Owl pigeons

So if we live up in northern WI and have a couple of owl pigeons, what do we do to keep them hydrated and warm enough over the winter? right now we just have the two in an outdoor cage and we are planning on building something bigger for them.

I do not have owls I have white homers.
I live in Canada on the east coast a small have not province called New Brunswick (doubt if you heard of it).
Warm is not an issue they can stand what ever mother nature can dish out as long as they can avoid a draft and stay dry. Through the winter months I change their water twice daily morning and late afternoon when I feed.

Here is a link to give you a picture of our winters.

https://www.backyardchickens.com/t/738994/chickens-arctic-conditions-prolonged-period

do you know, or can get pics of what kind of owl pigeons you have? as that might help a lot. i keep chinease owl pigeons, and they have extra fluff but upturned underside feathers as that seem to chill them easier on the body, but keep feet warm on up side.. id say build a box with side access panel to work in it, and hole just big enough on bottom of box but with enough room on bottom for inch to foot of insulating wood chips, but a couple feet below top of box.you could use a heating pad on back of box, or roll it lightly around perch, on low or med maybe depending (as know when lived half live up north it got down to 60- but 90- with windchill twice, after second time, i moved down south in spring when roads were clear..). the box could be as small inside available room to a pair only as 24" x 24" x 24" though. for half to dozen birds maybe: 40" x 40" x 40". then just keep any mash, crumble or pelleted feed inside the box or house, along with coffee mug/cup on one of those heated individual warmers. i only had homers up north too, so wouldnt be any help on the fancier breeds as my owls get chilled down here even on cool days. you maybe should get into rollers or homers up there. lol at least add some for heat. haha hope all goes well and your doing good for being responsible and trying to care for your birds good. think i seen a guy on one of these threads from up north WI that has german owls satenttes or similar, maybe he can help.