flSHERIESRESEARCHROARDor 8!0L0GICALSTATlON,

ST. JOliN'S. NEI'IFOUNDlAND. OANAOA FISHERIES RESEARCH BOARD OF CANADA

MANUSCRIPT REPORT SERIES

No. 1037

TInE

Bleached Kraft ~1i11 Effluent near , N.S. anu its Effect on the ~Iarine Flora anu Fauna with a Note on the Pictou Co. Lob5ter Landings

AUTHORSHIP

D. J. Scarratt

Establishment Biological Station, St. Andrews, N. 1:1.

Dated November 1969

This se;ies includes unpublished preliminary reports and doto records not intended for general distribution. They should not be referred to in publicotionswithout clearance from the issuing Boord establishment and without cleor indication of their manuscript status.

FISHERIES RESEARCH BOARD OF CANADA

MANUSCRIPT REPORT SERIES

No. 1037

TITLE

Bleached Kraft ~lill Iiffluent near Pictou. N. S. and its Effect on the ~larine Flora anJ Fauna with a Note on the Pictou Co. Lobster Landings

AUTHORSHIP

n. J. Scarratt

Establishment

Biological Station, St. Andrews. N. Il.

Dated Novemher 1969

This se;ies includes unpublished preliminary reports and data records not intended for general distribution. They should not be referred to in publicotions without clearance from the issuing Board establishment and without clear indication of their manuscript status. BLEACHED KRAFT MILL EFFLUENT NEAR PICTOU, N. S. AND ITS EFFECT ON THE MARINE FLORA AND FAUNA WITH A NOTE ON THE PICTOU CO. LOBSTER LANDINGS

By D. J. Scarratt

In September 1967, a 500 ton/day bleached kraft mill became fully operational at Abercrombie Point, , N. S. Freshwater effluent is piped at the rate of 20 million gal/day into a settling pond where it is held for 4 days before entering Boat Harbour. After an estimated 40-day retention period, it escapes through a diffuser pipe into the head of Boat Harbour inlet which opens into the sea about 1 mile southeast of the entrance to Pictou Harbour (Fig. 1). Res idua1 surface drift in the area is of the order of 1.5-3.5 miles per day to the east (Lauzier, 1965) and the effluent is carried in that direction in a narrow stream which keeps close to the shore past Mackenzie Head and is visible at least as far as Roaring Bull Point 3 miles distant. Earlier studies (Scarratt, 1969; Sprague and McLeese, 1968) had indicated no likelihood of immediate or direct effects of the effluent upon lobsters. There were, however, complaints from fishermen that lobsters were considered to be leaving the area. In response to this, brief surveys were made on May 26 and 27 and August 19-21, 1969. This report describes these surveys, presents an account of the lobster landings in Pictou County since 1952 and concludes that the area exposed to high concentrations of BKME is relatively small and there is no evidence for attributing declining lobster landings to the effluent.

METHODS

Survey 1 - May 26-27, 1969 This survey was in two parts: a) Hydrographical survey Beginning at Boat Harbour dam, a series of surface water samples were taken from 11 stations along the shore (Fig. 1). The following properties were measured : dissolved oxygen content by the modified Winkler method, specific gravity, temperature and concentration of effluent (Table 1). The latter was determined colorimetrically by comparing each sample with a series of standards made by mixing known proportions of effluent and clean sea water taken several miles offshore. Salinity was calculated from specific gravity and temperature records using Knudsen tables. -Z-

Five stations were occupied further offshore (Fig. 1) and water samples taken at the surface, bottom and several intermediate depths. Specific gravity, temperature, Oz content and effluent concentration were determined as before. Two of the stations were 1/4 and l/Z mile off the mouth of Boat Harbour and the other three were at 1/4- mile intervals off Mackenzie Head. Onshore winds prevented the research vessel from moving closer inshore. b) Biological survey

A brief, visual macroscopic examination was made of the flora and fauna at each of the 11 shore stations, and several photographs were taken (Fig. Z-6). These observations are summarized in Table 1. Scuba dives were made and the sea bed examined at Mackenzie Shoal (Station E, Fig. 1) and also off Logan Point. Depth at each station was about 5 m. Lobster traps were set in both areas. It seemed possible that Mackenzie Shoal would receive some effluent but unlikely that Logan Point would be affected and this area was regarded as a control.

