For a long time, I rolled my eyes at crows. They were just big black birds that screeched and cawed and messed with other birds' nests. But now I know better.
Crows are smart in lots of ways, with problem-solving skills that rival those of a young child (see my earlier post). One example of their smarts is their use of tools.
Almost anything can be a tool in a crow's beak. They even take advantage of cars, dropping hard-to-crack nuts at strategic spots on roads. Cars roll over the nuts, popping them open and saving the crow a lot of work.
New Caledonian crows are the only animal (besides us people) that are known to make hooks in the wild. They pull off a thin branch, then remove small bits of wood near the the joint that had connected the branch to the tree or bush. The resulting hook can then be used to forage for bugs.
In experiments, these crows quickly and instinctively fashion hooks out of wire to do things like lift a tiny pail of meat from a clear plastic tube. In one example, two crows were presented with a hooked wire and a straight wire. One crow immediately grabbed the hooked wire, which was needed to get a tiny pail with food from a tube. But then the second crow bent the straight wire, making a hook to get the food. Neither crow had seen wire before.
New Caledonian crows can also use tools to get other tools, completing complex series of tasks to get to their final goal. In the video below, a crow completes eight distinct steps to get to his treat.
I'm thinking about conducting my own unscientific experiment at my home. Maybe I'll set up a platform with hard-to-get food and a few thin wires. If I can get a few crows to stop by, I'll sit back and watch what they do. The crows around here aren't quite as clever as those New Caledonian crows. But they're still smart. And they might just teach me something in the process.
dlnr.hawaii.gov | openi.nlm.nih.gov | youtube.com | popsci.com | Tool bending in New Caledonian crows (Rutz, Sugasaw, et al.): rsos.royalsocietypublishing.org