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UMichBirders for Saturday, May 3, 2008
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Subject: [birders] RE: Superior Twp. after 6:00 - Bobolinks!
Harrier! Sora! Treefrogs!
From: "Cendra" <cendra(AT)digitalrealm.net>
Date: 3 May 2008 12:58am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Too great!
I saw a lot of them flying over Frog Island last week...
Cendra Lynn, Muggle Birder
OWS, Aw
_____
From: CJ McDonald [mailto:cjmcd77(AT)comcast.net]
Sent: Friday, May 02, 2008 11:34 PM
To: birders(AT)umich.edu
Subject: [birders] Superior Twp. after 6:00 - Bobolinks! Harrier! Sora!
Treefrogs!
Six sharp-looking male Bobolinks in the cornfield at Vreeland and Harris.
Also in this immediate area, many White-crowned Sparrows, as well as Song,
Savannah and Chipping Sparrows. And on Gotfredson, south of Vreeland, I
watched the resident female Northern Harrier that hunts here every evening.
Meadow voles live an exciting life in this field.
In Cherry Hill Preserve, I saw almost no birds. It was a little creepy.
However, at the wetland area north of the entrance, along with the
ubiquitous blackbirds, I heard one Sora (last week I heard two). The
eastern gray treefrogs were at about half-strength; I anticipate deafening
choruses over the next couple of weeks. Interestingly, for the first time
in this area, I also heard some Cope's gray treefrogs mixed in. Cope's has
the harsher, less birdlike call. Have you noticed that Soras, Red-winged
Blackbirds and gray treefrogs sound very similar?
Near Holly years ago, I was standing on a road next to a big pond listening
to the frogs when a car slowed and the elderly driver asked what I was
looking for. I held up my binocs and said birds. She stopped the car and,
hearing the treefrogs, asked, "What kind are those?"
"Those are frogs, ma'am," I said.
"Frogs! They're not frogs. I've been listening to those birds for sixty
years."
I didn't say anything.
"If you don't know what it is," she said with a withering look, "just say
so."
Jim McDonald
Ypsilanti, where frogs sound like birds
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Subject: [birders] Re: OT: Don't Always Root for the Hawk
From: "Russell Emmons" <birdeland(AT)pasty.net>
Date: 3 May 2008 1:01am
Bob, We've had similiar situation here over the years with our ducks, geese,
chickens. Once in awhile hawks but by n' large almost always Great Horned
Owl!
Russ Emmons, Casco Twp. St. Clair county
----- Original Message -----
From: "Bob Tarte" <theduckpen(AT)att.net>
To: <birders(AT)umich.edu>
Sent: Friday, May 02, 2008 5:02 PM
Subject: [birders] OT: Don't Always Root for the Hawk
>I came home from work today and my wife showed me a note from a friend of
>mine who happened to stop by this morning while nobody was home. He heard a
>commotion out in our duck pen and found a hawk had gotten inside.
>
> The top of the pen had been covered with very strong 'poultry netting,' so
> I had assumed that it was raptor proof. And under normal circumstance, it
> would have been. However, an ice fall from our barn roof a couple of
> months ago tore the netting in several places, and the patch-work repairs
> apparently weren't sufficient. When I went out to the pen today, I found
> large rips in two places. I presume the hawk tore the patched-together
> netting while attempting to get out of the pen.
>
> We lost two ducklings, which I hate to see. But it would have been much
> worse if my friend hadn't happened by at just the right time. He caught
> the hawk in a net and released it. He doesn't know what breed it was. I'll
> see if I can find out more when I talk to him this evening.
>
> I love hawks. They are beautiful and deserve a meal as much as any other
> creature. But I don't root for them all of the time!
>
> --
> Bob Tarte
> Author of "Fowl Weather" & "Enslaved by Ducks"
> Algonquin Books of Chapel Hill
> Info and animal photos at: http://www.bobtarte.com
>
> ---
> * birders FAQ - http://www.umich.edu/~bbowman/birds/birders_FAQ.html
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> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
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Subject: [birders] Re: FW: h(air t)earing
From: eba(AT)umich.edu
Date: 3 May 2008 8:07am
Allen & Bruce,
Yes, there is the difference between seeing & observing that you describe;
how subtle it is, perhaps, might depend on how much one can see without
observing. There is an "information overload" with a well-functioning
visual system, and we become selective about what we normally observe out
of the total visual image stream which we receive based on our acquired
interests as well as our instinctive ones, and some of our natural
instinctive observations, such as those of quick motion in our peripheral
vision field, we may have actually suppressed to a certain degree because
we don't need them to survive as crucially as we might have when predators
would make a meal of us if we didn't detect them in time. Now that
response is usually not needed so much for survival except in traffic, and
most of us probably turn up our sensitivity to such motion when we are
pedestrians in traffic or drivers in vehicles. Those who keep their
sensitivity high and the response unchecked when in vehicles but not
driving might become "back-seat drivers" and suffer in their relations with
others because of that, so there might be a natural tendency in our present
environment to turn that response off.
On the other hand, observing can be learned at least to the extent that the
visual system, & the senses in general, provide the information to the
brain that the observation requires. Learning requires doing, and includes
the experience of failure, for the brain to figure out where it went wrong
in processing the information potentially available to it. Part of the
experience at places like Crane Creek (to which I have now been a total of
three times, all within the last two weeks) is that the large bunches of
people gathered at certain places, often all staring off in one direction,
often including some waving their arms in attempts to help others see what
they're looking at. This is disruptive to the person who wants to find a
good spot for observing who simply wants to be there quietly and let the
natural world around him or her resume its natural pace as much as
possible, but it is also a great aid for those whose observational skills
are at the early point in their development and whose eye for picking out
the relevant details on each particular bird does not yet from the
experience of having not only seen a similar one before, but actually
identified it on one's own.
So I am often one of those moving relatively rapidly in the vicinity of
such groups, to get past them and on far enough that it will be some time
before they catch up with me and spoil the tranquility that contributes to
better observation. But other times I find I can learn something from
these crowds because they have found something that I too would like to see
but have previously failed to find on my own. That is something that is
particularly likely to happen with my limited hearing; no amount of
learning to observe will help me get the sounds that are now below my
threshold, but it can help me pick out faint sounds that otherwise I would
not know how to recognize in a more tranquil situation -- that holds true
for all, not just those with hearing loss. But it's harder to learn those
things when the basic sensitivity isn't as good. It helps me to go around
with a few people whose pace fits well with my own when we're not pressured
by crowds, and who have better hearing, and while my eyesight is pretty
good, it helps to have a few more pairs of eyes, too. Also, because I have
developed quite a strong interest in bird photography, I tend to be more
interested in observing closely a bird that I consider "within range" for a
good photograph, and will happily spend much more time observing it than
someone else might who isn't trying to capture more than a mental image of
it.
I have been interested to note, too, how my photographic interests have
contributed to an awareness of some detail which I was not previously
experienced to pick up, and I am learning things which I now recognize
without the assistance of a photographic image that I missed and might
never have picked up without this aid. But while it helps to have photos
showing more subtle differences which I hadn't noticed when observing the
birds singly, I can't expect always to be able to photograph everything I
would like to get to know, so this experience has had the effect of making
me more aware of these subtle differences and helps to guide me in my
attempts to observe birds that are new to me or which I had not observed as
closely before.
Bruce,
Your hearing-assist device is right along lines that I had imagined might
be worth trying, but I wasn't aware that there was actually one available.
I'll try Googling the name you mentioned, but if you have more specific
information on a source for it, I'd appreciate getting that from you, too.
Thanks for mentioning it.
Eric
--On Friday, May 02, 2008 6:23 PM -0400 "Allen T. Chartier"
<amazilia1(AT)comcast.net> wrote:
> Bruce,
>
> I agree with you to a point. But there is a subtle difference between
> seeing and observing. On a job many years ago I was driving a delivery
> van with a younger co-worker, not wearing glasses, in the passenger seat.
> A Red-tailed Hawk flew out and I almost hit it. This guy was looking
> straight ahead and shouldn't have missed it. He probably saw it, but the
> observation didn't register.
>
> And, some money can definitely help with eyesight. Without my glasses or
> contacts on, I cannot focus much beyond the end of my nose. I have
> learned to use the extremely defective equipment I have partly with
> contacts that help me see, but also practicing how to observe.
>
> Allen T. Chartier
> amazilia1(AT)comcast.net
> Inkster, Michigan, USA
> -------------------------------------------------------------------------
> ----
> Website: www.amazilia.net
> HummerNet: www.amazilia.net/MIHummerNet
> Blog: http://mihummingbirdguy.blogspot.com
> -------------------------------------------------------------------------
> ----
> Every day, the hummingbird eats its own weight in food.
> You may wonder how it weighs the food.
