Some people question the meaning of the fall in relation to its introduction of death. They want to limit this to either mankind alone, or restrict it to a 'spiritual' death. This is to avoid the implication of materialist long age of earth and the obvious death of animals this would require prior to the fall. That is, millions of years of animal death recorded in fossils, again, on their terms.
This question, of death before the fall, in reference to animals (the 'living creatures' of Genesis 1:24 excluding plants, bacteria, insects, and the like) seems to want to make God part of the creation, and not separated from it as creator, but separate from it as source of life; despite being so as the creator of all life.
That is, somehow 'life' is external to even God, in some mystical or platonic construction.
Thus some disregard animal death in cavalier fashion. I doubt this can be sustained with a biblical understanding of the relation of Creator and his creation of life; something flowing from his word and the direct action of Christ. The Creator has no 'not-life' in him! Death is the denial of life and the reversion to a not-God state of being; that is, 'not being'. I don't think the hand of God, the Word of God produces death, otherwise, death would not be a cause for grief.
Death in these terms is a direct insult to God and an inversion of his creation (as sin is the inversion of his love).
I write this after recently seeing an aged relative's corpse and learning that our pet dog has multiple malignant tumors and will soon die. At different levels both are death, an assault on the life God created and both confront us with the horror, in different degrees, of the termination of life, of relationship and fellowship (even with an animal).
Our revulsion and grief at death is at its unnaturalness, its reverse of the purpose of the creation, It could not be before the fall, as the direct reading of Genesis 3 and as the ramifications of the fall are described.
Some days later:
We buried our pet dog today. The vet sent her on her way peacefully and without discomfort, or even curiosity at the cannula, she was so sick. The termination of life, even of an animal, was still horrible, it was still the inversion of life, it was still something not of the God of life who made Adam to govern (have care over) the animals that he named (examined, considered, classified, identified). Did Adam expect these animals to then die?
It was not until the fall that decay set in; and death is the result of decay.