Northern fin whale
The northern fin whale ("Balaenoptera physalus physalus") is a subspecies of fin whale that lives in the North Atlantic Ocean and North Pacific Ocean. It has been proposed that the northern Pacific population represents a separate subspecies, "B. p. velifera". At least one other subspecies of fin whale, the southern fin whale ("B. p. quoyi"), exists in the southern hemisphere. Size. Northern fin whales are smaller than their southern hemisphere counterparts, with adult males averaging and adult females . Maximum reported figures are for males and for females in the North Pacific, while the longest reliably measured were  and — all were caught off California, the former in the 1920s and the latter in the 1960s. At sexual maturity, males average in the North Atlantic and in the North Pacific, while females average in the North Atlantic and in the North Pacific. At birth, calves are in the North Pacific. Reproduction. Because of the opposing seasons in each hemisphere, "B. p. physalus" breeds at a different time of the year than "B. p. quoyi". Peak conception for "B. p. physalus" is December–January, while peak birthing is in November–December — in both the North Atlantic and North Pacific. Northern