Animals keep leaving the pens?

[Lycan]

Is there a way to prevent animals leaving their pen? I've build walls and a roof around them with a long hallway with two doors and yet animals keep walking out, opening the doors and wandering away into the map forcing my dwarves to constantly stop their work and go grab the animals to re-pen them. Is there a way to prevent this beyond simply walling them up entirely?

[Morkonan]

If the pastures are too small for the animals they contain, they may start fighting and animals will flee from conflicts/fights. If they're attacked by hostiles, they'll flee as well. Hunters getting into combat with their wild targets might cause animals to flee, too, if it's near a pasture.

Added: I think a Dorf's personal Pet may also try to go visit their owner, or vice-versa. I've got a goose that seems to ignore pasture orders and I find him wandering the Fortress pretty frequently. So, I just assume that's why he's doing it. :)

Check the animals to see why they are moving outside of their pasture, if you can. Check their thoughts to see what may have happened to them.

Other than building a wall around the pasture, there's not a lot you can do. You have to solve for the issues that make them leave a pasture.

(Just checking - You did create a "Pasture" zone for them, right? They're assigned to that Pasture? Also - Only certain animals, "Grazers", need a pasture in order to eat/survive. Of those that do not, birds need a Nesting Box in a Pasture zone to lay eggs/breed.)

[Lycan]

Originally posted by Morkonan:

If the pastures are too small for the animals they contain, they may start fighting and animals will flee from conflicts/fights. If they're attacked by hostiles, they'll flee as well. Hunters getting into combat with their wild targets might cause animals to flee, too, if it's near a pasture.

Added: I think a Dorf's personal Pet may also try to go visit their owner, or vice-versa. I've got a goose that seems to ignore pasture orders and I find him wandering the Fortress pretty frequently. So, I just assume that's why he's doing it. :)

Check the animals to see why they are moving outside of their pasture, if you can. Check their thoughts to see what may have happened to them.

Other than building a wall around the pasture, there's not a lot you can do. You have to solve for the issues that make them leave a pasture.

(Just checking - You did create a "Pasture" zone for them, right? They're assigned to that Pasture? Also - Only certain animals, "Grazers", need a pasture in order to eat/survive. Of those that do not, birds need a Nesting Box in a Pasture zone to lay eggs/breed.)

yeah I've made a pasture zone, maybe it's just too small, I'll try enlarging it by a big margin. Thank you for answering.

[Morkonan]

Originally posted by Lycan:

..
yeah I've made a pasture zone, maybe it's just too small, I'll try enlarging it by a big margin. Thank you for answering.

YW! It's probably the pasture size and there's no easy way to know what the sufficient space would be for a mixed population of grazing animals. You'll just have to guess and tweak as needed. You can, however, look up the space requirements on the wiki (Pastures, IIRC) but it's really a pain to calc and eyeballing it isn't easy, either. :)

[Erei]

I know cats like to wander all the time.
Which, to be fair, sound like something totally normal.

[Diarmuhnd]

Originally posted by Lycan:

Is there a way to prevent animals leaving their pen?

Yes. Make sure they have enough pasture space so they do not need to travel to fill those hungry bellies.

There is a list online that has some info on tiles needed per animal type.
Search for " Dwarf Fortress List of grazing animals pasture space needed "
It will lead you to the Dwarf Fortress Wiki for grazers.

eg:
Animal Horse
Creature Size 500,000
Recommended Pasture Size per individual 7 × 5
Needed Tiles (per rule-of-thumb) 33.44
Sqrt of Needed Tiles 5.8
--------------------------------
Good luck, have fun

edit: I find I can overlap total tiles for multiple animals up to a point, about 5 to 9 ish depending on the animals combined.

[hog_jockey]

Originally posted by Erei:

I know cats like to wander all the time.
Which, to be fair, sound like something totally normal.

Oddly enough, I haven't had any trouble with wandering cats. My dogs, however, think it's a fantastic idea to wander off and pick a fight with a wild rhino for no reason.

[Doctor Zalgo]

Most of my roaming animals are from giants coming through and scaring them all away. These days when I get a bit established I tend to mine out one of the upper layers of the fort and let cavern fungus grow. Then I turn it into a giant internal pasture and its all pretty chill from then on.