> It doesn't. It just eats another hummingbird.
> -- Steven Wright
> =========================================
>
>
> ----- Original Message ----- From: "Bruce M. Bowman"
> <bbowman99(AT)comcast.net>
> To: "Allen T. Chartier" <amazilia1(AT)comcast.net>
> Cc: <birders(AT)umich.edu>
> Sent: Friday, May 02, 2008 6:03 PM
> Subject: Re: [birders] Re: FW: hair tearing
>
>
>> As far as considering eyes and ears as equipment is concerned, and the
>> need to learn how to use "any equipment," yes, you try to make the best
>> use possible of what you've got, whether it's good binocs or bad binocs,
>> good eyesight or bad eyesight, good hearing or bad hearing. The VERY
>> important difference between these types of equipment, though, is that
>> with money you can upgrade your optics (etc.) considerably--i.e., you can
>> match the best that ANYONE ELSE has. The amount that eyeglasses and
>> hearing aids will help you is very limited, though, in this sense
>> (especially, as Eric mentioned, hearing aids). Money will not get you up
>> to where people with good eyesight and hearing are. People with poor
>> eyesight or hearing are at a permanent disadvantage.
>>
>> Bruce
>>
>> From: "Allen T. Chartier" <amazilia1(AT)comcast.net>
>> To: birders(AT)umich.edu
>> Subject: [birders] Re: FW: hair tearing
>> Date sent: Fri, 2 May 2008 17:32:59 -0400
>> Send reply to: "Allen T. Chartier" <amazilia1(AT)comcast.net>
>>
>>> Bruce,
>>>
>>> My reply was mostly tongue in cheek, but it would make sense to consider
>>> eyes and ears equipment. You do have to learn how to use any equipment,
>>> and that takes practice and patience.
>>>
>>> Learning how to move slowly is helpful, but something I see lacking in a
>>> lot of new birders at places like Pelee and Crane Creek is the ability
>>> to simply stay quiet, and to avoid pointing and waving arms around. Get
>>> to your zen birding place and you'll see more...
>>>
>>> Allen T. Chartier
>>> amazilia1(AT)comcast.net
>>> Inkster, Michigan, USA
>>> -----------------------------------------------------------------------
>>> --- --- Website: www.amazilia.net HummerNet:
>>> www.amazilia.net/MIHummerNet Blog: http://mihummingbirdguy.blogspot.com
>>> -----------------------------------------------------------------------
>>> --- --- Every day, the hummingbird eats its own weight in food. You may
>>> wonder
>>> how it weighs the food. It doesn't. It just eats another hummingbird. --
>>> Steven Wright =========================================
>>>
>>>
>>> ----- Original Message -----
>>> From: "Bruce M. Bowman" <bbowman99(AT)comcast.net>
>>> To: "Allen T. Chartier" <amazilia1(AT)comcast.net>
>>> Cc: <birders(AT)umich.edu>
>>> Sent: Thursday, May 01, 2008 10:04 PM
>>> Subject: Re: [birders] Re: FW: hair tearing
>>>
>>>
>>> > Allen-
>>> >
>>> > I can't agree with you there. Birding skills are learned through
>>> > spending a lot of time in the field (etc., etc.). Good eyesight and
>>> > good hearing are things you have or you don't have. Yes :-), I guess
>>> > you could say eyes and ears are equipment, but in that case you'd need
>>> > to up that 10% equipment weight considerably--to 50%? 75%? (And I'd
>>> > cut
>>> > that 50% luck weight down to about 5%. In birding, as in so many
>>> > things, the people who work hard make their own "luck.")
>>> >
>>> > Bruce
>>> >
>>> > From: "Allen T. Chartier" <amazilia1(AT)comcast.net>
>>> > To: birders(AT)umich.edu
>>> > Copies to: <birders(AT)umich.edu>
>>> > Subject: [birders] Re: FW: hair tearing
>>> > Date sent: Thu, 1 May 2008 21:37:54 -0400
>>> > Send reply to: "Allen T. Chartier" <amazilia1(AT)comcast.net>
>>> >
>>> >> Bruce,
>>> >>
>>> >> I think those are subsets of "skill", or perhaps "equipment" :-)
>>> >>
>>> >> Allen T. Chartier
>>> >> amazilia1(AT)comcast.net
>>> >> Inkster, Michigan, USA
>>> >> --------------------------------------------------------------------
>>> >> --- --- --- Website: www.amazilia.net HummerNet:
>>> >> www.amazilia.net/MIHummerNet Blog:
>>> >> http://mihummingbirdguy.blogspot.com
>>> >> --------------------------------------------------------------------
>>> >> --- --- --- Every day, the hummingbird eats its own weight in food.
>>> >> You may
>>> >> wonder how it weighs the food. It doesn't. It just eats another
>>> >> hummingbird. -- Steven Wright
>>> >> =========================================
>>> >>
>>> >>
>>> >> ----- Original Message -----
>>> >> From: "Bruce M. Bowman" <bbowman99(AT)comcast.net>
>>> >> To: "Allen T. Chartier" <amazilia1(AT)comcast.net>
>>> >> Cc: <birders(AT)umich.edu>
>>> >> Sent: Thursday, May 01, 2008 8:49 PM
>>> >> Subject: Re: [birders] Re: FW: hair tearing
>>> >>
>>> >>
>>> >> > Allen-
>>> >> >
>>> >> > You left out keen senses! Good eyesight and good hearing.
>>> >> >
>>> >> > Bruce
>>> >> >
>>> >> >
>>> >> > From: "Allen T. Chartier" <amazilia1(AT)comcast.net>
>>> >> > To: birders(AT)umich.edu
>>> >> > Subject: [birders] Re: FW: hair tearing
>>> >> > Date sent: Thu, 1 May 2008 11:09:50 -0400
>>> >> > Send reply to: "Allen T. Chartier" <amazilia1(AT)comcast.net>
>>> >> >
>>> >> >> Cendra,
>>> >> >>
>>> >> >> As you'll discover as you get more into our shared obsession,
>>> >> >> birding requires luck (50%), patience (25%), skill (15%), and
>>> >> >> equipment (10%).
>>> >> >>
>>> >> >> Allen T. Chartier
>>> >> >> amazilia1(AT)comcast.net
>>> >> >> Inkster, Michigan, USA
>>> >> >> -----------------------------------------------------------------
>>> >> >> --- --- --- --- Website: www.amazilia.net HummerNet:
>>> >> >> www.amazilia.net/MIHummerNet Blog:
>>> >> >> http://mihummingbirdguy.blogspot.com
>>> >> >> -----------------------------------------------------------------
>>> >> >> --- --- --- --- Every day, the hummingbird eats its own weight in
>>> >> >> food. You may wonder how it weighs the food. It doesn't. It just
>>> >> >> eats another hummingbird. -- Steven Wright
>>> >> >> =========================================
>>> >> >>
>>> >> >> ----- Original Message -----
>>> >> >> From: Cendra
>>> >> >> To: birders(AT)umich.edu
>>> >> >> Sent: Thursday, May 01, 2008 12:49 AM
>>> >> >> Subject: [birders] Re: FW: hair tearing
>>> >> >>
>>> >> >>
>>> >> >> Oh, come on! Birds don't hold still long enough to sort all
>>> >> >> that out!! I'm still upset about the sparrows, which I thought
>>> >> >> was one species. I finally saw one that held still long enough
>>> >> >> for me to memorize its patterns, and of course it fits nothing
>>> >> >> in the bird book! Everything else flies into a tree directly
>>> >> >> behind another branch, or lands in a great position for me to
>>> >> >> view it for about one second, or is placed so
>>> >> >> I
>>> >> >> have to look directly into the sun.
>>> >> >>
>>> >> >> Seriously, I think some of you are making this up! And the ones
>>> >> >> of you who get those amazing photographs must have some kind of
>>> >> >> special power that gets the bird to hold still long enough for
>>> >> >> you
>>> >> >> to get it in
>>> >> >> focus.
>>> >> >> That one a few days back that was taken of a wood duck through
>>> >> >> a maze
>>> >> >> of branches just blew me away. Clearly some people on this list
>>> >> >> either have great imaginations or special gifts.
>>> >> >>
>>> >> >> The Muggle Birder,
>>> >> >> Cendra Lynn
>>> >> >> OWS, A2
>>> >> >>
>>> >> >> ----- Original Message -----
>>> >> >> From: Russell Emmons
>>> >> >> To: Sally K Scheer
>>> >> >> Sent: Wednesday, April 30, 2008 6:08 PM
>>> >> >> Subject: Re: [birders] Re: FW: hair tearing
>>> >> >>
>>> >> >>
>>> >> >> And to confuse things even more there is the similiar Brewers
>>> >> >> Blackbird with also differences in male and female and both
>>> >> >> have
>>> >> >> plumage differences in breeding and winter! Rustys'
>>> >> >> differences being the greater of the two! Breeding plumage
>>> >> >> Brewers and Rusty
>>> >> >> males both similiar. Most good field guides give a reliable
>>> >> >> detailed comparison breakdown!! Rustys have yellow eye, Male
>>> >> >> Brewers has whitish eye. Female Brewers always has dark eye.
