Are animals originally said to be herbivorous (Gen 1:30)?

It seems so. The fact that animals are, of course, carnivorous, you would think it would bear specifically mentioning that the first animals were not so, if that were the point of saying they ate plants. But perhaps saying only that they ate plans was commonly understood, at the time, to mean that animals at only plants (this is a logical fallacy, but it could be an understood implication). Besides, key texts in Rom. 8:18-25 as well as Isaiah 11:6 and 65:25 suggest that on the recreated New Earth, animals will live in peace (as herbivores). So it seems creation at first was absolutely free of death and hence no animals were eaten, and that in the new creation, wiped clean of all sin, there will again be no death, not even of animals. If this were the case, then perhaps the original condition of the creation was equally idyllic. In any case, the difficulty here is that there is there is no scientific evidence that vicious carnivorous predators like lions and eagles ever ate plants; they have sharp teeth (or beaks) and claws (or talons) in order to capture and hold their prey. Why should animals be “punished” by changing their diet in this way as a response by God to man’s sin?