Utah County Birders Newsletter
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Contents
November Meeting
Upcoming Field Trips
President's Message
Bird of
the Month
Field Trip Report - The Big Sit!
Website Report
Backyard Bird of the Month
October Hotline Highlights
NOVEMBER MEETING:
Thursday, November 10th.
We are going to have a custom tour of the private
Hutching's Natural History Museum in Lehi.
Meet at the Bean Museum at 6:50pm sharp if you want to car pool, or at the
Hutching's Museum, 51 North Center in Lehi, if you live in the north end of the
county at 7:30pm. The tour will be lead by Jim Thorn, an avid birder himself,
and will include a detailed look at the bird collections. The museum normally
closes at 5:00pm, so they are making a special effort to accommodate our evening
tour, so let's all make an effort to come out and support our club. Cost is
$4.00/adult, $3.00 for seniors. It will be a very informative, educational, and
interesting evening.
Beginning birders are welcome.
November 12 (Sat): 7am-late afternoon. AIC Causeway and mountain reservoirs "Loon Loop". - Led by Keeli Marvel. We will meet at southwest end of the Orem WinCo parking lot (895 North 980 West in Orem - just east of the 800 North Orem freeway exit) - at 7:00am. We'll hit the causeway first to see if any scoters, long-tailed ducks, or harlequin ducks are around, and then head up Ogden canyon from there. Stops may include East Canyon, Echo, Rockport, Jordanelle, and Deer Creek Reservoirs depending on time/weather.
December 17 (Sat):
Provo Christmas Bird Count -
Assignments are given out at the Utah County Birders meeting on December 8th. If
you can’t attend the meeting, call Dennis Shirley at 801-491-4084 or send an
email to bt_shirley@hotmail.com .
We are actively recruiting people to lead local half-day field trips, any time,
any place. If you would like to lead a field trip or if you have any ideas for
this year’s field trips, please contact Keeli Marvel at - keeli.marvel@gmail.com.
by Bryan Shirley, UCB President
Surviving
Winter
A couple of days ago we got a nice snowstorm. At my house in Payson we had about
3 inches of snow. The snow and cold temperature led to a discussion with my wife
about how the quail in my parents’ yard were going to survive the winter. I
started to explain some ways that birds stay warm, most of which I had learned
in an article in the Utah County Birders Newsletter a few years ago by Merrill
Webb. This is such a great article that I decided to reprint it this month. In a
couple of months when you are sitting in your car on the causeway because it is
too cold to get out and set up a scope this article will help you appreciate how
the birds survive.
Merrill's Musings
By Merrill Webb
Adaptations to the Cold
During this last week I decided to drive down to where the Provo River flows
into Utah Lake to see what (if any) birds were on the water. There were coots on
the water and gulls on the ice. It was very cold and there wasn't much open
water, in fact the harbor was frozen solid. Ring-billed Gulls on the ice--and on
the ground. Only Ring-billed, no Herring, no California--just gulls on the ice
and on the frozen ground. Some standing on one leg, others just sitting on that
cold ground and cold ice. And they seemed perfectly contented. If they had been
cows they would have been chewing their cud. No frost bite. No frozen
extremities.
'Wait a minute,' I thought. 'How can they do that and not suffer any visible ill
effects?'
Two days later at school my principal asked me (like others ask you, since they
know you are interested in birds and are therefore the "authority", at least
where you work). "What do birds do to survive this terribly cold weather? How
can they possibly survive?"
I was ready (since a couple of days previously I had researched the problem--at
least as it pertained to gulls); but when I was finished providing an answer he
had kind of a glazed look in his eyes. 'Overkill' I realized. He only wanted to
tell me about the birds in his back yard, "finches," he called them, and what
they were eating to survive. He didn't really want to hear me pontificate, it
was just an opportunity to share what he had observed about the birds that were
important to him.
So, at the risk
at having your eyes glaze over, too, I am going to share some of the interesting
adaptations to cold that I have learned about birds, both from observation and
reading. After all, it is going to be my philosophy that this column can, and
should be, educational as well as conversational.
Birds have the ability to maintain a high and constant body temperature that
enables them to exploit a remarkable range of habitats. If the ambient
temperature falls, birds raise their metabolic rate to prevent their internal
temperature from falling.
Crossbills are highly cold resistant, as you might expect. When roosting in the
boughs of evergreens during severe cold, the dominant birds secure places
deepest in the thicket. That leaves the least dominant birds closer to the wind.
