However, here are some rhyming options, depending on the specific aspect you want to emphasize:
Focusing on size:
* concerns of a large animal, a creature of substantial form
* concerns of a large animal, a behemoth in the storm
Focusing on the animal's nature:
* concerns of a large animal, a creature wild and formal
* concerns of a large animal, a being majestic and regal
Focusing on potential threats:
* concerns of a large animal, its safety in a world so banal
* concerns of a large animal, its existence in a world so feral
More creative options:
* concerns of a large animal, its place in this terrestrial sprawl
* concerns of a large animal, its weight upon this mortal shawl
Ultimately, the best rhyme depends on the context and the specific message you want to convey.