By Daniel Francis and Gil Hewlett. Harbour Publishing, 280 pp, $34.95, hardcover

If you're looking for the definitive book on Orcinus orca, more commonly known as the killer whale, this isn't it–and it may be some time before that volume arrives. Despite their relatively recent elevation to iconic status, the orcas of the Pacific Northwest are still a mysterious species, and until some basic facts about their habits are clarified, they will remain a subject of both lay and scientific speculation.

Operation Orca

The biggest mystery is where they spend the winter months. Once the salmon runs that sustain them through the summer and fall tail off, B.C.'s resident killer whales vanish–likely out to sea, but no one knows for sure. Encyclopedia of British Columbia editor Daniel Francis and former Vancouver Aquarium assistant director of special projects Gil Hewlett have not solved that riddle, but with Operation Orca: Springer, Luna and the Struggle to Save West Coast Killer Whales they've provided a good introduction to the largest member of the dolphin family, and a useful guide to human/orca interaction in an increasingly crowded marine environment.

As their focus, Francis and Hewlett have seized on a success story and a tragedy, each involving an abandoned infant orca. Springer, found emaciated and ill in Puget Sound in November 2001, was reintroduced to her pod a year later, and now appears to be thriving. Luna, who arrived alone in Nootka Sound at around the same time Springer was starving south of the border, was physically healthy, but developed a dangerous passion for various man-made craft, including fishing boats, kayaks, and seaplanes. After much debate, and an elaborate but unsuccessful relocation attempt, Luna got too close to a tugboat's propeller and suffered death by misadventure on March 10, 2006.

The authors offer a dispassionate chronology of each animal's life, and of human attitudes toward killer whales. These range from the tendency in the 1950s to shoot them on sight to Mowachaht/Muchalaht chief Mike Maquinna's belief that Luna was the reincarnation of his late father–although whether Maquinna's subversion of the rescue process contributed to the young whale's death is not something Francis and Hewlett care to judge. Their hands-off approach to this and other controversial issues makes Operation Orca a somewhat tepid read–Farley Mowat's Sea of Slaughter it isn't, but it's enlightening nonetheless.