Monday, March 31, 2008

Adopt A Bird spotlight: Lewis


Lewis's Story

Species: Bald Eagle
Hatched: Spring 2002

Lewis was wild hatched in Washington state. At a very young age he fell out of his nest tree, injuring his hip and leg. He was brought in to a rehabilitation center in Washington, where he received intensive treatment for his injuries over an extended period of time. Though he survived his injuries, he did not regain full use of his foot and would not be able to survive in the wild.

Lewis arrived at the World Bird Sanctuary at the age of one year and, after careful training, has become a well known ambassador for his species. If you are a Cardinals baseball fan, you have probably seen Lewis at one of the Cardinals games. He is the majestic bird that flies to the pitcher's mound after the National Anthem. Lewis has performed at countless other special events and is a favorite of many of our visitors. If you'd like to see Lewis in action, check out the post from March 12th, which includes a video of Lewis practicing his flight!

To adopt Lewis, simply click our donation button, make a donation of $150, and specify in your payment notes: Adopt-a-bird: LEWIS. Also include your name, phone number, and mailing address so that we can send you your adoption materials!

Every donation helps to feed, house, and provide medical care for the bird of your choice! Adopt-A-Bird Parents Receive:

  • *A personal visit with the bird you adopt!!!!! Call 636-861-3225 to set up a time for
  • your personal visit.
  • * Certificate of Adoption
  • * Color photo of the bird you've adopted
  • * Sponsorship Card
  • * One year's subscription to Mews News (our quarterly newsletter)
  • * Life History and Natural History of the bird
  • * 10% Discount off WBS merchandise
  • * Invitation to Sponsors-only events like Camera Day
  • * Discounts on WBS Special Events
  • * WBS Decal

Natural History

Bald Eagle
Haliaeetus leucocephalus

Description: large; white head, neck and tail; brown-black body; massive yellow bill and feet

Sex: males and females are similar but females are larger

Age: juveniles are mostly dark brown with white blotches underneath and on the wing linings; become more white each molt; gain adult plumage after 4-5 years; immature calls are generally harsher

Length: 31-37”

Wingspan: 5.8-7.5’

Weight: 8-14 lbs.
Habitat: rivers, lakes, coastal areas

Status: seen across most of North America; common in Alaska, parts of Florida and in the Midwest during winter months; common along the Mississippi and Missouri Rivers in winter; became endangered in the 70s from pesticides; conservation programs and pesticide banning helped increase populations again

Range: Alaska and Canada to the southern United States

Behavior: monogamous pairs; breed April-August and build a stick nest as high as 150 feet above the ground, usually in a tree or on cliffs near water; renovate and add to their nest each year until it falls; 1 brood with 1-3 dull, whitish eggs; both parents incubate for 34-36 days until semi-altricial chicks hatch asynchronously; chicks leave nest at 10 weeks; large numbers of bald eagles often congregate where food is plentiful, like spawning ruts; will steal food from smaller and weaker osprey; fly low after prey
Diet: carrion, fish, waterfowl, birds, small mammals

Vocalization: sharp, pleading, creaking cackle; “kleek-kik-ik-ik-ik”; lower “kak-kak-kak”

√ The bald eagle has been the national symbol of the United States since 1782


Monday morning haiku...

Today’s poem was inspired by Tema, our sometimes alarmingly intelligent Augur Buzzard.

Tema: the happy
Captain of the sunshine squad
Showcasing talons.



For more information on augur buzzards, see the March 5, 2008 post and video.

Sunday, March 30, 2008

How they grow…

Tawny Owl
Family Strigidae, Strix aluco

Tawny owls are medium sized owls found in Europe and Asia. They prefer to live in woods and open areas with large trees for perching. Their call is the famous "to-Wit, to-Woo."