Survey Z- August 19-Zl, 1969

This survey similarly was in two parts: a) Hydrographical survey This extended from above Boat Harbour dam throughout the course of the effluent stream into the open sea and for a distance thereafter, and was coupled with spot checks at various places outside the apparent effluent stream (Fig. 6, 7). Clement weather and the use of a small boat permitted samples to be taken in the centre of Boat Harbour entrance, and at several places very close to shore along the open coast. Temperature and salinity were determined as before, and dissolved oxygen concentration was determined in the more concentrated parts of the effluent stream. Colorimetric determination of effluent concentration was made for samples from all stations. All samples were retained and their pH and U. V. absorption spectra were subsequently measured by Dr. V. Zitko at St. Andrews. Concentration (C) of effluent for each sample (n) was calculated from

(1)

where A is the U. V. absorbance of that sample. 0.035 is Z50n -3-

the A of clean St. Andrews sea water and 8.7 is the A ZSO ZSO of undiluted effluent from the surface of Boat Harbour lagoon (sample D). Concentrations are expressed as percentages. Surface samples were taken at all stations, together with samples near bottom and occasionally at an intermediate depth in or near the apparent effluent stream (Tables 3, 4). b) Biological survey Underwater observations of the sea bed were made at Mackenzie Head and Roaring Bull Point inside the effluent stream and at Cole Point, Logan Point and Seal Rock which are outside it. Seal Rock and Roaring Bull Point are about equi­ distant from Boat Harbour, upstream and downstream respectively.

RESULTS

Survey 1 (Spring) - Hydrography and littoral observations The sample taken from Boat Harbour above the dam (station 1) was regarded as 100% effluent and was used as a colour standard. It contained no oxygen (Table 1). There was no apparent flora or fauna in the lagoon. On the downstream side of the dam (station 2) there was considerable mixing of effluent with sea water at the outfall; the salinity had increased to l8%., colour had decreased to 40%, and dissolved oxygen content was 30% of saturation. One stickleback (Gasterosteus acuZeatus) and one other unidentified larger fish were seen. At station 3 there were several live isopods high on the rubble bank but only the empty shells of barnacles and periwinkles could be found on adj acent rock outcrops (Fig. 2). Closer to the mouth of the harbour entrance (station 4) the mudflats did not appear to support any clams or other species. The small lagoon (station S) inside the entrance . s only flooded by the tide occasionally and the low salinity and low colour indicate that it receives drainage directly off the higher land behind. Dissolved oxygen concentration was high (80\ saturation). There were several unidentified fish in the lagoon. By the sandy bank just inside the harbour entrance on the west gt~:id~o~~~rh:~~o~~o~~~r;~~ea~~e~~ ~~~~e~iv:O~a~~a~~~~r~~~o~~ri_ winkles on the rocks (Fig. 3) and isopods, amphipods and various polychaetes under them. There was a narrow tongue of clean sea water spilling into the entrance over the sand bar from the west (station 7, Fig. 4) and presumably some clean water entering under the outgoing, less dense, partially diluted effluent. On the east side (station 8), salinity was lower and colour higher than on the west side, indicating that the effluent was being held on shore by the wind, but higher O concentration (90% saturation) shows 2 that wave action and turbulence on the beach were promoting oxidation of the effluent. There was considerable foam (Fig. 5). In the cove between Powell Point and Mackenzie Head, effluent concentration was down to 4% and at Mackenzie Head it was 2%. At Roaring Bull Point the effluent was barely detectable in small samples but the sea was plainly discoloured. The shore­ line between the cove and Roaring Bull Point appeared devoid of deleterious biological effects due to the effluent; however, there was a detectable odour to the water and some foam along the strand line even at Roaring Bull Point. The effluent stream was not followed any further to the east.

Under conditions existing during the May survey--moderate onshore breeze and falling tide--the effluent was plainly visible as a darker streak of water never more than 250 m wide and frequently less, extending from the mouth of Boat Harbour easterly to Roaring Bull Point. No effluent was detectable at the offshore - stations and oxygen concentrations were high at all depths (Table 2). At other stages of the tide, effluent extends in a westerly , direction towards, and possibly part way up, Pictc,lU Harbour (Lawrence and Neu, personal communication). With offshore (southerly) winds it will probably extend in a thin layer further offshore.