>>> >> >> More confusing--in migration both species intermingle! Voice
>>> >> >> difference
>>> >> >> between the 2 species also ! Rustys breeding territory way
>>> >> >> north
>>> >> >>
>>> >> >> in
>>> >> >> Canada, Brewers mostly a western bird but breeding occurs in
>>> >> >> Michigan mostly in the northern parts!
>>> >> >>
>>> >> >>
>>> >> >> Russ Emmons, St. Clair county
>>> >> >> ----- Original Message -----
>>> >> >> From: Sally K Scheer
>>> >> >> To: birders(AT)umich.edu
>>> >> >> Sent: Wednesday, April 30, 2008 2:56 PM
>>> >> >> Subject: [birders] Re: FW: hair tearing
>>> >> >>
>>> >> >>
>>> >> >> Maybe you're seeing the male and the female, huh? Try this
>>> >> >> Cornell link for pictures of both. There's the same kind of
>>> >> >> difference between male and female for red-wing blackbirds
>>> >> >> too.
>>> >> >>
>>> >> >>
>>> >> >> http://www.birds.cornell.edu/AllAboutBirds/BirdGuide/Rusty_Blackb
>>> >> >> ird .html
>>> >> >>
>>> >> >>
>>> >> >> Sally Scheer
>>> >> >> Clinton MI
>>> >> >> Bridgewater Township
>>> >> >> SW Washtenaw County
>>> >> >>
>>> >> >> ----- Original Message -----
>>> >> >> From: Cendra
>>> >> >> To: birders(AT)umich.edu
>>> >> >> Sent: Wednesday, April 30, 2008 2:45 PM
>>> >> >> Subject: [birders] FW: hair tearing
>>> >> >>
>>> >> >>
>>> >> >> I really am ready to scream and tear it out because google
>>> >> >> images are showing me two completely different birds when
>>> >> >> I try
>>> >> >> to learn what rusty blackbirds look like. On
>>> >> >>
>>> >> >> http://images.google.com/images?q=rusty%20blackbirds&rls=com.micro
>>> >> >>
>>> >> >> soft:en-us&ie=UTF-8&oe=UTF-8&startIndex=&startPage=1&um=1&sa=N&tab
>>> >> >> =wi there are some that look black and rusty and then
>>> >> >> there are
>>> >> >> some birds I would have said were brown sparrows. They
>>> >> >> look
>>> >> >> NOTHING alike.
>>> >> >>
>>> >> >> Would someone point me to a reliable image of a rusty
>>> >> >> blackbird, please? I think I may have seen some in my
>>> >> >> yard if they are the black-rust ones.
>>> >> >>
>>> >> >> Thanks
>>> >> >>
>>> >> >> Cendra Lynn
>>> >> >> OWS, A2
>>> >> >> ---
>>> >> >> * birders FAQ -
>>> >> >> http://www.umich.edu/~bbowman/birds/birders_FAQ.html *
>>> >> >> photo
>>> >> >> sharing site -
>>> >> >> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
>>> >> >>
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>>> >> >> message
>>> >> >>
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>>> >> >> Your Name.
>>> >> >>
>>> >> >>
>>> >> >>
>>> >> >> -----------------------------------------------------------------
>>> >> >> --- --- -
>>> >> >>
>>> >> >>
>>> >> >> No virus found in this incoming message.
>>> >> >> Checked by AVG.
>>> >> >> Version: 7.5.524 / Virus Database: 269.23.6/1407 - Release
>>> >> >> Date: 4/30/2008 11:35 AM
>>> >> >>
>>> >> >> ---
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>>> >> >> http://www.umich.edu/~bbowman/birds/birders_FAQ.html
>>> >> >> * photo sharing site -
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>>> >> >> Your Name.
>>> >> >>
>>> >> >> ---
>>> >> >> * birders FAQ -
>>> >> >> http://www.umich.edu/~bbowman/birds/birders_FAQ.html * photo
>>> >> >> sharing site -
>>> >> >> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
>>> >> >>
>>> >> >> * To unsubscribe from birders(AT)umich.edu send a blank message to
>>> >> >> lyris(AT)listserver.itd.umich.edu with UNSUBSCRIBE BIRDERS as the
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>>> >> >> --- * birders FAQ -
>>> >> >> http://www.umich.edu/~bbowman/birds/birders_FAQ.html * photo
>>> >> >> sharing site -
>>> >> >> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
>>> >> >>
>>> >> >> * To unsubscribe from birders(AT)umich.edu send a blank message to
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>>> >> >>
>>> >> >>
>>> >> >> ---
>>> >> >> * birders FAQ -
>>> >> >> http://www.umich.edu/~bbowman/birds/birders_FAQ.html
>>> >> >> * photo sharing site -
>>> >> >> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
>>> >> >>
>>> >> >> * To unsubscribe from birders(AT)umich.edu send a blank message to
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>>> >> >>
>>> >> >>
>>> >> >
>>> >> > ------------------------------------
>>> >> > Bruce M. Bowman
>>> >> > Ann Arbor, Michigan USA
>>> >> > Washtenaw Co., southeast Michigan
>>> >> > bbowman99(AT)comcast.net
>>> >> > http://www.umich.edu/~bbowman/birds
>>> >> >
>>> >> >
>>> >> >
>>> >>
>>> >>
>>> >>
>>> >> ---
>>> >> * birders FAQ - http://www.umich.edu/~bbowman/birds/birders_FAQ.html
>>> >> * photo sharing site -
>>> >> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
>>> >>
>>> >> * To unsubscribe from birders(AT)umich.edu send a blank message to
>>> >> lyris(AT)listserver.itd.umich.edu with UNSUBSCRIBE BIRDERS as the
>>> >> Subject line. To resubscribe use SUBSCRIBE BIRDERS Your Name.
>>> >>
>>> >
>>> > ------------------------------------
>>> > Bruce M. Bowman
>>> > Ann Arbor, Michigan USA
>>> > Washtenaw Co., southeast Michigan
>>> > bbowman99(AT)comcast.net
>>> > http://www.umich.edu/~bbowman/birds
>>> >
>>> >
>>> >
>>>
>>>
>>>
>>> ---
>>> * birders FAQ - http://www.umich.edu/~bbowman/birds/birders_FAQ.html
>>> * photo sharing site -
>>> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
>>>
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>>>
>>
>> ------------------------------------
>> Bruce M. Bowman
>> Ann Arbor, Michigan USA
>> Washtenaw Co., southeast Michigan
>> bbowman99(AT)comcast.net
>> http://www.umich.edu/~bbowman/birds
>>
>>
>>
>
>
>
> ---
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Subject: [birders] Re: lights out in Jackson
From: eba(AT)umich.edu
Date: 3 May 2008 8:23am
Interesting.
I had not been aware specifically that birds are drawn to light. Perhaps
it's just my ignorance; I'm certainly familiar with that response in many
insects, and I recall observing many years ago how a large "garden toad"
took advantage of this when I had a plant light near a glass patio door --
the toad would would sit just outside the door at night, and dinner would
come to it. It was really spectacular when the June bugs came out to see
it zap one of them!
So for those of you who know more about this than I do, a question: is it
well established through good studies that this is indeed why there are as
many bird collisions with buildings as there are, or is it conjecture from
other experience? It would certainly help make the argument locally if
there is good research supporting this idea, and if that hasn't been done
yet, then it seems that it would be good to do that.
Eric Arnold
Ann Arbor
--On Friday, May 02, 2008 11:09 PM -0400 Pat Burden <tallerpat(AT)aol.com>
wrote:
> Thought this might be of some interest:
>
> http://tinyurl.com/5x5daf
>
> Pat Burden
> Yale, MI
>
> __________________________________________________
> Plan your next roadtrip with MapQuest.com: America's #1 Mapping Site. ---
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Subject: [birders] White-crowned Sparrows at feeder
From: " Norman" <nvesprini(AT)gmail.com>
Date: 3 May 2008 8:24am
6 White-crowned sparrows at my feeder yesterday and today. Attractive
birds!
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Subject: [birders] Re: lights out in Jackson
From: John Lowry <john(AT)kingbird.org>
Date: 3 May 2008 9:43am
Very well established. Just visit Cornell Lab of Ornithology website
to learn about building collisions.
On May 3, 2008, at 8:23 AM, eba(AT)umich.edu wrote:
> Interesting.
