Homer2101 left a comment on the last post that included this small observation: "Maybe the various things the party might encounter, like monsters, could have stats like weather and season sensitivity stored in a table or database ..."
Aye, there's the rub. No such database exists. Monsters are not listed according to their activity season by season, nor by the temperature at which they are active, nor even by the vegetation in which they inhabit. By and large, biologically, the information on monsters suck. Even where it comes to ordinary biology, what you can find in the books or online isn't that helpful towards determining a mammal's range or commonality ... because biologists don't record stats on the likelihood of creatures occurring randomly.
More's the pity.
Maps like this are helpful, but they're inconsistent, there's no hard data to back up the supposed range, there's little if any information on why the savanna in North Mozambique isn't included in the jackal's range or even if this is a range that's been severely curtailed in the last hundred years. Did Malawi systematically denude the country of this particular species of jackal? What about other species? Or is it possible there's no data for, say, Sudan, because the U.N. agency compiling the numbers did not get permission to camp there and count jackals?
At any rate, I don't have even this much of a map for many real animals, and I still wouldn't have it for owlbears or chimera. One way or another, we just have to make that shit up.