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Index of Subjects --0022152d66d5937ac20492e29960 Content-Type: text/plain; charset=ISO-8859-1 Hi James and all, While it's true that I've spent more time with this species during the breeding season than perhaps anyone east of British Columbia, it's still much lower than I would like. The author of the book mentioned is Soren Bondrup-Nielsen, a biology prof at Acadia...I've read both of his books and they're both good reads; he's also a good speaker. On 17 October 2010 22:28, James Hirtle <jrhbirder@hotmail.com> wrote: > ... the male in early March/April does not roost in the same tree from one > night to the next. In fact from one evening to the next the owl could be > one night at one end of the territory and the next night far away at the > other end of the territory. I'm curious to know that in our local studies > for this species if this is what was found. > This has not been investigated here. It does surprise me to read that though, since an unpaired (i.e. courting) male normally calls from the potential nest cavity itself, or very near by. This can start in February, and can continue well into the spring if the male is having trouble attracting a mate. The Boreal Owl is known for not being vocal once paired up...one of the reasons it is a difficult bird to find. > Things are different once a mate is located and enticed to a nest hole. > This occurs I believe during late April into May. > My nest initiation dates have spanned from 20 March to 03 June; earlier is more typical for this owl though. > Now my question is that I was told that if I discovered a Boreal during the > Owl survey that others had to come and confirm the owl. Well I had one a > number of years ago on one route that I ran and there was no doubt in my > mind that it was indeed a boreal owl and it was extremely vocal. Others went > the next night and did not locate the owl. So if the owl was not migrating > and was on territory and if what is said is true in the book about the owl > one night being at one part of the territory and the next night possibly far > away on the other side of its territory, and not roosting in the same tree > every night, then the people who went to check on my owl would not have > found it as was the case. > A few things come to mind. There's a small chance that between your visit and that of the others, the owl was killed, either by a predator or by a car. Not likely, but it could have happened. Something more likely is that given it was the courting season, the male actually got lucky (!) and found his babe-for-the-season. He would then stop calling. However, I would expect that it would still respond to playback (you didn't mention if this was used by the subsequent observers, but I assume so). And by "respond", I don't mean exclusively a vocal response. Owls will sometimes fly in, perch and wait (searching for the invader?). Given their silent flight, you'd have to be looking in the correct direction in order to notice it arriving at all. Or, it may fly in, but not quite come to the edge of the tree line. I have no idea how many times this happens, but I'd suspect most of us who do the owl surveys can think of times when owls have flown in but not vocalized (recorded as "S" on the forms). Can anyone from BSC do a quick data search and find out what percentage of records from owl surveys are sight-based only? Even more likely would be that the bird was off hunting somewhere, perhaps even dealing with the prey and just couldn't be bothered to come into the sound of the invading owl (the playback). A competing male could be dealt with later...losing a mouse might mean going hungry that night. So, confirmation of a calling Boreal Owl can be difficult, and may require repeated visits. I have been asked a few times to confirm others' sightings, but failed each time. Does that mean the birds weren't there? Of course not. James - was your record of the BOOW accepted by the survey coordinators? I'm convinced that BOOWs do exist along the south shore...there is some amazing habitat down there and I've partnered with the Harrison Lewis Centre (http://www.harrisonlewiscentre.org/) to expand my range of study sites for this elusive species. If anyone is nearby some boreal-like forest (high conifer content with some birches and other deciduous trees) and wants to help out as either an individual or group (girl guides, 4H, nature club...) please do get in touch. This request is not restricted to folks on the south shore! Randy _________________________________ RF Lauff Way in the boonies of Antigonish County, NS. --0022152d66d5937ac20492e29960 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hi James and all,<div><br></div><div>While it's true that I've spen= t more time with this species during the breeding season than perhaps anyon= e east of British Columbia, it's still much lower than I would like. Th= e author of the book mentioned is Soren Bondrup-Nielsen, a biology prof at = Acadia...I've read both of his books and they're both good reads; h= e's also a good speaker.