More exposed and with less fat reserves, they are the first to die on the
coldest nights. The fat that helps to insulate this species can now be used to
generate warmth through a process called catabolism, the destructive part of
metabolism in which the breakdown of fatty substances, triggered by hormones and
muscular activity, releases energy in the form of heat.
So, the birds start to shiver in their sleep. A muscle used in raising a wing
and an opposing muscle used in lowering it begin to contract in rapid rhythm
against each other; thus each is exercised while the wing remains unmoved. So
also do opposing sets of muscles tug at each other from head to tail, causing
all of the body to quiver. This is catabolism at work, and body heat is boosted
at once.
Nonmigratory birds like the cardinal stores fat in sequence, building up
deposits in different parts of its body over a period of time. First, fat is
laid down in the neck pouch between the breast muscles. When this is full, a
thin layer of fat overlays the abdomen. Next come deposits under the wings. By
this time fat encircles many of the internal organs as well. In this manner the
cardinal seems to buy time through the early weeks of the winter season, keeping
as trim as possible so it can speed away from predators.
The cardinal carries about three days of reserve fat, enough to see it through
the time that an average ice storm or blizzard would hinder its food hunting. If
the cardinal cannot eat by the fourth day it will begin to starve. It cannot
maintain metabolic functions. Body temperature begins to fall. Death follows
swiftly.
Chickadees, accustomed to bitter cold, respond with another life-saving
adjustment. They shorten their foraging days. Or in particularly harsh weather,
they stay in their roosts. They also conserve precious energy at night when
their body temperatures may drop from 104 degrees F to 84 degrees F. They take
in less food in a shorter hunting day, but they use their fat reserves at a
lower rate and so have a better chance of outlasting the freeze.
Birds that overwinter in cold regions have evolved specialized insulation and
respiratory systems, which serve two vital purposes: to keep the cold out and to
enable the organs to function as a hot core. The legs of the Willow Ptarmigan
are covered with feathers to reduce heat loss. Many birds, such as the redpolls
of Alaska, have more feathers in winter than in summer; their feathers weigh 31%
more in November than in July.
Ptarmigan and other grouse acquire a fringe of scales along each toe, which
enlarges the surface area of the foot. The ptarmigan have gone further to
increase the surface area of their feet: in winter plumage, they develop highly
modified dense feathering covering both surfaces of their feet, and their claws
become significantly longer (avian snowshoes). Experiments using feathered and
plucked ptarmigan feet on soft snow clearly demonstrate that foot feathering
eases walking in these birds much the way snowshoes aid people. The feathers
increase the bearing surface of the foot by about 400 percent and reduce the
distance the foot sinks in snow by roughly 50 percent.
In order to escape the cold, birds as large as ptarmigans and as small as Snow
Buntings may burrow into loose snow to sleep. Two feet down in the snow the
temperature can be 25 degrees F when the air above the snow is colder than -50
degrees F.
One of the most important adaptations enabling redpolls and crossbills to cope
with the energy demands imposed by severe arctic and subarctic winters is a
structure that is somewhat analogous to the substantial crop of gallinaceous
birds. The structure is a partially bilobed pocket situated about midway down
the neck, technically an "esophageal diverticulum." The pocket is used to store
seeds, especially toward nightfall and during particularly severe weather.
The "extra" food helps carry the bird through low nighttime temperatures, and
permits energy to be saved during bad weather by reducing foraging time and
allowing the bird to "feed" while resting in a sheltered spot.
In addition, redpolls and crossbills seek the wind-protected shelter provided by
dense coniferous foliage, remain stationary, and adopt a "fluffed-ball" posture
that further enhances their insulation and thus reduces heat loss.
When it is cold, the lack of insulation on the legs makes them a site of
potential heat loss. To minimize such loss, special blood vessels, the arteries
and veins in the legs of many birds (gulls and waterfowl, for example), lie in
contact with each other and function as a countercurrent heat exchange system to
retain heat. Arterial blood leaves the bird's core (trunk) at body temperature,
while venous blood in the bird's foot is quite cool. As the cool blood returns
toward the core, heat moves by conductance from the warm arteries into the cool
veins. Thus, arterial blood reaching the feet is already cool and venous blood
reaching the core has already been warmed. In addition, by constricting the
blood vessels in its feet a bird may further decrease heat loss by reducing the
amount of blood flow to its feet at low temperatures. Thus while the core
temperature of a duck or gull standing on ice may be 104 degrees F, its feet may
be only slightly above freezing.