>
> I had not been aware specifically that birds are drawn to light.
> Perhaps it's just my ignorance; I'm certainly familiar with that
> response in many insects, and I recall observing many years ago how
> a large "garden toad" took advantage of this when I had a plant
> light near a glass patio door -- the toad would would sit just
> outside the door at night, and dinner would come to it. It was
> really spectacular when the June bugs came out to see it zap one of
> them!
>
> So for those of you who know more about this than I do, a question:
> is it well established through good studies that this is indeed why
> there are as many bird collisions with buildings as there are, or is
> it conjecture from other experience? It would certainly help make
> the argument locally if there is good research supporting this idea,
> and if that hasn't been done yet, then it seems that it would be
> good to do that.
>
> Eric Arnold
> Ann Arbor
>
> --On Friday, May 02, 2008 11:09 PM -0400 Pat Burden
> <tallerpat(AT)aol.com> wrote:
>
>> Thought this might be of some interest:
>>
>> http://tinyurl.com/5x5daf
>>
>> Pat Burden
>> Yale, MI
>>
>> __________________________________________________
>> Plan your next roadtrip with MapQuest.com: America's #1 Mapping
>> Site. ---
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>> birders_FAQ.html *
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>> unsubscribe
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>
>
>
>
>
> ---
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Subject: [birders] Do birds sleep? - pics
From: "Jerry Jourdan" <jourdaj(AT)gmail.com>
Date: 3 May 2008 9:48am
----INCLUDING text/plain MIME SECTION----
I've finally answered the age-old question. Yes! But very
uncomfortably....
http://www.pbase.com/jourdaj/image/96498130
http://www.pbase.com/jourdaj/image/96498129
UM-Dearborn was slightly active this morning between 7 - 8 am:
Yellow Warbler - 2
Yellow-rumped Warblers - 4
Chestnut-sided Warbler - 2
Blue-gray Gnatcatcher - 1
Baltimore Oriole - 1
Palm Warblers - 6
Black-throated Green - 1 possibly 2
Black-and-White Warbler - 1
Wood Thrush - 1
Ovenbird - 1
White-throats and -crowned - lots
House Wrens - 6
Carolina Wren - 1
Field Sparrow - 1
Jerry
http://jerryjourdan.blogspot.com
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Subject: [birders] birds and light
From: "Bruce Robertson" <roberba1(AT)msu.edu>
Date: 3 May 2008 10:47am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Guys,
Bird collisions with tall towers are very common. There is a website called
Towerkill that attempts to bring together a lot of the literature on this
subject. The most collisions occur at the tallest towers that are more
likely to intersect the paths of migrating birds. Collisions are most common
when towers are brightly lit, especially when clouds or fog are dense. This
has the effect of creating a bright and more detectable source of lighting.
Why are birds attracted to light? It seems to be related to birds' use of
celestial cues during migration, the moon in particular.
Here's where we get into more speculation, but I am writing a manuscript on
a closely related subject so I've done quite a bit of thinking on this. I
think what is going on here is that, as migrating birds approach a lit tower
the position of the tower begins to change relative to the bird. This
doesn't happen when the birds are orienting to the moon because the
moonlight is always at infinity. Because the tower light isn't, birds change
their course as they pass the tower, keeping the artificial moon in the
correct position for their time-corrected navigational course. The overall
effect is that birds slowly spiral around the tower, getting closer and
closer until they finally collide.
This is likely a manifestation of what is termed an 'evolutionary trap',
cases in which, due to rapid environmental change, the cues that organisms
animals have evolved to correctly guide their behavior are no longer
reliable. In this case, reliance upon the moon as a primary navigational cue
is now a maladaptive behavior if you happen to be an individual migrating
through a maze of brightly lit towers that have never existed before in
evolutionary history.
I am writing manuscript with the title, "Polarized light pollution". It
turns out that many organisms are capable of seeing polarized light, light
whose wavelengths are vibrating in the same plane. For example, when
sunlight bounces of the smooth surface of water bodies, it becomes
horizontally polarized. The atmosphere also polarizes the light that passes
through it, leaving polarization patterns in the sky that we can't see, but
that give you a reliable idea of the location of the sun, or moon, even when
they are completely covered with clouds. Migratory birds appear to use this
as a redundant migratory cue, in addition to the sun/moon and the
geomagnetic field of the earth. What is polarized light pollution? It turns
out that all sorts of man-made objects polarize light: dark-colored cars,
windows, solar cells, asphalt, gravestones, oil-spills, tar-pits. These tend
to polarize light even more strongly than the water or atmosphere, providing
a supernormal cue for waterbirds, aquatic insect and potentially even
migratory birds, that can mislead them. For example, it could be that one
reason that bird collisions with buildings are so common is not that they
reflect light and make them relatively invisible to the bird, but rather
that they polarize light, attracting the bird.
Bruce Robertson
Postdoctoral Fellow
W.K. Kellogg Biological Station
Michigan State University
3700 East Gull Lake Drive
Hickory Corners, MI 49060
<mailto:roberba1(AT)msu.edu> roberba1(AT)msu.edu
<mailto:brucerobertson(AT)hotmail.com> brucerobertson(AT)hotmail.com
269-671-2536 (office)
206-718-9172 (cell)
269-671-4485 (FAX)
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Subject: [birders] White-crowned sparrow, chipping sparrows at feeder
From: <chases(AT)peoplepc.com>
Date: 3 May 2008 10:54am
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
. Saturday, 3 May 2008
After suffering diminished numbers of birds at our feeder over the years =
as development in southeast Ann Arbor removed nearby natural areas, I =
was pleased to see a pair of chipping sparrows and a white-crowned =
sparrow foraging beneath the feeders this morning. A blue jay also =
appeared. At the same time, a house wren was checking out the bird =
boxes hanging from the eaves. Over the last week, white-throated =
sparrows also came by to feed.
Dick Chase
Ann Arbor
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Subject: [birders] Re: birds and light
From: "Sally K Scheer" <winerat(AT)villagecorner.com>
Date: 3 May 2008 12:00pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
How is this polarized light detected. ie How do we know it's there? My =
only acquaintance with polarized light is polarized sunglasses!=20
And how does this polarization vs invisibility thru reflection affect =
efforts to avoid bird collisions in our home settings?=20
And further, if dark cars and tar pits and some of the other things you =
mention also polarize light, this bird confusion via polarization must =
have been going on for a long long time. So many natural objects would =
be causing problems that the poor birds would have very little chance of =
making it thru any migration.
Interesting thoughts and ideas here.
Sally Scheer
Clinton MI
Bridgewater Township
SW Washtenaw County=20
----- Original Message -----=20
From: Bruce Robertson=20
To: birders(AT)umich.edu=20
Sent: Saturday, May 03, 2008 10:47 AM
Subject: [birders] birds and light
Guys,=20
=20
Bird collisions with tall towers are very common. There is a website =
called Towerkill that attempts to bring together a lot of the literature =
on this subject. The most collisions occur at the tallest towers that =
are more likely to intersect the paths of migrating birds. Collisions =
are most common when towers are brightly lit, especially when clouds or =
fog are dense. This has the effect of creating a bright and more =
detectable source of lighting. Why are birds attracted to light? It =
seems to be related to birds' use of celestial cues during migration, =
the moon in particular.=20
=20
Here's where we get into more speculation, but I am writing a =
manuscript on a closely related subject so I've done quite a bit of =
thinking on this. I think what is going on here is that, as migrating =
birds approach a lit tower the position of the tower begins to change =
relative to the bird. This doesn't happen when the birds are orienting =
to the moon because the moonlight is always at infinity. Because the =
tower light isn't, birds change their course as they pass the tower, =
keeping the artificial moon in the correct position for their =
time-corrected navigational course. The overall effect is that birds =
slowly spiral around the tower, getting closer and closer until they =
finally collide.=20
=20
This is likely a manifestation of what is termed an 'evolutionary =
trap', cases in which, due to rapid environmental change, the cues that =
organisms animals have evolved to correctly guide their behavior are no =
longer reliable. In this case, reliance upon the moon as a primary =
navigational cue is now a maladaptive behavior if you happen to be an =
individual migrating through a maze of brightly lit towers that have =
never existed before in evolutionary history.=20
=20
I am writing manuscript with the title, "Polarized light pollution". =
It turns out that many organisms are capable of seeing polarized light, =
light whose wavelengths are vibrating in the same plane. For example, =
when sunlight bounces of the smooth surface of water bodies, it becomes =
horizontally polarized. The atmosphere also polarizes the light that =
passes through it, leaving polarization patterns in the sky that we =
can't see, but that give you a reliable idea of the location of the sun, =
or moon, even when they are completely covered with clouds. Migratory =
birds appear to use this as a redundant migratory cue, in addition to =
the sun/moon and the geomagnetic field of the earth. What is polarized =
light pollution? It turns out that all sorts of man-made objects =
polarize light: dark-colored cars, windows, solar cells, asphalt, =
gravestones, oil-spills, tar-pits. These tend to polarize light even =
more strongly than the water or atmosphere, providing a supernormal cue =
for waterbirds, aquatic insect and potentially even migratory birds, =
that can mislead them. For example, it could be that one reason that =
bird collisions with buildings are so common is not that they reflect =
light and make them relatively invisible to the bird, but rather that =
they polarize light, attracting the bird.=20
=20
=20
=20
Bruce Robertson=20
Postdoctoral Fellow
W.K. Kellogg Biological Station
Michigan State University
3700 East Gull Lake Drive
Hickory Corners, MI 49060
=20
roberba1(AT)msu.edu
brucerobertson(AT)hotmail.com
269-671-2536 (office)
206-718-9172 (cell)
269-671-4485 (FAX)
=20
=20
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http://www.umich.edu/~bbowman/birds/se_mich/photos.html=20
* To unsubscribe from birders(AT)umich.edu send a blank message to
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line. To
resubscribe use SUBSCRIBE BIRDERS Your Name.=20
-------------------------------------------------------------------------=
-----
No virus found in this incoming message.
