Give one reason why caterpillars of the ruby tiger moth have very few predators

They aren't attractive and they have spike-like tufts. I think they are probably nocturnal like their adults too.

Explanation: The early caterpillars are yellowish and gray with sparse tufts of black hair; each abdominal segment with round black dorsolateral spot on each side of midline; later caterpillars are densely hairy black and brown