STEVENSON and PIERCE: PANDALUS MONTAGUI AND DICHELOPANDALUS LEPTOCERUS 



caught in November-December 1980 (Table 3), 

 although a few remained in January and March. It 

 was therefore apparent that most eggs hatched dur- 

 ing a relatively short period of time in late December 

 and early January. Although only the larger size 

 group was carrying eggs (Fig. 2D), the presence of a 



were reported for the same populations as late 

 February through April with peak activity in April. 

 According to Couture and Trudel (1969b), ovigerous 

 females were observed in Grand-Rivifere, Quebec, 

 beginning in July and accounted for the greatest 

 percentage of the population in October (no samples 



Table 3.— Percent total number of male and female Dichelopandalus leptocerus 

 collected at all locations and depths in Penobscot Bay during five sampling 

 periods in 1980-81. (Females are categorized by reproductive stage.) 



few Stage II non-ovigerous females in roughly the 

 same size range (Fig. 2C) indicated that some 

 females produced eggs a year earlier as well. It could 

 not be determined from the samples collected during 

 this study whether the younger females spawned 

 earlier or later than the older group. The fact that so 

 few Stage II females were captured in the Bay at any 

 time of year indicated that most of the spawning 

 population was made up of first time spawners. 

 Ovigerous females were collected at all depths and in 

 all areas (Tables 4, 5), but made up a greater percent- 

 age of the catch at moderate depths in area 2. 



Nearly all of the ovigerous female P. montagui 

 were collected in November-December and late 

 January (Table 6); the fact that 50% of the females in 

 late January were still ovigerous suggests that eggs 

 hatched over a more prolonged period then was true 

 for D. leptocerus, possibly from November at least 

 through February. Females belonging to two North 

 Sea P. montagui populations were reported to carry 

 eggs primarily between November and February 

 (Mistakidis 1957; Allen 1963), although ovigerous 

 females were observed from mid-October to April in 

 the Thames estuary by Mistakidis. Hatching times 



*Since no internal sexual characteristics (such as oocyte develop- 

 ment) were examined in this study, the breeding season was defined 

 as the period of time when ovigerous females were observed and 

 sizes (ages) at maturity as the sizes (ages) when females produce 

 eggs. No comparable information for males (i.e., mating times or 

 sizes (ages) at maturity) was available. As used in this paper, the 

 breeding season was, strictly speaking, the period of time between 

 spawning and hatching when eggs were incubated. 



Table 4.— Percent total number of male and female Dichelo- 

 pandalus leptocerus collected at all depths and times of year 

 in four areas in Penobscot Bay during 1980-81. (Females are 

 categorized by reproductive stage.) 



Table 5.— Percent total number of male and female Dichelo- 

 pandalus leptocerus collected in all areas and times of year 

 by depth range in Penobscot Bay during 1980-81. (Females 

 are categorized by reproductive stage.) 



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