Limnology and Fisheries the Saskatchewan River In

Fisheries Report No. 6

Limnology and Fisheries

of The Saskatchewan River In Saskatchewan

Edward B. Reed

Department of Zoology, Colorado State University formerly Fisheries Biologist, Fisheries Branch Saskatchewan Department of Natural Resources 1962

Fisheries Branch DEPARTMENT OF NATURAL RESOURCES Province of Saskatchewan

Hon. A. G. KUZIAK J. W. CHURCHMAN Minister -83P). Deputy Minister This bulletin may be reproduced else- where provided due credit is given to the author and the agencies concerned. CONTENTS

Page Introduction ...... 5

Acknowledgments S 5

Physical Conditions ...... 6

Water Chemistry ...... 13

Biological Factors 24

Plankton ...... 24

Coliform Bacteria ...... 25

Bottom Fauna ...... 27

Fish Fauna 29

Fish Populations and Utilization ...... 31

Fish Growth ...... 36

Fish Food 39

Fish Parasites ...... 40

Pollution 41

Summary and Conclusions ...... 45

References ...... 46 Introduction

The Saskatchewan River is important to the people of Saskatchewan as a source of water for domestic use both by man and his livestock; for industrial purposes; and as a resource for recreation—angling, picnicking and boating. In January, 1957, the Fisheries Branch of the Department of Natural Resources began a two-year survey of the Saskatchewan River system within the Province of Saskatchewan. The principal questions to be answered were: what is the fisheries resource of the Saskatchewan River, how is it utilized, and what is the condition of the river in regard to pollution? The combined length of the three principal portions of the Saskatche- wan River in Saskatchewan is nearly 900 miles. To investigate in detail all parts of so great a river system was beyond the scope of this survey. The general attack upon the problem was to make detailed observations at selected stations, usually near ferry crossings or bridges. The stations at Saskatoon, Prince Albert, and Borden were those most frequently sampled; however, other stations (Figure 1) were visited at least twice during the survey. Field work extended from January, 1957, through September, 1958. Mr. Alan Derbawka assisted with field work in the summer of 1957. Mr. James Dosman was field assistant in 1958. The detailed data and the biological collections are on file at the Fisheries Laboratory, University of Saskatchewan, Saskatoon.

Acknowledgments

It is a pleasure to acknowledge the support of the Director of Fisheries, G. E. Couldwell and others of the Department of Natural Resources staff in Prince Albert, particularly Fisheries Supervisor P. H. Edwards for assistance in securing winter observations. The co-operation of Conservation Officers in districts adjacent to the rivers was much ap- preciated. Fisheries Biologist F. M. Atton assisted in organizing the investigation and made valuable suggestions. The late Dr. D. S. Rawson, Department of Biology, University of Saskatchewan, gave advice and stimulating counsel. Physical Conditions Drainage basin The headwaters of both the North and South Saskatchewan Rivers rise in the Rocky Mountains along the British Columbia-Alberta boundary. Eastward from the Alberta foothills, the basin of the Saskatchewan is underlain by Palaeozoic and Mesozoic strata covered by glacial drift of considerable depth. Present day physiographic features are mostly the result of events occurring during deglaciation. The two principal types of river bed in areas of strong current are hard sand and gravel or small cobblestones. Reaches of slack current have sub-strata of soft sand or mud. Shifting sandbars are prominent features of the North and South Saskatchewan Rivers and are particularly evident on the South in the stretch from Riverhurst to Dundurn and on the North in the Maymont and Borden areas. Sand bottom areas of considerable extent are found in

PRINCE ALBERT

-J

SWIFT CURRENT CREEK

Fig. 1. Map of sampling stations on North and South Saskatchewan Rivers. 1. Frenchman Butte 17. Empress 2. North Battleford 18. Leader ferry 3. Maymont 19. Saskatchewan Landing 4. Borden 20. Swift Current Creek 5. Petrofka 21. Riverhurst 6. Crutwell 22. Elbow 7. Prince Albert 23. Outlook 8. Cecil 24. Yorath Island 9. Forks of North and South 25. Saskatoon Saskatchewan Rivers 26. Clarkboro 10. Fort a la Come 27. Hague ferry 11. Nipawin 28. St. Louis 12. Dept. Nat. Res. boathouse 29. Fenton 13. Cumberland Lake 30. Weldon 14. Old Channel 31. Torch River 15. Empress ferry, So. Sask. River 32. Little Red River 16. Red Deer River 33. Battle River the Saskatchewan between Nipawin and Cumberland House. Inter- spersed in the sandy areas are short stretches of rapids where the rivers cross bars of cobblestones. For the Saskatchewan basin as a whole, the climate is temperate and precipitation varies from moderate to arid (Thomas, 1956). Much of the drainage area is covered by brown and darkbrown prairie soils, and black soils, all of which have a high degree of natural fertility (Hogg, et al., 1952). Areas of the drainage basins are given by Thomas (1956) as follows: Alberta Saskatchewan Total North Saskatchewan 36,050 sq. mi. 22,650 sq. mi. 58,700 sq. mi. South Saskatchewan 44,605 sq. mi. 21,365 sq. mi. 65,970 sq. mi. Saskatchewan 0 sq. mi. 23,180 sq. mi. 23,180 sq. mi. Thomas (1956) stated that the Saskatchewan River system drains 27 per cent of the land area in the Province of Saskatchewan and that 42 per cent of the province's population lives in the drainage basin. Comparable figures for Alberta are 32 per cent of the area upon which 85 per cent of the people live. The total number of people living in the Saskatchewan River drainage was estimated by Thomas to be 1,161,300.

Volume and Depth Dennis and Challies (1916) noted that the chief characteristic of rivers that rise in the Rocky Mountains is the great variation between maximum and minimum flow, reporting that the ratio may be as great as 200 to 1. Monthly discharge records for the years 1912-15 made at Prince Albert on the North Saskatchewan and at Saskatoon on the South indicate that two peaks of high water usually occur each year. The first, in April, is due to runoff of snow melt on the prairies. The second peak, usually occurring in June but sometimes in July or August, indicates the arrival of meltwater from the mountainous headwater area (Hogg, et. al., 1952). Thus the flood conditions in any one year will depend upon snowfall on the prairies and in the mountains, and upon the amount and time of occurrence of summer rainfall. Daily flow measurements of the North Saskatchewan made at French- man Butte and at Prince Albert, and of the South Saskatchewan made at Saskatoon for the period October 1, 1956, to September 30, 1958, have been made available by the Water Resources Branch, Department of Northern Affairs and National Resources, Calgary, Alberta. Recordings made on the Saskatchewan at Nipawin in the periods March 1 to October 31, 1957, and March 1 to October 31, 1958, were also furnished by the Water Resources Branch. Flow data for the four stations are summarized in Table 1. The highest ratio of maximum to minimum for a calendar year was 53 to 1 at Frenchman Butte in 1956; however, the ratio of high water in June, 1957, to low water of December, 1956, was over 100 to 1. Prairie runoff and mountain snow melt tended to blend together in both years of the survey; hence in Figures 2 and 3 bimodal curves of flow are not clearly evident. The histogram representing the South in 1957 (Figure 3) sug, gests peaks in April and June separated by a small decline in May. Maximum flow in the South was similar in the two years, but maximum flow of the North was much higher in 1958 than in 1957 (Figures 2 and 3). In both the North and South rivers, continual daily fluctuations are superimposed upon the larger seasonal variations, illustrated by the following measurements made at Saskatoon: 7 Table 1.—Summary of flow data for four stations in the Saskatchewan River system in Saskatchewan. Preliminary information supplied by Department of Northern Affairs and National Resources, Calgary, Alta.

Average Maximum Minimum Total discharge Total discharge Drainage monthly observed observed for station for station area discharge discharge discharge during period, during period. Station and period of observations sq. mi. sec.-ft. date and sec.-ft. date and sec.-ft. sec.-ft. acre-ft. Frenchman Butte (North Saskatchewan) Oct. 1/56-Sept. 30/57...... 22,000 6,356 June 13 December 12 2,319,952 4,601,000 23,330 436 Oct. 1/57-Sept. 30/58...... 8,756 July 2 February 26 3,195,770 6,338,000 48,950 1,050 Prince Albert (North Saskatchewan) : Oct. 1 /56-Sept. 30/57...... 46,100 6,708 April 20 December 26 2,448,611 4,857,000 25,320 636 Oct. 1/57-Sept. 30/58 9,027 July 6 March 28 3,294,740 6,535,000 46,810 1,010 Saskatoon (South Saskatchewan) : Oct. 1/56-Sept. 30/57...... 50,900 7,489 May 30 January 28 2,733,418 5,422,000 30,200 802 Oct. 1/57-Sept. 30/58...... 8,532 April 17 January 3 3,114,290 6,177,000 30,120 1,320 Nipawin (Saskatchewan) : Mar. 1/57-Oct. 31/57...... 101,300 19,500 May 30 March 4 4,778,570 9,477,000 46,210 3,950 Mar. 1 /58-Oct. 31/58...... 25,150 July 7 March 10 6,160,660 12,220,000 59,790 4,260 Date Discharge c.f.s. Date Discharge c.f.s. July 4, 1957 ...... 14,120 Dec. 25, 1956 ...... 2,070 July 5, 1957 ...... 14,300 Dec. 26, 1956 ...... 1,760 July 6, 1957 ...... 13,990 Dec. 27, 1956 ...... 2,270 July 7, 1957 ...... 14,240 Dec. 28, 1956 ...... 2,400 July 8, 1957 ...... 15,930 Dec. 29, 1956 ...... 2,270 Dec. 30, 1956 ...... 2,560 Rapid changes in flow frequently occur, as is shown by the following measurements taken at Saskatoon: April 14, 1957 ...... 15,390 c.f.s. April 15, 1957 ...... 22,500 c.f.s. April 16, 1957 ...... 14,470 c.f.s. Rapid changes of water level in spring are often associated with ice damming the river. However, at Frenchman Butte the North Saskatche- wan rose from 24,720 c.f.s. on July 1, 1958, to 47,040 c.f.s. the next day. This was due to arrival of flood waters from higher elevations in the drainage basin and not to ice damming. A similar sharp rise in water level at Prince Albert occurred on July 5, indicating that about four days were required for the crest to move from Frenchman Butte to Prince Albert. Except in flood periods, the North and South branches and the Sask- atchewan itself are rather shallow rivers usually measuring six to ten feet in depth. The deepest sounding, 26 ft., made on the South Saskatchewan was taken at the bridge abuttment on the east side of the river at Outlook, August 30, 1957. A hole 40 ft. in depth was sounded on the Old Channel

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FIG. 2. Discharge of the North Saskatchewan River at Frenchman Butte, October 1, 1950, to September 30, 1958. Stippled bars are the monthly minimum; open bars, the maximum; cross lines, the mean, 9 September, 1958.Depthvariedfromsixtotenfeetinaseriesofsoundings about onemileaboveElmPortageintheCumberlandHousearea, made intheSouthSaskatchewanoverathreetofourmilereachabove the Clarkboroferrycrossing,June12,1958. Fig. Fig. 2 1 1 5

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Mean monthlytemperatures, North Saskatchewan Rivers, 1, mum; openbars,themaximum;crosslines,mean. Discharge oftheSouthSaskatchewanRiveratSaskatoon,October 1958, J THOUSANDS, C. F.S. 22 26 30 1 1 1 I 2 0 4 6 8

F to September IM 0 I A IM 1957. 80, 1958. A MJJAS0 ^ I JI

1 0 Stippled barsarethemonthlymini- JIA ^

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A and 1 MJJAS 0 South I N ID ---- 50 68 59 41 32 F °

Table monthly temperatures, North and South Saskatchewan 2.-Mean Rivers.

