What fantasy creatures migrate with the seasons?

[Whizbang Dustyboots]

This morning, I woke up to the honking of Canada geese visiting my neighborhood, as they do twice a year. And that got me to thinking, maybe an easy way to do a quickie one-shot adventure when not everyone showed up for regular game day would be to have the characters' current home base be visited by migratory creatures that pass through each fall and spring.

Birds migrate, Butterflies migrate. Whales and sharks migrate. In a fantasy world, what sort of interesting migratory creatures might wander through for a few days or weeks, especially ones that might be worthy of some sort of adventure?

 

[sevenbastard]

Wyverns would be fun, as would purple worms.

I'm pretty sure the second cover of the 1e Monster Manual had a red dragon attacking a Pegasus migration.

 

[Voadam]

Nomads migrate, sometimes for hunting purposes, sometimes for their livestock to continually have new foraging ground they do not overtax.

In one of my games the party came across a huge tribe of nomadic centaurs in their seasonal migration pattern.

 

[Aldarc]

Griffons, Harpies, Hippogriffs

 

[Haiku Elvis]

Bulettes - the pitch: Tremors with land sharks!

 

[Whizbang Dustyboots]

In one of my games the party came across a huge tribe of nomadic centaurs in their seasonal migration pattern.

Nomadic centaurs is very good, since they could well have various rituals when they reach different locations on their routes. So the PCs could encounter a rite of adulthood or religious ceremonies or even markets.

 

[Lidgar]

Modrons. They must be marching somewhere, right?

 

[Tonguez]

Ive used Ankhegs in the past

Also used migrating Devil Rays as an ocean encounter

Umber Hulks as a threat to Dwarf Mines

Wyverns, Dinosaurs, Gorgon bulls, Sea serpents, turtle dragons, tentacruels or any other large creature...

 

[the Jester]

I actually have an every-seven-year migration of digesters (from 3e) in one area of my campaign (and probably elsewhere, but it's only come up in the one place).

I can imagine tons of other monsters migrating, especially Beasts.

 

[GMMichael]

Modrons. They must be marching somewhere, right?

And gelatinous cubes. They move to warmer climes for winter, but no one knows if it's to find more food, or because they'll die if they freeze. The other mystery: no one has ever seen a gelatinous cube moving above ground . . .