Blue whale normally gives birth to a baby. But rarely delivers twins but only one calf survives as it can't tend both. Females give birth to calves every two to three years. They remain pregnant for about one year before giving birth. When born, the blue whale calf is about 23 feet (7 m) long and weighs 5,000 to 6,000 pounds (2,700 kg).
a billion
Useally one at a time.
Blue whales only give birth to one baby (calf) at a time.
Usually they have one baby at a time; twins are very rare.
200 blue whale
1
1 baby or 2
1 or rarely 2
A blue whale can feed approximately feed 50,000 people
one
501
only once