Saturday, March 5, 2011


This week, WildRescue was called upon to assist with a clutch of barn owl eggs. They were first discovered at a construction site in San Martin on Monday by workers installing a roof on a once-abandoned structure. Roofers saw a large bird fly from an alcove when they arrived in the mornings. On inspection, they found the small white near-round eggs of a barn owl - and dead mice. 

Thankfully, the owner of HTX Builders (San Jose) was concerned for the welfare of the eggs and knew that bird nests were protected by law. Wild birds and their nests are protected under the Migratory Bird Treaty Act and it is federal crime to disturb the nests or destroy the eggs.

Work in the immediate area was halted. We inspected the site, as did an agent from US Fish & Wildlife Service. We concluded the best option was to remove the eggs - something that is usually never done, but in this case, for the un-hatched owlets, it seemed the only option. We were granted permission to do so.

Deanna Barth, one of our newly recruited wildlife rescue technicians, carefully removed the eggs yesterday. She handed them off to Max Salamander who shared the 100 mile journey to deliver the eggs to International Bird Rescue in Fairfield. They were immediately placed into a state-of-the-art incubator that will keep them at just the right temperature and turn them as needed until they hatch - with luck, in 30 days.

As for the adults, it is early enough in the year that the couple should be able to produce at least one, if not two, additional clutches. All they need is a nice safe spot to call their own.

Wednesday we are planning a Barn Owl Box Raising! The owners of the rural property agreed to let us place at least one owl box on site - far from the construction zone. This permanent fixture will no doubt see numerous owls into the world for years to come.

Note: Barn owls are an excellent option for rodent control. Even the young can consume the equivalent of 12 mice each per night. And, owl boxes are not just for countryside homes, they can successfully support barn owls in urban environments. Contact us for information on installing a box on your property! Here is a drawing of our boxes. In cooler areas the extra shelter is not necessary.



  1. my eyes wer almost in tears...
    Great job! well done.

  2. This is all great work, but sets a dangerous precedent. What about the option of leaving the eggs and the nest alone and halting construction until the nestlings fledged? Was the building in question something that could not wait? Hatching eggs in incubators - hooooos going to raise those chicks? People will read these news reports and think this is a solution when a nest inconveniences them. A group I volutneer with has had a similar situation in the past. It involved a tree cutting - a very large, very old oak that was dead inside and in danger of falling on a newly built home at some point in the future. This tree was a long-time barn owl nest site. A biologist hired to give the ok to cut the tree (her judgement was that barn owl nesting had NOT begun) was wrong and after the tree was limbed a nest of eggs were found in the top of the tree trunk. The biologist thought she could just get a permit and send the eggs to Lindsay Wildlife Museum. We argued strongly against that and got the property owners and all involved to agree to leave the limbed tree in place until the owls had left. Without the large limbs, the tree wasn't going to fall on the house. We also had a box placed on the property for future use. I appreciate what you did, and that you use this as a great way to get positive publicity and donations for your wonderful efforts, but I'm not sure publicizing that USFWS allowed eggs to be removed is so great. It's SO HARD to get any enforcement of the MBTA as it is. Thanks.

  3. Thanks for your comment. Many factors went in to the decision. Unfortunately FWS was unable to halt all construction - they could only protect the area immediately around the nest site. This would not have worked - not for this clutch at least. The female would fly off in the mornings - she would have wasted weeks on nonviable eggs. Had there been chicks, we could have placed an owl box nearby and kept the family intact. Hoping to save at least the most recently laid eggs, we asked for permission to remove them and provide the parents a permanent home - one that they probably would not have gotten under other circumstances. As for the owlets, if they hatch they will go to a rehabilitator and from there we to see them wild-fostered. This can't happen until they are older. But, with the many, many opportunities each year - where barn owl nests are destroyed, babies fall, etc. - i am hopeful we'll see them raised wild. However, this will take networking among local rehabilitators and thinking outside of the box! Thanks again for sharing your thoughts! ~ R

  4. I understand with turtle eggs cannot be rotated or the embryo will be scrambled, so when turtle eggs have to be moved they mark the top, carefully move them as best they can without rotating them and take them to their new home. Are owl eggs and birds eggs in general any different? -RHM

  5. Yes - bird eggs need to be turned. Thanks for asking.