Estuarine Resource- Inventory Survey, Cocagne Bay Area, New Brunswick

Transcription

1 1. Environment Canada Environnement Canada Fisheries and Service des peches Marine Service et des sciences de lamer - M A Canada. Fisheries and Marine r Service. Maritimes Region. (--" Resource Development Branch. DATA RECORD SERIES MAR/D Estuarine Resource- Inventory Survey, Cocagne Bay Area, New Brunswick by W. A. England and R. S. A. Daigle Data Record Series No. MAR/D-75-7 Resource Development Branch Maritimes Region Li

2 ESTUARINE RESOURCE-INVENTORY SURVEY, COCAGNE BAY AREA, NEW BRUNSWICK W.A. ENGLAND AND R.S.A. DAIGLE SEPTEMBER, 1975 DATA RECORD SERIES NO. MAR/D-75-7 RESOURCE DEVELOPMENT BRANCH FISHERIES AND MARINE SERVICE DEPARTMENT OF THE ENVIRONMENT HALIFAX, NOVA SCOTIA

3 111 CONTENTS LIST OF ILLUSTRATIONS INTRODUCTION 1 LOCATION AND GENERAL DESCRIPTION 1 METHODS AND EQUIPMENT 2 RESULTS 2 Zone 1 2 Summary of Zone 1 3 Zone 2 3 Summary of Zone 2 4 Zone 3 5 Summary of Zone 3 6 Zone 4 6 Summary of Zone 4 7 Zone 5 7 Summary of Zone 5 8 SUMMARY AND RECOMMENDATIONS 8 Oysters 8 Quahaugs 10 Mussels 10 Clams 10 Predators 11 APPENDIX A - YIELD PER UNIT OF EFFORT, SIZE AND AGE- FREQUENCY OF OYSTERS, AS DETERMINED BY QUANTITATIVE SAMPLING, COCAGNE BAY AREA, APPENDIX B - SOFTSHELL CLAM DENSITY, YIELD PER UNIT OF EFFORT AND SIZE-FREQUENCY DISTRIBUTION, AS DETERMINED BY QUANTITATIVE SAMPLING, COCAGNE BAY AREA, APPENDIX C - YIELD PER UNIT OF EFFORT AND SIZE DISTRIBUTION OF QUAHAUGS, AS DETERMINED BY QUANTITATIVE SAMPLING, COCAGNE BAY AREA,

4 V LIST OF ILLUSTRATIONS FIG. 1. LOCATION MAP OF RESOURCE-INVENTORY SURVEY AREAS IN COCAGNE BAY AND COCAGNE RIVER, KENT COUNTY, NEW BRUNSWICK 13 FIG. 2. MAP ILLUSTRATING ZONE BOUNDARIES IN THE RESOURCE-INVENTORY SURVEY OF COCAGNE BAY AND COCAGNE RIVER 15 FIG. 3. QUAHAUG RAKE,DESIGN IN USE AT LONG ISLAND, NEW YORK, U.S.A. 17 FIG. 4. PHYSICAL CHARACTERISTICS, COCAGNE BAY AREA K5-A 19 FIG. 5. PHYSICAL CHARACTERISTICS, COCAGNE BAY AREA K5-B 21 FIG. 6. PHYSICAL CHARACTERISTICS, COCAGNE BAY AREA K5-C 23 FIG. 7. SHELLFISH DISTRIBUTION, COCAGNE BAY AREA K5-A 25 FIG. 8. SHELLFISH DISTRIBUTION, COCAGNE BAY AREA K5-B 27 FIG. 9. SHELLFISH DISTRIBUTION, COCAGNE BAY AREA K5-C 29

