Taylor Henry, 8, volunteered to count horseshoe crabs along the shoreline at midnight. He said the way the males pile on top of one another reminds him of "cuddling" with his cat, Catty. At Stage ...

At Stage Harbor in Chatham, Derek Perry, the state’s horseshoe crab biologist, walks the shoreline, counting how many horseshoe crabs fall within a 25-square-meter area. It’s not an easy task, ...