New Caledonian crows are one of the most industrious species on the planet. They've been known to build and utilize a range of tools. The more scientists watch these birds, the more the crows reveal themselves as nature's MacGyver.

Most recently, researchers witnessed New Caledonian crows fashioning hook-like tools out of twigs and using them to fish insects out of the insides of trees. It's the first time the behavior has been seen in the wild.

Researchers detailed their discovery in a new paper, published this week in the journal Biology Letters.

The revelation was made possible by the "crow cam," a small remote camera installed on the birds' tails. The cameras offer a shot up the length of the birds as they go about their business.

Most observations of New Caledonian crows happen in captivity. The birds are rather shy in the wild. The crow cams, however, have finally offered biologists a chance to see what's happening out in the natural world.

In addition to securing video of hook-making, scientists were able to begin to get a better sense of the crows' day-to-day activities. The cameras naturally fell off the crows after a couple days, allowing researchers to retrieve the devices and review the footage.

As the crows are discovered using more and more tools, each revelation becomes a bit less exciting. But the research team -- a combination of scientists from St. Andrews and Exeter universities -- is after answers to larger questions.

Scientists want to know why New Caledonian crows are so inventive. What drives them to make so many tools?

As researchers use daily video footage to plot the birds' use of time -- piecing together the species' "time budget," as they call it -- they hope to better understand the crows and their creativity.

The videos show that crows spend only about 3 percent of their time making and using tools.

"Every now and then, they suddenly switch into tool use - in the very same trees, in a very similar foraging context," senior study author Christian Rutz, a biologist at St. Andrews, told the BBC. "We don't understand what is happening there."