Figure 3
Monthly variation of ovary components. Monthly values (mean ± SE) of relative total length-based stagei-specific oocyte number (relative TL-based NOi) and volume fraction of different elements in the ovary of hake from the Galician shelf from December 2011 to November 2012. (A) Previtellogenic oocyte stages PVO1, PVO2 and PVO3; (B) Previtellogenic oocyte stages PVO4a and PVO4b; (C) Previtellogenic oocyte stage PVO4c and cortical alveoli oocyte stage CAO; (D) Vitellogenic oocyte stages EVTO (early) and VTO (medium and late); (E) Amount (volume fraction) of blood vessels (blood) and postovulatory follicles (POF); (F) Amount (volume fraction) of early-α (Eα), late-α (Lα) and β atresia. The brown-shaded area corresponds to the mean monthly sea water temperature from 50 to 350 m depth, at 43.5°N 9.5°W, while the blue shaded area shows upwelling events occurring, according to standard definition, when the upwelling index is above zero. The dashed red line shows monthly mean day length, and the dotted grey line marks winter and summer solstice. Spawning activity (at the top of each panel) is given in relation to spawning fraction (SF): 30–50, 10–30 and <10%, in dark, medium and light purple, respectively.