5 INTRODUCTION The survey of Cocagne Bay area is another in the series of estuarine resource-inventory surveys carried out in the Maritime Provinces by the Resource Development Branch, Fisheries and Marine Service, Department of the Environment. The purpose of these surveys is to obtain data on which to base programs for the management and development of the shellfish resources of the Maritime Provinces. The survey of Cocagne Bay (Figs. 1 and 2) was carried out by the authors, assisted by V.T. MacKay of the Oyster Culture Station, Ellerslie, Prince Edward Island, during August and September, LOCATION AND GENERAL DESCRIPTION Cocagne Bay is located on the Northumberland Strait shore of Kent County, New Brunswick. It is a large, shallow bay (average depth less than 14 feet at normal high tide), partially separated from Northumberland Strait by Cocagne Island. Cocagne River, the only tributary of any consequence, flows into the bay from the west, and its lower section resembles an arm of the bay rather than a river. For a distance of approximately four miles up from the bay, the river channel is fairly deep and well-defined. It then narrows and becomes little more than a large stream. The area surveyed is located between a line drawn across Cocagne River approximately one mile below the highway bridge at Notre Dame and a line extending from Cormierville Wharf to Renouard Point (Fig. 1). The area includes all the wide part of Cocagne River, Cocagne Bay and the waters surrounding Cocagne Island, and contains approximately 5,500 acres. It is slightly more than eight miles long from east to west, and is generally less than two miles wide. It is protected on the east by Cocagne Cape and Cocagne Island, making it comparatively well sheltered. Due to contamination by domestic pollution, the entire river and the extreme westerly section of the bay are closed to the taking of shellfish, except for depurating purposes (Item 6-5 of Schedule E to the New Brunswick Fishery Regulations). At the time of the survey, 25 active oyster leases, containing a total area of acres, were located in Cocagne Bay (Fig. 2).

6 2 METHODS AND EQUIPMENT Cocagne Bay was traversed in a 14-ft fibreglass boat (Boston Whaler), powered by a 25-hp outboard motor. Long wooden poles were used to test the consistency of the bottom and to locate shell beds and channels. Where wading was impossible, oyster tongs and oyster drags were used to obtain samples of oysters, mussels and starfish, and to determine the presence and density of eelgrass and other marine plants. Also, where the water was too deep to wade, the quahaug population was assessed by using a quahaug rake, similar to those used in the Long Island, United States, area (Fig. 3). The entire intertidal zone was surveyed by walking, and shellfish populations were checked by using shovels and rakes. RESULTS Maps have been prepared to show the physical characteristics of the survey area (Figs. 4-6). Quantitative sampling for oysters, clams and quahaugs was carried out and catch data were summarized (Appendices A-C, respectively). Information obtained from this sampling was used to prepare shellfish distribution maps (Figs. 7-9). It is quite evident that Cocagne Bay and Cocagne River were at one time highly productive oyster areas. As a matter of fact, Cocagne River still is. Good concentrations of oysters are evident in the channel and along the channel banks for more than three miles up from the river mouth. On the other hand, Cocagne Bay presents a very different picture. Although it contains more than 100 old shell beds, ranging from one acre down to less than one-eighth acre in size, some of them are silted over completely and all are barren. In addition to the oyster (Crassostrea virginica), the following shellfish are found in the area; soft-shell clam (Mya arenaria), quahaug (Venus mercenaria), blue mussel (Mytilus edulis), razor clam (Ensis directus) and bar clam (Spisula sozidissma). For the purpose of this discussion the area was divided into five zones (Fig. 2). Zone 1 Zone 1 consists of the Cocagne River above, or west of, the new highway bridge (Fig. 4). The river was examined for approximately three miles above the bridge, and was found to contain a rather narrow channel extending the entire length of the zone. The channel is quite deep for the first two miles above the bridge, but gradually becomes shallow in the upper section. The

7 3 area on either side of the channel consists mainly of soft mud bottom in shallow water (bare or nearly bare at extreme low tides), and is covered with a fairly heavy growth of eelgrass. Oysters of several year-classes, many of them of legal commercial size, are found in the channel and on the banks of the channel within approximately two miles of the bridge. They are quite heavily concentrated in the first 1.5 miles above the bridge but are less dense in the upper section. Quality is fairly good, although the oysters are inclined to be clustered and, therefore, rather poorly shaped. This is due, in part, to lack of cultivation, since very little oyster fishing has taken place in the area in recent years. Soft-shell clams are found in a narrow band along the shore at many locations. However, the average size of the clams is quite small and, except in a few isolated areas, the digging is very difficult. A few scattered, small mussels are found at a number of locations in this zone but nowhere in commercial quantities. The entire zone is located within a public health shellfish closure area. Therefore, shellfish taken from the area must be depurated before being placed on the market. Summary of Zone 1 Zone 1 contains approximately seven acres of ground now producing oysters in commercial quantities, all of it located in, or on the banks of, the channel. The remainder of the area is not suitable for oyster cultivation, because of its location within a public health shellfish closure area, its type of bottom and the presence of eelgrass and shallow water. It is evident that more extensive fishing in the area now producing would result in a greater production of better quality oysters. Harvesting of soft-shell clams on a commercial basis in the area is not feasible. Also, mussels are not present in commercial quantities in this zone. Oyster sampling stations 0-1 to 0-4 are located in this zone and data obtained at these stations are tabulated in Appendix A. Zone 2 Zone 2 consists of all that section of Cocagne River below the new highway bridge (Fig. 4), and extends into Cocagne Bay as far as the easterly boundary of the public health shellfish closure area (Fig. 5). The old highway bridge spans the river at Cocagne approximately one mile below the new highway bridge, and Cocagne

