I remember reading this novel in late 80s or early 90s. So, it's gotta be written before this time-frame.
In this novel, humans were travelling in a space cruise liner to visit a unique planet so as to hunt its luminescent creatures with specially designed aircraft. These firefly-like luminescent creatures turn out to be an intelligent species living in another dimension. Based on their intellect, they glowed in different colors in our dimension where for example purple (color of wisdom) is the rarest one to find. A group of space tourist who joined this hunt somehow find themselves in the other dimension with an imminent threat to be getting hunted by their own kind: Humans. They realize then the reckless human hunting come from another dimension which is unknown to these creatures resulted in a significant impact on the population of these creatures, and storing them in our dimension for display purposes was simply killing them due to long imprisonment and dehydration. They try to find a way to return to our dimension and to stop the hunting for good.