With the loss of much of their rural habitat, tawny owls are moving into cities and suburbs. Their hunting techniques have changed with their new environment. One new technique involves landing on a branch and then slowly walking sideways along the limb until it is next to a sleeping songbird. One quick snatch, and the owl has a meal! Pretty sneaky…

These pictures chart the growth of tawny owl chicks from 7 to 64 days. They were taken by our friend and photographer Gay Schroer. Hmm…which is cuter, the tawny owl or the Eurasian eagle owl? (see post: March 23rd )


7 days

30 days


43 days


58 days

64 days

Saturday, March 29, 2008

Adopt A Bird spotlight: Aspen

Starting today, I’ll be featuring a bird from our "Adopt-a-bird" program. Each post will include the individual bird’s story and a natural history of the species. Adopt-a-bird is a fun way to donate to the sanctuary. Every donation helps to feed, house, and provide medical care for the bird of your choice! Adopt-A-Bird Parents Receive:

* * Certificate of Adoption
* * Color photo of the bird you've adopted
* * Sponsorship Card
* * One year's subscription to Mews News (our quarterly newsletter)
* * Life History and Natural History of the bird
* * 10% Discount off WBS merchandise
* * Invitation to Sponsors-only events like Camera Day
* * Discounts on WBS Special Events
* * WBS Decal
* *A personal visit with the bird you adopt!!!!! Call 636-861-3225 to set up a time for your personal visit.

To adopt today’s bird, simply click our donation button, make a donation of $50, and specify in your payment notes: Adopt-a-bird: ASPEN. Also include your name, phone number, and mailing address so that we can send you your adoption materials!



Aspen’s story

Species: Northern Saw-whet Owl
Age: Unknown

Aspen was brought to our Rehabilitation Hospital after sustaining injuries due to a vehicle collision in the Hillsboro area. She had severe injuries to her right wing and shoulder. After three months of intensive treatment she was again healthy, but unable to fully extend her injured right wing. Because of this, she is unreleasable. It was decided that even though she can’t be returned to the wild, she can be a spokesbird for her species at the World Bird Sanctuary’s Office of Wildlife Learning. Though people have begun referring to Aspen as female, we do not really know the sex. The only way we can be certain is if we have the bird surgically sexed or if an egg is laid.

Because Aspen was already fully mature when we received her, she is still wary of humans, and is being allowed to slowly acclimate to the humans she will encounter as a display bird. If you visit Aspen in the near future, you will notice that she has a partial privacy screen around her enclosure so that, if she is feeling stressed by too much human contact, she can retreat to an area where she feels comfortable. The adoption donation for Aspen is $50.00.


Natural History

Northern Saw-whet Owl
Aegolius acadicus

Description: very small, short-bodied owl; relatively short tail; overly large head has no ear tufts; facial disk has brownish and whitish radials around the edge, which fade to a whitish area around the eyes; a dark area from the base of the bill extends to the bottom inside edge of each eye; rest of the head is brownish to grey-brown densely covered with white streaks, especially on the forehead; eyes are large and bright yellow-orange; bill is black; fluffy plumage is brownish overall, streaked with white underneath and spotted on the back; flight feathers are spotted white; legs and feet are light buff and heavily feathered; toes are lightly feathered; claws are dark horn with blackish tips;

Sex: females slightly larger than males, otherwise identical in appearance

Age: 8 years in captivity; high mortality in the wild

Length: 6.7-8.6” Wingspan: 18-22” Weight: 2.6-3.9 oz.

Habitat: coniferous and deciduous forests with thickets of second-growth or shrubs; breeding habitat usually swampy or wet
Status: not endangered; locally frequent

Range: southeast Alaska to Mexico in the west; from the west coast of southern Canada to the east coast of the northern U.S.; winter range covers most of the Midwestern U.S. from the Rockies to the east coast;

Behavior: strictly nocturnal; roost in foliage during the day, usually close to the ground; flight is rapid, woodpecker-like, and undulating; pair bonds are not believed to be permanent; males stake out territory in late March-April; once a female has been attracted, he will fly in circles above her while calling; then he begins a complex series of bobbing and shuffling; he may offer her a mouse; nests are usually in old woodpecker cavities; nesting occurs between March-July; clutch size ranges from 3-7 eggs; female does all the incubation; young fledge at 4-5 weeks and are cared for by parents for some weeks; sexually mature at 9-10 months.

Diet: feed almost entirely on mammals, primarily mice, shrews and voles; other prey may include squirrels, moles, bats, small birds, and occasionally frogs and insects;

Vocalization: vocalizes during breeding season only; courtship call is a monotonous, whistled “hoop”, emitted at about 1.5 notes per second; this owl’s name comes from the “skiew” call made when alarmed; when the male flies to the nest with food it gives a rapid staccato burst of toots, and female answers with a soft “swEE”

Friday, March 28, 2008

Molting in Songbirds

Today's post is written and photographed by our volunteer, Daniel. Thanks Daniel!