8 4 Wharf is located just east of the old bridge. Cote d'or Wharf is also located in this zone, and is situated close to the zone boundary on the westerly shore of the bay. The fairly deep channel in Zone 1 continues across Zone 2 and enters the bay in the vicinity of the Zone 2-3 boundary, where it ceases to be a well-defined channel. Good concentrations of oysters, mixed with mussels in the vicinity of the old bridge, exist practically all the way across the zone. Although the oysters are concentrated mainly on the channel banks, they also extend across the channel in several places. A limited area of shell-covered bottom containing mussels and oysters is located just above the old highway bridge. Mud flats between the two bridges are similar to those in Zone 1 and, in general, are not considered suitable for producing oysters. Between the old highway bridge and the easterly boundary of the zone there is an area of firm bottom on the north side of the channel and another smaller area on the south side. Several shell beds are located in the extreme easterly section of the zone; all of them are quite small, acres in size, and practically all are completely barren. Although soft-shell clams are present in a very narrow band along the shore at a number of places, the only worthwhile concentration is at the mouth of Gueguen's Brook on the westerly shore of the bay, near the easterly boundary. A few quahaugs are found in the zone, but they are very widely scattered and not present in commercial quantities. This zone is also located entirely within a public health shellfish closure area. Summary of Zone 2 By far the heaviest concentrations of oysters in the Cocagne area are located in Zone 2. An estimated acres of bottom are producing oysters or a mixture of oysters and mussels. In general, the oysters are heavily concentrated and are of practically every year-class from 1967 to Many are of legal commercial size and of fairly good quality, although they are badly clustered due to lack of cultivation by fishing. As in Zone 1, both production and quality of these oysters would likely improve if more intensively fished. In addition to the area currently producing oysters, this zone contains approximately 40 acres of bottom suitable for oyster farming. An equal amount of marginal bottom also exists, where development would probably not be practical because of its location within a public health closure area.

9 5 The 6-8 acres of barren shell beds in the eastern section of the zone could probably be brought into production with proper management. Oyster sampling stations 0-5 to 0-10 are located in this zone and the data obtained at these stations is contained in Appendix A. An area of mussels mixed with oysters, contained in an estimated 7-8 acres, is located above and below the old highway bridge. Many of the mussels are of commercial size and appear to be comparatively free of pearls. Approximately one acre, or less than half of the clam bed at the mouth of Gueguen's Brook, is located in this zone and is therefore in a closed area. Additional information regarding the clams in this bed is found in Appendix B under sampling station C-1. Zone 3 Very few quahaugs are found in this zone. This zone extends from the easterly boundary of the shellfish closure area to a line extending from Survey Monument K 21 on the westerly shore of the Bay to Cocagne Cape Wharf on the easterly shore (Fig. 5). A narrow band of firm bottom, ft wide, is located along the south shore of the zone. Similar bands of firm bottom, are also present along the eastern shore and in the northwest corner of the zone. Seaward of this firm bottom is another slightly wider band of softer bottom that is classified as marginal for oysters. The entire central section of the zone, except for a number of old shell beds, is soft mud bottom, not suitable for shellfish development. The shell beds range from one acre down to one-eighth acre in size and all are barren. The water in this zone is comparatively shallow, and in very few places does it exceed 13 ft at average high tide. Oysters in worthwhile quantities are found only on private leases, where a few lessees have relayed a limited quantity from contiminated areas. Two beds of soft-shell clams are located in this zone: one off the mouth of Gueguen's Brook, in the northwest section of the zone; and the other in Cocagne Cove, in the southeast section of the zone. Very few quahaugs or mussels are found in this zone. A fairly heavy concentration of large starfish exists in the channel, in the extreme northerly section.

