of the amphipods and ostracods {Euphilomedes) are seasonal; ovigerous 

 females are present to some extent all year but peaks of relative abun- 

 dance occur early in the year (Table 6) . 



Three species of ostracods, E. aaraharodonta , E. longiseta, and 

 E. oblonga, were predominantly represented by females and juveniles. 

 Females of this genus swarm in the water column to mate, chew off the 

 ends of the bristles on their swimming antennae, and spend the rest of 

 their lives on the bottom. They brood their eggs mostly through winter 

 to late spring (Table 6); an influx of juveniles occurs later in spring. 

 The males are strong swimmers but they die soon after mating (Kornicker, 

 personal communication) , which probably accounts for their low abundance 

 in the samples. 



The peaks of relative abundance of reproductive females of 

 Eohaustorius senci-llus were followed by peaks of juveniles in the next 

 sampling period (Fig. 8) . There was a predominance of reproductive 

 females in the 2.5- to 3-millimeter size range; few were larger. This 

 suggests that the females breed once and die. Paraphoxus daboius and 

 P. epistomus seem to follow a similar pattern to that of E. senaillus 

 but later in the year (Fig. 8). 



Relative abundance of reproductive females was highest in March, fol- 

 lowed in the next sampling period by peaks of juveniles. Since amphipods 

 brood their young which are burrowers with relatively immobile females, 

 an influx of juveniles from another population is not likely. Males are 

 active swimmers and generally more mobile than females. This may be part- 

 ly the reason for the 1:20 ratio of males to females. Fecundity is dif- 

 ficult to estimate because eggs are usually lost from the females marsupium 

 (egg pouch) during collection. Larger females carry more eggs than the 

 smaller females. Paraphoxus epistomus , 5 millimeters long, carry 18 eggs; 

 the smaller females, 3.5 to 4 millimeters long, carry 7 to 12 eggs. 

 Paraphoxiis daboius, 3 millimeters long, carry 8 eggs. The fairly distinct 

 peak of reproductive females with a small variation in their sizes (most 

 P. epistomus are 3.5 to 4 millimeters; most P. daboius, 3 to 3.5 milli- 

 meters). The low occurrence of larger females indicate that they pro- 

 bably breed only once. 



The main influx of polychaete juveniles occurred in the fall and 

 spring; the main influx of Crustacea occurred in the spring. Distinct 

 winter reproductive activity was apparent for certain species, but settl- 

 ing of bivalves was more sporadic. Polychaetes are more flexible in their 

 reproductive strategies than crustaceans or mollusks. A single species 

 which will often occur over a large geographical range, may be capable of 

 brooding young in higher latitudes and producing pelagic larvae in warmer 

 seas . 



Many of the polychaetes in the study area are found in deeper parts 

 of the Monterey Bay (Hartman, 1963; Hodgson and Nybakken, 1973), and 

 along the coast of southern California (Allan Hancock Foundation, 1965) 

 and Washington (Lie and Kisher, 1970). In contrast, most of the shallow 



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