Molting is a complex procedure that all birds go through at various
times in their lives. It’s the process of shedding damaged or dull
feathers, to be replaced with feathers appropriate to the time of
year and the sex of the bird. At the beginning of breeding season,
the males of some species of songbirds go through a large molt into
their breeding plumage. They do this to compete with other males of
the same species for possible mates. American Goldfinches,
Bobolinks, Indigo Buntings, Scarlet Tanagers, and most warblers, are
the most well known for their drastic color changes.

Here is a series of pictures showing the molting process of male
American Goldfinches into breeding plumage. These pictures were
taken over this past winter in my backyard.









For further reading on molting, visit the Cornell Lab of Ornithology
web site at www.birds.cornell.edu

Thursday, March 27, 2008

Who's on eggs...again?

This video, recorded on March 26, 2008 during a nest box check, shows that our barn owls are at it again! We left some of the babies with Athena and Sonar, but they have started a second clutch anyway. Here are the older babies and Athena's 6 new eggs:

Wednesday, March 26, 2008

How they grow...African Pied Crow

Family Corvidae, Corvus albus

This crow is about the same size as our American Crow, but their black and white coloring makes them distinct. Like their raven relatives, pied crows can be very playful. An acquaintance from Zimbabwe once told me that he enjoyed watching them slide down windshields in a parking lot where he worked. They would fly back up to the top of the car and do it again and again. Pied crows love attention and make wonderful education birds. They can learn to mimic up to 100 human words and 5 phrases!

The following pictures record the growth of a pied crow from 7 to 28 days. They were taken by our friend and photographer Gay Schroer. For me, they fall into the “so ugly they are cute” category.


7 days


22 days


28 days


28 days

Tuesday, March 25, 2008

More spring cleaning...

White-naped Raven
Family Corvidae, Corvus albicollis

At 20 inches tall with a 3 foot wingspan, the white-naped (sometimes known as white-necked) raven is a large bird. In their native region of Africa (eastern edge of the continent from South Africa to Zaire), they are often mistaken for hawks. Like ravens worldwide, they are famous for their intelligence and frequently found playing the role of "trickster" in native mythology.

White-naped ravens are social birds. In non-breeding season, they form flocks of up to 150 members. A group of ravens is known as an "unkindness," a "constable," or a "conspiracy." The singular raven in this video is know as Mischief, Slayer of Broom.


Sorry for the shaking. I am trying to sweep, film, and maintain broom-control all at the same time!

Monday, March 24, 2008

We survived the flood!

The World Bird Sanctuary is located on the 500 year floodplain of the Meramec River in Valley Park, Missouri. In late March of 2008, the river was predicted to hit record levels, surpassing the disastrous flood of 1982. Many homes and businesses along the Meramec, particularly in Pacific, Eureka, Valley Park, and other towns along the floodplain, saw devastating destruction. Our thoughts and best wishes are with them.

The following videos were taken between our evacuation on Friday, March 21st and Sunday March 23rd, after the river crested two feet below the predicted level. Those two feet and your help and donations helped us weather the flood. Thank you!

We moved over 100 birds on Friday, March 21st when flood water hit our property. As a precaution, we emptied our lowest lying building where most of our exotics are housed. Dr. Stacey Schaeffer brought out her horse trailer to move the parrots and cages. All animals are OK and were moved back after the river crested on Saturday.



Recorded on March 23, 2008 using a Flip Video camcorder. The first two clips are going west on highway 44. Sandbags and concrete barriers to the side are holding the water off 44. Under all the water is the outer road that leads to the World Bird Sanctuary. The last clip is highway 141 at 44 intersection:



This video was taken at the World Bird Sanctuary's lower site:

Sunday, March 23, 2008

Owls grow up too fast!

** First this morning, I want to say thank you to all of our friends and readers who donated and offered their time to help us recover from the flood. The Meramec River reportedly crested at 38 feet yesterday, two feet lower than what had been predicted, and I'm keeping my fingers crossed that we managed to escape the worst. I will post an update as soon as I know the extent of the damage. On a cheerier note: Eurasian Eagle Owls! These fantastic creatures are just one example of what your support makes possible. Thank you.