10 6 Summary of Zone 3 This zone contains about acres of firm bottom that could be developed for the production of oysters. The development of an additional 100 acres or more of marginal bottom would involve a considerable risk. Part of the 8-10 acres of shell beds in the zone could no doubt be brought into production with proper management, but the beds are small and scattered, and are suitable only for small-scale development. The zone contains 14 active oyster leases, having a total area of 58.6 acres. However, almost half the total area under lease should be regarded as marginal. Detailed information on the clam beds is found in the data for clam sampling stations C-1 and C-4 (Appendix B). Very few quahaugs are found in this zone. It is quite possible, however, that a more intensive search for quahaugs in the deep water would prove fruitful. Zone 4 This zone consists of the area bounded on the south by a line extending from survey monument K 21 to Cocagne Cape Wharf and on the north by a line extending from survey monument K 21 to the old wharf on Cocagne Island, and includes the main harbour entrance (Figs. 5 and 6). A small area of firm bottom is located close to the shore of Cocagne Island, and another even smaller area is located on the western shore of the zone. This zone also contains several areas of marginal bottom where attempting to grow oysters would involve considerable risk. Oysters are practically non-existent in the zone, and the few that are present are confined to a small area in the vicinity of the old wharf on Cocagne Island. A few razor clams and bar clams are found on the large area of sand north of Cocagne Cape Wharf. Very few quahaugs or mussels are now found, although the number of empty quahaug shells in the area shows that a large population of quahaugs was present at one time. A few old shell beds are located in this zone, but all are quite barren. A fairly heavy concentration of large starfish is present in the channel at the harbour entrance.

11 -7 Summary of Zone 4 This zone contains approximately 10 acres of firm bottom that could be developed for oyster production. It contains another acres of marginal bottom where attempting to grow oysters would be rather risky. The remainder of the zone, except for a few small shell beds, has a soft mud bottom not suitable for oyster production. One oyster lease of 13 acres is located in the zone, but at least half the area has a marginal bottom. Although quahaugs are not found in worthwhile quantities, it is quite possible that a more intensive search in deep water could produce positive results. Soft-shell clams, bar clams and razor clams, although present in the zone, cannot be regarded as being in commercial quantities. Zone 5 This zone consists of that part of Cocagne Bay between Cocagne Island and the mainland, north of a line extending from survey monument K 21 to the old wharf on Cocagne Island (Figs. 5 and 6). It contains a narrow band of firm bottom along the mainland shore, from Surette Island south to the Zone 4-5 boundary. It also contains another slightly wider strip of firm bottom extending along the westerly shore of Cocagne Island, from the tip of Sandy Point to the southwest tip of the Island. This strip of firm bottom is shallow in a few places, particularly in the area just south of Sandy Point, where it is probably suitable for holding oysters only during the summer months. In addition to the narrow strip of firm bottom along the shore, the entire westerly section of the zone, from Sandy Point to the southerly zone boundary, consists of marginal bottom. Part of it is covered with a moderate to fairly heavy growth of eelgrass, and is quite shallow in places. Much of the area of marginal bottom is too soft to be developed as oyster rearing ground, although a few oysters are found at several places. However, this marginal bottom is suitable for producing quahaugs, as evidenced by the fact that quahaugs in varying quantities are found over practically the entire area. The presence of a very large number of empty quahaug shells in this area indicates a very high population in the past. A small quahaug fishery for the local market is currently pursued in this zone. Oysters are found at a number of places in this zone, but nowhere are they in really worthwhile quantities. However, there is evidence that a slight but noticeable improvement in oyster reproduction has taken place in some sections during the past 2-3 years.

12 8 Soft-shell clams are present on a narrow band along much of the mainland shore and at several places on the Cocagne Island shore. However, the average size of clams is quite small, and in many places the digging is very difficult because of the type of bottom. Clam samples were taken from the more thickly populated beds and additional information on these populations has been summarized (Appendix B). A large number of old shell beds are located in this zone, indicating it was a very productive oyster area in the past. However, these shell beds now appear to be completely barren. The zone contains 10 active leases with a combined area of 30 acres, part of which has only marginally suitable bottom. Summary of Zone 5 Zone 5 contains acres of firm bottom suitable for oyster farming. Of this, approximately 20 acres are in shallow water, and are suitable for holding oysters only during the frostfree period. An additional acres of marginal bottom are located within this zone. Part of this area could probably be developed, but it would be risky. Shell beds cover an estimated total area of acres in this zone. Many of these beds could be brought into oyster production with proper management. Although present at a number of locations, oysters are quite widely scattered and, except on a few of the leases, are not found in commercial quantities. Quahaugs, in concentrations varying from widely scattered to commercial quantities, are found over about acres. Average size of the quahaugs tends to be rather large in most places, although pockets of small ones do exist. Quantitative samples of quahaugs were taken at 13 sampling stations (Appendix C). Sampling locations are shown on shellfish distribution map No. K5-C2 (Fig. 9). Samples of soft-shell clams were taken at sampling stations C-2, C-3, C-6 and C-7 (Appendix B). Mussels, bar clams and razor clams were.not found in worthwhile quantities in this zone. Oysters SUMMARY AND RECOMMENDATIONS The Cocagne area contains between 20 and 25 acres of bottom now producing oysters, practically all of it located in Cocagne River. The area also contains a large number of old shell beds, having a combined total area of approximately 25 acres. These beds are all rather small, almost completely barren, and are located mainly in Cocagne Bay.