Survey 2 (Summer) - Hydrography There had been no gross observable changes wi thin Boat Harbour or the entrance since the May survey. The beaches were still stained and discoloured up to high-water mark and the effluent stream outside Boat Harbour entrance was still demarked by a precise line separating it from clean sea water beyond. To assess the difference between effluent and clean sea water, surface samples were taken at station J about I m apart, one on either side of the demarcation line. The salinity difference between these points was of the order of 2 %., and effluent concentration dropped from about 4% to about O. Samples taken in the lagoon (station D) indicate either some stratification or lack of homogeneity, a slight increase in salinity from about 1.2%0 at the surface to about 3.1%. at the bottom. The deeper samples were lighter in colour than the surface, although U. V. absorption values did not confirm this. Dissolved O2 concentrations were again zero. On this occasion, large numbers of mosquito larvae were developing in the surface layers but there were no algae visible. Samples taken below the dam again showed considerable dilution of effluent at the outfall with progressive dilution with distance from the outfall. Concen­ tration of effluent at each station decreased with depth (Fig. 8) and at the bottom in the mouth of the entrance the water was almost clear. Dissolved oxygen concentrations increased with depth but surface water O2 concentrations were lower than in May which is probably the result of higher temperatures. The samples taken across the effluent stream at Powell Point and Mackenzie Head show that the stream clings close to the shoreline and at the ollter edge is restricted to a thin layer at the surface overlying clean sea water extending inshore below it (Fig. 9, 10). For the most part, the U. V. absorption values parallel the colorimetric analysis of effluent content with the exceptions that U. V. absorption values of samples in Boat Harbour entrance give lower concentrations than those obtained by colour comparison or from calculation of freshwater concentration from salinity estimates. Off Cole Point, off Logan Point, and in the centre of Pictou Road, U. V. absorbances equivalent to effluent concentrations of H were obtained; while off Roaring Bull Point, where the samples were taken from surface and bottom near the edge of the discoloured effluent stream, U. V. absorbances were that of 0.02% effluent and pure sea water. High absorption at the wave lengths used is indicative of high organic content but, it must be stressed, is not specific for organic compounds found in the Boat Harbour effluent, and the higher absorbances on the north side of Pictou Road possibly represent organic material from another source. The lower values relative to those from colour comparison in Boat Harbour lagoon may be due to settlement of suspended particles between sampling and measurement.

Underwater Observations (Spring and Summer) The sea bed examined in May at Mackenzie Shoal consisted of small- and medium-sized boulders and appeared to be prime lobster territory. Only two lobsters (both legal-sized) were seen in 3/4 man hour under water which is considerably less than I would have expected on good lobster grounds. The area had been fished heavily for about 4 weeks and the legal stock would be reduced. The absence of sublegal and juvenile lobsters cannot be attributed to fishing and an explanation must be sought elsewhere. On comparable grounds in the Richibucto area, a similar survey could be expected to yield 10 to 20 lobsters of all sizes. Several old burrows were partly silted up and had not been recently occupied. Underwater visibility was about 2 m. The rocks were lightly covered with a flocculent detritus which is probably normal in the mouth of the estuary. There w!1s a large population of horse mussels (ModioZus modioZus) between the rocks and there was considerable coverage of Lithothamnion on rocks and mussels alike. There were numerous small starfish (Asterias vuZgaris), sea urchins (StrongyZo­ centrotus droebachiensis), barnacles (Ba Zanus crenatus), sea anemones (Metridium dianthus) and several crabs (Cancel' irroratus), cunners (Tautogo Zabrus adspersus), flounders (Pseudop Zeuronectes americanus) and sculpins (MyxocephaZus oatodecemspinosus). There were no large seaweeds. Off Logan Point the sea bed was quite comparable except that the boulders were larger and there were some rocky outcrops. The fauna was comparable with that at Mackenzie Shoal. One lobster was seen in 30 minutes under water, which is again less than would be expected. -6-

