Laboratory Reference No. 81 / 1 DFO 1liiMilifH'" "' 07018769 . MANUAL FOR IDENTIFYING LARVAL FISH OF THE MIRAM ICHI BAY , GULF OF ST . LAWRENCE BY D. B. LITTLE AND S. N. MESSIEH "TH IS IS AN I NTERNAL UNPUBLISHED REPORT. IT IS NOT TO BE CITED WITHOUT PERM ISSION OF THE AUTHOR . DISTRIBUTION IS NOT LIMITED . 11 FI SH. D1111s1. 04' Resource Branch, Fisheries Management Maritimes Fisher\eS Bedford Institute of Oceanography Biological St ation P.O. Box 1006 St. Andrews Dartmouth, Nova Scotia New Brunswick QL Canada, B 2Y 4A2 Canada, EOG 2XO 626 . 5 N6 L57 GULF FISHERIES LIBRARY FISHERIES & OC8\,~S BIBLIOTHEQUE o;:s PECHES GOLFE PfC'-IE3 ET rcEMIS N~T TO BE CITED WITHOUT PERMISSION OF AUTHOR MANUAL FOR IDENTIFYING LARVAL FISH OF THE MI-RAMICHI' BAY, GUL,F OF ST. L.AW'R~NCE by D.B. Little1 and S.N. Messieh Fisheries and Oceans Marine Fish Division Bedford Institute of Oceanography Dartmouth, N.S. 1 - on contract to Marine Fish Division -1- \ . INTRODUCTION During the spring and fall of 1979 and spring of 1980 icthyoplankton surveys were conducted in the Miramichi Bay of New Brunswick and the northern Northumberland Strait area - Gulf of St. Lawrence (Figure 1). The objective of these surveys was to determine the distribution and abundance of herring larvae, however, other species of fish larvae were also collected. Twenty-one species were identified during these collections. Due to the scarcity of references on larval fish in this area, ident­ ification of the species was not easy. The only available reference on fishes in the Miramichi Bay is by McKenzie (1959). His paper contains a checklist of the adult fish found in the area and their fisheries without reference of the larvae. Descriptions of larval fish species collected in neighbouring waters are found in a few scattered references. The species described were of the four­ beard rockling (Faber 1976a), artic and radiated shanny (Faber 1976b), capeli.n . (Templeman 1948), sculpin (Khan 1971), yellowtail flounder, american plaice (Van Guelpen 1980), and mackerel larvae (Berrien 1975). A paper by Dannevig in 1914 on "Canadian Fish Eggs and Larvae 11 contains sketches of many of the same species collected during the Miramichi surveys but did not contain des­ criptions or identifying features of these larvae. A review of published work on larval identification for Northwest Atlantic, by the U.S. Fish and Wildlife Service (Anon 1978) was available and consulted frequently. However, this publication refers to larvae collected in the Mid-Atlantic Bight, and des­ criptions given were not always congruent with those of our samples. This report is designed to aid those engaged in larval fish identification in the Miramichi Bay or nearby waters in the Gulf of St. Lawrence. The manual includes descriptions of 21 larvae and a key for their identification. It should be remembered that the descriptions and key apply to those samples ex­ amined during these surveys. As pigmentation patterns may vary with larval size, descriptions based on this character, for sizes outside the size range examined, should be taken with care. MATERIALS AND METHODS Sampling stations in the surveyed area are shown in Figure 1. At each station a step oblique tow was conducted for a duration of 12 minutes, starting as close as possible from the bottom hauling up to the surface. Sampling gear consisted of nets of two mesh sizes (.333 mm and .505 mm) mounted on a .61 meter bongo frame. Samples were immediately washed with sea water and preserved in 5% formalin. Tables 1 and 2 present location and date of fish samples used in identification as well as the size range of the larvae collected. Sorting of larvae was carried out in a gridded petri dish under a binocular microscope. Identified larvae were separated by species, counted and placed in separate labelled vials. Drawings of larvae were made to scale by the use of a drawing tube attached to the microscope. Pigmentation was of much use in ident­ ification. A description of melanophyte types is presented in Table 3. An -2- • > identification key based on the most distinguishing characteristics of species examined was constructed. A reference collection of all species collected and identified is available at the Marine Fish Division, BIO, Dartmouth, Nova Scotia. -3- ' . Key for Identifying Fish Larvae in the Miramichi Bay 1. Narrow, elongate larvae. 2 Deepened bodies with tapering tail, gut relatively short. 