Checked by AVG.=20
Version: 8.0.100 / Virus Database: 269.23.8/1413 - Release Date: =
5/3/2008 11:22 AM
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Subject: [birders] Polarized Light
From: Fred Kaluza <fkaluza(AT)yahoo.com>
Date: 3 May 2008 9:21am
Bruce, I thought polarized light is any light that is
reflected. Therefore, sunlight (before it hits our
atmosphere) would be direct and moonlight must
therefore be polarized. Your navigational references
to distant light sources are confirmed and birds
suffer the same fate as insects like moths who
hopelessly spiral around a candle flame while trying
to fly in a straight line and eventually meet their
fate in a flaming end..
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Subject: [birders] White-eyed Vireo, Whip-poor-will, Ford House,
Grosse Pointe Shores
From: BRapai(AT)aol.com
Date: 3 May 2008 12:33pm
----INCLUDING text/plain MIME SECTION----
Birders:
Gotta run to a soccer game, but I had to take time to mention that the Ford
House in Grosse Pointe Shores was very birdy this morning. Among the best of
the best were a White-eyed Vireo in the far north-east corner of the property,
and a Whip-poor-will along the trail to Bird Island.
The Ford House is on Lake Shore Drive in Grosse Pointe Shores, right at the
border with St. Clair Shores, between Vernier and Nine Mile Road.
Good birding!
Bill Rapai
Grosse Pointe
**************
Wondering what's for Dinner Tonight? Get new twists on family
favorites at AOL Food.
(http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001)
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Subject: [birders] Warblers on one page
From: "Wild Birds Unlimited" <RosannKovalcik(AT)comcast.net>
Date: 3 May 2008 12:38pm
Does anyone know how to reach Barbara Winter Gommi who created the "Warblers
on One Page" folded I.D. pamphlet? Thanks in advance,
Rosann Kovalcik
Wild Birds Unlimited
20485 Mack Avenue
Grosse Pointe Woods, MI 48236
313-881-1410
www.wbu.com/grossepointewoods
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Subject: [birders] Windsor Hooded Warblers, etc. -May 1-3
From: fred john urie <fred_urie(AT)hotmail.com>
Date: 3 May 2008 4:43pm
A Hooded Warbler has been behind the Ojibway Nature Centre for
6 days. Today I found a second male just off of Huron Line on the
bike trail.
Other sightings for Ojibway Complex:
May 1
Tennessee 1
Black-thr. Green 8
Palm Warbler 5
May 2
Blackburnian 1
Blue-winged Warbler 1
Indigo Bunting 1
Least Flycatcher 1
May 3
Nashville 11
Am. Redstart 2
C.Yellowthroat 9
Cerulean - (tallgrass area)
Ovenbird 4
Indigo Bunting 2
Orchard Oriole 5
Good birding
Fred Urie
Windsor
fred_urie(AT)yahoo.com
_________________________________________________________________
Turn every day into $1000. Learn more at SignInAndWIN.ca
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Subject: [birders] light and birds
From: "Bruce Robertson" <roberba1(AT)msu.edu>
Date: 3 May 2008 12:48pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Hey,
Just thought I'd attempt to answer a few questions:
I thought polarized light is any light that is reflected.
* Light reflects off particles and molecules in the air, buildings,
trees, everything, but it is only polarized if it reflects off very smooth
objects. The main naturally occurring polarizer is water. Vegetation, rocks
and other smooth objects might do this to a lesser degree. The atmosphere
polarizes light via scattering, which is sort of different.
How is this polarized light detected. ie How do we know it's there? My only
acquaintance with polarized light is polarized sunglasses!
* Exactly right. Polarizing sunglasses let through light that is
vertically polarized (up and down), but not that which is horizontally (left
and right) polarized by the surface of the water. Some of the light at
different diagonals might make it though, too. Polarizing filters used for
scientific purposes may be more complicated, but use this same method.
And how does this polarization vs invisibility thru reflection affect
efforts to avoid bird collisions in our home settings?
* I'm not sure! I don't think there is a whole lot of information.yet.
Bruce Robertson
Postdoctoral Fellow
W.K. Kellogg Biological Station
Michigan State University
3700 East Gull Lake Drive
Hickory Corners, MI 49060
<mailto:roberba1(AT)msu.edu> roberba1(AT)msu.edu
<mailto:brucerobertson(AT)hotmail.com> brucerobertson(AT)hotmail.com
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Subject: [birders] Worm-eating Warbler at Dolph Nature Area Ann Arbor
From: Roger Kuhlman <rkuhlman(AT)hotmail.com>
Date: 3 May 2008 12:50pm
----INCLUDING text/plain MIME SECTION----
Around 8am Saturday morning I found a Worm-eating Warbler at Dolph Nature A=
rea in western Ann Arbor. The bird was in the northwest section of preserve=
across the 'Boy scout?' bridge and was feeding in several areas of the for=
est understudy on the ground. At no time when I was present did it sing but=
a couple of times it popped a few feet up in the shrubby undergrowth where=
it gave excellent views--a kind of plumpish brown bird with distinctive he=
ad striping.
=20
Other interesting birds at Dolph included two Northern Parulas, two Norther=
n Waterthrushes, and several singing Least Flycatchers.
=20
Roger Kuhlman
Ann Arbor, Michigan
5/3/2008=
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Subject: [birders] Wood Ducks?
From: Fred Kaluza <fkaluza(AT)yahoo.com>
Date: 3 May 2008 10:34am
Where should Wood Ducks be in terms of nesting, eggs
laid, hatching and fledging by this date? Also, I saw
a female RBN today for the first time in like6 weeks!
Nice to know she's still around. Despite RWBB and
Grackles around, she took a peanut and flew off.
Feeding young perhaps?
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Subject: [birders] Hummingbird Problem
From: "bflylady27(AT)netzero.net" <bflylady27@netzero.net>
Date: 3 May 2008 5:55pm
----INCLUDING text/plain MIME SECTION----
=
After visiting several greenhouses, there seems to be a huge problem wi=
th hummers getting in and not getting out so they die. Any ideas. My nei=
ghbor has one right now. Connie
_____________________________________________________________
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Subject: [birders] Polarized light and basic physics
From: eba(AT)umich.edu
Date: 3 May 2008 2:10pm
Light doesn't reflect off of molecules, it scatters. Scattering is the
word physicists use to describe the interaction of light or other physical
waves from objects which are generally smaller than a wavelength, and the
resulting scattered waves tend to go in all directions, although not
necessarily with equal amplitudes or other physical properties, of which
polarization is one.
When a surface is smooth, and by smooth we mean that it is pretty uniform
without bumps or wrinkles or other departures from a plane or smoothly
curved surface that are comparable in size to a wavelength, then we can get
secular, or mirror-like, reflection from these surfaces. If the smooth
area is large enough, we can get a visually-detectable reflection which
looks like an independent light source.