South North 1957 1958 1957 1958

January 0.4°C. 0.1°C. 0.1°C. 0.0°C. February 0.5 0.1 0.3 0.0 March 0.9 0.7 0.3 0.4 April 3.9 -- 3.7 -- May 17.1 9.0 13.0 -- June 19.8 16.6 18.3 20.5 July 22.3 20.8 22.2 20.9 August 1_9.' 19.3 20.5 20.5 September 16.8 -- 11.5 14.75 October 9.6 3.0 -- November 0.6 0.6 December 0.3 -- 0.3 --

Water temperature Two cycles of temperature were observed, yearly and diurnal. Tem- peratures recorded have been averaged (Table 2) for each month and graphed for 1957 (Figure 4) to indicate the general pattern of warming. In the spring after the ice had moved out, water temperatures rose rapidly; a period of less rapid warming followed. Maximum temperatures were recorded in both years in mid-July. A moderate decline in temperature through August was followed by a rapid drop to freeze-up in October or November. The curves in Figure 4 suggest that the North Saskatchewan warmed more slowly and cooled more rapidly than did the South in 1957. Data collected in 1958 indicate a similar trend. Rapid warming in spring is aided by the turbid condition of the water, the dark clay and silt particles absorbing heat from solar insolation. Observed maximum temperatures were as follows; South North 1957 24.0°C. Lemsford Ferry, 1957 22.5°C. Maymont and July 25. Petrofka Ferries, July 9 and 11. 1958 26.9°C. Empress Ferry, 1958 21.8°C. Borden Bridge, July 22. July 18. Surface temperatures were taken at one- or two-hour intervals throughout the day on several occasions. The largest observed variation within one 24-hour period was 5.4°C. in the South Saskatchewan River at Empress Ferry, July 21-22, 1958. Surface temperatures usually reached the daily maximum in late afternoon and were at a minimum in the early morning. Water temperatures tended to follow changes in the air temperature (Figure 5), declining at night as heat was lost by radiation. With the cessation of solar insolation at sundown, a sudden drop in surface temperature usually occurred. Heat loss by radiation during the night was more uniform than the sudden loss which occurred in late afternoon. That insolation, and not heat transfer from the atmosphere, was the more important in heating the surface water is shown by the temperature curve for the station at Gabriel Ferry (Figure 5). Between midnight and 8 a.m. the air temperature rose and the water temperature declined steadily. About 9 a.m. clouds which had obscured the sun dispersed; both air and water temperatures rose. No instances of thermal stratification were noted. Both the North and South are turbulent rivers and the water in each is well mixed. Tern- 11 I \ • C. F

BORDEN —. 79 26 —1 SEP T.9-I0 24 _. 75 I I — _ 22 — — — 72 — — 20 — — — 68 I _ — I 64

— 1 7-- I 1 6 1 I I 61 \ I _ _ 1 — .I \ 1 I i I 4 _ _ 1 I _ \ / - 57 `.." I liii_ _ EMPRESS I I 2 54 — — GABRIEL — JUL.21- 22 I _ — JU L.5I- AUG I —1 — I I I I I I I I I I I I I I • I I I I I I 8 M4 8 N 4 8 4 8 M48 N 4 8 N 4 8 M 4 8 Fig. 5. Diurnal variation in water and air temperature at two stations on the South Saskatchewan and one on the North Saskatchewan Rivers, 1958. M, midnight; N, noon. peratures were observed to fluctuate from moment to moment if a ther- mometer was held in the surface water at one location for several minutes. Water masses which may have received differential heating in back waters or other protected areas before being mixed into the general flow would account for the observed fluctuations. Fluctuations of this kind did not exceed one degree Centigrade, and most were less. Suspended material and turbidity The amount of materials held in suspension by the rivers was estimated in two ways. First, a measured volume of river water was passed through a weighed membrane filter capable of retaining particles of bacterial size. The filter and contents were dried, weighed, ashed, and the residue weighed. Total suspended material and percentage of mineral matter could then be determined. Second, measured samples of unfiltered and filtered river water were evaporated to dryness at 100°C. in weighed crucibles. After evaporation the crucibles were reweighed. The filtered samples were considered to contain dissolved solids and the unfiltered, total solids. The difference was assumed to be due to suspended material. The greatest amount of suspended material would be expected during times of high water when silt, sand, and organic debris are being washed into the river by runoff. The seasonal trend in the sediment load of the North Saskatchewan River is indicated by the following membrane filter determinations: Total suspended Per cent Date solids, mg/1. mineral content April 26, 1957 340 45.3 May 3 518 32 . 4 June 5 244 49 . 2 June 21 446 39 . 5 August 2 71 28 . 1 (One mg./1. is approximately equivalent to 1 pound of suspended solids per 100,000 Imperial gallons of water). An interesting contrast between 12 high and low loads of suspended solids was afforded by two observation made at Fenton on the South Saskatchewan River. On May 14, 1957, the total suspended solids were 1,032 mg./1. On August 6, the amount was 133 mg./1. The South Saskatchewan at Saskatoon was observed to contain 1,300 mg./1. of suspended solids on April 8, 1958, and on this date the discharge was roughly 10,000 c.f.s. Combining this information, it may be estimated that 8,350 tons of suspended material were being carried past Saskatoon each 24 hours.

Water Chemistry Methods Sulphate, chloride, and hardness determinations were made in the laboratory; other chemical analyses were usually made in the field. Frequently all analyses were made on the day of sampling, but occas- ionally several days elapsed between date of sampling and analysis. Samples which had to be kept several days before analysis were preserved from bacterial action with chloroform. Alkalinity was determined by the methyl orange indicator method (American P.H.A., 1955). Chloride was measured volumetrically (Theroux, et. al., 1943). Sulphate was determined volumetrically (Theroux, et. al., 1943) on samples taken prior to April 1, 1958, after which time a titrimetric method (American P.H.A., 1955) was used. Hydrogen ion concentration was measured either colon- metrically or with a glass electrode. Dissolved oxygen was usually determined by the Miller method (Miller, 1914). Some difficulty was encountered in reaching a satisfactory end point for oxygen determinations made in turbid water. This was overcome by drawing the water sample through a wad of cotton held over the submerged end of a pipette thus filtering out the silt particles. Hardness was measured by a compleximetric titration method (Amer- ican P.H.A., 1955). Dissolved solids were measured by evaporation at 100° C. Samples for chemical analyses were filtered through two thick- nesses of Reeve Angel No. 202 filter paper. Alkalinity The levels of alkalinity, sulphate, chloride, and hardness fluctuated throughout the year in the North Saskatchewan (Figure 6 and Table 3) and the South Saskatchewan (Figure 7 and Table 4) Rivers. The curves are a composite of several stations, and thus indicate general trends. Normal carbonate alkalinity in the South Saskatchewan varied from zero to 16 p.p.m. and bicarbonate ranged from 92 to 250 p.p.m. In the North Saskatchewan, corresponding values were zero to 20 and 90 to 354 p.p.m. Bicarbonate content increased sharply in both rivers under the winter ice cover; concurrently hardness increased, and the water became more acidic. Hardness is due primarily to calcium and magnesium, usually as bicarbonates. Increase in both hardness and bicarbonate content in conjunction with an increase in hydrogen ions suggests that carbon dioxide from the decomposition of organic material was forming carbonic acid in the water. The carbonic acid was able to bring the water insoluble carbonates of magnesium and calcium into solution as water soluble bicarbonates. The calcium and magnesium content in the South Saskatchewan during winter was about double that of summer, as the following determinations made by the Chemistry Department, University of Saskat- chewan indicate: 13 South Sask. South Sask. North Sask. Clarkboro Saskatoon Borden February 4, 1957 June 5, 1957 February 6, 1957 Calcium ...... 74.2 p.p.m. 36.8 p.p.m. 115.8 p.p.m. Magnesium ...... 24.7 p.p.m. 14.9 p.p.m. 35.5 p.p.m. Sodium (by difference) ...... 34.0 p.p.m. 7.7 p.p.m. 15.9 p.p.m. Sodium (by analysis) ...... — 5.3 p.p.m. — Data given by Thomas (1956) showed that in a series of analyses of North Saskatchewan River samples taken at Prince Albert, calcium content

1 J I F ' MIA M J I J A 0 N Fig. 8. Fluctuations in concentration (expressed as milliequivalents per litre) of hardness; sulphate, SOT;; chloride, Cr; normal carbonate, COI; bicarbonate, HCO3; in the North Saskatchewan River, 1957.

J I F I mIA1FA1JIJIA IS 1 0 I N ID Fig. 7. Fluctuations in concentration (expressed as milliequivalents per litre) of hardness; sulphate, S01; normal carbonates, CO3; bicarbonates, HC05; in the South Saskatchewan River, 1957. 14 ranged from 32.1 to 79.2 p.p.m.; magnesium, 6.3 to 23.2 p.p.m. and sodium, 4.0 to 23.2 p.p.m. The upper values in all instances occurred during the period of ice cover. Analyses of bicarbonate, chloride, and sulphate were converted to milliequivalents and the sum of these was taken to represent the total anions for a single sample. The m.e. of the hardness determination was taken to represent the sum of hardness-producing cations (chiefly Ca++ and Mg++ ). The excess of the sum of the m.e. of anions over the m.e. of hardness gives a crude estimate of the combined Na+ and K+ content. In general, but by no means invariably, the excess of anions over cations tended to be highest in winter, thus indicating a higher Na+ and K+ content at this time. This agrees with the sodium and potassium analyses available. Sodium content varies, as is revealed by the date of Thomas (1956): North Saskatchewan, South Saskatchewan, Prince Albert Saskatoon Na+ p.p.m. Na+ p.p.m. Feb. 10, 1951 ...... 18.8 Feb. 22, 1951...... 9.3 Feb. 22...... 23.2 May 22...... 10.0 Mar. 21...... 19.0 April 10 11.5 April 20 ...... 15.0 April 23 ...... 20.5 May 21...... 13.3 May 23 ...... 9.8 June 21 ...... 10.3 June 22...... 10.5 July 20 ...... 4.0 Aug. 22 11.0 Aug. 21 ...... 6.3 Sept. 22...... 13.8 Sept. 21 ...... 6.9 Oct. 15 14.0 Oct. 17 8.3 Oct. 22 14.2 Oct. 22 9.8 Nov. 22...... 22.5 Nov. 21...... 10.8 Dec. 27 ...... 27.5 Dec. 21 ...... 17.5 Jan. 22,1952...... 19.8 Jan. 21,1952...... 20.3 Sulphate Sulphate content in both rivers fluctuated widely (Figures 6 and 7). In the South, the range was from 15 to 163 p.p.m. and in the North, 14 to 158 p.p.m. These ranges are comparable to those reported by Thomas (1956) for Saskatchewan River drainage streams. Hydrological conditions appear to play an important role in the yearly fluctuations of sulphate content in these flowing waters. Sulphate concentration frequently bears an inverse relationship to bicarbonate concentration in lakes (cf. Mann, 1958); that is, when bicarbonate is low sulphate is high and vice versa. This is explicable on the basis that during anaerobic conditions, sulphides are produced from the decay of organic material; with the return of aerobic conditions, sulphides are oxidized to sulphates which then enter into solution. Carbonates in the meanwhile would undergo a series of changes as outlined in the preceding section. However, in both the South and North Saskatchewan Rivers, sulphate concentration increased simultaneously with bicarbonate (Figures 6 and 7), and in the North under conditions of low oxygen concentration. This suggests that organic sources of sulphate are of little importance in the Saskat- chewan River. Sulphate determinations reported by Thomas (1956) for various tributaries in the Saskatchewan drainage system indicated that, in general, sulphate concentration increases in winter. The sulphate maximum coincided with low water conditions of late autumn and winter, periods when headwater runoff is lowest. The headwaters are low in sulphate (cf. Thomas, 1956). Downstream from the headwater regions the soils are rich in sulphate, and it appears likely that the winter increase in sulphate is a reflection of a higher proportion of lowland drainage; or, stated another way,. the reduction of sulphate in spring and summer is due to dilution by precipitation runoff. 15 Table 3.—Representative chemical analyses of North Saskatchewan River water, various stations, 1957 and 1958.

Hardness as - Total Dissolved CaCO3 - CO3 HCO3 Cl SO Solids Solids Station ...... Date p.p.m. p.p.m. pH p.p.m. p.p.m. p.p.m. mg./1. mg./1. 1957 Borden ...... Jan. 25 0 287 7.5 372 23 124 — Prince Albert ...... Feb. 6 0 315 7.3 414 31 139 Borden ...... Mar. 18 0 260 7.5 312 31 101 -- 140 11 106 -- — Borden ...... April 16 0 105 8.0 _. Borden ...... May 18 8 104 8.0 146 5 82 Cecil Ferry ...... June 25 14 103 8.3 133 1 72 — Frenchman Butte ...... July 20 6 104 8.3 147 2 63 — — Borden ...... Aug. 23 12 96 7.9 132 3 104 — — Borden ...... Sept. 18 14 112 7.8 166 T. 67 313 — Borden ...... Oct. 29 2 139 7.6 207 2 107 --- — Prince Albert ...... Nov. 6 6 142 7.9 220 2 94 — — Borden ...... Nov. 28 8 166 7.8 253 7 103 300 Frenchman Butte ...... Dec. 18 0 205 — 260 13 108 309 — 1958 Borden ...... Jan. 2 0 260 7.8 353 14 137 467 — North Battleford ...... Feb. 25 0 200 7.2 240 16 115 -- 418 7.3 240 17 110 — 458 Prince Albert ...... Mar. 25 — 208 __. Borden ...... June 20 4 120 8.2 133 1 385 208 Crutwell ...... Sept. 3 — — — 133 1 — 170 167

T—trace Table 4.—Representative chemical analyses of South Saskatchewan River water, various stations, 1967 and 1968.

