SIZE. These characteristic creatures are often 6,000 to 8,000 pounds and access to monitor the fetus during development is difficult. There have been no successful caesarean sections performed and manipulation of the fetus in the birth canal is almost impossible. Isa, at the time of Jennie's birth, was about 30 years old. In the final stages of her pregnancy, the size of her first calf made it difficult for her to stand and move around much. During 1998 Isa remained at the Ark where she spent the last few weeks with the constant companionship of Libby, another elephant from the herd and her human handler.