If there were an international cuteness award for baby raptors (and there should be!) I think the Eurasian Eagle Owl (EEO) would win every year. The EEO is one of the largest owls in the world, standing 24-28 inches tall with a wingspan in excess of 5 feet! In England, these owls were persecuted to near extinction in the late 19th century. The oldest recorded eagle owl lived to be 68 years old. An eagle owl weighing 6.5 - 8.5 pounds can take prey as large as a roe deer weighing 28-30 pounds.

In the wild, this owl is an accomplished hunter, dieting primarily on mammals but extending their menu to include fish, birds, reptiles, and even insects when need be. They catch their prey in the air, on the ground, or even plunging into water! During the first half of the 20th century, Eurasian eagle owls saw tremendous declines in population due to habitat loss, persecution, disease, and poisoning. Even today, many of us use poison to kill rats and other household pets, without realizing we are also killing those very animals that help keep pest populations under control!

Thanks to efforts including education and re-introduction, EEOs have made a partial recovery in Europe.

These pictures chart the growth of Eurasian Eagle Owl chicks at WBS from 11-77 days. They were taken by our good friend and talented photographer Gay Schroer:

11 days old

14 days old


17 days old


34 days old


48 days old

77 Days (check out those big feet!)

For more information on EEOs, check out www.peregrinefund.org, which was a valuable source for this post.

Saturday, March 22, 2008

The flood

As some of you know, the World Bird Sanctuary is located in Valley Park, MO, where the Meramec River is expected to peak today at 40 feet. The lower site, which is where most of the birds on this blog are housed, has been evacuated. Though the birds and people are safe, clean-up could be expensive. Everyone who can is pitching in. I don't have photos or video of the flood, but those who are interested can find a video of the evacuation by clicking on this link:

Link

Please keep us in your thoughts.

Friday, March 21, 2008

Spring cleaning!

We change the shavings in our bird pens regularly. It’s a big job, but sometimes the birds pitch in. Here is a video of Niles the southern ground hornbill “helping” me out.

To learn more about the gloriousness of Niles, see my post from March 13th!

Thursday, March 20, 2008

Education spotlight: Kahn

Albino Burmese Python
Python molurus bivittatus

One of the largest snakes in the world, the Burmese Python is found in the jungles of southeast Asia. They are a diurnal snake, which means that they are most active during the day. Burmese pythons are carnivorous and, like many snakes, hunt their prey by using chemical sensors in their tongues. As they grow, these snakes leave the trees to live on the ground, feeding primarily on small mammals and birds. They can stay submerged in water for as long as 30 minutes and are excellent swimmers. Once it has caught its prey (sharp teeth!), the python uses its powerful body to surround and constrict, suffocating the animal to death. Burmese pythons can grow up to 25 feet in length or more and weigh up to 200 lbs. Sadly, these beautiful snakes are a threatened species, their numbers depleted due to habitat loss, poaching, and the pet trade.

This is Kahn, our Albino Burmese Python. Albino snakes don’t generally survive in the wild because they have trouble controlling their body temperature and are more visible to predators. Kahn is 11 feet long and weighs a whopping 50 lbs. We don't know his exact age, but Burmese Pythons can live for more than 25 years.


For more information on Burmese Pythons, check out nationalgeographic.com, which was a valuable source for this post.


Wednesday, March 19, 2008

Raptor Propagation: Imprinting

Imprinting is defined as “a learning process by which a newborn or very young animal establishes a behavior pattern of recognition and attraction to another animal of its own kind or to a substitute identified as the parent” (American Heritage Dictionary).

Captive breeders generally use the term “imprint” to refer to a bird who has developed an attachment to people. Unless the bird is being hand raised for education or, in the case of pet birds like parakeets or parrots, companionship, imprinting can cause problems for the bird.

At the sanctuary, we sometimes see birds that have been taken (often illegally) from the nest as chicks and hand raised. These birds have never learned to feed themselves or interact with others of their species. As they grow older they identify with humans as mates, leading to a variety of miscommunications. As you can imagine, there is a fine line between “romance” and “attack” when a golden eagle decides to take you as its mate! Sadly, these birds are often relinquished or, worse, abandoned.

