Search results
Results from the WOW.Com Content Network
A typical precocial mammal has a gestation period almost four times longer than a typical altricial mammal of the same body size. [20] Precocial mammal species generally have greater adult body weights than altricial mammals as precocial mammals have markedly longer gestation periods than altricial mammals. [21]
Like humans, female whales typically deliver a single offspring. Whales have a typical gestation period of 12 months. Once born, the absolute dependency of the calf upon the mother lasts from one to two years. Sexual maturity is achieved at around seven to ten years of age.
The gestation period for gray whales is approximately 13 1 ⁄ 2 months, with females giving birth every one to three years. [91] [94] In the latter half of the pregnancy, the fetus experiences a rapid growth in length and mass. Similar to the narrow breeding season, most calves are born within a six-week time period in mid January. [91]
Calves are approximately 1 short ton (0.91 t; 0.89 long tons) in weight and 4–6 m (13–20 ft) in length at birth following a gestation period of 1 year. The right whale grows rapidly in its first year, typically doubling in length.
As the gestation period for right whales is a year long, researchers believe that a lack of food in the whales' summer feeding grounds in the Bay of Fundy during the summer of 2010 may be linked to the poor season in 2012. [116]
Reproduction can begin when a whale is 10 to 15 years old. The gestation period is 13–14 months with females producing a calf once every three to four years. [28] Lactation typically lasts about a year. To survive in the cold water immediately after birth, calves are born with a thick layer of blubber. Within 30 minutes of birth, bowhead ...
A single calf is born after a gestation period of one year, about 1 short ton (0.91 t) in weight and 4–6 m (13–20 ft) in length. [36] The calf usually remains with its mother during the first year of its life, during which time it will double in length. [5] Southern right whales have been observed nursing unrelated orphans on occasions. [37]
For long-finned pilot whales, gestation lasts 12–16 months, and short-finned pilot whales have a 15-month gestation period. [3] The calf nurses for 36–42 months, allowing for extensive mother-calf bonds. [3] Young pilot whales will take milk until as old as 13–15 years of age.