Hardness as CaCO3 Total Dissolved COi HCOI C1- SC1,1 Solids Solids Station ...... Date p.p.m. p.p.m. pH p.p.m. p.p.m. p.p.m. mg./1. mg. /1. 1957 Yorath ...... Jan. 17 0 232 8.0 260 9 82 — Saskatoon ...... Jan. 29 16 219 7.7 286 6 89 — — Saskatoon ...... Feb. 15 0 226 7.6 266 5 82 Clarkboro ...... Mar. 18 0 175 7.7 206 6 55 — Yorath ...... April 15 0 106 7.7 132 4 108 — St. Louis ...... May 15 8 127 8.0 166 1 88 — Clarkboro ...... June 7 10 106 8.2 134 1 78 — Yorath ...... July 4 14 104 8.3 133 1 75 — — Fenton ...... Aug. 6 16 120 8.3 153 2 107 — Hague ...... Sept. 4 12 124 8.4 167 T. 162 — Saskatoon ...... Oct. 18 12 119 8.2 173 2 115 280 Yorath ...... Nov. 19 10 165 7.9 213 2 126 264 St. Louis ...... Dec. 13 6 182 8.0 267 7 155 376 — 1958 Clarkboro ...... Jan. 6 10 213 8.0 287 3 163 400 — Clarkboro ...... Feb. 18 — 175 7.7 220 5 82 — 294 St. Louis...... Mar. 25 0 150 7.5 160 5 58 — 278 Yorath ...... May 5 12 120 8.2 140 — 96 374 247 Saskatoon ...... June 20 4 110 8.3 127 1 — 404 229 Empress ...... July 21 8 114 8.4 146 1 — 199 182 Gabriel Ferry ...... July 31 14 124 8.3 147 1 54 309 170 Hague ...... Aug. 27 — — — 173 1 47 305 _ 215 Yorath ...... Aug. 28 — — — 167 T. 48 234 211

T--trace While the absolute amount of sulphate tended to be lower in summer, the concentration relative to the other anions increased (Figure 8). At Borden, sulphate was at a maximum percentage on June 21; whereas, the maximum in p.p.m. occurred on February 15. In the South, the highest p.p.m. occurred October 1, but the highest percentage of sulphate in the anions was on April 1. Sodium percentage was greatest when sulphate was at a maximum percentage, suggesting that throughout the year two types of sulphate may be involved. The summer sulphate seems to be either sodium or potassium (non-hardness causing) and the winter sulphate predominantly hardness causing. This does not invalidate the previous hypothesis but merely suggests that the events surrounding the bicarbonate cycle proceed rapidly and are independent of the events controlling sulphate content.

Cl -

CO3

NA+

F E B.I5 MA R.18 APR. I JUN.2I SEP.I8

NA+ 20

JAN.I7 MA R.I APR.! JUL.I 0 CT. I Fig. 8. Relative ionic composition of North Saskatchewan River water at Borden (above) and South Saskatchewan River water at Saskatoon (below) at different times of the year.

Chloride Chloride in the South Saskatchewan varied from a trace to nine p.p.m. but was usually three or less. In the North, the range was from a trace to 31 p.p.m. The chloride content increased under the ice cover in both rivers. The exact cause of this increase is not known, but appears to be associated more with ice cover than just low water, although these two phenomena are themselves associated. In the North, chloride may be associated with some volatile effluents in wastes originating in Edmonton. High concentrations occurring during winter suggest that the chloride content, like sulphate, is influenced strongly by the volume of headwater runoff. 18 Hardness Hardness, as CaCO3, varied from 133 to 414 p.p.m. in the North and from 93 to 306 p.p.m. in the South. The relationship of hardness to alkalinity has been noted, and the relationships of hardness, alkalinity and sulphate are evident in Figures 6 and 7. It is clear that the increased water hardness in winter is due to the bicarbonates and sulphates of calcium and magnesium. The dilution effect of runoff water on hardness is also illustrated in Figures 6 and 7. Saskatchewan River water is hard

Table 5. Representative dissolved oxygen concentrations (uncorrected for altitude), various stations on the North and South Saskatchewan Rivers.

Water % temperature Station Date c.c./1. saturation °C.

North Saskatchewan 1957 Borden ...... Jan. 25 2.5 25 0.1 Borden ...... Feb. 6 1.7 17 0.7 Prince Albert ...... Feb. 11 1.1 10 0.2 Forks ...... Feb. 12 1.1 10 0.2 Borden ...... Feb. 26 2.0 20 0.2 Prince Albert ...... Mar. 13 3.0 30 0.2 Borden ...... Mar. 28 7.3 74 0.5 Prince Albert ...... April 4 9.1 95 1.5 Borden ...... April 16 8.6 100 5.0 Borden ...... June 5 6.9 107 18.0 Petrofka...... July 11 5.4 92 22.5 Borden ...... Aug. 2 6.2 102 21.0 Borden ...... Aug. 23 5.6 91 20.0 Borden ...... Sept. 18 6.5 87 10.5 Borden ...... Nov. 21 9.5 95 0.2 Prince Albert ...... Dec. 24 7.5 75 0.2 1958 Borden ...... Jan. 2 6.7 67 0.2 Borden ...... Jan. 16 3.0 30 02 Borden ...... Jan. 30 2.1 20 0.0 Prince Albert ...... Feb. 14 2.1 20 0.0 Borden ...... Mar. 25 1.2 12 0.5 South Saskatchewan 1957 Yorath...... Jan. 17 8.2 83 0.2 Clarkboro ...... Jan. 23 9.2 95 1.0 Clarkboro ...... Feb. 4 8.0 81 0.5 Forks ...... Feb. 12 7.7 78 0.2 Clarkboro ...... Feb. 26 7.6 77 0.5 Yorath...... Mar. 8 9.4 96 0.5 Clarkboro ...... Mar. 28 9.0 96 2.0 Saskatoon ...... May 6 7.8 120 17.0 Saskatoon ...... June 19 6.8 110 20.0 Leader ...... July 22 5.9 100 23.0 Clarkboro ...... Aug. 23 6.0 100 21.0 Yorath ...... Oct. 1 7.3 106 15.0 St. Louis ...... Dec. 24 9.2 91 0.0 1958 Clarkboro ...... Jan. 6 9.9 100 0.7 Hague ...... Jan. 21 8.4 84 0.0 Yorath ...... Jan. 29 9.3 93 0.0 St. Louis...... Mar. 25 8. 86 0.7 - 19 water. Thomas (1953) suggested the following water hardness classi- fication: Hardness of 1 to 60 p.p.m. as CaCO3 —soft Hardness of 61 to 120 p.p.m. —medium-hard Hardness of 121 to 180 p.p.m. —hard Hardness greater than 180 —very hard Thus, about half the year, i.e., April through September, the water may be classified as hard and the rest of the year as very hard. Thomas (1956) stated that the headwaters of the Saskatchewan River rise as medium-hard water and quickly increase to hard; and that, in spite of little inflow from tributary streams, the main branches do not gain greatly in hardness as the width of Saskatchewan is crossed. Thomas believed that topography and initial flow quickly determined water quality, which was then more or less maintained across the plains. The data of the present study, however, show that hardness changes by two to three fold between summer and winter. Dissolved Solids Dissolved solids were highest during winter and lowest in late summer. In the North, the observed range was from 158 to 463 p.p.m. (Table 3) and in the South, 128 to 400 p.p.m. (Table 4). Since the cations were not measured individually, there is no satisfactory way of checking the dissolved solids against the sum of the constituent ions. However, it is logical that dissolved solids should be at a maximum when hardness, alkalinity and sulphate are. Dissolved Oxygen Two kinds of fluctuations in dissolved oxygen content were discerned; one related to a yearly cycle of events, and the other to a daily cycle. The yearly fluctuations were revealed by single samples taken at different stations throughout the year ,(Table 5). Dissolved oxygen in the South varied from about 5.5 to 12 c.c./1. (66 to 120 per cent of saturation). Dissolved oxygen in the North varied from 1.2 to about 9 c.c./1. (12 to about 110 per cent of saturation). During the ice-free portion of the year the dissolved oxygen content of both rivers was usually from 75 to 98 per cent of saturation. Some instances of supersaturation were observed, but usually the content was less than saturation. Failure to reach saturation may have been connected with biological processes and is discussed more fully below. In the seasonal pattern, no drastic curtailing of dissolved oxygen was noted during the open-water period. The North Saskatchewan suffered severe oxygen reduction during the winter; with the onset of freeze-up the dissolved oxygen content quickly declined as is shown by these observations made at Prince Albert. On January 2, 1957, the dissolved oxygen was 4.9 c.c./1., and 12 days later it was 1.3 c.c./1. An interesting series was obtained in the winter of 1957-58: Date Dissolved oxygen pH Borden Nov. 21 9.5 c.c./1 7.9 (River 90-95% ice-covered) Nov. 28 9.7 7.8 Jan. 2 6.7 7.8 Jan. 16 3.0 7.4 Jan. 30 2.1 7.3 Feb. 26 1.6 7.3 Mar. 18 1.2 7.3 Prince Albert Nov. 25 10.0 c.c./1. 8.1 (River not quite ice-covered.) Dec. 24 7.4 7.9 Jan. 8 6.2 7.8 Jan. 31 1.6 7.3 Mar. 2 1.4 7.5 20 The data from Borden anticipate the events at Prince Albert, suggesting that the water masses characterized by lowered oxygen content moved downstream from a source outside the sampling area and that oxygen depletion was not the result of local causes. The following series of observations in the winter 1957-58 on the South Saskatchewan at St. Louis are of interest; first, as a contrast to conditions in the North, and second, as an indication of events occurring in the South: Dissolved Oxygen Date c.c./1. pH Nov. 25 10.5 8.2 Dec. 24 9.2 8.3 Jan. 8 9.1 8.0 Jan. 14 7.6 8.1 Jan. 31 8.3 8.1 The water temperature at all observations was one or two tenths of a degree above 0°C. At this temperature water fully saturated could be expected to contain about 10 c.c./1. of dissolved oxygen (corrected for altitude). The above data indicated clearly that a measurable demand was being placed on the oxygen content of the South Saskatchewan River during ice cover. Fluctuations in the J a nu a r y values of the oxygen may have been related to variations in the release of sewage from Saskatoon. •

7.0

_i 6.5

6.0

5.5

5.0

1 00

z 9 5 0

LE 90

085

4 8 M 4 8 N4 8 M 4 8N Fig. 9.—Diurnal variation in concentration and per cent of saturation of dissolved oxygen at three North Saskatchewan River stations. M, midnight; N, noon; mountain daylight saving time. 21 There is no reason to suppose that 7.6 c.c./1. (about 75 per cent of saturation) was the minimum value attained. Oxygen depletion under the ice may be the result of several factors, among which are: (1) hindrance of the ice cover to absorption of atmos- pheric oxygen by the water, (2) prevention of escape of gases from decomposition, (3) little photosynthetic activity by plants. Superimposed upon the yearly pattern of dissolved oxygen content are small daily cycles. The smaller cycles, like the larger, are influenced by temperature of air and water, hydrological, and meteorological events. Brief showers of rain increased the concentration of dissolved oxygen in the surface waters of the rivers on different occasions, but the changes were of small magnitude and of short duration. However, biological phenomena play a considerable role in the daily changes in dissolved oxygen content. Twenty-one dissolved oxygen determinations were made in 24 hours in the South Saskatchewan River at Empress (Table 6). The station was established in slowly flowing water about one foot deep and downstream from a dense growth of small submerged plants rooted in the river bottom. At 7:30 p m. July 21, the dissolved oxygen was 6.1 c.c./1. (11 a saturation); by 11.30 p.m. the concentration was 4.7 c.c./1. (82% saturation). At 6:15 a.m. July 22, the dissolved oxygen was 4.3 c.c.- /1. and then increased throughout the day to reach a maximum (6.6 c.c./1. at 6:00 p.m. This series of observations indicated that during the hours of daylight, photosynthesis by the plants produced a substantial amount of oxygen, enough to supersaturate the water from 11:00 a.m. to the final observation at 7:00 p.m. The difference between the minimum and maximum concentrations observed was 2.3 c.c./1. During the hours of darkness, oxygen demands within the river reduced the dissolved oxygen below saturation; or, in other words, the demand ex- ceeded the rate at which oxygen entered the water from the atmosphere.

Table 6.-Diurnal variation in dissolved oxygen content of the South Sask- atchewan River at Empress ferry, Saskatchewan, July 21-22, 1958.

Time Dissolved Oxygen Temperature °C. (Mountain Daylight Per cent of Saving) Observed Corrected* Saturation c.c./1. c.c./1. Water Air July 21, 7.30 p.m. 6.1 6.47 117.0 26.5 26.5 8.30 6.0 6.36 114.0 25.8 23.8 9.30 5.4 5.72 101.0 25.0 19.0 10.30 5.0 5.30 93.0 24.0 18.6 11.30 4.7 4.98 86.5 23.8 18.6 July 22, 4.00 a.m. 4.9 5.19 86.0 21.5 13.5 5.30 4.5 4.77 78.5 21.1 13.9 6.15 4.3 4.56 75.5 21.5 14.6 7.00 5.0 5.30 88.0 21.5 16.6 8.00 4.9 5.19 86.0 21.7 20.7 9.00 5.4 5.72 95.5 22.0 22.3 10.00 5.4 5.72 97.0 22.8 22.3 11.00 5.7 6.04 105.0 23.6 24.0 12.00 5.7 6.04 105.0 23.5 25.0 1.00 p.m. 5.9 6.25 111.0 25.2 25.6 2.00 6.2 6.57 119.0 26.0 25.0 3.00 6.2 6.57 120.0 26.4 26.2 4.00 6.2 6.57 121.0 26.9 28.0 5.00 6.3 6.68 122.0 26.7 28.0 6.00 6.6 7.00 126.0 26.3 27.0 7.00 5.7 6.04 107.0 25.5 26.6

*Corrected for altitude. 22 Table 7.-Chemical observations on tributaries of the North Saskatchewan River.

