Following a deadly explosion in a Welsh coal mine in 1896, an engineer called John Haldane invented a type of bird cage that allowed canaries to accompany miners into the depths.

Canaries are one of the most popular species because of their beautiful vibrant appearance and distinctive song. However, these little birds are trickier to care for than some people expect.

With common bird populations on the decline, these birds are “the canary in the coal mine,” said Ken Rosenberg, ... The species' appearance is among the most variable in North America.

Now it turns out the species was also misidentified, and it is actually the largest canary on the planet, 50 per cent heavier than the next largest species. Although it is small for a bird, being ...