Craft ghillie armor and four dinogates with gates. Find a mine shaped pile of mud in snow area. Kill everything dangerous in the area. Crouch and place dino gates around the mound. The purlovia cant escape the pen now. Ghillie armor very important so you can place gates without it seeing you.
Take Care when searching with flying Mounts for Ovis. They can throw you Off and Paralyse your bird for several seconds. In combination with Packs of wolves this can be your and the birds Ende. I am speaking of experience.
When they are Buried you May See a small mountain.
If your a low level and you know that you will be raided from others in the same position tame one of these dirt kittens to use as a "important item chest" if you are afraid it will be found don't be you are the only one that can see the dirt mound and they use less food while underground