If the material has the property of being dielectric at the frequency of
the wave motion, then the reflected wave can also be polarized. However,
the degree of polarization depends crucially on the angle at which the wave
strikes and leaves the surface, and for the principal reflection, i.e. the
brightest one, the angle of incidence equals the angle of reflection, just
like in a mirror. At a certain angle of incidence & reflection the
polarization is greatest, and can be a high fraction of the total
reflection, depending on the exact nature of the reflecting body. At other
angles, the polarization is less complete; as bird's view of an object
giving polarized light by reflection changes, the degree of polarization it
would be able to see would change very much, so it would be hard to explain
a spiraling phenomenon on the basis of polarization because it wouldn't
stay in the polarized beam unless it were heading straight for it in the
first place, and the use of light sources as navigational aids doesn't
generally involve heading for them so much as keeping it at a relatively
constant angle, at least for a fraction of the day or night. But even if a
bird tries to keep a reflected polarized source at a fixed angle, it would
see changing polarization as its position relative to the reflecting object
changed. It's hard to imagine that reflections from relatively small
objects would be more than noise sources in overall patterns of
polarization that a bird might detect. They would simply mingle in with
lots of other noise sources, I suspect, coming from lots of other objects
whose light is polarized to varying degrees, and that includes leaves --
ask a photographer who uses a polarizing filter if it's just water, sky,
and shiny non-metallic (i.e. dielectric) objects that are affected, and
you'll find out that there are lots of other things that are affected to a
degree, too, although the details of the effect are much less easily
predicted than with the sky and the discrete reflections from large smooth
objects.
Moonlight isn't polarized to any significant degree because its surface
isn't smooth enough, and that is true for many other more-or-less amorphous
substances like rocks which haven't been worn smooth. Reflections from
metallic objects don't generally result in polarized reflections from
non-polarized light sources, but they can pass on the polarization of
incident light which was already polarized, whereas reflected light from
rough surfaces looses its polarization even when the illuminating light is
strongly polarized.
Eric Arnold
--On Saturday, May 03, 2008 12:48 PM -0400 Bruce Robertson
<roberba1(AT)msu.edu> wrote:
>
>
> Hey,
>
>
>
> Just thought I'd attempt to answer a few questions:
>
>
>
> I thought polarized light is any light that is reflected.
> * Light reflects off particles and molecules in the air, buildings,
> trees, everything, but it is only polarized if it reflects off very
> smooth objects. The main naturally occurring polarizer is water.
> Vegetation, rocks and other smooth objects might do this to a lesser
> degree. The atmosphere polarizes light via scattering, which is sort of
> different.
>
>
>
> How is this polarized light detected. ie How do we know it's there? My
> only acquaintance with polarized light is polarized sunglasses!
> * Exactly right. Polarizing sunglasses let through light that is
> vertically polarized (up and down), but not that which is horizontally
> (left and right) polarized by the surface of the water. Some of the light
> at different diagonals might make it though, too. Polarizing filters used
> for scientific purposes may be more complicated, but use this same
> method.
>
>
>
> And how does this polarization vs invisibility thru reflection affect
> efforts to avoid bird collisions in our home settings?
> * I'm not sure! I don't think there is a whole lot of
> information...yet.
>
>
>
>
>
> Bruce Robertson
> Postdoctoral Fellow
>
> W.K. Kellogg Biological Station
>
> Michigan State University
>
> 3700 East Gull Lake Drive
>
> Hickory Corners, MI 49060
>
>
>
> roberba1(AT)msu.edu
>
> brucerobertson(AT)hotmail.com
>
> 269-671-2536 (office)
>
> 206-718-9172 (cell)
> 269-671-4485 (FAX)
>
>
>
> ---
> * birders FAQ - http://www.umich.edu/~bbowman/birds/birders_FAQ.html
> * photo sharing site -
> http://www.umich.edu/~bbowman/birds/se_mich/photos.html
>
> * To unsubscribe from birders(AT)umich.edu send a blank message to
> lyris(AT)listserver.itd.umich.edu with UNSUBSCRIBE BIRDERS as the Subject
> line. To
> resubscribe use SUBSCRIBE BIRDERS Your Name.
---
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[ << | >> | ^^ ]
Subject: [birders] Safe Passage Great Lakes-Let's Do It
From: "bflylady27(AT)netzero.net" <bflylady27@netzero.net>
Date: 3 May 2008 6:25pm
----INCLUDING text/plain MIME SECTION----
=
This is a project that can make a difference. All thirteen buildings =
in Jackson have committed to turning off their lights from the sixth flo=
or up from 11:00PM to Daylight during migration. (March 15 through May 3=
1 and August 15 through October 31). Three of the apartment buildings ha=
ve notified their tenants about the project so they may be pulling their=
blinds. Consumers is on a timer that goes out at 10:30. And by law, som=
e lights must be on in the stairwell of some buildings. Also, the airpor=
t was contacted to make sure there was not a problem with lights being o=
ut on top of the buildings.
Getting started:
1. Take a night drive around your city and make notes as to who has t=
heir lights on after 11.
2. Personally visit each building and give them a hand-out with proj=
ect information.
3. Get a write up in your local newspaper
4. Take another 11 PM drive and note who still has their lights on. =
Contact those buildings .
5. Give names of buildings to MAS for the honor roll
6. Give them credit in the paper
Jackson Audubon as a bonus found out we have a pair of peregrine falcons=
on the county building. We challenge you to help save the migrating bi=
rds. =
_____________________________________________________________
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$33 a month for 12 months when you purchase cable, internet and phone!
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---
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[ << | >> | ^^ ]
Subject: [birders] Crosswinds American Bitterns Wilson's Warbler
From: "Daryl & Gail Aspery" <gr8gray(AT)wowway.com>
Date: 3 May 2008 2:28pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
I made a early visit to Crosswinds today. American Bitterns can be heard =
calling in the usual locations, in Phase 1 in the SW corner, in Phase 2 =
off Arkrona and Clark. I also had an early Wilson's Warbler.
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Subject: [birders] Re: Do birds sleep? - pics
From: "Allen T. Chartier" <amazilia1(AT)comcast.net>
Date: 3 May 2008 2:59pm
This is a multi-part message in MIME format.
----INCLUDING text/plain MIME SECTION----
Jerry,
I highly recommend "Birds Asleep" by Alexander Skutch.
Allen T. Chartier
amazilia1(AT)comcast.net
Inkster, Michigan, USA
-------------------------------------------------------------------------=
----
Website: www.amazilia.net
HummerNet: www.amazilia.net/MIHummerNet
Blog: http://mihummingbirdguy.blogspot.com
-------------------------------------------------------------------------=
----
Every day, the hummingbird eats its own weight in food.
You may wonder how it weighs the food.=20
It doesn't. It just eats another hummingbird.=20
-- Steven Wright
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
----- Original Message -----=20
From: Jerry Jourdan=20
To: birders(AT)umich.edu=20
Sent: Saturday, May 03, 2008 9:48 AM
Subject: [birders] Do birds sleep? - pics
I've finally answered the age-old question. Yes! But very =
uncomfortably....
http://www.pbase.com/jourdaj/image/96498130
http://www.pbase.com/jourdaj/image/96498129
UM-Dearborn was slightly active this morning between 7 - 8 am:
Yellow Warbler - 2
Yellow-rumped Warblers - 4
Chestnut-sided Warbler - 2
Blue-gray Gnatcatcher - 1
Baltimore Oriole - 1
Palm Warblers - 6
Black-throated Green - 1 possibly 2
Black-and-White Warbler - 1
Wood Thrush - 1
Ovenbird - 1
White-throats and -crowned - lots
House Wrens - 6
Carolina Wren - 1
Field Sparrow - 1
Jerry=20
http://jerryjourdan.blogspot.com
--- * birders FAQ - =
http://www.umich.edu/~bbowman/birds/birders_FAQ.html * photo sharing =
site - http://www.umich.edu/~bbowman/birds/se_mich/photos.html * To =
unsubscribe from birders(AT)umich.edu send a blank message to =
lyris(AT)listserver.itd.umich.edu with UNSUBSCRIBE BIRDERS as the Subject =
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Subject: [birders] Blue Jay gang
From: "Cendra" <cendra(AT)digitalrealm.net>
Date: 3 May 2008 3:00pm
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----INCLUDING text/plain MIME SECTION----
Sitting at the edge of Slauson field yesterday evening about 6 pm, I watched
a Blue Jay gang come and go and come back and go numerous times. There were
at least a dozen of them, and they were announcing themselves loudly, waving
bicycle chains and tire irons, threatening anyone who could hear. They
would fly out to the northwest, then roar back and land in the tops of trees
at the southern and western edges of the park. Then they would head back to
the northwest, sounding as though they had another site of intimidation to
go to.
Cendra Lynn, Muggle Birder
OWS, A2
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Subject: [birders] Safe Passage in Washtenaw County
From: "Ray Stocking" <rstocking(AT)gmail.com>
Date: 3 May 2008 3:36pm
All,
As a follow up to the good things mentioned here about the Safe
Passage program in Jackson County, I would like to let you know what
has been taking place in Washtenaw County. The Washtenaw Audubon
Society has been actively pursuing a Safe Passage program since
December 2007, however we have not been as fortunate as Jackson
Audubon in that we have not rounded up volunteers committed to
surveying buildings after 11pm and/or walking door-to-door asking
building owners to comply with this program. The report of a dead
Common Moorhen found last week at the University of Michigan Hospital
speaks volumes for what this program means. Time is wasting and we
need to act quickly.
