Spotted Tussock Moth Caterpillar

I hadn't seen one of these "Yellow Woolly Bear" caterpillars for maybe 20-25 years, so was delighted when I spotted this one. These caterpillars grow to about 4 cm long. The first caterpillars are out by early August and last well into September. This species over-winters as pupae and, in Alberta, the very drab adults are flying in June and July.