Subject: [Tweeters] Great Horned - Barred Owls
Date: Mon Oct 24 15:40:21 PDT 2022
From: Paul Bannick - paul.bannick at gmail.com

Stan,

It would greatly surprise me if a Barred Owl would prey upon a Great Horned
Owl. I suspect the other way around would be more likely.

There are several possible reasons for a decline in Great Horned Owls
besides competition from Barred Owls. First remember that although Great
Horned Owls are very adaptable and can take advantage of most habitats
outside of treeless Arctic and alpine tundra they are most adapted to more
open areas than Barred Owls. Barred Owls are typically found in closed
canopy treed areas that are less ideal to the Great Horned.

All habitats are ephemeral and as they change they often favor one species
over another. The increase in tree cover in many areas would make it
better habitat for Barred Owls and less so for Great Horned Owls.

Secondly, Great Horned Owls tend to avoid people and people areas more than
Great Horned Owls and thus we are more likely to see Barred Owls.
Finally, Great Horned Owls "may be" more likely to consume rats that have
consumed powerful anticollagulate rodenticides that include warfarin and
die from the experience.

Paul

On Mon, Oct 24, 2022 at 2:34 PM Stan Bezimienny <grzebiuszkaziemna at gmail.com>
wrote:


>

> Does anyone have any experience with Great Horned Owls being

> displaced/predated on by Barred Owls? I am trying to interpret my

> observations, the only tidbit of information I found was what Carol Riddell

> posted in "My Edmonds News" in March 2020: " The Great Horned Owl used to

> be seen or heard in the Edmonds area years ago. Birders with many years of

> local experience have mentioned reports of nesting in Southwest County

> Park. Then, whether it was coincidental or causative, Great Horned Owl

> reports declined as Barred Owls moved into the area. ".

>

> Here are the facts:

>

> In Shelton View Forest (Bothell) I easily found (heard, saw) GHO in 2020,

> photographed them on some occasions. GHO were known for a time to nest

> there, locals supposedly see them often, Boy Scouts installed nesting

> platforms etc.

> In 2021 I still saw adults (too early in the day to photograph, low

> light). Interestingly, I also wittnessed a strange event: 2 juveniles

> sitting together in a situation very awkward to photograph, well below the

> grade (I was ona ridge, SVF has steep parts) in rather dense vegetation.

> While I was trying to find a clean angle and setting my big tripod/big lens

> rig, I saw an owl crashing down through the branches towards the juveniles,

> then everybody disappearing below. Shortly after, short distance down the

> trail, I observed/photographed an adult BO feeding, with the bill bloodied

> etc., but I could not see the prey item (high on a tree, view obstructed by

> branches, BO turned back). This was the first time I saw BO in SVF.

> In 2022 on several occasions I photographed BO raising 2 young. Easily

> seen, and heard. No GHO seen/heard.

>

> Caveat: this are only late spring/summer observations, I need to go and

> check in late winter/early spring in 2023.

>

> Are the GHO gone? There is a SVF society of sorts, with a website ect.,

> but I am not sure anyone really looks. And then, the negative is harder to

> report than positive.

>

> I would appreciate yout thoughts,

>

> Stan M

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