In August underwater visibility was 5-6 m at Seal Rock and about 4 m at Cole Point and Logan Point. Depths ranged from 2-5 m. The flora was similar at all three places, comprising mainly Fucus serratus with occasional patches of FurceZZaria fastigiata, Chondrus crispus, Corda fi 1.um and occasional plants of Laminaria. The animals seen were cunners, flounders, sculpins, crabs, sea urchins and periwinkles on weeds in shallow water. The weeds were in many cases well encrusted with bryozoans and the rocks were well covered with Lithothamnion which showed in places where sea urchins had browsed the flocculent detritus off the surface. In deeper areas there were numerous horse mussels, starfish (Asterias and Henricia sanguino1.enta) and also some of the polychaete Myxico 1.a. Four lobsters ranging from about 50 to 70 mm carapace length were seen at Cole Point and several recently empty burrows at Logan Point. Both these areas had the appearance of good lobster territory, and the counts are therefore lower than would be expected. The Seal Point area was not typical lobster territory and none were seen. Total dive time was about 30 minutes at each station. Several dives were made off Mackenzie Head--one just outside the demarcation line between effluent and outside water about 300 m offshore. Bottom visibility was about 0.6 m and the water was very turbid with much suspended matter. The bottom was sand. Flounders were feeding in the area disturbed by the anchor and chain and there were numerous small hermit crabs, Pagurus bernhardus, and some moon snails (Po1.inices heros). The sand extended to about 80 m from shore where the bottom changed to boulders. Visibility here was about 30 cm, the water was dis­ coloured and ambient light intensity was very low. No dives were made closer than 20 m to the shore, where visibility near the bottom was about 15 cm. Samples of Fucus, Chondrus and Purce ZZaria were collected by feeling for them. Several barnacles and peri­ winkles were seen on the rocks in the shallow water. No other animals were seen, perhaps due to the extremely poor visibility rather than the absence of other species. The seaweeds were all lightly coated with a brownish deposit which could be rubbed off with the fingers. There were only a few encrusting polyzoa, bryozoa or hydroids on the weeds and the weeds all appeared slightly paler and somewhat less robust than samples taken on the north side of Pictou Road. This may be a form of etiolation due to the low ambient light intensity under the effluent stream which, at this point, is only about 1% concentration. It '"as Impossible to make any meaningful underwater observations in more concentrated effluent and the next series of dives was made further downstream off Roaring Bull Point where the water was discoloured but the effluent concentration quite low. Underwater visibility in 5 m of water was about 1.5 m and ambient light intensity was higher than off Mackenzie Head. The bottom about 200 m offshore was sand; further inshore this gave way to outcrops of flat sand- stone ledge, the lower parts covered with the sponge, Po1.ymastia robusta. There were occasional boulders, well encrusted with tunicates, hydroids and sponges and barnacles. Laminaria was -7- the dominant weed. Many of the boulders had lobster burro~s under them and 8 lobsters ranging from 40-70 mm carapace length were seen in 30 minutes under water. This is a reasonable number for the type of bottom at this site and all the lobsters were vigorous and apparently healthy. There were numerous flounders, mostly small, sculpins, cunners, and one ocean pout (Maarozoaraes ameriaanus). Invertebrates included moon snails, scallops, hermit and rock crabs.

DISCUSSION

The spring survey was restricted to the littoral zone and, underwater, to areas outside the effluent stream. The effluent concentration studies made then match well with those made in August but oxygen concentrations in the surface waters of Boat Harbour entrance are lower in summer. Shoals of small' fish (unidentified) actively swimming in the effluent stream at the mouth of Boat Harbour entrance in August clearly indicate the absence of short-term, deleterious effects due to the reduced oxygen concentration.

The area under the effluent stream not exposed at low tide might be expected to show the most dramatic changes. Off Mackenzie Head the seaweeds differed in colour and robustness from those taken in clearer water. It is to be expected that no seaweeds would exist in the darker parts of the stream as a result of the low ambient light levels precluding photosynthesis. Similarly, the scarcity of encrusting organisms on the weeds may be indicative of low productivity within the darker parts of the effluent stream. This being so, a low population or complete absence of species from higher trophic levels might be expected. On the edges and near the end of the effluent stream, there appeared to be little or no detectable effects and underwater communi ties appeared quite normal. The lobster population is lower than experience on other lobster grounds would lead one to expect. Lobsters were seen in small numbers in clean water off Cole Point and Logan Point and on Mackenzie Shoal, and also in discoloured water close inshore under Roaring Bull Point but it seems unlikely that the effluent is causing them to leave the area as a whole. Assuming that they might not be found where effluent concentrations exceed 1%, the area 1n which such condi­ tions exist is of the order of 3 km long, ranging in width from 75 to 250 m. This is insignificant when compared w1th the total area of lobster grounds off Pictou County. D. W. McLeese has shown in laboratory experiments that lobsters did not react to a 20% solution of BKME. He concluded that in the sea the effluent would not stimulate lobsters to move away. (MS in preparation)o. -8-

