Rodents

Rats thrive around humans, for good reason: They feed off crops and garbage and readily adapt to many settings, from farms to the world’s largest cities. To control them, people often resort to poisons. But chemicals that kill rats can also harm other animals. The most commonly used poisons are called anticoagulant rodenticides. They work by interfering with blood clotting in animals that consume them. These enticingly flavored bait blocks are placed outside of buildings, in small black boxes that only rats and mice can enter. But the poison remains in the rodents’ bodies, threatening larger animals that prey on them. My colleagues and I recently reviewed studies from around the world that sought to document wild mammal carnivores’ exposure to anticoagulant rodenticides. Many animals tested in these studies were already dead; others were alive and a part of other studies. Researchers detected rodenticides in about one-third of the animals in these analyses, i...

At the far end of the Northwestern Hawaiian Islands lies Kuaihelani – also known as Midway Atoll – a small set of islands home to the world’s largest albatross colony. Over a million albatrosses return to Kuaihelani each year to breed. These seemingly pristine islands appear safe, but there’s a predator lurking among the seabirds. House mice (Mus musculus) — the same kind that may be in your residence — have started to attack and kill albatrosses, eating them alive as they sit on their nests. I’m an ecologist who’s been studying the mystery behind these murderous mice. A predator hiding in plain sight Once the site of intense warfare during World War II, Kuaihelani is now a national wildlife refuge. Without predators such as cats, rats or mongooses, Kuaihelani provides a safe haven for millions of nesting and migratory birds, including mōlī (Phoebastria immutabilis), also known as Laysan albatrosses. These seabirds, e...