I wrote an article that appeared in our newsletter last March. It was
also printed in two other publications informing concerned birders
about this program. For your convenience, I have posted it below.
Please read the entire article and contact me directly if you would
like to support this program in Washtenaw County. Together, we can
make a difference for our migratory friends as they pass through this
wonderful community we call home.
Thank you for your support,
Ray
Ray Stocking
President, Washtenaw Audubon Society
Ann Arbor, MI
(734) 645-8110
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Originally published in March 2008
Research indicates that millions, if not billions of birds are dying
each year in North America from collisions with tall buildings. The
lights of the buildings interfere with the birds' navigation system.
The birds either fly in circles around the building and die of
exhaustion or they fly into the windows.
Today's technology allows radar to show us how birds migrate at night
in a broad front across the Great Lakes, and millions of birds use the
skies over Michigan during their spring and fall migrations. Over 250
species, including warblers, thrushes, and tanagers, some declining
steeply in numbers, fly over Michigan during their migration. The
lights of tall buildings such as those in Ann Arbor and surrounding
communities often confuse the navigation systems of birds flying
nearby. To date, nothing has been done within Washtenaw County to
address this problem.
For those of you who are not aware of the problem, here are a few key points:
• Migratory birds are drawn to the lights of buildings and can crash
into the windows.
• Migratory birds circle the lighted buildings and eventually become
exhausted and fall to the ground.
• In one study, researchers collected 30,000 dead birds outside a
Chicago building over 3 years.
• Results from turning out the lights decreased the number of dead
birds found by 80%.
In March 2007 Michigan Governor Jennifer Granholm signed a
proclamation designating dates in the spring and fall as "Safe Passage
Great Lakes Days." The proclamation called attention to the threat to
migratory birds posed by the lights of tall buildings. The designated
"Safe Passage Great Lakes" dates in Michigan are March 15 through May
31 and August 15 through October 31. The Detroit Audubon Society and
Michigan Audubon Society are partners in leading the "Safe Passage"
effort in Michigan, which is patterned after Chicago Audubon's "Lights
Out" campaign. Project Safe Passage Great Lakes aims to help birds by
asking owners and managers of buildings that are five stories or
higher to turn their lights off (or draw curtains and blinds) above
the fifth floor between 11 p.m. and 5 a.m. every night.
At the Michigan Audubon Society's Central Regional Meeting this past
December, the Safe Passage campaign was brought to the forefront. The
featured speaker at this event was Rochelle Breitenbach, past
president of Detroit Audubon, who has been working on this project in
Southeast Michigan, primarily in Detroit. Ms. Breitenbach explained
how businesses, government agencies, and property owners are being
encouraged to turn off their lights (or draw blinds and curtains)
above the fifth floor during the designated hours.
We heard about existing projects in Chicago, Minneapolis and Toronto.
Chicago has been the most successful city in the United States for
taking action and protecting birds. Their program, Lights Out, which
has the support of the mayor, has saved the lives of more than 10,000
birds each year. We discussed further how the Washtenaw Audubon
Society can help with this cause
You might say to yourself, Washtenaw County doesn't have skyscrapers.
While it is true that skyscrapers are a leading cause of these
migratory deaths, many buildings in Ann Arbor, Ypsilanti and other
surrounding communities do have buildings over five stories tall. A
five-story building with its lights on at night is just as likely as a
50-story building to distract a bird (or a flock of birds).
Washtenaw Audubon Society is proud to be joining the ranks of The
Detroit Audubon and Michigan Audubon Society in supporting this cause.
Turning off lights is a win-win situation. Birds' lives will be
spared, money and electricity will be saved, and pollution will be
reduced. The data provided from the Detroit, Chicago, Minneapolis and
Toronto programs, as well as the fact that these programs have been
able to convince major global corporations to cooperate, lead us to
believe that this is a cause worth fighting for. We do not expect to
receive 100% cooperation immediately. However we do believe that 100%
participation is possible. This will be Washtenaw Audubon's ultimate
goal as we move forward with the program.
Before we can move forward, we must first identify a committee of
people who are willing to take the lead. Most importantly, we are
looking for an individual to spearhead this project under the
direction of Ray Stocking and with assistance from the Detroit Audubon
and Michigan Audubon Societies. If you are interested in chairing
this program, please contact Ray Stocking by email at
presidentATwashtenawaudubonDOTorg or by calling (734) 645-8110.
Others who wish to volunteer their time with this important project
are also encouraged to call or write. We look forward to hearing from
you and sharing details of this very exciting project. Look for
updates on Project Safe Passage in future publications.
If you are interested in knowing more about Safe Passage you may
review one of the websites listed below.
http://www.toronto.ca/lightsout/index.htm
http://www.cityofchicago.org/Environment/BirdMigration/
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Subject: [birders] Bird light attraction (was: Re: lights out in
Jackson)
From: eba(AT)umich.edu
Date: 3 May 2008 3:53pm
John or anyone,
Do you know specific references to work on the responses of birds to light?
I spent about a half-hour searching for references on the Cornell site, but
found rather little. Some work published a while back on birds hitting
residential windows, & a reference to a web site about Toronto
bird-building collisions, but rather little directly linking the fatalities
to lighting. In fact, eemed that the greatest number of bird collisions
comes when visibility is very poor, and it seems that the reason that was
given for that was largely conjecture. There were anecdotal references to
birds being "trapped" in strong beams of light such as searchlights
produce. The image of the birds spiraling to their deaths around a light
source seems to come from a hypothetical image rather than from scientific
research.
I did not find any statistics on numbers of birds killed in building
collisions in Toronto after lights were turned out to compare to the
mortality before that was done. Do you know if that data exists and is
accessible?
It seems that the problem is as much that the towers are in the way and
that it is harder to avoid them when visibility is poor. But one would
think if the birds were attracted to the light per se, that collision rates
would increase when visibility was good, because the lights would be
visible from a much greater distance. It may that they head for an area
where there is a diffuse glow when visibility is poor to try to improve
their ability to find their way around in those conditions, and that
unfortunately leads them to areas with concentrations of tall structures
which they could avoid better when they can see them from farther away.
More reliable data would do a lot to strengthen the argument. I'm all for
reducing light pollution, and unnecessary lights in tall buildings
contribute a lot to that, but if arguments for taking a certain action are
based on conjecture than on more reliable information, not only is the
action less likely to have the intended result, but the group which argued
for it in the first place becomes less credible.
I've seen the figure that 100 million birds die each year from collisions
with windows alone quoted as fact, but it seems that this is an estimate
that can be attributed to one "noted authority" and it seems that this is
among the highest estimates of bird mortality by this means out there. I
have also come across estimates in the 4 million range, which were not
attributed but which seemed to carry with them the implication that some
sort of data contributed to that number. I have no way of judging the
reliability of that information, either.
If these things are really known through reasonably careful work, then that
information needs to be more readily accessible. If it isn't really that
well known, then there's good reason to support research that will attempt
to provide more solid information, and that's likely to make any efforts to
reduce random, unnecessary bird mortality more effective.
Eric
--On Saturday, May 03, 2008 9:43 AM -0400 John Lowry <john(AT)kingbird.org>
wrote:
> Very well established. Just visit Cornell Lab of Ornithology website to
> learn about building collisions.
>
>
> On May 3, 2008, at 8:23 AM, eba(AT)umich.edu wrote:
>
>> Interesting.
>>
>> I had not been aware specifically that birds are drawn to light.
>> Perhaps it's just my ignorance; I'm certainly familiar with that
>> response in many insects, and I recall observing many years ago how
>> a large "garden toad" took advantage of this when I had a plant
>> light near a glass patio door -- the toad would would sit just
>> outside the door at night, and dinner would come to it. It was
>> really spectacular when the June bugs came out to see it zap one of
>> them!
>>
>> So for those of you who know more about this than I do, a question:
>> is it well established through good studies that this is indeed why
>> there are as many bird collisions with buildings as there are, or is
>> it conjecture from other experience? It would certainly help make
>> the argument locally if there is good research supporting this idea,
>> and if that hasn't been done yet, then it seems that it would be
>> good to do that.
>>
>> Eric Arnold
>> Ann Arbor
>>
>> --On Friday, May 02, 2008 11:09 PM -0400 Pat Burden
>> <tallerpat(AT)aol.com> wrote:
>>
>>> Thought this might be of some interest:
>>>
>>> http://tinyurl.com/5x5daf
>>>
>>> Pat Burden
>>> Yale, MI
>>>
>>> __________________________________________________
>>> Plan your next roadtrip with MapQuest.com: America's #1 Mapping
>>> Site. ---
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>>> birders_FAQ.html *
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>>
>>
>>
>>
>>
>> ---
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>> line. To
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>
>
>
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[ << | >> | ^^ ]
Subject: [birders] Re: Bird light attraction (was: Re: lights out in
Jackson)
From: "Ray Stocking" <rstocking(AT)gmail.com>
Date: 3 May 2008 4:00pm
Eric,
Google the following words: "cell tower collisions Joelle Gehring"
Hope this helps.
