2 4 6 8 10 12 Age (years) Figure 38. Rock Bass length at age (2013 Upper Rideau Lake Modified FWIN).

Population dynamics are also influenced by annual mortality rates. The annual mortality rate from the Rock Bass captured in Upper Rideau Lake is 39% (male and female) (calculated using a Catch Curve Analysis (i.e. descending slope of the Ln frequency distribution of the age class)).

The condition of Rock Bass sampled in the 2013 Upper Rideau Lake assessment is summarized as a reference point in time, in Figures 39, which shows the relationship between fork length and round weight.

600

R² = 0.9851

500

400

300

200 n=97 fish Round Weight (g)

100

0 0 50 100 150 200 250 300 Fork Length (mm) Figure 39. Rock Bass length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment).

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In summary, based on the fish captured during this assessment, Upper Rideau Lake’s Rock Bass population is potentially considered to be of high quality (in terms of mean fish size with a Fishing Quality Index (FQI)** value of 178 – FMZ 18 FQI value was not calculated), with very abundant opportunities to catch ‘Quality’ and ‘Memorable’ class fish.

Brown Bullhead

Abundance

The mean catch rate (CUE) for Brown Bullhead in Upper Rideau Lake was 4.1 fish per net.

Size and Age

The size distribution of Brown Bullhead captured in Upper Rideau Lake is summarized in Figure 40. The mean total length of the catch was 265 (s.d. 33.8) mm. Typically in Canada, Brown Bullheads reach an average size of 203-356 mm (Scott & Crossman, 1998), potentially indicating that Upper Rideau Lake’s population is in line with the average size, for the species.

40 35

30 25 20

15 n=31 fish Frequency(%) 10 5 0

Total Length (mm)

Figure 40. Brown Bullhead total length distribution (2013 Upper Rideau Lake Modified FWIN assessment).

The Brown Bullheads captured in Upper Rideau Lake Modified FWIN assessment were not aged.

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The condition of Brown Bullhead sampled in the 2013 Upper Rideau Lake assessment is summarized as a reference point in time, in Figures 41, which shows the relationship between total length and round weight.

900

800 R² = 0.9387

700

600 500 400 n=31 fish

300 Round Weight (g) 200 100 0 0 50 100 150 200 250 300 350 400 Total Length (mm) Figure 41. Brown Bullhead length to weight relationship (2013 Upper Rideau Lake Modified FWIN assessment).

In summary, based on the fish captured during this assessment, Upper Rideau Lake’s Brown Bullhead population is potentially considered to be of high quality (in terms of mean fish size with a Fishing Quality Index (FQI)** value of 277 – FMZ 18 FQI value was not calculated), with very abundant opportunities to catch ‘Quality’ class fish.

Other species

Abundance

The mean catch rate (CUE) for all other fish species is summarized in Section 3.1.

Size and Age

Due to low sample sizes, all other fish species data were not fully analyzed. The size distribution ranges of all other fish species captured and sampled in Upper Rideau Lake is summarized in Table 7.

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Table 7. Size ranges of other fish species captured in 2013 Upper Rideau Lake Modified FWIN assessment. Fish Species Mean Total Mean Round Total Length Round Weight Length (mm) Weight (g) Range (mm) Range (g) Alewife 107 (n=8) 15 (n=5) 103-111 14-15 White Sucker 477 (n=11) 1493 (n=11) 451-572 1025-3050 Yellow Bullhead 237 (n=3) 242 (n=3) 215-273 175-325 Golden Shiner 163 (n=6) 72 (n=6) 103-202 12-150 Black Crappie 216 (n=4) 273 (n=4) 118-299 190-500 Common Carp 494 (n=2) 1925 (n=2) 488-499 1750-2100 Silver Redhorse 544 (n=1) 2025 (n=1) n/a n/a Burbot 628 (n=1) 1400 (n=1) n/a n/a

The age distribution ranges of all other fish species captured and sampled in Upper Rideau Lake is summarized in Table 8.

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Table 8. Age ranges of other fish species captured in 2013 Upper Rideau Lake Modified FWIN assessment.

Fish Species Mean Age (years) Age Range (years) Alewife n/a n/a White Sucker 5 (n=9) 4-9 Yellow Bullhead n/a n/a Golden Shiner n/a n/a Black Crappie 2 (n=4) 1-4 Common Carp 8 (n=2) 7-9 Silver Redhorse 8 (n=1) n/a Burbot 12 (n=1) n/a

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4.0 CONCLUSION & RECOMMENDATIONS

4.1 Conclusion

The data collected during the 2013 Upper Rideau Lake Modified FWIN assessment has provided more comprehensive and updated information for guiding future fisheries management decisions and efforts.