At WBS, we hand raise birds we intend to use for education programs. It is sometimes the case that a chick is at risk from a parent or sibling in the nest box and must be pulled and hand raised. Otherwise our birds are parent raised from the egg.

Here are pictures of Willard, a red-tailed hawk who was taken illegally from the nest as a chick. As a result of imprinting, Willard cannot be released in the wild. He’s a mellow guy and loved by the staff, but this is not the life he was hatched to lead.


Tuesday, March 18, 2008

World Eagle Day Revisited...

For those of you who couldn't be with us, here are some photos and a video medley of our Eagle Day celebration. Be sure to watch the end of the video when our bald eagle Lewis flies across the stage. It was a wonderful time!





Monday, March 17, 2008

Monday morning haiku...

Today we have two haiku from staff member Susan Burchardt concerning the sometimes fickle love of a Eurasian Eagle Owl named Caution:

Get off me, Caution
My shoe's not an eagle owl
But thanks for the chick
Dismissed by the owl
My shoe no longer worthy
No eagle owl love

Sunday, March 16, 2008

Raptor Propagation: Getting out of the egg is hard work!

Once the egg’s air sac is in draw down, the chick’s lungs begin to function at an increased capacity. At this point, the chorioallantois membranes begin to reduce their blood flow. Once the membranes have shut down, the chick can safely break the membrane and begin pipping the shell.

It takes 24-72 hours for the chick to go from pip to hatch. During this time, the chick begins breaking up the area around the initial pip, sometimes creating a hole in the shell (see post from March 1, 2008 for a video of this part of the hatch). At this point, if the egg is held gently to your ear, the chick can be heard clicking and chirping inside the egg.

Next, the chick turns in its shell, using the egg tooth to break a line around the circumference of the large end of the egg. This part of the hatch progresses gradually, with the chick turning, then vocalizing, then stopping to rest before it resumes.

When the chick emerges from the egg, its down is damp and matted. Its closed eyes are large and bulging. The chick also has a prominent muscle along the back of its neck known as the “hatching muscle” which disappears 1-2 days after hatch.

During hatching, the egg yolk is retracted into the chick’s abdominal cavity, where it secretes through the “yolk stalk” into the small intestine and from there to the stomach for digesting. Thus, the yolk continues to nourish the chick through the first 24 hours of its life.

For further reading, I recommend James D. Weaver’s Falcon Propagation: A Manual on Captive Breeding which was the primary source for this post.

In the next installment of “Raptor Propagation”, I’ll discuss imprinting and hand raising chicks.


Saturday, March 15, 2008

Who's on eggs? Tawny owls!

Family Strigidae, Strix aluco

Tawny owls are medium sized owls found in Europe and Asia and have red, grey, and brown color morphs. They are related to the barred owl found in the US. Tawny owls prefer to live in woods and open areas with large trees for perching. Their call is the famous "to-Wit, to-Woo."

With the loss of much of their rural habitat, tawny owls are moving into cities and suburbs. Their hunting techniques have changed with their new environment. One new technique involves landing on a branch and then slowly walking sideways along the limb until it is next to a sleeping songbird. One quick snatch, and the owl has a meal!

This is Bronte, one of our tawny owls. Her mate is named Dickens. This their first egg of the season, but they are experienced parents.




Friday, March 14, 2008

Raptor Propagation: What goes on in those eggs, anyway?

As captive breeders, we carefully monitor the progress of our eggs to insure that the embryo is developing properly and make adjustments in the care of the egg when need be. The eggs are weighed and candled on a regular basis.

By the time they hatch, avian eggs lose approximately 18% of their fresh egg weight, or the weight of the egg upon laying. Weight loss is a good measure of the health of a chick and is charted and graphed along the way.

Ideally, eggs are incubated by the parents. When this is not possible, the eggs must be fostered by another bird or incubated (see picture of incubator below) and carefully managed. To manage weight loss, we weigh the egg every three days and adjust the humidity inside the incubator to help speed or slow the weight loss. If an egg loses weight too quickly or slowly, it may lead to problems for the embryo.

