J19, J36 and J37 are mothers-to-be who represent hope for a critically endangered species -- killer whales that frequent waters off the coast of British Columbia. Only 74 southern resident orcas remain, down from more than 90 in the 1970s, and they are considered endangered by both Canada and the US. Researchers are hopeful but caution that miscarriages and neonatal mortality can be high. In 2018, J35 carried her stillborn calf for more than two weeks, although two years later, she gave birth to a healthy baby. Southern resident orcas are distinct from northern resident populations and transient orcas.