Hardness as - Temp. 02 p.p.m. CO3 HCM C1. Sal Dissolved Station Date °C. pH c.c. /1. CaCO3 p.p.m. p.p.m. p.p.m. p.p.m. solids, mg./1.

Shell River 1957 Highway 55 May 14 - 8.0 - 360 12 223 5 147 - Nov. 5 1.5 - 12.0 447 0 250 1 208 553 Dec. 10 0.3 7.2 6.5 653 0 315 4 276 673 1958 Feb. 14 0.1 7.2 6.2 427 0 284 2 178 560 Mar. 25 1.5 - 7.0 380 - - 4 182 604 May 8 12.0 8.2 6.5 366 - - - - 564 Sept. 5 12.7 7.8 5.4 420 - - 2 126 501 Battle River 1957 Highway 40 May 2 15.0 8.3 4.5 146 14 152 3 99 - Sept. 18 - 7.9 - 233 32 278 9 184 - 1958 Feb. 25 0.8 7.2 0.6 367 0 460 20 144 711 1957 Deer Creek Nov. 27 0.3 7.5 10.0 420 0 375 5 91 543 Little Red River Dec. 11 0.2 7.2 8.5 327 0 360 2 150 481 1958 Little Red River Feb. 14 0.2 7.2 8.0 433 0 366 2 70 560 Deer Creek ...... Aug. 19 18.0 8.6 5.1 320 20 284 2 43 375 At 4:00 p.m. on July 22, the oxygen content at the station was 6.2 c.c./1. The content near the centre of the river was 5.4 c.c./1. indicating that the cycle of events as described for the station downstream from the plant bed was not representative of the whole river. Similar series of observations were made at four stations on the North, six on the South, and three -below the confluence of the two branches. The results of some of thes series are shown in Figures 9 and 10. The observations were spread over the entire summer and, no doubt, seasonal changes influenced the daily cycles. Hours of light intensity suitable for photosynthesis would I* expected to decrease with the decreasing number of daylight hours". It would also be expected that oxygen concentration would decrease "during the hours of darkness and commence to increase with resumpticil of photosynthetic activity after daybreak. From Figures 8 and 9 it may be seen that the oxygen concentration frequently continued to decrease through the morning hours and that the minimum occurred about ten o'clock. This mid-morning minimum agrees with data given by Odum (1956). The factors responsible for the mid-morning minimum are not known. Physical and chemical factors of the environment and perhaps inherent qualities of the organisms (cf. Doty and Oguri, 1957) may be responsible. Maximum oxygen

6 . 5

5 5

5.0

100

9 0

9 4 8 5

1 1 1 1 1 1 1 1 1 1 1 4 8 N 4 8 N 4 8 M 4 8 Fig. 10.—Diurnal variation in concentration and per cent of saturation of dissolved oxygen at two stations on the South Saskatchewan River; Saskatchewan Landing, open circles and Clarkboro, closed circles; and at Nipawin, Saskatchewan River. M, Midnight; N, noon; mountain daylight saving time. 24 concentration usually occurred in late afternoon. The failure of dissolved oxygen to reach saturation at several stations suggests the action of biotic factors. Tributary Waters The chemical composition of the tributary waters (Table 7) was, in general, similar to that of the 1North Saskatchewan on comparable dates. With the exception of the Battle River, the tributaries tended to have slightly harder water. It is interesting to note that the side streams showed an increase in bicarbonatq and hardness in conjunction with a shift to a lower pH under ice conditons, as did both the North and South

Saskttchewan Rivers. 4 No flow was perceptible in tht Battle River when the observation of February 25, 1958, was made. In winter the flow of the other streams was quite low but readily apparent. The volume of flow of the side streams is not great when compared to that of the North Saskatchewan; thus, no appreciable relief of severe oxygen depletion in the main river can be expected from the tributaries.

Biological Factors Plankton Measured volumes (usually 50 1.) were taken from the river surface and poured through a net of silk bolting cloth with 173 meshes per linear inch. A Palmer chamber was used in enumeration of the phytoplankton. In general, the number of diatoms was low (Table 8) and the numbegof green algae much higher. The series of samples was not large; however, the results agree rather well with a similar series of samples from the Yellowstone and Missouri River (Damann, 1951). Most of the diatoms were probably cells which had broken away from encrusting mats on the stones in the riffle areas of the river bed. The green algae were predominantly small, single-celled forms. The samples were counted; then dried,

Table 8.-Plankton organisms per litre of surface water at various stations on the Saskatchewan River system, 1958.

Green Station Date Diatoms Algae Other

Hague June 24 1,680 1,080,000 1 copepod Fenton July 9 19,200 558,000 6,000 blue-green algae 720 rotifers Weldon July 10 300 360,000 Saskatoon July 18 2,940 1,200,000 8,000 blue-green algae Empress July 22 1,200 60,000 Sask. Landing July 24 3,000 300,000 St. Louis July 29 7,800 600,000 Gabriel Ferry Aug. 1 2,640 660,000 7,500 blue-green algae Hague Aug. 25 3,000 600,000 7,000 blue-green algae Clarkboro ...... Aug. 27 2,500 360,000 10,000 blue-green algae Yorath Island Aug. 28 2,880 120,000 Frenchman Butte Aug. 19 1,440 720,000 . Crutwell ...... Sept. 2 14,760 300,000 3,000 blue-green algae Cecil Sept. 4 4,740 540,000 . Borden Sept. 9 4,200 420,000 Nipawin ...... Aug. 5 1,260 1,090,000 5,000 blue-green algae D.N.R. Boathouse Aug. 9 1,360 780,000 Fort a la Come Aug. 12 900 420,000 6,000 blue-green algae

25 weighed, and ashed to obtain the dry weight of the plankton and the percentage of mineral matter. In addition to the plankters, the net also retained considerable quantities of suspended silt which was evident both in counting and from the high percentage of mineral matter (Table 9). Damann (1951) presented a table of the probable significance of numbers of plankton occurring in waters of the Missouri River Basin. A portion of the table follows:

Total Plankton, cells per litre Probable significance. 0-100,000 Little or no productivity. Taste and odour problems unlikely. 100,000-500,000 Low productivity water, potentially productive depending on environment and season. 500,000-1,000,000 Unpredictable water. Odour problems could develop at any time. 1,000,000-5,000,000 Odour problems are very likely to occur with the presence of specific organisms.

It would be presumptuous to attempt to draw conclusions from a series of samples as small as that given in Table 8. However, it may be noted that areas near sources of organic pollution tended to have higher numbers of algae. The Yorath Island station above Saskatoon received water which was virtually unaffected by domestic sewage for 200-300 miles and had the lowest observed crop of plankton. Samples from Clarkboro and Hague taken at comparable dates had from three to five times as much phytoplankton. These stations are enriched by the discharge of domestic sewage from Saskatoon.

Coliform Bacteria Bacterial populations were sampled by passing a measured volume of water through a micro-filter which retained the bacteria upon its surface. The filter with the bacteria adhering was placed in a plastic petri dish containing a pad saturated with a nutrient broth and incubated at 37° C. for 18-24 hours. At the end of this period, colonies resulting from the growth of individual bacterial cells on the filter were visible. The nutrient medium favoured the growth of coliform bacteria and retarded the growth of other types. Coliform bacteria are not pathogenic; some species normally live in the intestinal tracts of vertebrates including man. Therefore the presence of these bacteria in the water suggests the possibility of fecal contamination. No clear pattern of occurrence of coliforms in the North Saskatchewan was evident. The highest number of typical colonies, 400 per 100 ml. was recorded at Frenchman Butte, June 11, 1957. Frequently no coliforms were found in samples of North Saskatchewan water. The failure to detect coliforms was particularly noticeable during the winter when the river was ice covered. Possibly some of the chemical wastes in the river may have a bactericidal action. At Yorath Island, upstream from Saskatoon, samples yielded low numbers of bacteria. Stations downstream from Saskatoon usually had considerable numbers of coliform bacteria in the water; the highest recorded was 15,000 coliforms per 100 ml at Clarkboro on October 29, 1957. 26 Table IL-Standing crop of plankton and mineral matter in 50-litre samples from different stations, Saskatchewan River system, 1958.

Station Date Dry Weight, mg. Ash, percentage

Hague ...... June 24 48.0 77.9 Fenton ...... July 9 558.2 96.0 Weldon ...... July 10 84.7 89.5 Saskatoon ...... July 18 584.5 93.0 Empress ...... July 22 9.0 81.0 Saskatchewan Landing ...... July 24 49.2 85.4 St. Louis ...... July 29 112.1 89.0 Gabriel Ferry ...... Aug. 1 40.3 81.0 Nipawin ...... Aug. 5 154.7 85.0 D. N. R. Boathouse ...... Aug. 9 86.9 82.5 Fort a la Come...... Aug. 12 90.3 91.0 Frenchman Butte ...... Aug. 19 17.8 77.0 Hague ...... Aug. 25 10.7 51.3 Clarkboro ...... Aug. 27 26.0 85.8 Yorath Island ...... Aug. 29 7.4 69.0 Crutwell ...... Sept. 2 27.7 86.4 Cecil ...... Sept. 4 8.5 56.5 Borden ...... Sept. 9 9.6 57.6

Bottom Fauna The animals living on and in the river bottom were sampled with an Ekman dredge and a Surber sampler. By means of the dredge, a sample one-forty-fifth of a square metre in extent could be removed from the river bed. The dredgings were washed through a series of three screens, the finest of which had 28 meshes per inch. Animals contained in the dredgings were picked from the screens and preserved for weighing and counting in the laboratory. The Surber sampler was used in shallow water where the substrate was too hard or rocky to be sampled with the dredge. A Surber sampler consists of a frame enclosing one square foot and fitted with a bag of fine mesh material. In use, the sampler is held firmly against the river bed, and the gravel or stones enclosed by the frame are vigor- ously stirred. Insects and other organisms dislodged from the bottom are swept by the current into the bag of the sampler from which they may be removed and preserved. Sampling of the bottom fauna indicated: (1) the bottom fauna of the Saskatchewan River is quite unevenly distributed, (2) mayflies, caddis flies, and stoneflies are associated with the stony and gravelly bottoms of rapidly flowing riffles, (3) oligochaetes and chironomids are associated with muddy bottoms, and (4) the sand bottom areas are extremely unproductive of bottom fauna. The heaviest concentration of bottom fauna encountered was in a protected area of the North Saskatchewan at Frenchman Butte on July 19, 1957. A dredging of soft mud, which had a strong odor of organic decomposition, contained 450 oligochaetes and 113 chironomids. These animals had a wet weight of 4.58 grams which represents a dry weight of 275 lbs./ac. This concentration is not typical of the river, but does serve to point up the very uneven distribution of the bottom dwelling forms. In the hard sand bottom, a few feet away from the protected area in which the dense population of oligochaetes and small chironomids occurred, it was possible to take several dredgings without finding any 27 Table 10.—Summary of bottom fauna analysis of the Saskatchewan River, 1957.

Av. No. Av. wet Per cent representation all weight organ- less Av. dry weight No. of Chiron- May- Caddis- Oligo- Miscel- isms Molluse Samples omids flies flies chaetes laneous sq. m. shells kg./ha. lb./ac.

North Saskatchewan River . —Ekman dredge ...... 14 46 — — 51 3 5,220 21.330 32.0 28 . 48 —Surber sampler ...... 4 6 89 — — 5 570 4.078 6.12 5.45 South Saskatchewan River —Ekman dredge ...... 15 82 — — 10 8 495 1.800 2.70 2.40 —Surber sampler ...... 3 5 42 46 — 7 463 4.057 6.09 5.42

Table 11.—Summary of bottom fauna analysis of the Saskatchewan River, 1958.

North Saskatchewan River —Ekman dredge...... 18 58 — — — 41 540 1.260 1.89 1.68 —Surber sampler ...... 8 4 64 31 ± — 129 1.442 2.02 1.80 South Saskatchewan River —Ekman dredge ...... 35 74 -- — 23 3 810 2.340 3.51 3.12 —Surber sampler ...... 17 + 73 25 — 1 515 3.788 5.68 5.09 Saskatchewan River —Surber sampler ...... 7 + 36 63 — + 387 4.734 7.10 6.32 macroscopic bottom forms. Rock and gravel bars were the most produc- five sites for bottom fauna in the river. Muddy areas in backwaters and other protected localities were second in importance as producers of bottom fauna. A substrate of mixed sand and mud was third in producing bottom fauna, and an all-sand bottom was the least productive. The uneven distribution of the bottom fauna has made it desirable to summarize separately and by years the results of the two types of sampling (Table 10 and 11). Here again is emphasized the caddis fly- mayfly and chironomid-oligochaete division of the bottom fauna. A few rich dredgings in the North Saskatchewan in 1957 have had a dispro- portionate effect on the values for that year (Table 10). These dredgings have not been used in calculating the following standing crop figures, which are based on all the other samples taken. Ekman dredge samples in the North Saskatchewan River averaged 1.9 kg. per ha. (1.7 lb. per ac. ) dry weight. Corresponding figures for the South Saskatchewan River were 3.3 kg. per ha. (2.9 lb. per ac. ). Surber samples averaged 3.4 kg. per ha. (3.0 lb. per ac. ) dry weight in the North Saskatchewan. Averages for the South Saskatchewan were 5.7 kg. per ha. ( 5.1 lb. per ac. ) dry weight. The quantity of the standing crop of bottom fauna in the two rivers is compared with that of several Saskatchewan lakes (Table 12). The standing crop of bottom fauna in the Saskatchewan River as a whole appears to correspond in quantity to those lakes which have the lowest standing crop. It should be borne in mind that standing crop is a measure of the amount on hand at the moment of sampling, and does not reveal how rapidly the crop is being produced or removed. Fish Fauna Twenty-four species of fish were taken either in gill nets or by seining; one species not taken by the survey was reported by domestic gill net licensees. Nomenclature used here follows Scott (1958). Species taken by gill netting included: Lake Sturgeon, Acipenser fulvescens Rafinesque. One sturgeon was netted in the South Saskatchewan River at Fenton and three were taken

Table 12.-The average standing crop of bottom fauna in the North and South Saskatchewan Rivers and in certain Saskatchewan lakes.