THE LOBSTER FISHERY

Pictou County is part of lobster fishing district 7B with the season open from May 1 to June 30 each year and approximately 500 lobster fishermen are employed. The main feature of the fishery prior to the opening of the pulp mill was a steady decline from 2.5 million lb in 1955 to a low of 1. 06 million lb in 1967 with a minor peak around 2.2 million lb in 1959-60 (Fig. 11). The major part of the landings is from the area west of Pictou Harbour (statistical district 11) which has suffered the greatest decline (from 2 to 0.7 million lb). Landings in the area east of Pictou Harbour (statistical district 12) have been considerably smaller and steadier, varying between 0.5 and 0.3 million lb during the same period. Following the opening of the mill, the 1968 Pictou County total was up 26.5% to 1.35 million lb. Landings in 1969 in statistical district 11 were down to 716,000 lb and in district 12 to 284,000 lb. The total 1969 landings of 1 million lb were 5.7% lower than the previous low of spring 1967. In general, this area has followed the Canadian trend of declining landings in recent years. These were at a peak in excess of 50 million lb in 1955, followed by a slightly lower peak in 1960, with a systematic decline since then to a low of 36 million lb in 1967 (all figures are compiled from Department of Fisheries statistics).

CONCLUSIONS

1. Boat Harbour and its entrance are spoiled as a recreational amenity. It is possible, however, that subdivision of the lagoon and suitable aeration could render parts of it more biologically active.

2. There is clear evidence of mixing of effluent with sea water at the outfall and for the presence of a tongue of sea water extending along the bed of the entrance forming a counter current to the diluted effluent flowing seawards.

3. Dissolved oxygen- concentrations in Boat Harbour entrance are low in spring and lower in summer. There is oxygenation of the effluent beyond the mouth where there is wave action and turbulence. The low oxygen concentrations do not prevent fish from swimming up the entrance.

4. From the mouth of the harbour eastwards there was no detectable effects of effluent upon the littoral flora or fauna, although the effluent was detectable by odour and colour at least as far as Roaring Bull Point.

5. In the sublittoral zone, it appears that effluent concentra­ tions of the order of 1% or more will affect the appearance of seaweeds and reduce their epifauna. Visual observations -9-

are not possible in effluent concentrations greater than this. On the edge and near the limit of the effluent stream, there appeared to be no detectable effects. Effluent was not detected 1/4 mile offshore or beyond.

6. There was no evidence of deleterious effects upon existing lobster grounds.

7. Lobster stocks are generally low but there is no evidence that BKME has caused lobsters to leave the area.

8. Department of Fisheries statistics show a steady decline in Pictou County lobster landings from 2.5 million lb in 1955 to 1.06 million in 1967. Landings in 1968 were 26% higher than in 1967, while 1969 landings were down to 1. 0 million lb.

9. The bleached kraft mill went into full production in September 1967 and there is no evidence for attributing poor lobster catches to the effect of BKME upon the stocks.

REFERENCES

Lauzier, L. M. 1965. Drift bottle observations in , Gulf of St. Lawrence. J. Fish. Res. Bd. Canada 22: 353-368.

Scarratt, D. J. 1969. Lobster larvae off Pictou, , not affected by bleached kraft mill effluent. J. Fish. Res. Bd. Canada 26: 1931-1934.

Sprague, J. B. and D. W. McLeese. 1968. Toxicity of kraft pulp mill effluent for larval and adult lobsters and juvenile salmon. Water Res. 2: 753-760. HydrographicandbiologicalobservationsinthevicinityofBoat Harbour, PictouCountY,N.S.,May26,1969.

