What Is A Worm Moon And Why It Marks The Start Of Spring Season

Common names of full moons generally come from seasonal animals, colours or crops: wolf moon, pink moon, harvest moon.

The worm moon has risen. The final full moon of winter in the northern hemisphere appeared on March 25 and owes its name to Native Americans who noted winter's end by the trails of earthworms it illuminated on the newly thawed soil.

Common names of full moons generally come from seasonal animals, colours or crops: wolf moon, pink moon, harvest moon. But the worm moon may be losing its significance, as climate change leads to wetter summers and milder winters in much of the world. I've been an earthworm scientist for more than three decades, and, of late, I'm seeing signs of worms at the surface in months when they used to be inactive.

To track how the worm moon might be changing we can look at a particular earthworm species (Lumbricus terrestris, aka the dew worm, nightcrawler or lob worm) which is unusually easy to track. Also sometimes called the common earthworm, if you see a big worm in the garden, it's likely to be this species.