Candling allows us to observe the contents of an egg without breaking the shell. Initially, we candle eggs to determine fertility as well as the extent of incubation. Depending on the egg’s pigmentation, fertility can usually be determined in 5-10 days after laying, with darkly pigmented eggs taking the longest. The eggs must be handled gently and candled for no more than 10 seconds to avoid over-heating the embryo.

An egg candler (above) is a small machine that puts out a narrow beam of light. When candling eggs, the room must be completely dark. An experienced candler makes several observations of the egg:

First, the shape and condition of the air sac is noted. A change in the air sac is one indication of possible fertility.

Next, we look for a shadow, or “half-shading,” at the top half of the egg. Half-shading is caused by a network of capillaries and veins that occur as an embryo develops. The half-shading should be reddish in color.

At 10 days, the air sac should be noticeably larger and half-shading very pronounced. At this point a small embryo or “eye spot” is visible, floating in the egg.

By 15 days, the network of blood vessels is highly visible and the embryo is moble, often responding to bright light with a swimming motion.

Towards the end of the incubation period (approximately 30-31 days) the air sac expands down one side of the egg in a process called “draw down.” Shortly after draw down, the chick breaks through the membrane with its head in the air sac and begins pipping at the shell.

In this picture, you can compare the relative sizes of a Harris Hawk egg (right) and a Bald Eagle egg (left).


For further reading, I recommend James D. Weaver’s Falcon Propagation: A Manual on Captive Breeding, which was a valuable source for this post.

Thursday, March 13, 2008

Education spotlight: Niles!

Probably the most famous of our birds (looks are everything) and a national showbiz sensation, Niles is an African Southern Ground Hornbill. He’s 4 feet long and weighs around 7 lbs.

Southern ground hornbills live south of the equator in the savannas and grasslands of Africa. They eat lizards, insects, snakes, and small mammals. This terrestrial species is the only hornbill that does not wall up the female in her nest.

Though their status in the wild is largely unknown, according to the World Association of Zoos and Aquariums, their numbers are declining from loss of habitat through degradation, encroachment and settlement, destruction of large nesting trees, poisoning, shooting, trade in exotic birds and traditional medicinal use. 50% of their original habit has been lost in the past 60 years (waza.org).

As an ambassador for his species, Niles helps to raise awareness of the plight of African birds. Niles loves to perform and can be seen in all his glory this summer at the Stone Zoo in Boston, MA.

Wednesday, March 12, 2008

World Eagle Day! World Eagle Day!

Where? The World Bird Sanctuary in Valley Park, MO.
When? Sunday March 16, 11 AM to 4 PM.
How much? Free
Who's invited? You!

Come join us this Sunday for our world eagle celebration! For a preview of coming attractions, check out this video of our bald eagle Lewis practicing for the show:

Tuesday, March 11, 2008

Raptor Propagation: The Egg

The egg is a complex and marvelously efficient self-contained universe. In this post, I’d like to share with you the basic components of eggs and how they function in protecting and nurturing the embryo.

The avian egg contains three membranes that support the life and development of the embryo:

The amnion is an inner layer of cells that surrounds the embryo and secretes the amniotic fluid in which the embryo floats. The amnion both protects the embryo and prevents it from drying out.

The chorion surrounds the embryonic structures and serves as a protective membrane.

The allantois (or allantoic sac) grows larger as the embryo develops, eventually fusing with the chorion. The chorioallantois works to permit respiration and excretion. It is important in storing the chick’s nitrogenous waste, or uric acid.

The four primary components of an avian egg (from the inside out) are:

The yolk, which feeds the chick during and after incubation. The avian yolk is between 21% - 36% lipids and 16% - 22% proteins (the rest is water), and is suspended in the center of the egg by the chalaze, which are strands of protein fibers. The yolk also contains antibodies from the mother to protect the chick from infection.

The albumen is the chick’s water supply as well as a buffer that helps protect the embryo from jostling or sudden changes in temperature.

Shell membranes (inner and outer) are attached to the shell and help protect the egg from bacterial invasion as well as preventing rapid evaporation of moisture from the egg.

Finally, the shell is the embryo’s outermost protection. Eggshells contain thousands of pores to permit gas exchange. The color of an egg shell is determined by pigments in the mother’s uterine wall.

When the egg is laid, it begins to cool and the inside contracts, forming an air sac. Observation of this air sac allows us to monitor the progress of incubation and indicates when the egg is near hatch. More on that in my next propagation post when I’ll answer the question: She laid an egg, now what?

