After a gestation period that lasts nearly a year, the female blue whale gives birth to a single calf on her return to the ...

to give birth. By the time blue whale calves are seven months old, they are already 52 feet long and have stopped associating with their mothers. However, the high pregnancy rates of 33 to 50 ...

Thousands of blue whales roam the oceans and the giant mammals give birth every two to three years. But the births are very stealthy, with calves rarely sighted. Given pregnancy rates as high as ...

And sightings of calves are remarkably rare, falling far below what should be expected based on pregnancy rates ... missing calves: blue whales produce calves, or give birth, shortly after ...