By standing on one leg and tucking the other among its breast feathers, a duck
or gull on ice reduces by half the amount of unfeathered limb surface area
exposed; by sitting down and thus covering both legs, heat loss from the limbs
is minimized. In cold weather, juncos, sparrows and other finches foraging on
the ground frequently drop down and cover their legs and feet with their breast
feathers while pausing in their search for food.
Last November I was walking along the Virgin River Trail south of St. George.
The weather was unseasonably cool. I observed a roadrunner with its back to the
sun and its feathers all "puffed up" showing a very dark interior. I found out
the following: Dark pigmentation aids temperature regulation by absorbing the
energy-rich short wave lengths of the solar spectrum. When rewarming from mild
overnight hypothermia, the Greater Roadrunner erects its scapular feathers and
orients its body so that the morning sun shines on strips of black-pigmented
skin on its dorsal apteria.
Probably all of us have observed Red-winged Blackbirds flying into the cattails
along the Utah Lake shoreline to roost. Birds that roost communally crowd
together at night during the winter to keep warm. Some studies have reported
that the older blackbirds are concentrated in the centers of their roosts while
the younger birds are situated around the periphery, more exposed to predators.
However, there is a drawback to communal nesting. There is some evidence that
birds in the lower positions in colonial roosts lose heat because the rain of
droppings from higher birds reduces the insulating properties of
their plumage.
It has been observed that small groups of nuthatches or creepers spend the night
together in tree cavities to significantly reduce their heat loss.
And finally, I found this interesting tidbit about Saw-whet Owls. Their diet is
mainly small rodents; but they also take insects. They sometimes cache their
dead prey items in the snow. Later, they will assume an incubating posture to
thaw frozen prey.
So, my suggestion is that during this winter when there seems to be a paucity of
birds to watch, take time to observe the temperature- regulating actions,
especially those of shorebirds and gulls. They are the most readily observed and
interpreted of bird behaviors.
Sources:
The Birder's Handbook 1988, by Paul Ehrlich, David Dobkin and Darryl Wheye;
The Wonder of Birds, 1983 National Geographic Society;
Ornithology, 1989, by Frank Gill
Bird of the Month
No Bird of the Month this Month.
If you would like to write an article for the Bird of the Month, please contact Oliver Hansen -- 801-378-4771 - byucactus@gmail.com .
Click here for past 'Birds of the Month'.
Field Trip Report
The Big Sit! - Provo Airport Dike - October 9, 2011
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Start of our big day. Dawn at our Big Sit Circle- looking East |
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End of our big
day. Lyle watching the Sunset. |
by Eric Huish
The Big Sit - Provo Airport Dike -
9 October 2011
The Provo Airport Big Sit was covered nearly continuously from 6:10 am to 8:00
pm. 12 hours total time where at least one person was there. This was our 10th
year participating in the big sit. We sat at the Southeast Corner of the dike
loop, where the moat does a 90° turn to the west. We spent the day sitting
within a 17 foot circle. We were able to see or hear 56 species from our circle
this year. Our record is 58 species in one day (2007) and our 10 year (10 day)
Big Sit Life List is now at 113 species. We added 6 Big Sit Lifers this year -
Horned Grebe, Great Egret, Common Nighthawk, Vaux's Swift, Western Wood-Pewee
and Warbling Vireo.
The Vaux's Swift was the rarest bird. Around 10:30 am we started seeing flocks
of Barn Swallows and Tree Swallows flying past/over us heading south. While
scanning the swallows, hoping for a third swallow species, we were excited to
see a Vaux's Swift fly past. It flew by pretty close and we got a good look at
it but It didn't stick around.
The Horned Grebe hung out in the moat near our sit circle all day.
The Western Wood-Pewee was hanging out around the telephone wires North of our
sit circle and would occasionally give a faint call.
I saw a Common Nighthawk flying close to the sit circle very early in the
morning while it was still pretty dark out.
A flock of Mountain Bluebirds spent the morning hunting over the old runway in
the southeast corner of the airport.
We spotted 2 Great Egret and 14 Snowy Egrets flying way out over the marsh to
the east us in the evening. They were far away but we had great lighting with
the sun low at our backs, we could the the yellows of their feet.