And here is another video of a barn owl chick. He’s awfully cute at three weeks old!


Two sources were used as a reference in preparing this post:
http://www.msstate.edu/dept/poultry/avianemb.htm
http://people.eku.edu/ritchisong/avianreproduction.html

Monday, March 10, 2008

Monday Haiku: A Mammalian Moment

Though we are 99% avian, we do have a small collection of mammals (not counting staff and volunteers!) including our pair of fruit bats. Because they spend most of their days sleeping and snuggling under their tent, I rarely get to see them, but last week they came out to play. Well... ok... to eat, which is nicely tied to today’s haiku by training specialist Susan Burchardt:

We don’t want fat bats
Lowfat yogurt grows on trees
They seem to believe



Sunday, March 9, 2008

Raptor Propagation: It takes two to make the egg!

Many of the breeding pairs at WBS have come to us because of injury or confiscation, others have been captive bred themselves. When a pair successfully lays a clutch in the nest box we’ve provided, the propagation department becomes an extremely busy place to be! To give you an idea of who lays and when, here’s a short list of a typical season. Surprises can happen, but generally the birds follow a rough schedule from January to July:

January: This is when our season begins. The nests and platforms as well as our incubators are cleaned, prepared, and ready to go during the first week of January. We begin checking barn owl and eagle owl nests every Monday. When an egg is found, the date is recorded and the nest is checked on Wednesday and Friday to be better aware of the incubation dates. This process is repeated with every breeding pair throughout the season. Barn owls may begin laying in January.

February: Barn owls, Eurasian eagle owls, and augur buzzards lay.

March: Lanner falcons, tawny owls, and ferruginous hawks.

April: By April, we are in full swing! In addition to the eggs and hatchlings we already have, we begin looking for bald eagles to lay, usually around Easter.

May: May can be a busy month, with overlaps from April and June.

June: Harris hawks, abdim storks, pied crows, black vultures

July: In July, things are tapering off. We keep a close eye on our birds to protect them from excessive heat.

And as this video shows, the augur buzzards were right on schedule this year!



Stay tuned for the next installment of “Raptor Propagation” when I’ll answer the question: What exactly is an egg?

Saturday, March 8, 2008

Raptor Propagation: Why do we captive breed?

This is a common question from visitors and volunteers and I think it’s a good one.

Captive breeding is done for a number of reasons. One of our missions at the World Bird Sanctuary is to help preserve the biodiversity of bird species. When a species is threatened by encroaching development, their fragmented habitat prevents many birds from breeding and severely limits genetic diversity in a population. As habitats worldwide are destroyed, many species are becoming behaviorally trapped. Living in a small area usually leads to extinction.

By banking, or preserving, the genetic diversity of different species for future generations, we increase the possibility that they will avoid extinction and, ideally, be restored to their original habitats.

In addition, some of our birds are bred for education. Captive birds are a teaching tool for interns, staff, and scientists, as well as our visiting public. They help build an interest and investment in the continued support of species survival programs.

Some birds, like our barn owls, are raised for release. Here is a new video of our barn owl Athena and her chicks. The oldest is now 5 weeks and they are growing up too fast!



In the next few weeks, I'll be posting on the propagation process from egg to fledge. If you'd like to see them all together, click on "propagation" in the subject links on the right side of your screen.

Friday, March 7, 2008

Education spotlight: Bateleur Eagle

Family Accipitridae, Terathopius ecaudatus

The bateleur eagle (bateleur comes from the French, meaning acrobat or tumbler) is an African eagle most famous for their tail, or lack thereof. With a tail only two inches long, they are capable of amazing stunts in flight, doing complete sideways barrel rolls. They are also known as the Snake eagle because they are one of the few predators of venomous snakes. They use their extensive plumage to "puff up" when striking a snake so that even if the snake bites, it only gets a mouthful of feathers. They stand 22 to 28 inches tall and have a 5 to 6 foot wingspan.

The video below is of Shadow, our bateleur eagle. Shadow was taken illegally from his home in Africa, confiscated by U.S. Customs, and given to the sanctuary. He now works as an education bird. Here you see him doing his display. He can be a bit territorial about his perch. He displays by puffing up very large, standing tall and then dipping his head to his toes. You can hear him call as he displays.