No. of Station samples kg. /ha. lb./ac.

North Sask. River-Ekman dredge ...... 18 1.9 1.7 South Sask. River-Elcman dredge ...... 50 3.3 2.9 North Sask. River-Surber sampler ...... 12 3.4 3.0 South Sask. River-Surber sampler ...... 20 5.7 5.1 Sask. River-Surber sampler ...... 7 7.1 6.3 Cree Lake' ...... 193 1.6 1.4 Reindeer Lake' ...... 65 1.6 1.4 Lac la Plonge2 ...... 145 2.8 2.5 Cumberland Lake3 ...... 62 5.3 4.7 Wollaston Lake' ...... 120 4.7 4.2 Frobisher Lake4 ...... 24 2.2 2.0 Ile a la Crosse ...... 200 9.0 8.0 Namew Lake'...... 32 16.8 14.1 Big Peter Pond Lake 4 ...... 87 73.4 65.3

'Rawson 1959, 'Ruggles 1959, 'Reed 1959, 4Rawson 1957a 29 from the Saskatchewan, two at Codette and one at Fort a la Come. Three were caught in a fish trap placed in the Old Channel above Cumberland Lake. One sturgeon was observed surfacing at the forks of the North and South branches of the Saskatchewan. Considerable numbers of sturgeon were reported to occur in the South Saskatchewan in the vicinity of its junction with the Red Deer River. A ferryman at Maymont reported that 20 to 30 years ago sturgeon were frequently seen in the North Saskatche- wan in that area, but that none had been seen in recent years. Lake Whitefish, Coregonus clupeaformis (Mitchill ). The survey parties captured no whitefish, but reports from several gill net licensees in 1958 mentioned whitefish. All were taken in October and November in the Saskatchewan between Fort a la Come and Nipawin; apparently a few whitefish move into the river when it is low and clear in the autumn. Northern Pike, Esox lucius Linnaeus. Pike were in all localities. Goldeye, Amphiodon alosoides Rafinesque. Distributed throughout the Saskatchewan and its branches in the province. Mooneye, Hiodon tergisus LeSueur. One specimen was caught in the fish trap set in the Old Channel near Cumberland Lake. Quillback Sucker, Carpiodes cyprinus (LeSueur ). Quillbacks were most frequently taken in the South Saskatchewan in quiet water over a bottom rich in organic muck. Only one quillback was taken from the Saskatchewan, and two were caught in the North Saskatchewan. Northern Redhorse, Moxostoma aureolum (LeSueur ). Widely distributed in all three rivers. Silver Redhorse, Moxostoma anisurum (Rafinesque ). No silver redhorses were taken from the North Saskatchewan and only one from the Saskatchewan at Codette. Three were netted at the mouth of Swift Current Creek, and two were seined from the South Saskatchewan below Saskatoon. White or Common Sucker, Catostomus commersoni (Lacepede ). Common suckers appear to be more numerous in the North Saskatchewan and its tributaries than in the South Saskatchewan. Longnose Sucker, Catostomus catostomus (Forster). Widely distributed in all three rivers. Flathead Chub, Platygobio gracilis (Richardson). Rarely taken in gill nets, one was caught at Fort a la Come and two at Clarkboro. Burbot, Lota iota (Linnaeus). Rather infrequently netted, but probably well distributed through the rivers, particularly the South Sask- atchewan. Walleye, Stizostedion vitreum (Mitchill ). Walleyes were netted only at Frenchman Butte and Deer Creek on the North Saskatchewan. Walleyes seem to be well distributed in the South and Saskatchewan Rivers. Sauger, Stizostedion canadense (Smith). Sauger appear to be most numerous in the Saskatchewan and in the South below Saskatoon. Eleven smaller species taken by seining included: Mountain Sucker, Pantosteus jordani Evermann. About 60 specimens were taken from Swift Current Creek a few miles above its confluence with the South Saskatchewan. Pearl Dace, Margariscus margarita Cope. Collected only in Swift Current Creek. 30 Lake Chub, Couesius plumbeus (Agassiz ). Thirteen specimens were seined from a small creek, tributary to the South Saskatchewan. between the towns of Cabri and Shackleton. Longnose Dace, Rhinichthys cataractae (Valenciennes). Collected in swift water in five localities: Swift Current Creek, Estuary, Birson, Cecil, and Nipawin. Emerald Shiner, Notropis atherinoides Rafinesque. Widely distributed in the South Saskatchewan and the Saskatchewan Rivers, but not taken in any seine hauls made in the North Saskatchewan River. River Shiner, Notropis blennius (Girard). Collected in the South Saskatchewan at Estuary, Leader, Saskatoon, Weldon, and Fenton, and in the Saskatchewan below Nipawin. Not present in seine hauls made in the North Saskatchewan River. Fathead Minnow, Pimephales promelas Rafinesque. Collected in a tributary of the South Saskatchewan between Cabri and Shackleton and in Swift Current Creek. Collected in two tributaries of the North Sask- atchewan, Deer Creek and Shell River, and in the North Saskatchewan at Frenchman Butte. Brook Stickleback, Eucalia inconstans (Kirtland). Not collected in the big rivers but taken from two tributaries of the North Saskatchewan, Little Red River and Deer Creek, and from a tributary of the South Sask- atchewan between Cabri and Shackleton. Troutperch, Percopsis omiscomaycus (Walbaum). Collected at Saska- toon and at Fort a la Come. Yellow Perch, Perca flavescens (Mitchill ). One specimen was seined at Fort a la Come and one at Estuary. Spoonhead Muddler, Cottus ricei Nelson. A few sculpins were collected near Nipawin. In addition to the small species, fry and young individuals of large species were taken by seining. Interestingly the flathead chub, which was found in considerable numbers wherever seine hauls were made in the South Saskatchewan and Saskatchewan Rivers, was collected only at Cecil on the North Saskatchewan. At this station five individuals were taken in four hauls. Also of interest is the fact that no shiners were collected in the North Saskatchewan, although they were abundant in other localities seined. No sauger, sturgeon or silver redhorse suckers were taken from the North Saskatchewan.

Fish Populations and Utilization Fish populations were sampled by means of nylon gill nets of 2-, 3-, 4-, and 5-inch stretched mesh. Nets were 10 or 25 yards in length. The average number of fish caught per set indicated that 10-yard nets were about as efficient as 25-yard nets in capturing fish. The South, the North, and the Saskatchewan, because of their swiftly flowing waters and lack of extensive areas of backwater, are not amenable to gill-net fishing. Nets set parallel with the current in rapidly flowing water probably do not fish effectively. Nets set across currents are pushed nearly flat by the force of the water against the corks, with the result that this type of set is ineffectual. An effective method at times is to fasten a short piece of net, up to 25 feet, to a long pole, which is then pushed out from shore into the river. Gill-net sets made during 1957 and 1958 included six sets in tributaries; one in Swift Current Creek, three in the Battle River, and one each in Deer Creek and Little Red River. All sets were made immediately above the confluence of the tributary and the main river. There were no 31 visible barriers which kept the fish in the tributary permanently isolated from the adjacent river; therefore, in further analyses the tributary catches are considered as part of the adjacent river catch. Numerically, goldeyes dominated the catches of all three rivers (Table 13). More than half the catch in the North Saskatchewan was goldeyes; longnose suckers and northern redhorse suckers were second and third, followed by common suckers. One third of the South Saskatchewan catch was goldeyes with northern redhorse suckers and longnose suckers second and third, followed by quillback suckers. The large number of quillbacks was not typical of the river as a whole; nearly all were taken below the dam at Saskatoon. In the Saskatchewan, goldeyes made up 40 per cent of the numbers with

Table 13.-Numerical composition of the total catch of gill nets set in the North Saskatchewan, South Saskatchewan and Saskatchewan Rivers, 1967 and 1958.

North Saskatchewan South Saskatchewan Saskatchewan 30 sets 48 sets 18 sets Species Number Per cent Number Per cent Number Per cent

Goldeye ...... 93 51.4 80 33.1 18 40.0 Northern Redhorse ...... 20 11.0 49 20.3 3 6.7 Longnose Sucker ...... 26 14.4 34 14.1 1 2.2 Pike ...... 10 5.5 7 2.9 2 4.4 Walleye ...... 12 6.6 6 2.5 k 13.4 Sauger ...... 0 0.0 7 2.9 8 17.8 Silver Redhorse ...... o 0.0 3 1.2 1 2.2 Common Sucker...... 17 9.4 12 5.0 _1 2.2 Chub ...... o 0.0 4 1.6 1 2.2 Burbot ...... 1 .5 7 2.9 0 0.0 Sturgeon ...... if 0.11 1 .3 3 6.7 Quillback Sucker ...... 2 1.2 32 13.2 1 2.2 Total ...... 181 100 242 100 45 100 sauger and walleyes second and third. The same species dominated the catch on a weight basis (Table 14) but in slightly different order. In the North Saskatchewan, the order of importance was goldeyes, northern redhorse, and longnose suckers. In the South Saskatchewan the order was longnose suckers, quillback, goldeyes, and northern redhorse. Gold- eyes were first in the Saskatchewan followed by walleyes and sauger. The catch of the two-inch mesh nets accounted for 1.7 per cent of the numbers and 0.5 per cent of the weight of the total catch of fish taken by gill netting; the five-inch mesh nets accounted for 3.2 per cent of the total number and 3.0 per cent of the total weight of fish captured. The catch of the two- and five-inch mesh is, therefore, insignificant both in numbers and in weight. The combined three-inch mesh catch was 285 fish which weighed 353 lbs.; whereas, that of the four-inch mesh was 160 fish which weighed 350 lbs. By weight, non-game fish comprised 62 per cent of the four-inch mesh catch in the South Saskatchewan and 68 per cent in the North. Sixty-four per cent of the three-inch catch in the South was rough fish, but only 40 per cent of the catch in the North was suckers and other rough fish. The river catches are compared with test net results from selected Saskatchewan lakes (Table 15). The two-inch mesh catch was lower in numbers for the South and the Saskatchewan Rivers than for any lake given. The catch of the three-inch mesh in both the North and the South Saskatchewan Rivers is similar in numbers to the catches from Lac la Plonge, Reindeer, Wakaw, and Sturgeon Lakes. The average weight per 32 Table 14.-Weight composition of the total catch of gill nets set in the North Saskatchewan, South Saskatchewan, and Saskatchewan Rivers, 1957 and 1958.

North Saskatchewan South Saskatchewan Saskatchewan 30 sets 48 sets 18 sets Species Pounds Per cent Pounds Per cent Pounds Per cent

Goldeye ...... 86.3 28.2 68.4 19.1 13.9 21.4 Northern Redhorse ...... 75.8 24.8 42.0 11.7 4.4 6.8 Longnose Sucker.. . .. 52.7 17.2 75.5 21.1 2.8 4.3 Pike ...... 29.0 9.4 25.1 7.0 6.4 9.8 Walleye ...... 26.2 8.6 21.5 6.0 16.2 24.9 Sauger ...... 0.0 0.0 10.3 2.9 8.3 12.8 Silver Redhorse ...... 0.0 0.0 12.2 3.4 3.9 6.0 Common Sucker ...... 28.3 9.3 16.7 4.7 2.9 4.5 Chub ...... 0.0 0.0 1.9 .5 .5 .8 Burbot ...... 1.3 .4 8.0 2.2 0.0 0.0 Sturgeon ...... 0.0 0.0 5.0 1.4 1.2 1.8 Quillback Sucker ...... 6.3 2.1 71.1 19.9 4.5 6.9 Total ...... 305.9 100.0 357.7 99.9 65.0 100.0

fish was greater in all three rivers than in Cumberland Lake. The catch of the four-inch mesh in the North and the South Saskatchewan Rivers was nearly as large as that in the less productive lakes in Saskatchewan. Utilization of the fish populations in the rivers is accomplished through angling and domestic gill-net fishing. Angling pressure is unevenly distributed, being greatest near Saskatoon, Prince Albert, the forks of the North and the South, Fort a la Come, Nipa win, Leader, and Estuary. Some angling is done near all of the ferry crossings and bridges. It is not uncommon to count 200-250 anglers in the first mile or two of river below the dam at Saskatoon on a summer weekend. La Cole Falls near Prince Albert is probably the second most-used angling location on the rivers. Goldeye and pike are the most desired species; however, many anglers using heavily weighted lines fish for suckers and burbot on the river bottom. The amount of fish harvested by anglers is not known and is difficult to estimate. In the area immediately adjacent to Saskatoon, an average of 20 anglers per day catching four pounds of fish each would in 100 angling days remove, 8,000 pounds of fish. This is probably a low estimate and the harvest could be twice or three times this amount. The domestic gill-net fishery is centred in the Fort a la Corne-Nipawin area with licenses scattered in other localities. In 1957 and 1958 licensees were provided with forms on which to record gill net catches. About 40 per cent responded in 1957 and 38.5 per cent in 1958 (Table 16). Each year some persons bought licenses but did not fish. Some license holders merely summarized catches for the season, but several reported the catch of each set separately. If the returns are representative in both years, the total catch for all licenses issued would be about 5,000 fish in 1957 and 5,600 in 1958. It is worth noting that for returns reported on a daily basis, the catch of game fish did not exceed the limit placed on anglers. The license returns and the observations of the survey parties refute the contention of some anglers that gill net operations are removing a disproportionately large number of fish, and that gill-net fishing constitutes a threat to angling. Sturgeon are taken commercially from the Saskatchewan and Torch Rivers by the residents of Cumberland House. This fishery has had an annual harvest of about 7,000 pounds for the past 12 years. In late summer 33 Table 15.-Average catch of fish in numbers and weight per 50 yards of gill net of four sizes of mesh for the North Saskatchewan, South Saskatchewan and Saskatchewan Rivers with comparative data from Saskatchewan lakes.

