Mount

Mountable Creatures
Since the update "Riders of the Dragoturkey", you can mount a Dragoturkey. Like the Ginger Dragoturkey (orange-ish), Almond Dragoturkey (white/cream-colored), Golden Dragoturkey (gold, duh), or a cross-breed of these (verified as being black).

However, the wild Dragoturkeys that you capture yourself cannot be mounted. You must breed them (a male and a female, of course) in a Paddock. The Dragoturkeys that are born from this breeding will not be wild, and you will be able to mount them.

Method of capture
Complete the Koolich Dungeon (level 100+ GREATLY recommended). You must have 50 Kaliptus Leaves and 50 Kaliptus Flowers that you exchange at the end of the dungeon for a spell. The spell is named Mount Taming and it works just like Souls Seek, but instead of using soul stones, you use fisherman nets.

(Are there other nets and such? Like some soulstones have a higher chance of catching the monster than others?)

Breeding
Once you have 2, (female and male) you must bring their stamina and love up to a certain point. This must be 7.500 each for both stats. If the breeding succeeds, you'll get a female Dragoturkey that is ready to lay a egg. Take her to a public Paddock, and soon a baby Dragoturkey will appear.

After the baby Dragoturkey grows, you can mount it.

Find more information in the entry for Breeder.