Shooting nesting owls without disturbing them

Last year I spent many hours shooting nesting great horned owls and burrowing owls, from before hatch until fledging. Today I was shooting a nesting great horned owl, on its eggs during a blustery snow storm that we're enjoying today in Colorado. I was 60-feet away and the owl seemed as if it were not disturbed and casually opened its eyes once or twice and did turn its head as I moved from one side of the nest to the other. I've NEVER even flushed any of these birds over many hours of watching and shooting. This particular GHO has even nested only 20-feet up in a tree that stands out from the tree line and near a road with light travel. The burrowing owls that I shot last spring and summer were only 100-feet from a heavily traveled footpath and would routinely perch on mullein and low bushes near where I had my tripod set up and was sitting on a stool.

I honestly don't think that I've caused any of these owls any real stress. However, today, a photographer approached me and read me the riot act about disturbing the nest of a GHO. He said that was "ruining it" for everybody else and that I was very likely to drive the birds off their nest. He said that even leaving my car would submit the nesting bird to enough stress that it would abandon the eggs. I took this guy's advice as advice. I know that it's illegal to "disturb the nest of a raptor", but I honestly think that means more than merely observing it from 60-feet. I've searched for hours on the internet trying to find discussion of owls being disturbed by prudent photography. I've found thousands of pictures of nesting GHO and burrowing owl families around their burrows. I've spent many hours observing and I've even casually talked about my activities with park rangers and the wildlife management specialist and no one ever seemed disturbed by what I said I was doing.

Do any of the ornithologists here know if GHO and/or burrowing owls are particularly sensitive to human presence while they're nesting? Even if it's not against the law, I don't want to distress the birds and be blamed if eggs are abandoned. This guy that approached me seemed genuinely enraged to the point that he was shaking and gesticulating and threatened to report me to the park manager and other "authorities". Even so, I'm not so certain that he knows what he's talking about. He tends to be a bit full of himself and I'm not confident that he really knows what he's talking about. If there's a period when I shouldn't approach, when does it end for the GHO?

A friend and I planned to sit up out in the prairie dog village at the end of this month to try to catch the burrowing owls' mating dance/flight and mating. Is that a no no?

Thanks in advance.

Hi David. I am not an ornithologist but I don't think you were doing anything unethical or pressuring this owl. I don't think this fellow that confronted you knew beans! If the park rangers tell you to back off, I would but otherwise, I wouldn't worry about it. 60 feet! COME ON! Maybe you should ask the rangers if you are ok with what you are doing and if they are ok, tell this fellow to go pound salt!

Hi David. I have worked with nesting birds for 35 years and can tell you that it is quite unusual for a bird to abandon its nest. The most vulnerable period is very early in incubation, but as incubation and chick rearing (if the chicks aren't precocial and leave the nest soon after hatching) progress, the parents become very attached to their nest and will tolerate quite a lot of disturbance - and will return to the nest as soon as the disturbance ceases. Of course, with all things biological, there is individual variation and some individuals will be less tolerant of disturbance than others - and we shouldn't be disturbing the birds unnecessarily in the first place. Learn to read the bird's body language - if it is disturbed it may leave the nest, call at you, be looking around nervously, etc. Based on your description of the GHO above, I would say the bird wasn't being unduly disturbed by your presence. You can minimize any stress by moving slowly and quietly - give the bird some time to get used to your presence. If the bird's body language and behavior indicate that it is stressed, then back off.

IMO, the person who confronted you was overreacting and ill-informed.

Thank you Dan and Steve. I've read up a little more about owl posturing and I feel even more comfortable with my actions. My owls are usually relaxed and mostly asleep, such that I find myself often waiting 30-minutes for the owl to open its eyes and give me an inscrutable look. I will talk with the park resource manager, just to give him a heads up that he might see me near a nest, since this particular one is not in the woods at all. Unless it snows again, I'll probably wait for the hatch before shooting again.

Hi David- It is clear that you were being careful, watching the bird's reaction, and if there was none as you say, there should be nothing to worry about. Like Steve I've worked with nesting birds for a lot of years and found the ones I worked with (seabirds) extremely tolerant. However, there is quite a bit of variation between species. For example, in Antarctica, almost all species show little reaction to your approach to the recommended 5 metres/15 feet but Giant Petrels are skittish at the nest and we do not approach anywhere near as close. I have not read any reports of owls being skittish at the nest.

Hi,

I have photographed many Barred and a few Gt. Horned Owls as well as Bald Eagles and Red-tails on the nest,from fairly close, without any of them showing any signs of disturbance or concern. A colleague of mine puts up nest boxes for Barred owls and platforms for GH owls, often goes close to check the nests, and often climbs the trees to band the chicks once they are more than a few days old. The adult birds generally fly to a nearby tree, bill clap a few times, then return to the nest a few minutes after he has gone. The only danger is to his head, and he wears a full face helmet. In 30+ years of doing this he has never caused a nest failure. His work and data are well known to, and have been supported by, the local university, and wildlife officials.

Of more concern locally, and perhaps a clue as to what really disturbs raptors at the nest, - a pair of Bald Eagles has nested in a tree adjacent to a local subdivision for the last few years, and successfully raised 2 chicks each year, despite a number of people, and even groups of people, taking photos from the nearby road. This winter all the surrounding trees have been clear cut in order to expand the subdivision, leaving the eagle tree with the large nest as an isolated outpost in the middle of a construction site. So far the birds have failed to appear there this season. Appropriately (or not) the subdivision in named Eagle Landing, and the street names are Tailfeather Court, Aerie Lane, and suchlike.

Richard

Thanks Richard. Such long-term, first hand experience, with positive results gives me more confidence.