Walleye

It is quite apparent from the composition of the fish captured during the assessment, in combination with the average size of spawning fish captured during the Westport Area Outdoor Association’s gametes collections in recent springs, that there is now likely next to no population recruitment occurring. Only large mature fish (with at least 62% of the catch originating from the last stocking efforts (2000-2001) – i.e. a number of the initial fish captured were not inspected for clips) are making up the bulk of the population structure, which can also be interpreted as a sign of a heavily stressed fishery.

As mentioned in this report’s Introduction section, the previous (1980’s) collapse of the Walleye population was believed to have been associated with:

 Nutrient enrichment from poor quality septic systems (causing excessive eutrophication) which led to increased abundance of aquatic vegetation and declining levels of dissolved oxygen;

 Predation and competition by other fish species; and

 Deterioration of spawning sites with consequent Walleye reproduction failure.

The first and third bullet points have been addressed to some extent (The Town of Westport constructed a new sewage treatment plan in the late 1990’s; The Westport and Area Outdoor Association rehabilitated spawning sites), however the second bullet has not. The latter may have been a supporting factor in early conclusions made following review and analysis of post- fall fingerling stocking (2000-2001) assessment data: “that the long-term viability of a sustainable, self-reproducing population was questionable”(Burn, 2003).

The top 5 species (Pumpkinseed, Rock Bass, Yellow Perch, Smallmouth Bass and Bluegill) which made up the majority composition (combined total of 82%) of the fish captured during the 2013 assessment, are all competitor or predator species of Walleye, for the latter’s various early life

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stages. Another major compounding factor is the shear amount of suitable, shallow, warm water habitat immediately adjacent to the major Walleye spawning sites, for all of these competitor/predator species, forcing young Walleye fry to immediately “run (drift) the gauntlet” after emerging.

Even though the current catch rate of 1.9 fish per net would categorize the lake’s Walleye Population to be of low to moderate abundance level, in comparison to the zone’s (FMZ 18) mean catch rate of 3 fish per net, with evidence of extremely poor recruitment, with the mean age of the fish captured during the assessment and with the mean age showing up at the main spawning sites in recent springs, very low fish abundance levels (i.e. remnant population) can be forecasted in the near future.

Recent size regulation changes (i.e. Harvestable Slot Size: 40 – 50 cm) that were implemented, starting in January 2013, primarily to protect the larger size, mature females, likely won’t be effective at sustaining this particular population given the mean age of the fish captured and the soon to be expected, residual abundance levels.

Yellow Perch

It is quite apparent from the composition of the fish captured during the assessment, in combination with the average size of fish captured and reported by the local Commercial Fisherman, that the lake’s Yellow Perch population is very healthy and is not showing any signs of heavy mortality.

The mean catch rate, size and age are all significantly higher than zone averages.

The above-mentioned recent collapse of the Walleye fishery has likely significantly reduced the level of predation mortality on the species, with the balance shifting to Yellow Perch as a contributing predator species of the Walleye population’s early life stages, in combination with other abundant warm water, centrarchid fish species.

Northern Pike

The composition of the fish captured during the assessment would indicate that the lake’s Northern Pike population is relatively healthy, with a number of somewhat larger size fish present.

The mean catch rate, size, age and growth rates are all higher than zone averages.

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Other Fish Species

As indicated in section 3.5, the Fall Walleye Index Netting assessment protocol was not designed to assess populations of other fish species that were captured during this survey. Since these species were not targeted, no direct comparisons can be made with other individual populations, or with the broader FMZ 18 population, and as such, the data should be interpreted with caution.

That being said, it would appear that this lake likely has a tremendous warm water community fishery, for the following species: Smallmouth Bass, Pumpkinseed, Bluegill, Rock Bass, and potentially to some extent, Largemouth Bass. The latter conclusion is based on biological attributes and on the mean catch rates of the above-mentioned species, using a protocol that would not typically yield these levels of capture.

The above also further supports the theory that the major contributing factor to the recent (and potentially the previous) collapse of the lake’s Walleye population is indeed predation and competition by other fish species. This latter factor likely has, and will continue to have incremental impacts, due to climate change favouring warm water fish communities.

