Forget purportedly disease-ridden pigeons or the supposedly overpopulous and dirty Canada Goose — a new feathered menace has taken the title of Most Hated Bird in the US, according to ALL OUTDOORS. Investigators are trying to discover who is behind a pair of recent massacres of hundreds of cormorants, fish-eating birds that are protected by federal law.The likeliest suspects: irate fishermen. The cormorant population has exploded since the 1970s, thanks largely to decreasing levels of such toxic chemicals as DDT in US waters. As their numbers have grown, the birds have taken a heavy toll on fish populations — gobbling up about $20 million worth of farmed fish annually. “I don’t know how much more pressure the fish here can take,” says one Oregon fisherman.

 The study was done by Stephanie Riegg Cellini and Nicholas Turner, and as usual, there are some caveats. Some of the negative effect may be driven by unreported tip income. The study ended in 2008, which means it might be picking up the first bits of the Great Recession. And it’s hard to infer causality: it’s almost certainly the case that better students enroll in community college programs in the first place.All that said, however, the results are pretty stunning. Once you take into account the debt load from attending for-profit schools, virtually no one benefits. Even graduates probably never make up for the cost of the program.

With rare exceptions, there are three lessons here. First: Just don’t attend a for-profit vocational school. If you can’t attend a community college, skip the whole thing. Second: At the very least, don’t do it unless you’re absolutely, 100 percent sure you’re going to finish. If you drop out, you’ll most likely end up with a bunch of debt and a lower income than you had going in. Third: Don’t even think about going to a for-profit school to get a certificate in therapeutic services. That’s the biggest killer out there.