13 9 It is estimated that the Cocagne area contains another acres of firm bottom where oyster farming could be carried out. Forty acres of this amount are located in a public health closure area, and 25 acres of the remainder are in shallow water, where holding oysters over winter would probably be unsuccessful. This firm bottom lies mainly in a rather narrow band along the shoreline and is more suitable for small, individual leases than for large-unit development. An additional acres of marginal bottom are also present, part of which probably could be developed but would involve a certain amount of risk. Although the shell beds in the bay are almost totally barren, many of them, particularly those close to the mouth of the river, could probably be brought into production by cultivating with harrows or drags. At the present time the oyster is the most important species of shellfish in, the Cocagne area. However, the resource is far from being fully exploited, as only a small fraction of the available oysters is being harvested. There is very little evidence of any worthwhile effort having been made in recent years to promote or expand the industry. The presence of a large number of shell beds is in itself proof that the bay has been a very productive oyster area in the past but, at the present time, production is limited almost entirely to the river. Since the river and the extreme westerly sections of the Bay are contaiminated by domestic pollution, shellfish from that part of the Cocagne area must be depurated before marketing. Although 24 of the 25 active leases in Cocagne Bay have been in existence for six or more years, their "return of operations" shows that since their establishment only 566 boxes of oysters have been planted and 97 boxes harvested. This seems to be a rather feeble effort on the part of the lessees, considering the immediate availability of oysters for relaying during that period. The situation at the moment appears to be that, although a rather valuable deposit of oysters is available for relaying in Cocagne River and has been for several years, there is very little evidence of anyone having made a worthwhile effort to use this advantage. It is therefore recommended that a greater effort be made to promote the development of the oyster industry in the Cocagne area, with particular emphasis being placed on relaying oysters from the contaminated area.

14 10 Quahaugs The presence of very large quantities of quahaug shells in Cocagne Bay, particularly in the section located between the west side of Cocagne Island and the mainland, is evidence of the previous existance of large quahaug populations. At the present time, quahaugs are found in a large section of Cocagne Bay, but they are rather sparsely distributed and the average size tends to be quite large. Fishing by conventional methods produces quahaugs in quantities that are barely worthwhile commercially (Appendix C). However, the area involved is quite large (several hundred acres), and it is possible that more efficient methods of harvesting could result in a profitable fishery. It was observed during the survey that in the small area where a very limited quahaug fishery has taken place in recent years the bottom appeared to be somewhat firmer than in the surrounding area. Also, it was observed that many of the shells that had been dug from the mud while fishing quahaugs had received a very good catch of oyster spat. It is, therefore, quite possible that the benefits resulting from more extensive fishing for quahaugs would be twofold. Additional information regarding quahaugs is found in Appendix C. Mussels Approximately seven acres of mussel beds are located in the Immediate vicinity of the old highway bridge. The mussels, which in places are mixed with oysters, do not appear to have a high pearl content and many are of commercial size. However, the beds are located in a contaminated area and thus are not being exploited. Clams Although Cocagne\Bay contains a number of soft-shell clam beds ranging in size from one-quarter acre to two acres, the average size of the clams is rather small (Appendix B). This condition is probably due to overfishing in some cases and overcrowding in others. A fairly active clam fishery for private consumption takes place in Cocagne Bay, but the commercial fishery is quite limited. Cocagne River contains clams in a narrow band along the shore in many places, but difficult digging, together with the necessity for depuration of all shellfish taken from the river, discourages the development of a commercial clam fishery.

15 11 A few small patches of bar clams and razor clams are found in the vicinity of the harbour entrance, but only in very limited quantities. Predators At the present time, predators do not appear to be a serious threat to shellfish in the Cocagne area. Very few starfish are found in the river, where practically all the oysters are located. Although large starfish are found in the Cocagne Bay, particularly in the vicinity of the channel leading from the harbour entrance, they are doing very little damage, since that section does not contain commercial shellfish. However, the fact that a considerable number of large starfish are present in the Bay would make it necessary for an oyster farming operation to be prepared to deal with these predators. Moon snails were found in moderate quantities on the sand flats in the vicinity of the main harbour entrance, and they are no doubt partly responsible for the small size of the bar-clam and razor-clam populations.