Thursday, March 6, 2008

A crow I know...

I’d like to introduce you to Einstein! Einstein is an African pied crow, Family Corvidae, Corvus albus. He’s a very sweet bird who likes to say “hello” and make knock-knock sounds. African pied crows are about the same size as our American crows and can learn to mimic around 100 words and five phrases. In our education programs, Einstein will take recycleables (paper, plastic, and aluminum) from our audience members and place them in a recyle bin. He’s very fond of grapes.

Wednesday, March 5, 2008

Hatch alert! Augur buzzards are out of the egg...

Tyler and Arusha’s first chick hatched on Saturday. This is the chick who was pipping in the earlier video. As you can see, she or he is quite vocal and doing well. The second chick is on its way out of the egg in this video.

Notice that when Arusha comes to brood, she balls up her talons in order not to harm her chicks. She’s a very good mother! See below the video for more information on Augur Buzzards.


The Augur Buzzard (family Accipitridae, Buteo rufofuscus) is the highest flying hawk in Africa and can reach heights of more than 10,000 feet. They stand 21 inches tall and have a wingspan over four feet wide. They are larger cousins of the red tailed hawk of North America and have a brick red tail, just like the red tailed hawk. Their nickname "the jackal" comes from their loud laughing call.

Augur Buzzards are one of the more common birds of prey in Africa and are found in the East African countries of Tanzania, Zimbabwe, and central Namibia. They diet primarily on reptiles like lizards and snakes, but they also eat small mammals and carrion when need be.

Female Augur Buzzards are around 10% larger than males. Here is a picture of one of our Augur Buzzards used for education, Kee-oo. Kee-oo is a dark phase female. She hatched in 1992.

Tuesday, March 4, 2008

Who's on eggs?

As we look forward to more spring babies, one chick I can't wait to see hatch is the Lanner Falcon. In the wild, Lanner Falcons are found primarily in Africa, but their range extends into parts of Greece and Italy as well as Asia Minor. Lanners are monogamous and known for their dramatic courtship flight displays. They typically lay between 1 and 5 eggs that incubate for 32 days before hatching.

Here you see our Lanner Falcon, Laela, settling down to incubate her two eggs.

Monday, March 3, 2008

Monday morning haiku...

Mondays seem like the perfect day to offer our readers something a little different.In that spirit, we've decided to feature a new haiku every week, courtesy of our staff members. When we have accumulated enough, we'll have a haiku-off and let you, the readers, choose a favorite!

This week's haiku is a timely one (see yesterday's video) brought to you by our propagation specialist, Jennifer Bender:

A baby barn owl
who wants a fat mouse for lunch
must mind its manners.


Sunday, March 2, 2008

Banding the barn owl chicks

All birds that we breed have to be banded and reported to the U.S. Fish and Wildlife Service (USFWS) at the end of the calendar year. When the chicks are two weeks old, we put a numbered, seamless band that we get from USFWS on their leg. We put them on at two weeks because at that age they are still small enough that the band can be slipped on over the foot, but big enough that it doesn't slip off.

With our release birds, we replace the seamless band with a release band at the time of release. Our goal is to raise the barn owl population here in Missouri, where barn owls are rare.

Saturday, March 1, 2008

Hatch alert! Augur Buzzard pipping

As you can see from the video below, new augur buzzards are on the way! The augur buzzard chick has started to pip, or break, out of the egg. As Arusha switches with Tyler, you can see one of the eggs has a hole in it. She was chirping to the egg and it was chirping back.

"What is the hatch process?" you may ask. First, the chick breaks through the membrane that surrounds it into the air cell at the larger end of the egg. When that happens, you can hear the baby cheeping and the egg starts rocking and rolling. As the CO2 builds up, the chick's neck muscles start to contract and it breaks the egg shell (see hole in egg below). Breaking into the air cell is called an internal pip, while breaking through the shell is called an external pip.

The hatching takes anywhere from 24 to 72 hours. We don't generally intervene because it takes time for all of the blood vessels in the membrane to shut down. If you tear the membrane before they shut down, the resulting blood can kill the chick.

This baby will be raised by the parents in order to avoid imprinting.