what is the gestation period of a owl?

Question: what is the gestation period of a owl?
- Keywords:
  bird,
  gestation,
  owl,
  period
Asked by lupopippa to Davie, Gemma, James P, James V, Nuala on 25 Jun 2012.
- James Pope answered on 25 Jun 2012:
  
  Hi lupopippa,
  
  I must admit I don’t know this, so I went and looked it up, it is apparently 30 days. But obviously with all birds, it the period till the young can fly that is really important and this can be depending on species 6-10 weeks.
  
  This article here seems really good:
  
  http://www.owlpages.com/articles.php?section=Owl+Physiology&title=Reproduction
- Gemma Purser answered on 25 Jun 2012:
  
  Like James has found out it depends on which species of owl. In this country we have 5 main species of owl. They are Tawny owl, Little owl, Barn owl, Long eared owl and Short eared owl.

Question: what is the gestation period of a owl?