A new study has uncovered evidence that a giant marine reptile from the Early Jurassic period used stealth to hunt its prey in deep or dark waters—much like owls on land today.

A beachgoer found more than 250 huge dead spider crabs washed up on the shore after heading down for an evening stroll. Samuel Lacey, 22, said the trail of crustaceans went on for as far as he could ...