WIth no political merit at stake, it is that time for Democratic presidents to use the Antiquities Act to set aside public lands. Obama is doing this now and I bet he is not finished. There are a number of potential National Monuments that are already somewhere in the political process, which means they would be easy candidates.
I nice list of potentials is here:
Montana's Northern Prairie and New Mexico's Otero Mesa are especially noteworthy because grasslands are the most critically endangered biome in North America. (About 99% destroyed.) For example, when I worked at Tallgrass Prairie National Preserve in Kansas, habitat restoration was nearly impossible because there was no one left alive who could recall what a prairie looked like. And there were no other examples to follow. Imagine the extinction of not just a species, but an entire ecosystem. Shameful.