2-inch 3-inch 4-inch 5-inch No. of sets Number Pounds Number Pounds Number Pounds Number Pounds

North Saskatchewan River...... 30 - - 16.6 20.5 11.0 28.4 1.3 2.9 South Saskatchewan River ...... 48 3.3 1.4 13.5 17.0 14.5 26.9 1.5 1.6 Saskatchewan River ...... 18 6.0 3.4 9.6 10.9 4.6 15.2 3.2 4.6 Canoe Lake' ...... 2 ...... 6 17.8 24.2 33.8 67.3 37.2 86.5 6.8 20.0 Lac la Plonge 2 ...... 35 12.7 17.0 11.6 21.4 12.9 Reindeer 33.0 5.3 20.0 Lake 3 ...... 44 16.2 17.8 15.0 27.0 13.0 31.6 4.6 14.2 Cumberland Lake3 ...... 10 85.7 44.4 57.2 50.4 25.9 53.4 11.1 34.2 Namew Lake 6 69.7 31.6 30.8 41.4 22.0 40.2 10.8 35.2 Wakaw Lake' ...... 5 17.0 - 5.6 - 2.4 - 1.6 - Sturgeon Lake' ...... 6 14.2 - 17.8 - 9.7 - 1.7 - Montreal Lake'4 ...... 2 96.0 - 56.0 - 60.0 - 15.0 - Bigstone Lake 5 ...... 6 29.8 - 27.2 - 18.5 - 4.5 - Last Mountain Lake 59 29.2 16.5 43.1 35.2 22.2 45.4 8.3 27.2

2 3 5 'Ruggles, 1959; Novakowski, 1955; Reed, 1959; *Mendis, 1956; Atton and Murray, 1952. Table 18.—Summary of domestic gill-net catches in the North and South Saskatchewan Rivers in 1857 and 1858.

1957 1958 Number of licensees contacted ...... 140 189 Non-fishing ...... 22 34 Returns summarized as catch reports ...... 10 4 Returns of catch reported on daily basis...... 25 35 Total returns ...... 57 73 Calculated number of fishing days...... 175 131 Number of fish taken on all licenses goldeye ...... 719 (35.5%) 833 (37.5%) walleye and sauger ...... 494 (24.5%) 319 (14.6%) pike ...... 283 (14.2%) 389 (17.8%) suckers, etc ...... 518 (25.0%) 630 (29.0%) TOTAL ALL FISH ...... 2014 2169 Average number of fish per license (all licenses) goldeye ...... 20.5 23.8 walleye and sauger ...... 14.1 9.1 pike ...... 8.1 11.1 TOTAL GAME FISH ...... 42.7 44.0 Average number per license (reported on daily basis) goldeye ...... 25.4 23.6 walleye and sauger ...... 17.0 8.0 pike ...... 6.7 9.4 TOTAL GAME FISH ...... 49.1 41.0 Average number of fish per fishing day goldeye ...... 3.6 4.7 walleye and sauger ...... 2.4 1.6 pike ...... 0.96 1.9 TOTAL GAME FISH ...... 7.0 7.2 Estimated total catch of all licenses issued goldeye ...... 1780 2150 walleye and sauger ...... 1190 830 pike ...... 700 1000 TOTAL GAME FISH ...... 3670 3983 TOTAL ROUGH FISH ...... 1300 1650 TOTAL ANNUAL CATCH ...... 4970 5633 of 1958, 29,000 pounds of goldeyes were netted by commercial fishermen from Cumberland House; most of the catch was taken in the Old Channel and the remainder in Cumberland Lake. The last commercial catch of goldeyes, prior to 1958, was 10,000 pounds taken in 1943. To obtain information concerning downstream movements of fish, a trap was placed in the Old Channel of the Saskatchewan about eight miles upstream from Pemmican Portage at Cumberland Lake, in August, 1958. For the first few days no goldeyes were taken; during this time commercial fishermen operating a few miles upstream were making catches up to 600 pounds per night. One calm evening just at dusk the surface of the river suddenly became literally dimpled with feeding goldeyes. Apparently the first wave of downstream migrants had reached the fish trap. Unseason- ably high water, carrying much debris, forced the removal of the trap before the main body of goldeyes reached the area, but not before about 250 goldeyes had been tagged and released to continue downstream. Seven tags were recovered in The Pas area within a few weeks. One goldeye travelled about 110 miles in the four-day interval between tagging and recapture. 35 Fish Growth Examination of the length, weight, and age data of goldeyes caught in the North and the South Saskatchewan Rivers indicated that all could have been drawn from one population. Therefore, the data from 170 fish were pooled, resulting in the following values: Age in years Average fork length Average weight inches ounces 1 6.0 1.0 2 7.5 2.5 3 10.6 8.0 4 11.5 9.8 5 11.8 11.0 6 13.1 15.8 7 13.5 17.5 8 13.8 18.3 9 14.6 22.2 10 15.2 24.5 Considerable overlap in the ranges of weight and fork length of the year classes occurred from the age of three onward. In comparing the age-length and age-weight data from the Saskatche- wan River goldeyes with similar data from goldeyes caught in Cumber- land Lake, it was found that the river fish are, in general, longer and

25 _ I 4

I 3

I 2

4 7 w X

5 6

0/ 5

2 3 4 5 6 7 8 9 10 AGE, YEARS

Fig. 11.—Age-weight and age-length relationships of river-caught goldeye (solid dots) and Cumberland Lake goldeye (open circles). 36 seining wasdoneatseveral locationsandgoldeyefryweretakeninall South SaskatchewanRiver inthevicinityofAlberta-Saskatchewan boundary thantheywerein ThePas-CedarLakearea.Duringthissurvey noted thatgoldeyefrywere muchmorereadilyobtainedbyseininginthe atchewan Riverscombined withlowavailabilityoffryinthelower areas. Thehighavailability offryintheupperSouthandNorthSask- about 65mm.inlengthshowednoannuli. Saskatchewan areaspawninJune.Ifthespawningtemperature recorded of Sprules(1949a).Hereportedthatgoldeyeeggsfloatonthewater every locationatwhichseiningwasdone.Thisissimilartothefindings surface, andthatinLakeClaire,Alberta,spawningoccurredquiet structure ofriverandlakegoldeyepopulationsdifferedmarkedly(Figure ing mightbeexpectedintheSaskatchewanlateMay orJune.Sprules non-flowing wateratatemperatureof50°F.(10°C.)(Sprules,1949b). at LakeClaireisofgeneralapplication,thenitwould appearthatspawn- plus thecurrentsummer'sgrowth.OnAugust5atFenton, tengoldeyes Petrofka onJuly11andwere35to40mm.inforklength.Bytheendof May 28atLeader,agoldeye102mm.longwithone annulus wasseined. The smallestgoldeyesobtainedduringthepresentstudywereseinedat heavier thanarelakefishofthesameage(Figure11).Moreover, these fishhadnoannuliandwerepresumablyyoung-of-the-year. On the firstweekofAugust,younggoldeyeswerefrom60 to85mm.inlength. for thisdifferenceinagestructureisnotclear. Another obtainedAugust20atOutlookwas158mm. and hadoneannulus In September,goldeyes105mm.inlengthweretaken intheOldChannel; were eight,andsomenine-ten-years-oldcaptured.Thereason 12). NofishovertheageofsevenwereobtainedinCumberlandLake (1949a) suggestedthatgoldeyesdonotmakeextensive migrations.He ( Reed, 1959,unpublished).However,nearly13percentoftheriverfish Fig. 12.—Agecompositionofthetotalgill-netcatchesgoldeyefrom After earlyJuly,goldeyeyoung-of-the-yearweretakeninnearly Without givingdetails,Sprules(1949a)statedthat goldeyesinthe PERCENTAGE 20 25 I I 0 5 5 North andSouthSaskatchewanRivers(stippledbars)from Cumberland Lake(openbars). 7-T

p. ■10

2 3

AGE 4 37 I 5 N 9 I

0 • ■■•

reaches of the Saskatchewan suggests the possibility of an upstream spring spawning run. The following observations may indicate extensive goldeye movements: numerous fry in the upper reaches; capture in The Pas area of fish tagged near Cumberland House; trapping of adults and fry moving downstream; differences in age structure of river and Cumber- land Lake populations; capture of only older age groups and fry in the North Saskatchewan following apparent unsuitable winter conditions in the river. Nineteen walleyes, the largest of which was 25.2 inches in length and seven pounds in weight, were taken from the three rivers. From this small sample, the following data were derived:

Average fork Average weight Age length inches ounces

1 9.5 3.8 2 12.3 11.4 5 15.0 21.0 6 16.6 28.0 7 19.0 48.0 8 19.5 53.0 Growth of the river walleyes is somewhat faster than that recorded for Lac la Ronge walleyes by Rawson (1957b). Walleye fry were obtained after July 8 by seining at Maymont, Frenchman Butte, Estuary, Codette, and below White Fox. Fork length at the time of first annulus formation appeared to vary considerably. A walleye 145 mm. long taken June 25 at Cecil had just formed the first annulus; a fish 230 mm. seined at Saskatoon on June 3 was forming the first annulus. Two walleyes, seined below White Fox, were 150 and 170 mm. in length and each had two completed annuli. With these fish were two smaller walleye 66 and 70 mm. which did not show annulus formation. Young walleyes were distinguished from small sauger on the basis of the number of pyloric caeca (finger-like projections from the stomach). Fish with three caeca were considered to be walleyes and those with four or more were regarded as sauger. Seventeen pike, the largest of which weighed 6.2 pounds, were taken from widely scattered locations on the North and South branches and from the main river. The pike in the Saskatchewan River appear, on the basis of this small sample, to be growing at a rate comparable to that recorded by Rawson and Atton (1953) for Lac la Ronge pike. Growth data for the river fish were as follows: Age Average fork Average weight years length inches ounces 3 18.5 28 4 21.3 35 5 25.5 82 Age determinations were made from the scales of 56 northern redhorse suckers from the South Saskatchewan and 41 from the North Saskatchewan Rivers. It is interesting that no redhorses less than seven years of age were taken by gill netting in the North Saskatchewan. In fact, only six of the fish were actually netted in the North Saskatchewan proper; most were taken from the Battle River just above its confluence with the North. Age distribution appeared to be better balanced in the South Saskatchewan River. Most of the redhorses taken from the South were netted near Saskatoon. However, distribution in the South appears to be more widespread than in the North. Rate of growth of the Saskat- chewan redhorses is much slower than that given by Carlander (1950 and 1953) for Minnesota and Oklahoma fish. The Saskatchewan fish are 38 also much lighter in weight for any given length than are the southern fish. The catch from both the North and South Saskatchewan was combined and the following growth data derived: Age Fork length Weight years inches ounces 1 -- 2 3.3 -- 3 4.4 2 4 10.6 10 5 12.0 12 6 -- -- 7 13.2 17 8 14.0 22 9 14.7 24 10 15.4 30 11 15.5 31 12 16.5 40 Examination of the scales indicated that some redhorses may be only 44 mm. long at the start of the second summer and that some are as small as 77 mm. at the beginning of the third summer. Age determinations were made from the scales of 27 longnose suckers taken from the North Saskatchewan River and from 38 fish from the South Saskatchewan. The average fork lengths and weights differed in the two groups as may be seen in the following growth data: North Saskatchewan South Saskatchewan Age No. Length Weight No. Length Weight years fish inches ounces fish inches ounces 3 1 12.7 14 2 11.6 10 4 6 15.1 23 7 14.0 18 5 13 16.8 35 20 14.5 20 6 7 17.3 39 9 15.8 25