30 Onbeachnil,inwaterstickle- back,flounder?

3 RubblebanklOOydbelow dam,westbank Pillbugsonbeach,deadbarnacle &periwinkleshells,oldFucu8 haptera,nonewfronds

4 Mudflat200ydbelow Eelgrassroots,nonewleaves; dam, west bank dead clams? decaying in burrows

40~ :~I~:c~~s;o~~:weeds, perhlinkles 80) 3 8 Mouth of Boat Harbour 20_ 90 east bank

9 Sandy beach in cove 100) Rocky beach with barnacles, ) periwinkles,seaweeds, 10 ~:~~~nzie Head, boulder 100) isopods,amphipods,etc. ) recent set of barnacle cypris ) larvaejdiscolouredwater visible up to 2S0ydoffshore 11 Roaring Bull Point, Trace 100) Discoloured water apparent up to ledges "tmile offshore but barely detectable by colorimetric comparisonmethodjrockswith expectedfauna,flora Footnotes toTable I:

lAssumingseawaterhassalinity29.0t.;effluent1.3t..

2High02andFWcontentand low colour indicate thateffluentonlyoccasionally enters this lagoon and most FWhere is run·off from hill behind lagoon.

3LO:~~I~:~~n~~~h.O~~~hercolour here and foam, the results of onshore wind holding Table 2. Temperature and salinity at offshore sampling stations, May 27, 1969.

Station _A__ __B_ __C_ __D_ __E_ Depth Temp. Sal. Temp. Sal. Temp. Sal. Temp. Sal. Temp. Sal.

°c %. °c %. °c °c °c %.

Surface 7.8 29.3 8.3 28.1 7.7 28.8 7.7 28.8 7.6 29.9

7.6 29.3 8.1 28.1 7.6 29.3 7.8 28.8 7.5 29.9

7.6 29.3 8.1 28.1 7.3 29.3 7.5 29.3 7.3 29.9

7.6 29.3 7.2 28.7 7.1 29.3 7.4 29.3 7.1 29.9

6.8 29.8

6.6 29.8 6.5 30.4 6.8 29.3 6.8 29.9

Bottom 6.4 30.4 6.4 29.9 6.8 29.9 (depth) (3 m) (5 m) (7 m) (9 m) (6 m)

N.B. Dissolved oxygen concentrations were 100% saturation at all sample depths. Bracketed figure indicates bottom depth. Table 3. Primary observations made at Pictou, August 19-21, 1969.

pH A Station Depth Temp. S.G. °2 Colour A250 220 1969 em) °c ppm

Aug. 19 20.5 1.0175 15-18 7.28 0.950 19.9 1.0195 8 7.36 0.381 19.5 1.0215 0-2 7.82 0.072 0.169

0 21.4 1.0145 30-35 7.37 1.70 4.05 1.5 19.6 1.0195 6 7.50 0.271 0.520 3.0 19.7 1.0190 3 7.60 0.224 0.490

0 21.3 1.0150 30 7.37 1.68 4.50 1.5 20.7 1.0155 30-32 7.36 1.625 3.0 20.2 1.0160 18-20 7.35 1.179

0 24.4 0.9980 100 7.12 standard 2.25 23.4 0.9990 98-100 7.46 9.62 4.5 19.5 1.0005 70 7.45 8.54

E' 7.88 0.042 0.124

Aug. 20 18.8 1.0215 7.56 0.076 0.182 18.8 1.0215 7.93 0.040 0.122

18.7 1.0215 7.86 0.054 0.145 18.7 1.0215 7.94 0.052 0.126

18.9 1.0215 4-5 7.57 0.300 0.575 18.7 1.0215 0 7.87 0.058 0.142

0 19.1 1.0190 12-15 7.30 0.784 0.75 18.7 1.0210 1-2 7.78 0.155 0.300 1.5 18.2 1.0210 0 7.85 0.097 0.214

0* 18.0 1.0215 7.87 0.047 0.130 Ot 18.6 1.0200 7.58 0.312 0.598 1.5t 18.5 1.0205 7.94 0.040 0.119 18.6 1.0205 7.85 0.038 0.120

0 19.7 1.0210 0-1 7.88 0.078 0.180 5.5 18.5 1.0210 0 7.92 0.039 0.121

0 18.8 1.0215 7.83 0.100 0.205 4.0 18.5 1.0215 7.90 0.073 0.175

0 18.8 1.0205 0-1 7.74 0.130 0.245 1.0 18.8 1.0210 0-1 7.83 0.119 0.244 2.75 18.7 1.0215 0-1 7.86 0.097 0.210

'Clear water used for mixing standard colour series. Table 3 (cont'd.)

