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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