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4.2 Recommendations

 Shift primary fisheries management focus from a cool water fishery to a warm water fishery; or

 Consider rehabilitating the lake’s Walleye fishery if, and only if all of the following contributing factors (i.e. the cause of the decline) to the Walleye population collapse can be addressed:

o First and foremost, predation and competition by other fish species – significant short-term warm water fish community management efforts (and long-term maintenance) would be required to address what has caused the Walleye population decline in the first place. The presence of too many panfish, Bass and Northern Pike may prevent recovery because of their ability to predate on the young stocked fish (OMNRF, 2014);

o Nutrient enrichment – nutrient sources would need to be re-evaluated to determine if this water quality factor is still considered to be a significant contributor to the population decline, or a future population in rehabilitation, as changes in habitat (including Dissolved Oxygen levels) may limit recovery; and

o Spawning habitat – known spawning sites would need to be re-assessed (and additional spawning habitat and/or spawning assessments may need to be conducted).

 If the latter option is pursued, a fishery rehabilitation plan will need to be developed to assist in the recovery of the population. A component of the fishery rehabilitation plan will be a stocking plan that outlines stocking duration, strain/source, and age/size, stocking rate, marking, disease /invasive species transfer prevention, stocking methods, assessment and evaluation of project success.

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REFERENCES

Brown, T.G., Runciman, B., Pollard, S., and Grant, A.D.A. 2009. Biological synopsis of largemouth bass (Micropterus salmoides). Can. Manuscr. Rep. Fish. Aquat. Sci. 2884: v + 27p.

Burns, C. 2003. The State of Upper Rideau Lake: Fisheries Assessment Report 1982-2001. 57 pp.

Holm, E., M. Burridge, and N. Mandrak. 2009. The ROM fieldguide to freshwater fishes of Ontario. Royal Ontario Museum, Toronto, Ontario. 462 p.

Lee, G. 1995. Sub-watershed survey of Upper Rideau Lake: Stage 1. Upper Rideau Lake Association. Westport, Ontario. 92 pp.

Morgan, G.E. 2002. Manual of Instructions. Fall Walleye Index Netting (FWIN): Ontario Ministry of Natural Resources – Percid Community Synthesis, Diagnostics and Sampling Standards Working Group. 40pp.

Ontario Ministry of Natural Resources (OMNR). June 1, 2005. Fact Sheet – The Fishery of Upper Rideau Lake. 2 pp.

Ontario Ministry of Natural Resources (OMNR). 2012. Fish Ontario: Smallmouth Bass.

Ontario Ministry of Natural Resources and Forestry (OMNRF). 2014. Background Information to 2014 Fisheries Management Plan for Fisheries Management Zone 18. 205pp.

Ridgway, M.S. 1988. Developmental stage of offspring and brood defense in Smallmouth Bass (Micropterus dolomieu). Canadian Journal of Zoology 66: 1722-1728.

Scott, W.B., and Crossman, E.J. 1998. Freshwater Fishes of Canada. Galt House Publications, Oakville, Ontario. 966pp.

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APPENDIX A

Set and Lift Data for 2013 Upper Rideau Lake Modified FWIN Assessment

Effort Depth (m) Time (hrs) Status 1= ok 2= Stratum Water Effort twisted/ 2-5m or Temp # tampered min max 5-15m Start End Duration ('C) 13-10- 13-10- 21 22 1 1 2.2 3.1 2-5 1055 1200 2505 14.4 13-10- 13-10- 21 22 2 1 2.1 2.9 2-5 1038 950 2312 14.2 13-10- 13-10- 21 22 3 1 5 5.4 5-15 1110 1340 2630 14.4 13-10- 13-10- 23 24 4 1 2.3 2.6 2-5 1110 935 2225 14 13-10- 13-10- 22 23 5 2 (twist) 14.1 14.5 5-15 1510 1320 2210 14.6 13-10- 13-10- 22 23 6 1 2.9 5 2-5 1400 1150 2150 14.5 13-10- 13-10- 22 23 7 1 2.5 3.2 2-5 1010 940 2330 14 13-10- 13-10- 23 24 8 1 6.7 10.9 5-15 1120 1100 2340 14.2 13-10- 13-10- 23 24 9 1 6.5 12.5 5-15 1330 1300 2330 14.4 13-10- 13-10- 24 25 11 1 6.2 14.9 5-15 1320 1330 2410 13.8 13-10- 13-10- 24 25 13 1 2 5 2-5 1300 1120 2220 13.4 13-10- 13-10- 24 25 15 1 6.2 13.2 5-15 930 930 2400 13.8

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