</div> <div><br><div class=3D"gmail_quote">On 17 October 2010 22:28, James Hirtle = <span dir=3D"ltr"><<a href=3D"mailto:jrhbirder@hotmail.com">jrhbirder@ho= tmail.com</a>></span> wrote:<br><blockquote class=3D"gmail_quote" style= =3D"margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;"> <div>... the male in early March/April does not roost in the same tree from= one night to the next.=A0 In fact from one evening to the next the owl cou= ld be one night at one=A0end of the territory and the next night far away a= t the other end of the territory.=A0 I'm curious to=A0know that in our = local studies for this species if this is what was found.</div> </blockquote><div><br></div><div>This has not been investigated here. It do= es surprise me to read that though, since an unpaired (i.e. courting) male = normally calls from the potential nest cavity itself, or very near by. This= can start in February, and can continue well into the spring if the male i= s having trouble attracting a mate. The Boreal Owl is known for not being v= ocal once paired up...one of the reasons it is a difficult bird to find.</d= iv> <div>=A0</div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;= border-left:1px #ccc solid;padding-left:1ex;"><div>Things are different onc= e a mate is located and enticed to a nest hole.=A0 This occurs I believe du= ring late April into May.</div> </blockquote><div><br></div><div>My nest initiation dates have spanned from= 20 March to 03 June; earlier is more typical for this owl though.</div><di= v>=A0</div><blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;bor= der-left:1px #ccc solid;padding-left:1ex;"> <div>Now my question is that I was told that=A0if I discovered a Boreal dur= ing the Owl survey that others had to come and confirm the owl.=A0 Well I h= ad one a number of years ago on one route that I ran and there was no doubt= in my mind that it=A0was indeed a boreal owl and it was extremely vocal. O= thers went the next night and did not locate the owl.=A0 So if the owl was = not migrating and was on territory=A0and if what is said is true in the boo= k about the owl one night being at one part of the territory and the next n= ight possibly far away on the other side of its territory, and not roosting= in the same tree every night, then the people who went to check on my owl = would not have found it as was the case.<br> </div> </blockquote></div><br></div><div>A few things come to mind. There's a = small chance that between your visit and that of the others, the owl was ki= lled, either by a predator or by a car. Not likely, but it could have happe= ned.</div> <div><br></div><div>Something more likely is that given it was the courting= season, the male actually got lucky (!) and found his babe-for-the-season.= He would then stop calling. However, I would expect that it would still re= spond to playback (you didn't mention if this was used by the subsequen= t observers, but I assume so). And by "respond", I don't mean= exclusively a vocal response. Owls will sometimes fly in, perch and wait (= searching for the invader?). Given their silent flight, you'd have to b= e looking in the correct direction in order to notice it arriving at all. O= r, it may fly in, but not quite come to the edge of the tree line. I have n= o idea how many times this happens, but I'd suspect most of us who do t= he owl surveys can think of times when owls have flown in but not vocalized= (recorded as "S" on the forms). Can anyone from BSC do a quick d= ata search and find out what percentage of records from owl surveys are sig= ht-based only?</div> <div><br></div><div>Even more likely would be that the bird was off hunting= somewhere, perhaps even dealing with the prey and just couldn't be bot= hered to come into the sound of the invading owl (the playback). A competin= g male could be dealt with later...losing a mouse might mean going hungry t= hat night.</div> <div><br></div><div>So, confirmation of a calling Boreal Owl can be difficu= lt, and may require repeated visits. I have been asked a few times to confi= rm others' sightings, but failed each time. Does that mean the birds we= ren't there? Of course not. James - was your record of the BOOW accepte= d by the survey coordinators?</div> <div><br></div><div>I'm convinced that BOOWs do exist along the south s= hore...there is some amazing habitat down there and I've partnered with= the Harrison Lewis Centre (<a href=3D"http://www.harrisonlewiscentre.org/"= >http://www.harrisonlewiscentre.org/</a>) to expand my range of study sites= for this elusive species. If anyone is nearby some boreal-like forest (hig= h conifer content with some birches and other deciduous trees) and wants to= help out as either an individual or group (girl guides, 4H, nature club...= ) please do get in touch. This request is not restricted to folks on the so= uth shore!</div> <div><br></div><div>Randy<br clear=3D"all">________________________________= _<br>RF Lauff<br>Way in the boonies of<br>Antigonish County, NS.</div> --0022152d66d5937ac20492e29960--
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