This year, a 25-year-old Wisconsin program designed to revive and conserve the state’s population of trumpeter swans was officially ended. It wasn’t because of budget cuts or political interference, but simply and happily because the program had been successful, and achieved its goals. In 1987, when the recovery plan began, the trumpeter swans had nearly been wiped out completely. But a quarter century of capturing, tagging and protecting the swans has recovered the population to a degree that could be considered relatively robust, from no swans in 1987 to about 1,500 in 2012. The birds were removed from Wisconsin’s endangered and threatened species list three years ago. This year, biologists found 214 nesting pairs of swans. Those pair produced 373 offspring. That’s what a successful conservation effort looks like.