As the human population expands and land use intensifies, species of all kinds are disappearing, and each extinction brings the loss of aesthetic value, an irreplaceable role in the ecosystem, and untold medical and scientific potential. Habitat destruction is the main cause of extinction today, and migratory species need suitable habitat at summer breeding sites, winter residences, and resting places along migration routes. Because of its location, many migratory species depend on New Jersey’s coastal habitats as places to stop and rest, and for some this is their only stop. Sea turtles migrate near New Jersey to use its plentiful food source, but litter and pollution in coastal waters threaten their survival. New Jersey’s coastal habitats are also crucial for more than 50,000 raptors concentrated at the Cape May Peninsula as they migrate southward along the Atlantic Coast. Horseshoe crabs are used in many ways for modern medicine, yet development on sunny beaches reduces their spawning areas and they are harvested for bait. Destruction of tropical rain forests reduces the winter habitat and population size of New Jersey’s eastern kingbird and the Cape May warbler. Many marine mammals, including occasional humpback whales, use New Jersey’s Atlantic and bay waters, and ocean water quality is important to their survival. As other habitats have declined, seal populations have recovered and migrate to New Jersey to escape the severe cold of the Arctic winter, while proper boating practices can minimize injuries to seals. To slow extinction, people must recognize that organisms depend on one another and are affected by human populations, and must protect the resources species need for summer and winter habitat and along migration routes.