First dolphins, now whales — sea mammals in New York City are bigger than Cats! Urban nature blogger Matthew Wills caught a humpback whale frolicking off Sandy Hook, N.J., within sight of the city. (He's got some great pictures over at his blog.)

Grist thanks its sponsors. Become one.

Wills was dismayed by the floating trash in the bay, not to mention all the garbage produced by his fellow boat passengers. But on the whole, the presence of whales and dolphins is a good indicator for water quality.

Grist thanks its sponsors. Become one.