Some pest ate my ninebark in a matter of one week. All leaves eaten.
What can I do. I do not see any bugs and will shrub come back next spring.
It sounds like you had a caterpillar invasion. Something like gypsy moth, sawfly larvae and yellowneck caterpillars are a few possibilities. If the shrub was otherwise healthy and wasn't just planted, it will recover. However, a couple years in a row of defoliation poses a serious threat. Next year, start checking your plant a few weeks before this year's invasion happened. You may need insecticide if the numbers are too large to deal with individually. Post a picture here or at a bug ID website to confirm the pest then get a control agent that is labeled for that caterpillar.