6 2. Anus located 3/4 - 4/5 the length of the body. 3 Anus located just beyond the midpoint of the body. 5 3. Pigment dashes on anterior half of gut run dorsally in a double row, abruptly changing at the midpoint to a ventral position, anus located 4/5 the length of body. Herring Pigment dashes ventrally in a single row along entire length of gut, anus located approximately 3/4 the length of body. 4 4. Thin thread-like larvae. Capel in Thread-like larvae, but slightly deeper. Smelt 5. Stellate melanophores on the dorsal surface of the gut; ventral surface virtually unpigmented except for a small ventro-medial strip located just behind the pectorals. Sand lance Very light pigment granules arranged along the ventro-medial surface of the gut, continuing postanally to the caudal end, few light pigment dots scattered on dorsal surface. Rock gunnel 6. With spines . 7 Without spines. 8 7. Long, heavily spined body; large alligator-like head; Alligator fish huge fan-like pectorals, heavily pigmented at the tips. Spines restricted to head region; stellate melanophores on gut. Sculpin 8. With postanal bars or bands. 9 Without postanal bar or bands. 15 9. Has 3 evenly spaced postanal bands. 10 Has postanal bar or bars. 11 10. Extension of bands into finfold; no interband pigment; vent located immediately behind the yolk sac. Witch flounder No extension of bands into finfold; scattered interband pigment may in some cases merge the bands; space between yolk sac and vent. A. Plaice 11. Pigment clustered on head. 12 Little or no pigment on head. 14 12. A single dorsal bar of pigment present about mid-body; large fan like ventral fins located below the pectorals, usually Fourbeard Pigmented. rockling -4- • j More than one postanal bar 13 13. Two evenly spaced dorsal bars, and one ventral bar; ventral bar adjacent to the posterior most dorsal bar; pigmentation light. Silver hake Two evenly spaced dorsal bars, with two corresponding ventral bars; ventral bars longer than dorsal bars. Cod 14. A single, postanal dorso-ventral pair of bars located midway between vent and caudal end; bars may appear as large stellate melanophores; single stellate melanophore situated just behind the head, and ventrally near the caudal end; gut pigmentation is mainly dorsal with a small ventral spot near the vent. Cunner Six pigment bars, four ventral and two dorsal; the two dorsal bars are located adjacent to the second and third ventral bars; stellate melanophores on the dorsal surface of the gut with a pigment on the midline of the body. Yellowtail flounder 15. Stout, deep gut. 16 Na ~ row more elongate gut. 20 16. Adsence of any dorsal gut pigment; pigmentation is extirely ventral along the gut and body contour. Winter flounder Presence of dorsal gut pigment. 17 17. Presence of stellate melanophores on the posterior side of the pectoral fins. Seas nail Absence of pigment on pectoral fins. 18. Absence of pigment on head and tail region; scattered melanophores at mid-body only. Windowpane flounder Presence of pigment on head and tail region. 19 19 . Pigmentation heavy on top of head and along dorsal surface of gut. Mackerel Pigmentation sparse on head and dorsal surface of the gut. Silverside 20. Postanal pigment consists of mid-lateral melanophores regularly arranged, in a series of dashes, between the myomeres of the body; in larger specimens a double row of melanophores may be seen on the bodies dorsal contour. Arctic shan Postanal pigment has no regular arrangement; a single large mid­ ventral stellate melanophore present on the anterior most half of the gut. Radiated shanny -5- ' ' Acknowledgments ?everal people contributed to the sampling and sorting of the collection used for this identification. This study was conducted as part of the Miramichi Bay Project for which Marilyn Marley, Leslie Demal, Robert Pottle, Paul MacPherson and Dave Moore carried out most of the field work. Randy Losier sorted the 1979 collection, while Doug Markle and Lou Van Guelpen, of the Huntsman Marine Laboratory, St. Andrews, N.B. were occasionally con­ sulted for checking the identification. The figures are drawn by Peggy Mccalla and the text typed by Donna King. -6- . ' References Anon. 1978. Development of Fishes of the Mid-Atlantic Bight. An Atlas of egg, larval and juvenile stages. vol I-IV. Fish and Wildlife Service, U.S. Department of the Interior. Berrien, P. 1975. A Description of Atlantic Mackerel, Scomber Scombrus, Eggs and Early Larvae. Fishery Bulletin. 73 ( 1): 186-192. Bigelow and Schroeder. 1953. Fishes· of the Gulf of Maine. Fishery Bulletin No. 53. Fish. Bull. of the U.S. Fish and Wildlife Service. Dannevig, A. 1919. Fish eggs and larvae, p. 1-80. In J. Hjort Canadian fisheries expedition, 1914-15, in the Gulf of St. Lawrence and Atlantic waters of Canada. Dept. Nav. Serv. Can., King's Printer, Ottawa, Ont. Faber, D. 1976(a). Hyponeustonic Fish Larvae in the Northumberland Strait During Summer 1962. J.F.R.B. Canada 33(6): 1167-1174. Faber, D. 1976(b) . Identification of Four Northern Blennioid Fish Larvae in the Canadian Atlantic Ocean (Stichaeidae, Lumpenidae). J.F.R.B. Canada 33 (8): 1798-1802. Khan, N. 1971. Comparative morphology and ecology of the pelagic larvae of nine Cottidae of the northwest Atlantic and St.