16 13 Miramichi Bay Pt. Escuminac NORTHUMBERLAND COUNTY NORTHUMBERLAND STRAIT Richibucto Hbr. iohibuct KENT COUNTY Buctouche Notre-Dame Buctouche Hbr. Cocagne Hbr. Cocagne Cape Shediac Bay WESTMORLAND COUNTY Shediac FIG. 1. Location map of resource-inventory survey areas in Cocagne Bay and Cocagne River, Kent County, New Brunswick.

17 15 Cormierville Wharf km I II Sandy Point Active oyster leases Jan Northumberland Strait ZONE 5 Gueguen's Brook / Renouard Point / / 0 / ZONE 4 / / Cocagne Bay Cocagne Cape Wharf Cote d '0 Wharf Cocagne Cape Cocagne ZONE 1 River FIG. 2. Map illustrating zone boundaries in the resourceinventory survey of Cocagne Bay and Cocagne River.

18 17 Copper pipe, 11/8" O.D. co Clamp C D7 It 0 Conduit, 114" O. D. Stud, 3/8" diam. Flat iron, 1"x 1/2" 22" Flat iron,11/2"x 1,4" 1/8) Steel teeth, 3" 4%1'411' Round iron, V diam. Round iron 14" diam. FIG. 3. Quahaug rake design in use at Long Island, New York, U.S.A.

19 ,w4 FN S / '*41 : i:t., 7, ti...74,. /'/' -,%' AINO-P-AK 0 COCAGNE BAY AREA uphysical CHARACTERISTICS" FIG. 4. Physical characteristics, Cocagne Bay area K5-A.

20 FIG. 5. Physical characteristics, Cocagne Bay area K5-B. COCAGNE BAY AREA "PHYSICAL CHARACTERISTICS"

21 23 COCAGNE BAY AREA "PHYSICAL CHARACTERISTICS" 0 AIORTHUMBER LA Al D STRAIT MY TO MELT MY SWELL BED RAND Raw Esto To MALT San SCOT WO OR OM *RODE MOOT= TO MAW MORA. LIMIT TO WWI= CELSIUS SM.. WM MARKEL ROCA Eat BOW. LEASE MENET 110PLOSEWE FIG. 6. Physical characteristics, Cocagne Bay area K5-C.

22 COCAGNE BAY AREA "SHELLFISH DISTRIBUTION" ke NA N.B., K5 - A2 FIG. 7. Shellfish distribution, Cocagne Bay area K5-A.

23 FIG. 8. Shellfish distribution, Cocagne Bay area K5-B.

24 APPENDIX A YIELD PER UNIT OF EFFORT, SIZE AND AGE-FREQUENCY DISTRIBUTION OF OYSTERS, AS DETERMINED BY QUANTITATIVE SAMPLING, COCAGNE BAY AREA, 1973 (Approximate area covered by tongs in 1 dip = 3 ft2. Estimated efficiency of tongs = 60-70%.) Sampling station No. of dips with tongs No. of oysters Length 2i in. Year classes Other species or less >2* in Mussels Quahaugs Not determined Not determined

25 APPENDIX B 33 SOFTSHELL CLAM DENSITY, YIELD PER UNIT OF EFFORT AND SIZE-FREQUENCY DISTRIBUTION, AS DETERMINED BY QUANTITATIVE SAMPLING, COCAGNE BAY AREA, 1973 Density and Yield Sampling station Approx. size of bed (ac) Area sampled (yd2) Number of clams Digging time per gal (min) C C-2 * C-3 i C Not recorded' C-5 i n II 1 II C " C-7 * 'These stations did not contain legal-size clams in commercial quantities. Size- Frequency Distribution Sampling station Lengthclass (cm) Number of clams in each length-class C-1 C-2 C-3 C-4 C-5 C-6 C

26 35 APPENDIX C YIELD PER UNIT OF EFFORT AND SIZE DISTRIBUTION OF QUAHAUGS, AS DETERMINED BY QUANTITATIVE SAMPLING, COCAGNE BAY AREA, 1973 Sampling station Fishing time per gal (min) Small (<2.5 in.) Length Medium Large ( in.) (>3.5 in.) X-1 60 Not graded X X X X X X X X X X X