Station Depth Temp. S:.. G. O Colour pH Date 2 A250 A220 1969 (m) °c ppm

Aug. 20 0 0 18.3 1.0215 7.90 0.037 0.108 9.5 18.0 1.0215 7.94 0.035 0.108

Aug. 21 P 18.1 1.0215 7.92 0.109 0.215

17.5 1.0210 7.96 0.130 0.240

16.6 1.0225 7.96 0.043 0.122

17.8 1.0220 7.96 0.158 0.280

19.3 1.0200 7.92 0.080 0.189

"'Outside effluent line t Ins ide effluent line Table 4. Oxygen concentration, salinity and concentration of effluent (determined by colour, freshwater content, and U.V. absorbance) off Pictou, N.S. , August 1969.

a b C Location Sta. Depth Oxygen Colour Salinity FW C (m) % sat. % % Stations in Boat Harbour entrance Outside 45 15-18 23.7 16.8 10.5 55 8 26.2 8.7 4.0 85 0-2 28.7 0 0.4

Houth 0 12 30-35 20.1 29.5 18.9 1.5 32 6 26.1 8.4 2.7 3 75 3 25.5 10.5 2.2

Head 0 22 30 20.4 28.4 18.9 1.5 22 30-32 21.5 24.6 18.3 3 32 18-20 21.7 23.9 13.3

Lagoon 0 100 1.2 100 100.0 2.25 98-100 1.7 100 110.0 4.5 70 3.1 100 98.8

Profile off Powell Point

200 m 28.5 0.47 28.5 0.05

150 m 28.5 0.18 28.5 0.19

75 m 4.5 28.5 3.02 0 28.5 0.26

0 12·15 25.3 11.2 8.6 0.75 1-2 27.7 2.8 1.4 1.5 0 27.8 2.4 0.7

Profile off Hackenzie Head

300 m 0 0-1 28.1 1-6 0.49 5.5 0 27.8 2-4 0.05

100 m 0 28.5 0.75 "4.0 28.4 0.4.4

50 m 0 0-1 27.2 4.5 1.09 11.0 0-1 27.9 2.1 0.96 2.75 0-1 28.5 0 0.7 Table 4 (cont'd.)

a b C Location Sta. Depth Oxygen Colour Salinity FW C (m) % sat. %.

Spot locations Pictou breakwater 0.08 Off Boat Harbour outside of dark line 28.3 0.7 0.14 inside of dark line 0 26.5 7.0 3.19 1.5 27.1 4.9 0.06 Off sandy beach 27.1 4.6 0.03 Roaring Bull Pt. 0 28.3 0.4 0.02 9.5 28.3 0.7 0 Cole Point 27.5 3.1 0.85

Logan Point 29.7 1.09 Seal Rock 29.2 0.09 Fairway Buoy 28.9 1.41 Abercrombie Pt. 26.7 6.6 0.52

Superscript a Colour = effluent concentration determined colorimetric­ ally. b FW = effluent concentration from salinity determina- tion 28.5%. being regarded as standard. c C = effluent concentration by U. V. absorbance. Fi9.l. Pictou study area May 1969.

~ Seal Rk ):(R

Q LOQOnPt~MOcdonoldReef

):(p oS Pictou Road

Pictou study area August 1969. within shaded area see Fig. 7. o Sample Station. ):( Dive + Sample Station. Stations __A ----.------11 15-18 8 0-2

Colour (%)

27.7 26.2 28.7 26.1 21.5 5.5 21.7

Salinity (%0) c_~[

Oxygen (ppm)

10.5 4.0 ~ 2.7

~______....:..=..:.:::...-_..J-'---~=--

Concentrotion of Effluent (%) (from UV obsorbonces)

Fi l~. 8. Prof i 1es in Boa t lIarhour en trance. Aug. 19. 1969. SIOljons-4~.....-.---.- H __-el>------"Shore Colour(%) ~0_--...J'J,--M 4_Y

0.5 8.6 Concentrotion 1.4 of Effluent (%) 0.7 0.05

Fi ~. ~l. Prof i I es off Powell Point. }\up,ust 20, 1969. Station. --,..------.------,L Shore

0-' 5.5 M Colour (%)

28.5 27.2

Salinity (%0)

Concentration of Effluent (%)

Fig. 1U. Profiles off ~Iackenzi.e lIead. August 20, 1969. ..._-_.._--_ ...... _--_...... -_._----...... _... -... -.... -._- Statistical District No 12 (East)

'54 '56 '58 '66

Pictou County lobster landin9S 1952-69.