Harbor seals, which weigh as much as 100 pounds, are not an endangered species; in fact, their numbers have increased rapidly along the Northeast coast in recent years, even as fish stocks have dwindled. With $20,000 in rewards posted, investigators were looking into the possibility that the seals might have been slashed by frustrated commercial fishermen. But the attacks were so senselessly cruel that the motive appeared to be something more twisted than mere competition for fish. Said Sadove: “It’s the sickest thing I’ve seen in the 20 years I’ve been doing this work.”