. The Canadian field-naturalist. Natural history. 478 The Canadian Field-Naturalist Vol. 109 Table 1. Comparison of offshore occurrences of the Black Rockfish, S. melanops. All fish were captured with surface gill- nets or longlines, within 7 m of the surface. Distance Water Offshore Gonad Date of Standard Temperature Latitude Longitude (km) Sex Condition Capture Length (cm) (°C) Reference 50°N 145°W 1056 9 gravid; eyed embryos 5 March 1992 ° This study 45°18'N 140°56'W 1166 9 ripe and running 11 March 1992 ° This study 50°N 165°W 445 9 spent 15 February 1969 ° Dunn and
. The Canadian field-naturalist. Natural history. 478 The Canadian Field-Naturalist Vol. 109 Table 1. Comparison of offshore occurrences of the Black Rockfish, S. melanops. All fish were captured with surface gill- nets or longlines, within 7 m of the surface. Distance Water Offshore Gonad Date of Standard Temperature Latitude Longitude (km) Sex Condition Capture Length (cm) (°C) Reference 50°N 145°W 1056 9 gravid; eyed embryos 5 March 1992 ° This study 45°18'N 140°56'W 1166 9 ripe and running 11 March 1992 ° This study 50°N 165°W 445 9 spent 15 February 1969 ° Dunn and Hitz 1969 45°37'N 125°04'W 89 9 gravid 12 January 1963 Unknown 980(a) Dunn and Hitz 1969 Turner and Aro 1968 51°N 135°W 278 9 (two) gravid 13 January 1964 Unknown 7_6o,a) Dunn and Hitz 1969 Turner and Aro 1968 ^Temperature data from information recorded in data files held at the Pacific Biological Station, Nanaimo, See Turner and Aro (1968) for an overview of this data. which typically have a cm (;) stretched mesh. It is unclear whether the failure to collect males represents a differential depth distribution for the sexes or simply random chance (probability 10 m for the rest of the year. As the females contain zygotes, there is no need for males to be present at spawning. The records of surface temperature, size of fish, and gonad condition (Table 1) suggest that spawning occurs at temperatures of ca. 9°C or higher. For the. Figure 1. Photograph of second female Black Rockfish {Sebastes melanops), showing ripe and running condi- tion at Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Ottawa Field-Naturalists' Club. Ottawa, Ottawa Field-Naturalists' Club
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