Officials are conducting tests off the northern coast of New Zealand’s South Island — one of the world’s most well-known feeding grounds for whales, dolphins, and seals — after a trailer filled with 18 tons of deadly rat poison crashed and fell into the sea. Dead fish and eels have already washed up along the coastline. The country’s Department of Conservation said smaller animals, like birds, may be more at risk than whales and dolphins because the larger animals would have to eat a heck of a lot of the rat poison to be harmed.