EARLY LIFE HISTORY OF SAND LANCE {AMMODYTES), WITH 



EVIDENCE FOR SPAWNING OF A. DUBIUS IN 



FORTUNE BAY, NEWFOUNDLAND 



E. L Dalley and G H Winters' 



ABSTRACT 



Ichthyoplankton surveys in Fortune Bay, Newfoundland, indicate that sand lance (Ammodytes sp.) 

 larvae occur annually in Fortune Bay from February, when recently hatched yolk-sac larvae occur, 

 until July August when, it is assumed, the larvae have grown to the size of metamorphosis and have 

 taken up a demersal existence. Length-frequency data indicate the spawning season to extend from 

 December to May-June, and this extended spawning season probably accounts for the consistent 

 polymodality in length-frequency distribution of sand lance larvae from the Newfoundland area. 



Meristic development is shown to be complete by the time a length of 35-40 mm is reached and 

 analyses of meristic counts indicate that the large ( >20 mm) sand lance larvae caught in Fortune Bay 

 belonged to the offshore species Ammodytes dubius. Further, analyses of pre-anal melanophore 

 counts and oceanographic features of the area indicate that yolk-sac larvae taken in Fortune Bay in 

 February were also A. dubius. This is the first record of the occurrence and spawning oi A. dubius in 

 coastal Newfoundland waters. This finding is significant in view of the current confusion regarding 

 the appropriate taxonomy of sand lance populations in the Northwest Atlantic. 



Sand lance, Ammodytes sp., are widely dis- 

 tributed in the Northwest Atlantic from Green- 

 land south to Cape Hatteras, NC (Liem and Scott 

 1966). Although presently commercially unim- 

 portant, they hold a strategic niche as a major 

 food organism for numerous commercial fish spe- 

 cies, and Winters ( 1981, 1983) listed sand lance as 

 a prey of haddock, Atlantic cod, silver hake, yel- 

 lowtail flounder, American plaice, and Atlantic 

 salmon. They are also fed heavily upon by certain 

 large marine mammals (Overholtz and Nicolas 

 1979), and it has been postulated (Winters 1983) 

 that their importance as a prey species is en- 

 hanced during times of low capelin abundance. 



Taxonomy of the Northwest Atlantic sand 

 lance has received considerable attention 

 (Richards et al. 1963; Richards 1982; Scott 1968, 

 1972; Winters 1970). Generally two species ai-e 

 recognized in the Northwest Atlantic, i.e., Am- 

 modytes americanus (= Ammodytes hexapterus), 

 which is the deep-bodied, inshore form, and Am- 

 modytes dubius, the slender-bodied, offshore 

 form. Their taxonomy, generally, is confused by 

 the presence of two clines in their meristic char- 

 acter frequencies: one north to south cline, the 

 other inshore to offshore cline, with frequent 



'Science Branch, Department of Fisheries and Oceans, P.O. 

 Box 5667, St. John's, Newfoundland AlC 5X1, Canada. 



Manuscript accepted April 1987. 



FISHERY BULLETIN: VOL. 85, NO. 3. 1987. 



overlap in the ranges of meristic numbers (Reay 

 1970). The validity of the two species is also ques- 

 tioned due to correlations of meristic numbers 

 with environmental conditions (Scott 1972). In 

 the Newfoundland area, however, the two species 

 exhibit quite distinct meristic counts (Winters 

 1970). For the purposes of this paper we use the 

 species classification of Liem and Scott (1966). 



Winters (1970) has described the meristics and 

 morphometries of both species from the New- 

 foundland area and described A. dubius in the 

 offshore and A. americanus inshore. Winters 

 (1981, 1983) has described aspects of the biology 

 of A. dubius from the Newfoundland Grand 

 Banks. Little information exists on their early 

 life history in the Newfoundland area. Dannevig 

 (1918) provided length and distribution informa- 

 tion for 89 specimens of sand lance captured off 

 southern Newfoundland in surface and vertical 

 hauls in early summer 1915. He assigned the 

 specimens to A. tobianus (Linnaeus), a European 

 inshore species. Frost (1938) presented informa- 

 tion on the distribution of sand lance larvae 

 around Newfoundland from 1931 to 1935. No size 

 information was provided, and she assigned all 

 the specimens from both near shore and the edge 

 of the Grand Banks to A. americanus . In spite of 

 its importance as a forage fish to commercially 

 important species, no other information exists for 

 sand lance larvae from the Newfoundland area. 



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