China yesterday announced plans to release giant pandas born and raised in captivity into the wild in an effort to boost the population of the endangered species. Under a pilot program to be launched in 2005, two to three giant pandas are expected to be released each year, the first such releases ever attempted. Only some 1,000 pandas remain in the world, 100 of them in captivity. In other heartening charismatic megafauna news, southern right whales, which were hunted to the brink of extinction earlier this century, are making a comeback off the Argentine coast, according to an Argentine scientist. The number of southern right whales is now estimated at 7,000 — not great compared to 100,000 at the turn of the century, but the population is growing by 6.8 percent a year, according to a new survey.