Say a moth lays 200 eggs (most lay more). If the population is stable, on average, only 2 will survive to reproduce next year. So the mortality rate among caterpillars is about 99%. But many of those deaths are due to predators of the larvae. By taking it into custody you have a chance of determining the species, not a high chance, but a chance. If you do not take it into custody, you have NO chance. Which is better?