Porter: Temporal and spatial distribution and abundance of eggs and larvae of Hippoglossoides elassodon 



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reared in the laboratory iS. Porter, unpubl. data). In the 

 laboratory, flathead sole larvae hatch with pigmented 

 eyes, three tail pigment bands, and an open mouth (S. 

 Porter, unpubl. data). Flathead sole larvae that were 

 collected from MOCNESS tows and that did not have 

 these features were classified as embryos (it was sus- 

 pected that handling during collection may have caused 

 some of the late stage eggs to prematurely hatch), and 

 their lengths were not included in the weighted mean 

 depth. For eggs and larvae, a weighted mean depth was 

 calculated for each stage or size category, and depths 

 were compared by using ANOVA and the Tukey HSD 

 multiple comparison test. 



Results 

 Eggs 



Geographic distribution and abundance Eggs were col- 

 lected as early as March but in small numbers (Figs. 2 

 and 3A). Most spawning began from early to mid-April 



(Fig. 3B) near the Kenai Peninsula and then progressed 

 with time southwest into Shelikof Strait and along the 

 Alaska Peninsula. There are two main areas where peak 

 spawning (from early to mid-May) occurred: Shelikof 

 Strait and between the Shumagin Islands and Unimak 

 Island (Fig. 3C). In June, spawning generally declined in 

 these areas and was most intense around Kodiak Island 

 (3D). Eggs were collected as late as July (one station in 

 1978, on the eastern side of Kodiak Island). 



Vertical distribution There were similar trends in the 

 vertical distribution of eggs among tows (Fig. 4). Abun- 

 dance peaked at about 20 to 35 m below the surface, 

 decreased at greater depth, and then slightly increased 

 below 125 m. Because the trend of the catches of the 

 tows were similar, we were able to increase sample size 

 in the depth intervals by pooling data from similar 

 depth intervals for further analyses. Eggs were pelagic 

 and most abundant near the surface (mean depth 43 

 ±10 m) and at the deep sampling depths (mean depth 

 149 ±6 m); abundance was low in mid-water (Fig. 4). 

 Late-stage eggs (stages 16-21) dominated the depths of 