Ray
On Sat, May 3, 2008 at 3:53 PM, <eba(AT)umich.edu> wrote:
> John or anyone,
>
> Do you know specific references to work on the responses of birds to light?
> I spent about a half-hour searching for references on the Cornell site, but
> found rather little. Some work published a while back on birds hitting
> residential windows, & a reference to a web site about Toronto bird-building
> collisions, but rather little directly linking the fatalities to lighting.
> In fact, eemed that the greatest number of bird collisions comes when
> visibility is very poor, and it seems that the reason that was given for
> that was largely conjecture. There were anecdotal references to birds being
> "trapped" in strong beams of light such as searchlights produce. The image
> of the birds spiraling to their deaths around a light source seems to come
> from a hypothetical image rather than from scientific research.
>
> I did not find any statistics on numbers of birds killed in building
> collisions in Toronto after lights were turned out to compare to the
> mortality before that was done. Do you know if that data exists and is
> accessible?
>
> It seems that the problem is as much that the towers are in the way and
> that it is harder to avoid them when visibility is poor. But one would
> think if the birds were attracted to the light per se, that collision rates
> would increase when visibility was good, because the lights would be visible
> from a much greater distance. It may that they head for an area where there
> is a diffuse glow when visibility is poor to try to improve their ability to
> find their way around in those conditions, and that unfortunately leads them
> to areas with concentrations of tall structures which they could avoid
> better when they can see them from farther away.
>
> More reliable data would do a lot to strengthen the argument. I'm all for
> reducing light pollution, and unnecessary lights in tall buildings
> contribute a lot to that, but if arguments for taking a certain action are
> based on conjecture than on more reliable information, not only is the
> action less likely to have the intended result, but the group which argued
> for it in the first place becomes less credible.
>
> I've seen the figure that 100 million birds die each year from collisions
> with windows alone quoted as fact, but it seems that this is an estimate
> that can be attributed to one "noted authority" and it seems that this is
> among the highest estimates of bird mortality by this means out there. I
> have also come across estimates in the 4 million range, which were not
> attributed but which seemed to carry with them the implication that some
> sort of data contributed to that number. I have no way of judging the
> reliability of that information, either.
>
> If these things are really known through reasonably careful work, then that
> information needs to be more readily accessible. If it isn't really that
> well known, then there's good reason to support research that will attempt
> to provide more solid information, and that's likely to make any efforts to
> reduce random, unnecessary bird mortality more effective.
>
> Eric
>
> --On Saturday, May 03, 2008 9:43 AM -0400 John Lowry <john(AT)kingbird.org>
> wrote:
>
>
> > Very well established. Just visit Cornell Lab of Ornithology website to
> > learn about building collisions.
> >
> >
> > On May 3, 2008, at 8:23 AM, eba(AT)umich.edu wrote:
> >
> >
> > > Interesting.
> > >
> > > I had not been aware specifically that birds are drawn to light.
> > > Perhaps it's just my ignorance; I'm certainly familiar with that
> > > response in many insects, and I recall observing many years ago how
> > > a large "garden toad" took advantage of this when I had a plant
> > > light near a glass patio door -- the toad would would sit just
> > > outside the door at night, and dinner would come to it. It was
> > > really spectacular when the June bugs came out to see it zap one of
> > > them!
> > >
> > > So for those of you who know more about this than I do, a question:
> > > is it well established through good studies that this is indeed why
> > > there are as many bird collisions with buildings as there are, or is
> > > it conjecture from other experience? It would certainly help make
> > > the argument locally if there is good research supporting this idea,
> > > and if that hasn't been done yet, then it seems that it would be
> > > good to do that.
> > >
> > > Eric Arnold
> > > Ann Arbor
> > >
> > > --On Friday, May 02, 2008 11:09 PM -0400 Pat Burden
> > > <tallerpat(AT)aol.com> wrote:
> > >
> > >
> > > > Thought this might be of some interest:
> > > >
> > > > http://tinyurl.com/5x5daf
> > > >
> > > > Pat Burden
> > > > Yale, MI
> > > >
> > > > __________________________________________________
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Subject: [birders] Non-Bird, "Polarized Light"
From: Fred Kaluza <fkaluza(AT)yahoo.com>
Date: 3 May 2008 1:12pm
I think you meant "specular" and not "secular" but
thanks. Nice explanation.
-----Original Message-----
From: eba(AT)umich.edu [mailto:eba(AT)umich.edu]
Sent: Saturday, May 03, 2008 2:11 PM
To: birders(AT)umich.edu
Subject: [birders] Polarized light and basic physics
Light doesn't reflect off of molecules, it scatters.
Scattering is the word physicists use to describe the
interaction of light or other physical waves from
objects which are generally smaller than a wavelength,
and the resulting scattered waves tend to go in all
directions, although not necessarily with equal
amplitudes or other physical properties, of which
polarization is one.
When a surface is smooth, and by smooth we mean that
it is pretty uniform without bumps or wrinkles or
other departures from a plane or smoothly curved
surface that are comparable in size to a wavelength,
then we can get secular, or mirror-like, reflection
from these surfaces. If the smooth area is large
enough, we can get a visually-detectable reflection
which looks like an independent light source.
If the material has the property of being dielectric
at the frequency of the wave motion, then the
reflected wave can also be polarized. However, the
degree of polarization depends crucially on the angle
at which the wave strikes and leaves the surface, and
for the principal reflection, i.e. the brightest one,
the angle of incidence equals the angle of reflection,
just like in a mirror. At a certain angle of
incidence & reflection the polarization is greatest,
and can be a high fraction of the total reflection,
depending on the exact nature of the reflecting body.
At other angles, the polarization is less complete; as
bird's view of an object giving polarized light by
reflection changes, the degree of polarization it
would be able to see would change very much, so it
would be hard to explain a spiraling phenomenon on the
basis of polarization because it wouldn't stay in the
polarized beam unless it were heading straight for it
in the first place, and the use of light sources as
navigational aids doesn't generally involve heading
for them so much as keeping it at a relatively
constant angle, at least for a fraction of the day or
night. But even if a bird tries to keep a reflected
polarized source at a fixed angle, it would see
changing polarization as its position relative to the
reflecting object changed. It's hard to imagine that
reflections from relatively small objects would be
more than noise sources in overall patterns of
polarization that a bird might detect. They would
simply mingle in with lots of other noise sources, I
suspect, coming from lots of other objects whose light
is polarized to varying degrees, and that includes
leaves -- ask a photographer who uses a polarizing
filter if it's just water, sky, and shiny non-metallic
(i.e. dielectric) objects that are affected, and
you'll find out that there are lots of other things
that are affected to a degree, too, although the
details of the effect are much less easily predicted
than with the sky and the discrete reflections from
large smooth objects.
Moonlight isn't polarized to any significant degree
because its surface isn't smooth enough, and that is
true for many other more-or-less amorphous substances
like rocks which haven't been worn smooth.
Reflections from metallic objects don't generally
result in polarized reflections from non-polarized
light sources, but they can pass on the polarization
of incident light which was already polarized, whereas
reflected light from rough surfaces looses its
polarization even when the illuminating light is
strongly polarized.
Eric Arnold
--On Saturday, May 03, 2008 12:48 PM -0400 Bruce
Robertson <roberba1(AT)msu.edu> wrote:
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Subject: [birders] Some Notables At My Feeder Today
From: <David.Blank(AT)lyondellbasell.com>
Date: 3 May 2008 4:14pm
----INCLUDING text/plain MIME SECTION----
Two male Rose-Breasted Grosbeaks and one male Baltimore Oriole. Also,
house wrens are scoping out a couple of residences. =20
=20
David Blank
Barton Hills
=20
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Subject: [birders] grosbeaks
From: "Sally K Scheer" <winerat(AT)villagecorner.com>
Date: 3 May 2008 4:40pm
Have had a male rose breasted grosbeak for about 4 days now. Today the
female made an appearance. The male fed at the tubular black oil sunflower
feeder while the female whacked away at the suet feeder. Then se came to the
seed feeder with the male on a lower level and she on the upper level. When
she decided to hit the lower level too, he flew off. Nice to have them again
this year. They're right on time.
Better get the jelly plate out for the baltimore orioles. They usually
appear about the time the elm seeds start falling and those seeds have been
all over today.
Sally Scheer
Clinton MI
Bridgewater Township
SW Washtenaw County
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