The rate of growth of the South Saskatchewan longnose suckers was similar to that observed by Kathrein (1950) for longnose suckers from a section of the Missouri River in Montana. Longnose sucker fry were seined in the North Saskatchewan at Old Maymont ferry, Petrofka, and Frenchman Butte. The fry had reached a length of 30 to 50 mm. by July 10. Fish Food In food habits, the fish of the Saskatchewan River may be divided into two large groups; the piscivorous species including sauger, walleye, pike, and burbot and the other species which feed chiefly on inverte- brates, algae, and detritus. The stomachs of 58 piscivores obtained by gill netting were examined with the following results:

Number of Stomachs Stomachs stomachs Empty containing containing examined stomachs fish remains insects Sauger...... 14 7 7 0 Walleye ...... 25 17 7 1 Pike...... 20 14 5 1 Burbot ...... 9 5 4 0

It is known that fish caught in gill nets sometimes regurgitate the stomach contents. Thus the number of empty stomachs may be disproportionately 39 large. Most of the stomach contents were too well digested to be identifiable. However, one 11-inch goldeye, a 14-inch burbot, and several three- to five-inch longnose suckers were found in pike stomachs. One pike stomach contained a mallard duckling. Insects are the principal food of the goldeyes and various suckers found in the Saskatchewan River. Mayfly nymphs of the family Ephe- meridae composed about 90 per cent of the bulk of the stomach contents of the goldeyes examined. Caddis fly and chironomid larvae were next in importance. Water boatmen (bugs of the family Corixidae ) were utilized extensively, at times, as were grasshoppers. Terrestrial insects falling into the water and insects flying near or ovipositing on the water surface were fed upon by goldeyes. Only one goldeye stomach contained fish remains. Rawson (1947) indicated that the larger goldeyes in Lake Athabaska regularly fed on small fish. Sprules (1947) found that young pike formed most of the food of goldeyes caught in Lake Claire, Alberta. Mayfly nymphs (usually not Ephemeridae) were important in the diet of northern redhorse suckers, but chironomids were the most important constituent in the food of the other sucker species. Amphipods, dragonfly nymphs, molluscs, and small crustaceans were used in minor amounts. Stomach or gut contents from a few fish taken by seining were examined to determine, in a general way, the food of young fish of different species. Walleyes as small as 46 mm. contained sucker fry; two of eight stomachs contained immature aquatic insects. Young northern redhorses, goldeyes, longnose suckers, and shiners had fed on insects and small crustaceans. Clearly, with the exception of the piscivorous species, aquatic insects are the principal item of food of the Saskatchewan River fish. The aquatic insects play an important role in fish production in the river by converting energy stored in plants (chiefly algae) to a form which can be utilized by fish. Fish Parasites Fish were not systematically examined for parasites, but parasites encountered in the routine handling of the fish were preserved. Dr. M. C. Meyer, University of Maine, identified the leeches; Dr. Paul Illg, Uni- versity of Washington, identified the Crustacea. Dr. L. Margolis, Bio- logical Station, Nanaimo, determined the cestodes. Parasites and hosts were: Leeches: Myzobdella moorei (Meyer )—longnose sucker Actinobdella triannulata Moore—common and longnose suckers Crustaceans: Lernaea catostomi (Kryer )—common sucker, longnose sucker, northern redhorse sucker Argulus appendiculosus C. B. Wilson—goldeye Cestode: Bothrio:Tphalus cuspidatus Cooper—goldeye. The percentage of fish with external parasites was small. About 85 per cent of the goldeyes were infested with tapeworms. The worms were found mainly in the intestine and, of course, did not affect the food quality of the fish. A large number of goldeyes was found to harbour an unidentified trematode parasite in the body cavity. These flukes, about one-fourth inch long, were observed moving about between the 40 viscera and the body wall. A few unidentified nematodes were found in the stomach contents of goldeyes and in the gut contents of longnose suckers.

Pollution Introduction One of the chief problems of the day, in the face of a rapidly enlarging population and expanding industry, is to secure adequate supplies of suitable water. Pollution of rivers by domestic and industrial wastes has often occurred with urbanization and with changes in agricultural practices. Tarzwell (1952) classified water pollutants in five categories, namely (1) inert inorganic substances, (2) putrescible wastes, (3) toxic wastes, (4) radioactive wastes, and (5) wastes of significant heat content. The degree of pollution of the principal rivers of the Saskatchewan system in Saskatchewan is not easily estimated because of the seasonal aspects of pollution and because possible sources of pollution are unevenly spread over a large geographic area. Research in the field of aquatic pollution in the past thirty years has indicated the complex nature of problems involving the effect of different chemicals on aquatic environments and their inhabitants. Temperature, pH, and chemical composition of the effluent and of the receiving water greatly influence toxicity. Some chemicals which are toxic alone may be rendered innocuous by the presence of certain other chemicals and, conversely, the effect of some chemicals of low toxicity may be magnified many fold when in combination with other substances. The turbid condition of the North, the South, and the Saskatchewan Rivers during much of the ice-free period of the year indicates that all three are subject to inert inorganic pollution. Runoff from heavy rains in the clay badlands along the Red Deer River colours the waters of the South Saskatchewan and the Saskatchewan River to Cumberland House with red clay particles. In cities and along highways, natural silting has been augmented by the discharge from storm sewers and drains. Radioactive wastes and heat content are not known to be problems at present. Putrescible and toxic wastes frequently occur together particularly in urban areas. Harmful effects of putrescible wastes may be the reduction of dissolved oxygen to the point of exhaustion, or growth of undesirable fungi, phytoplankton, or bacteria. Furthermore, the toxic effects of certain chemicals are enhanced by low oxygen tensions. Domestic sewage is, of course, one of the chief sources of putrescible wastes, but many industrial processes also produce residues rich in organic matter. Organic material, upon entering a river, begins to undergo bacterial decomposition. The first bacteria are aerobic and must have oxygen for respiration. If the number of aerobic bacteria is great enough to exhaust the available oxygen supply, anaerobic bacteria continue the processes of decay. Decomposition ultimately results in the organic material being reduced to its mineral components. The foul odours associated with decomposing organic matter are often the result of anaerobic decomposition. In rivers, this type of decomposition marks the zone of most severe pollution. Calgary, Lethbridge, and Medicine Hat are the principal centres of population on the South Saskatchewan and its tributaries in Alberta; of these, Medicine Hat is the closest to the Saskatchewan border, being some 110 miles by river (Dennis and Challies, 1916). The South Saskatchewan was examined at the Empress ferry on two occasions, July 24, 1957, and July 21-22, 1958. On neither visit were indications of gross pollution seen. 41 The Red Deer River joins the South Saskatchewan a few miles below the Empress ferry. The largest centres of population on the Red Deer are the towns of Red Deer and Drumheller, the latter being about 150 miles above the forks of the two rivers. Probably little organic or toxic wastes reach the South Saskatchewan through this river. It is clear that the North Saskatchewan River before reaching the Alberta-Saskatchewan boundary has suffered gross pollution. Investiga- tions by the Fisheries Branch, Saskatchewan Department of Natural Resources, indicated that domestic sewage and industrial wastes originating Edmonton are the causative agents (Atton, 1954). Apparently the industrial wastes are of a complex nature involving both organic and toxic substances. It has been pointed out (Atton, 1954, and in this study) that the dissolved oxygen content of the North Saskatchewan River in this province is practically nil during the season of ice cover. The ice cover prevents ready re-oxygenation of the water at the river surface, retards recovery, and extends the area of severe pollution much further downstream in winter than during the open-water season. The evidence of pollution in the summer is not as dramatic as in the winter, but is never- theless convincing. The North Saskatchewan, as it enters the province at Frenchman Butte, carries large quantities of organic material as indicated by the presence of foul-smelling deposits in quiet water. Large numbers of tubificid worms and red chironomids, animals associated with decaying organic muck, were collected from the bottom mud. Sphaerotilus, the "sewage-fungus", grew attached to rocks on the river bed. The composition of the fish populations of the North and the South Saskatchewan Rivers suggests some fundamental differences. Of the 24 species of fish recorded during the two-year survey, three were taken only in side streams. These were the mountain sucker, pearl dace and lake chub. Of the remaining 21 species captured in the South Saskatchewan, seven were not taken in the North Saskatchewan. These included the sturgeon, silver redhorse, sauger, emerald shiner, river shiner, yellow perch and troutperch. Records showing that some of these species did occur formerly in the Prince Albert area are in the Fisheries Laboratory files. The significant point is the extreme scarcity, if not absence, of such species as the emerald shiner, river shiner, and flathead chub. These fish are the characteristic species in the South Saskatchewan and Saskatche- wan Rivers. Origin of water, topography, and soils of the drainage basins of both the North and the South are so similar that it appears doubtful if such environmental factors could explain the differences in occurrence of these species in the two rivers. If, as seems possible, winter-killed stocks are replenished in the North by extensive immigration, the shiners and chubs may not travel far during one season. The scarcity of young fish of the species which were taken in the North Saskatchewan, further suggests that conditions are not suitable to maintain populations.

Sources of Pollution within the Province Having considered the condition of the waters of the North and South Saskatchewan Rivers where they enter the province, the question arises as to the effects exerted upon these waters within the province. North Battleford and Prince Albert are the only cities on the North Saskatchewan River between its junction with the South and the western boundary of the province. North Battleford makes no major industrial use of water. Prince Albert has two meat-packing plants, a brewery, a foundry, a refinery, and a power plant. To wastes from the industrial sources can be added the wash water from railway shops, small businesses 42 and domestic sewage. Both North Battleford and Prince Albert discharge raw domestic sewage into the river. Along the south bank of the river in Prince Albert a large, and at times, strong-smelling sludge bed resulted from the deposition of organic material and was observed to extend from the sewer outfall for several blocks downstream. The sludge bed contained large numbers of tubificid and lumbriculid worms. Rocks in the river bed as far downstream as Cecil Ferry, about 15 miles, showed a black sulphide coating denoting anaerobic decomposition of organic matter. Saskatoon is the only large centre of population on the South Sask- atchewan River in Saskatchewan now discharging domestic and industrial wastes into the river. Possibly within a few years, wastes entering the river in the Outlook-Elbow region will reach significant proportions. Unlike the situation on the North Saskatchewan, the South reaches the city of Saskatoon in a relatively good condition. Thus it is possible to assess rather closely the impact of wastes from Saskatoon upon the river. Saskatoon sewage is collected in a series of drains and pumped to a central station, where the solid material is shredded and the effluent discharged into the South Saskatchewan without further treatment. The sewer outfall is in the midstream current, which facilitates rapid mixing and prevents the formation of sludge beds adjacent to the outfall. The city is serviced by a network of storm sewers which eventually drain into the river via large trunk sewers. It was observed early in the survey that certain of the storm sewers were discharging domestic sewage, particularly the 23rd Street sewer. During low water a sludge bed of putrid black mud accumulated immediately downstream from the outlet. Chemical analyses of the water at different times indicated that industrial wastes were discharged through this sewer also. The volume of flow passing through the 23rd Street sewer is not known; probably it is small when compared to the total effluent of the city. However, water resources for recreation in the Saskatoon area are decidedly limited and many people fish, wade, and picnic along the bank of the river below the city. The practice of discharging untreated sewage along the banks of a river immediately above a recreation area is revolting aesthetically and a menace to health. Observations made during the period of ice cover indicated that sewage originating in Saskatoon was making a noticeable effect on the South Saskatchewan River. The following determinations of oxygen in the river water indicate that a considerable amount was required to oxidize the organic matter in the sewage: Clarkboro Feb. 4, 1957 8.0 c.c./1. 81% saturation St. Louis Feb. 11, 1957 6.5 c.c./1. 66% saturation Clarkboro Feb. 26, 1957 7.6 c.c./1. 77% saturation Hague Jan. 21, 1958 8.4 c.c./1. 84% saturation St. Louis Mar. 25, 1958 8.5 c.c./1. 86% saturation The values are not critical but do denote that a noticeable amount of oxygen was being removed. When the oxygen concentration at Hague was 8.4 c.c. /1., the value at Yorath Island, above Saskatoon, was 9.3 c.c./1. A reduction of .9 c.c./1. in the water volume of the time indicated that about 16,000 pounds of dissolved oxygen had been removed from the river in passing between the two stations. Thomas (1956) listed eight principal industrial users of water (and, therefore, sources of wastes) in Saskatoon; a refinery, a meat-packing plant, flour mills, a foundry, two breweries, a power plant. An important 43 recent addition is a fibreboard plant in which wheat straw and wood pulp are used to produce building materials. An exploratory investigation revealed that the effluent of the fibreboard plant was of a very low toxicity to fish. However, the organic content both in solution and as fibres had a high biological oxygen demand, meaning that the reduction of the organic material to its mineral constituents by bacterial action required large amounts of dissolved oxygen. Observations on the Saskatchewan River below the forks of the North and the South are not as numerous as for each branch. Atton (1954) recorded a series of dissolved oxygen determinations made from the forks to Cumberland House. Oxygen measurements indicated that the North and the South continued side by side as discrete streams under the ice for at least eight miles below their confluence. The North Saskatchewan water was identifiable by the low oxygen content. The South Saskatche- wan flow contained 9.9 c.c./1. of dissolved oxygen 2.5 miles below the forks, and the North flow had 0.7 c.c./1. On February 12, 1957, further observations were made at the forks. On this occasion the dissolved oxygen content of the North was 1.1 c.c./1., and that of the South was 7.7 c.c./1. Each sample was taken a short distance above the confluence of the two rivers. The 1957 value for the South was substantially less than the 1954 values reported by Atton. One oxygen reading is not sufficient evidence to indicate that the winter condition of the South has deteriorated markedly in three years, but it is interesting to note that the 1954-57 period was one of rapid growth in the population of Saskatoon. Summary of Present Pollution Conditions The current status of pollution (1958) in the North and South Sask- atchewan Rivers may be described thus: (1) The North Saskatchewan suffers from gross pollution before reaching Saskatchewan. The oxygen content in winter is at or below 1 c.c./1. It is difficult to understand how fish could over-winter in any numbers in the river. Evidence from the fish fauna suggests that the fish either die or migrate. The cities of North Battleford and Prince Albert are not exerting a great influence on the situation in the North Saskatchewan at present. If pollution is remedied to the west, the domestic and industrial wastes of Prince Albert could conceivably produce a limited but noticeable effect on the river in the winter. (2) The South Saskatchewan arrives at Saskatoon in a relatively unpolluted condition. The combined domestic and industrial wastes of Saskatoon are now producing noticeable effects on the river, particularly under ice cover. (3) The Saskatchewan between the forks and Cumberland Lake shows the effect of the polluted condition of the North during winter. The volume of the river in relation to volume of wastes prevents serious pollution during summer. Possible Future Developments The story of pollution of streams and rivers is an old one and has been recorded many times, wherever large numbers of people have gathered along rivers—in Europe, in Asia, and in North America. Un- checked dumping of domestic and industrial wastes always leads to the destruction of the original fauna and flora of the receiving stream; it is merely a question of time, depending on the relative volume of effluent to receiving water. Public apathy, refusal of vested interests to take the 44 responsibility for their waste products, and the reluctance of admini- strators to arouse the hostility of industry or taxpayers; seem to be the contributory factors in the continued practice of water pollution by both industry and domestic agents. Gross pollution in the North Saskatchewan River has commanded government attention since 1954. Some improve- ments in the situation have resulted, but they have not been sufficient to keep the North from becoming an uninhabitable environment for fish in the winter. The South Saskatchewan has escaped a similar fate only because the population living along the tributary streams is smaller and more dispersed than is that on the North. Also along the South there is no concentration of industry comparable to that found in the Edmonton area. The greatest threat on the South at present appears to be Saskatoon. If domestic and industrial wastes are permitted to bring about oxygen exhaustion in this river between Saskatoon and the forks, the entire fish population of the Saskatchewan will be in jeopardy. Oxygen exhaustion in the South below Saskatoon comparable to that in the North, would make conditions unfit in winter for fish as far downstream as Cumberland House at least. In spite of the poor winter conditions in the North Sask- atchewan, a moderate amount of angling exists now in the summer, apparently supported by immigration of fish from areas unaffected by severe winter conditions. If such conditions are allowed to develop in the South below Saskatoon, these stocks will be lost and the entire angling resource of the North, the South below Saskatoon, and the Saskatchewan from the forks to the Manitoba boundary may disappear.