Our last bird of the day was a Barn Owl that flew over after we briefly played a
call.
Water levels were high this year so we didn't have a mud flat. We only saw 1
shorebird all day, a single killdeer flew over.
Time At Location: 12 Hours --- 6:10 AM - 12:05 PM, 1:00 PM - 3:45 PM and 4:40 PM
- 8:00 PM. Sit participants were Eric Huish, Milt Moody, Lyle Bingham, Keeli
Marvel, Alona Huffaker and two of her granddaughters, and Ned Bixler took a lone
afternoon shift from 1:00 to 3:45. Thanks Ned!
Here is our species list -
Canada Goose
Gadwall
Mallard
Ring-necked Pheasant
Pied-billed Grebe
Horned Grebe
Western Grebe
Clark's Grebe
Double-crested Cormorant
Great Blue Heron
Great Egret
Snowy Egret
Black-crowned Night-Heron
White-faced Ibis
Northern Harrier
Cooper's Hawk
Red-tailed Hawk
Golden Eagle
American Kestrel
Virginia Rail
Sora
American Coot
Sandhill Crane
Killdeer
Ring-billed Gull
Caspian Tern
Eurasian Collared-Dove
Mourning Dove
Barn Owl
Common Nighthawk
Vaux's Swift
Belted Kingfisher
Northern Flicker
Western Wood-Pewee
Warbling Vireo
Black-billed Magpie
Tree Swallow
Barn Swallow
Black-capped Chickadee
Marsh Wren
Mountain Bluebird
American Robin
European Starling
American Pipit
Cedar Waxwing
Orange-crowned Warbler
Yellow-rumped Warbler
Chipping Sparrow
Song Sparrow
White-crowned Sparrow
Red-winged Blackbird
Western Meadowlark
Yellow-headed Blackbird
Brewer's Blackbird
House Finch
American Goldfinch
Utah Birds Website Report
by Milt Moody
There have been a few changes to our website. We've added bird and place photos
to a lot of the pages -- most of them clickable. Because the "Photo Gallery" is
one of the most popular "spots" on the website (and one of the most valuable),
there's a new prominent link through an extra wide graphic (photos of a Western
Tanager, a Burrowing Owl and some American Avocets) which takes you to a
spruced-up index with clickable thumbnails as examples of the different bird
groups. There are presently over 19,000 photos of about 450 bird species --
males, females, juveniles, flying, close-ups, action shots, etc. We've got a lot
of views and plumages you can't find in the field guides -- a good place to
study the birds. Thanks to the photographers and other who are helping with
information and content we're building up on the website.
Thank you to those who have gone through our "Amazon" link to buy things. This
year we are in line to receive enough Amazon funds to pay for the yearly
web-hosting expenses -- we've usually received about half that in years past. I
noticed that Consumer Reports rated Amazon as one of the best "places" to buy
computers, so it's a good place to check, but if you can get things cheaper
elsewhere, that's the best thing to do. Anyway, your help is much appreciated.
Thanks to Leena Rogers for her "Hotline Highlights" reporting and to Eric Huish
for the Utah County Birders pages (including posting the newsletter), the State
Calendar, and for many other miscellaneous things he does for the website.
The website is getting better and better all the time.
Backyard Bird of the Month
October 2011
Bruce
Robinson - West Jordan
Dark Eyed Junco - First of the season in the yard
Milt Moody - Provo
A Ruby-crowned Kinglet flitting in my wild rose bush
Eric Huish - Pleasant Grove
On Oct 9th, in just 30 minutes of watching the sky over the backyard, I saw 30
Red-tailed Hawks, 5 Turkey Vultures, 4 Sharpies, 2
unidentified Accipiters and an Osprey.
Steve Carr - Holladay
Downy Woodpecker - A pair of them come and go to the peanuts and peanut
butter feeders several times a day all winter long.
Cheryl Peterson - Provo
I am always happy to see a Downy Woodpecker in the tree outside my
window. The Dark-eyed Juncos are daily visitors again.
Dues
Thanks to all who have supported us in the past. If you are interested in
officially joining
us this year, make out a check to Utah County Birders for $15.00 and mail it to:
Carol Nelson
2831 Marrcrest West
Provo, Utah 84604
You will be helping to support the web page and we will send you a copy of the
newsletter.