Last night I stopped in at a big old gum tree with lots of hollows where I’ve heard owl chicks calling in past years. A bit after dark, there was a mighty screech and an owl flew from a bit away over to a large hole. This was a white Tyto species, which should mean either Masked Owl or Barn Owl down here on the far south coast of NSW. (I don’t believe that Grass Owl occurs this far south and its call sounds very different on the recordings I’ve checked.)
I ended up getting okay but not perfect looks at the bird as it was a completely overcast night. It had a round or oval face with a dark facial disk (of some shade) some spots or streaking on the breast and an overall grayish “cowl” on the head and shoulders. That makes it, without question, a Masked Barn Owl 😉
I’ve been working with Pizzey and the Debus Owls of Australia book on paper and the Morcombe app on an old iPod Touch. While I was in the field, I played myself the calls of all three white Tyto owls (despite messing up my night vision by playing with the screen.) I don’t use playback as I’m not doing anything scientific and I’m already bothering the birds as it is…but it turned out that I *was* using playback. When I played the Masked Owl call to myself, the closest bird (there was a more distant bird in view and third calling not so far off) went completely mental. At that point, I left as I figured I’d bothered them more than enough.
According to Debus, either of these birds, or a Sooty, may respond to the others’ call. So, that the bird responded to the Masked Owl call doesn’t mean that it’s a Masked Owl. (There are, or were, Sooty Owls in this forest – but not right in this spot, so far as I know – plus they’re easier to distinguish from a light-colored Tyto.)
That’s quite a bit of detail about a single sighting but it’s a good example of every white Tyto sighting I’ve had in the past 10 years. I don’t think that I’ve ever felt confident about identifying either of these owls. As far as I know, there’s not much data regarding distribution and abundance of these two species down here so, in that respect, it would be worthwhile to try and identify some birds correctly. We’ve got decent data collection going on this this shire so a correct identification would find a home.
From looking at the field guides, it sounds a lot like the way to identify one of these birds is by knowing the other one really well. The Masked Owl descriptions are “like a Barn Owl but…” and the Barn Owl descriptions are “like a Masked Owl but…” As I don’t know either with certainty, can anyone suggest a good place to start? The calls are quite similar but perhaps that’s the best area to focus on? Getting really good at recognizing the calls of each species? If so, what recordings would any owl experts out there consider authoritative? I’ve got David Stewart’s recordings on the Morcombe app and am happy to hunt for more. I’d like to make sure that I only use recordings that have been reliably identified, given the task at hand.
I’d be keen for some facial feature that’s entirely unambiguous and diagnostic (ha!) I’m not going to count size as a worthwhile field characteristic as my ability to judge size at distance is not better than most people’s and doubtlessly much compromised by the dark.
I noticed that the field guides discuss the feet and legs of the two species quite a bit. Is this really a practical field mark? I seems like a tall order to check out the feet of owls up a tree in the dark! I’ve been spending a lot of time looking at Crakes down here this year and have noticed that some of the field guides emphasize distinguishing characteristics that are hard to see and/or not always visible. (Tip from me: For Spotless Crake in the reeds, try and check the leg color.) Last night was very dark so I’m considering waiting some time and going back again on a brighter night, now that I’ve confirmed a location. With that in mind, I’d also hope to figure out what species these are as the Debus book mentions that Masked Owls breed right around this time and I don’t want to interfere with them.
Thanks in advance for any practical suggestions on distinguishing these birds! I accept that they’re very hard to tell apart and that I’ll generally fail…but I’d like to get it right at least now and then.
If anyone has good advice, please post to the list as I’d guess that many people will be interested in suggestions about these incredible birds. ===============================
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