Summary and Conclusions 1. Volume of flow in the Saskatchewan River varies from year to year and from season to season within one year. The volume of high water may exceed that of low water by 100 fold. Normally two flood periods occur, one in spring and one in summer. 2. In non-flood periods, the rivers tend to be rather shallow, usually varying from six to ten feet in depth. The predominant bottom type is sand interspersed with stony rapids. 3. The maximum observed surface temperature was 26.0°C. Surface temperatures are in the range 19 to 22°C. from late June through August. Vernal warming and autumnal cooling proceed rapidly. 4. The chemical quality of water in the South, North and Saskatche- wan Rivers varies greatly from summer to winter. Under the winter ice cover, the content of bicarbonate, chloride, and hardness increases, pH becomes lower. Dissolved oxygen content changes markedly in the North Saskatchewan with the advent of the ice cover, decreasing to about 1 c.c. per 1. Less severe oxygen reduction occurs in the South during winter. 5. Plankton populations are low but not excessively so when compared to other large, turbid rivers. 6. Dry weight of the average standing crop of bottom fauna in the South Saskatchewan was 3.3 kg. per ha. (2.9 lbs. per ac. ) for muddy and silty bottoms and 5.7 kg. per ha. (5.1 lbs. per ac. ) for stony riffles. Corresponding values in the North Saskatchewan were 1.9 (1.7) and 3.4 (3.0) respectively. Riffles in the Saskatchewan had an average standing crop of bottom animals of 7.1 kg. per ha. (6.3 lbs. per ac. ). 7. Twenty-four species of fish were captured by gill-netting and seining. The goldeye, longnose sucker, and northern redhorse sucker are 45 the most numerous species in the North and South Saskatchewan Rivers. Secondary species are the pike, walleye, and common sucker. The average catch per 50 yards of three-inch mesh gill net in the North Saskatchewan was 16.6 fish which weighed 20.5 lbs.; the catch for four-inch mesh was 11.0 fish and 28.4 lbs. The average catch per 50 yards of three-inch mesh gill net in the South Saskatchewan was 13.5 fish which weighed 17.0 lbs.; the catch for four-inch mesh was 14.5 fish and 26.9 lbs. The catches of the three- and four-inch mesh nets correspond roughly to catches from the less productive lakes of Saskatchewan. 8. A substantial, but unmeasured, sport fishery exists on the South, North, and Saskatchewan Rivers. Goldeyes and pike, with lesser numbers of walleyes, are the chief angling species. Considerable numbers of rough fish, particularly longnose and northern redhorse suckers, are taken by anglers. 9. In 1958, 189 licenses for domestic gill nets to be used in the South, North or Saskatchewan were issued; about 82 per cent were used. The average catch per license was 44 game fish of which about 38 per cent were goldeyes. On a daily basis, the average catch per license did not exceed the angling limit. There is no indication that the domestic gill-net fishery is affecting the angling adversely at this time. 10. Goldeyes taken from the rivers are longer and heavier than those of the same age from Cumberland Lake. Age structure of the river and of the lake populations appears to be different, older age groups being much more important in the river populations while younger age groups pre- dominate in Cumberland Lake. 11. The South Saskatchewan River enters the province in a relatively unpolluted condition. The North Saskatchewan on entry into the province shows the effects of pollution especially in winter when the river is ice- covered. Industrial wastes and domestic sewage originating in Saskatoon are now producing a considerable demand upon the dissolved oxygen of the South Saskatchewan River below Saskatoon. The entire angling resource of the Saskatchewan River system in Saskatchewan will be imperilled if the release of wastes into the river at Saskatoon is allowed to continue in an uncontrolled manner.

References AMERICAN PUBLIC HEALTH ASSOCIATION. 1955. Standard methods for the examination of water, sewage, and industrial wastes. Amer. Pub. Health Assoc. Inc. New York. 522 pp. ATTON, F. M. 1954. North Saskatchewan River pollution. Unpub. Rept., Fisheries Branch, Dept. Nat. Res., Sask. 24 pp. ArroN, F. M. and MURRAY, A. R. 1952. Fisheries investigation of Last Mountain Lake, Saskatchewan, 1950, 1951. Unpub. Rept., Fisheries Branch, Dept. Nat. Res., Sask. 78 pp. CARLANDER, K. D. 1950. Handbook of freshwater fishery biology. Brown. Dubuque, Iowa. 281 pp. 1953. First supplement to handbook of freshwater fishery biology. Brown. Dubuque, Iowa. pp. 277-429. DAMANN, K. E. 1951. Missouri River Basin plankton study. Federal Security Agency, Pub. Health Service, Environmental Health Center. Cincinnati. 100 pp. 46 DENNIS, L. G. and CHALLIES, J. B. 1916. Water-powers of Manitoba, Saskatchewan and Alberta. Rept. of Comm. on waters and water- powers. Commission of Conservation. Toronto. 334 pp. DOTY, M. S. and OGURI, M. 1957. Evidence for a photosynthetic daily periodicity. Limnol. and Oceanogr., 2 (1): 37-40. HOGG, T. H., GAHERTY, G. A., and WIDTSOE, J. A. 1952. Report of the Royal Commission on the South Saskatchewan River Project. Ottawa. 423 pp. KATHREIN, J. W. 1950. Growth rate of four species of fish in a section of the Missouri River between Holter Dam and Cascade, Montana. Trans. Amer. Fish. Soc., 80: 93-98. MANN, K. H. 1958. Annual fluctuations in sulphate and bicarbonate hardness in ponds. Limnol. and Oceanogr., 3 (4): 418-422. MENDIS, A. SEPALA. 1956. A limnological comparison of four lakes in central Saskatchewan. Unpub. M. Sc. Thesis, Dept. Biology, Univ. of Sask. 103 pp. MILLER, J. 1914. A field method for determining dissolved oxygen in water. Jour. Soc. Chem. Ind., 4 (8): 185-186. NOVAKOWSKI, N. S. 1955. The ecology of Reindeer Lake with special reference to fish. Unpub. M. Sc. Thesis, Dept. Biology, Univ. of Sask. 99 pp. ODUM., H. T. 1956. Primary production in flowing waters. Limnol. and Oceanogr., 1 (2): 102-117. RAWSON, D. S. 1947. Lake Athabaska. Bul. Fish. Res. Bd. Can., 72: 69-85. 1957a. The limnology and fisheries of five lakes in the upper Churchill drainage, Saskatchewan. Fisheries Rept. No. 3, Fisheries Branch, Dept. Nat. Res., Sask. 61 pp. 1957b. The life history and ecology of the yellow walleye, Stizostedion vitreum, in Lac la Ronge, Saskatchewan. Trans. Amer. Fish. Soc., 86: 15-37. 1959. The limnology and fisheries of Cree and Wollaston Lakes in northern Saskatchewan. Fisheries Rept. No. 4, Fisheries Branch, Dept. Nat. Res., Sask. 73 pp. and ATTON, F. M., 1953. Biological investigation and fisheries management in Lac la Ronge, Saskatchewan. Fisheries Rept. No. 1, Fisheries Branch, Dept. Nat. Res., Sask. 40 pp. REED, E. B. 1959. The limnology and fisheries of Cumberland and Namew Lakes, Saskatchewan. Unpubl. Rept. Fisheries Branch, Dept. Nat. Res., Sask. 83 pp. RUGGLES, C. P. 1959. Biological and fisheries survey of Lac la Plonge and Canoe Lake. Unpub. Rept. Fisheries Branch, Dept. Nat. Res., Sask. 91 pp. SCOTT, W. B. 1958. A checklist of the freshwater fishes of Canada and Alaska. Royal Ontario Museum. Toronto. 30 pp. SPRULES, W. M. 1947. Goldeye investigation in 1947. Ann. Rept. Central Fisheries Res. Sta. pp. 15-17. 47 1949a. Evidence of the natural propagation of goldeye, Amphiodon alosoides, in the upper South Saskatchewan River. Mimeo. Rept. Central Fisheries Res. Sta. 5 pp. 1949b. The embryonic development of goldeye. Ann. Rept. Central Fisheries Res. Sta. pp. 48-49. TARZWELL, C. M. 1952. Application of biological research in the control of industrial wastes. Proc. Nat. Technical Task Committee on Ind. Vv astes. Environmental Health Centre, Cincinnati. pp. 1-19. THEROUX, F. R., ELDRIDGE, E. F., and MALLMANN, W. L. 1943. Lab- oratory manual for the chemical and bacterial analysis of water and sewage. 3rd ed. McGraw-Hill. New York. 274 pp. THOMAS, J. F. J. 1953. Scope, procedure, and interpretation of survey studies. Industrial water resources of Canada. Water Survey Rept. 1. Ottawa. 69 pp. 1956. Saskatchewan River drainage basin, 1951-52. In- dustrial water resources of Canada. Water Survey Rept. 7. Ottawa, 154 p.p.

Also Available from the FISHERIES BRANCH Department of Natural Resources, Prince Albert Fisheries Report No. 1—BIOLOGICAL INVESTIGATION AND FISHERIES MANAGEMENT AT LAC LA RONGE, SASKATCHEWAN. By D. S. Rawson and F. M. Atton, 1953. Fisheries Report No. 2—A LIMNOLOGICAL COMPARISON OF FOUR LAKES IN CENTRAL SASKATCHEWAN. By A. S. Mendis, 1956. Fisheries Report No. 3—LIMNOLOGY AND FISHERIES OF FIVE LAKES IN THE UPPER CHURCHILL DRAINAGE, SASKATCHEWAN. By D. S. Rawson, 1957. Fisheries Report No. 4—LIMNOLOGY AND FISHERIES OF CREE AND WOLLASTON LAKES IN NORTHERN SASKATCHEWAN. By D. S. Rawson, 1959. Fisheries Report No. 5—FIVE LAKES ON THE CHURCHILL RIVER NEAR STANLEY, SASKATCHEWAN. By D. S. Rawson, 1960.

Printed by Lawrence Amon, Printer to the Queen's Most Excellent Majesty, Regina, Saskatchewan 1961 coieNwi 48