MadSci Network: Zoology

Re: Where do I see baby pelicans and where do birds go during a storm?

Date: Mon Oct 9 09:05:02 2000
Posted By: June M. Wingert , RM(NRM),Associate Scientist
Area of science: Zoology
ID: 969649209.Zo

Below you will find the answer to both of your questions concerning baby 
pelicans and what happens to birds when it storms.  The question of where 
birds go when it storms was previously answered on the Mad Sci Network.  I 
have included the message number so you can look up the answer for a 
different perspective.

                                                 Ever Seen a Baby Pelican?

As one ponders these extraordinary birds which are a regular feature of 
our waterways, it is hard to imagine what a baby pelican looks like. Where 
do they nest?
Why do we never see them paddling behind the adults as we so often see 
with other waterbirds?

Pelicans nest in colonies, usually on isolated islands away from ground 
predators. The breeding pair share the tasks of building the nest, 
incubation and feeding the
young. The nest, a crude platform of sticks lined with grass or seaweed, 
usually contains 2-4 eggs. Pelicans from the Shoalhaven may travel great 
distance to
undisturbed nesting sites and it is only when the young are strong enough 
to fly that they are able to return to the area. 

                                                      The Pelican 

Anyone who has observed this magnificent bird in close-formation flight, 
just brushing the waves as it scavenges the last bit of lift from the 
wind, must conclude that
nature far exceeds man in understanding aeronautical design. The bird is 
huge, sometimes with a wing expanse of nearly 10 feet, and the head, 
outstretched and the
neck neatly drawn up, belies the presence of the pouch which can if fully 
extended and wide stretched, encompass a fish weighing over a pound. And 
yet in flight, all
this is obscured as it gracefully glides alone, in pairs or small groups 
of birds that are perhaps related or perhaps not. And if this is not 
enough, a gull may be
accompanying the pelican(s). At once the gull is an ever-present 
companion, there to rob the pelican of its newly captured fish or if 
returning to the nesting area to
prey on eggs and the defenseless young. 

It has been said that the pelican uses its large, thin, skinny bag that 
hangs beneath its bill to dip-net small fish. In observing white pelicans 
in the race waters below the
dam at Lewis and Clark lake on the Missouri River, it does appear that 
they are active in the water perhaps catching confused or injured fish 
that have passed
through the turbines. They swim in perfect formation, not unlike their 
patterns in flight. A lead pelican dips its head beneath the water and in 
synchrony, the others
follow him in searching the clear cold water for today's meal. How 
successful they are is impossible to judge. With head raised, water 
drained from the pouch, the
point pelican returns to its vigilant role awaiting the next fish. As 
pointed out in the book, Birds in America, while it was once thought the 
pelican could convey live
fish via the extended pouch, this was questioned by Audubon who pointed 
out that it is doubtful that the pelican could fly at all with his 
burdensome pouch so out of

The brown pelican is perhaps the most familiar of the some ten species 
that exist. This is the common pelican of Florida, the Gulf and Atlantic 
coast. This is the bird
that we see crashing down from a height of 10 to 50 feet into the waves. 
He is often successful in capturing his prey, as upon emerging from the 
deep, he is seen to
pause sometimes for up to a minute, then raise his head, straightening his 
neck and with a quick motion, rearranging his catch so that it can be 
easily swallowed.
Anyone that has tried to spot fish in the water, regardless of angle, 
distance or lighting, must be awed by the vision of this strange creature. 
How can it see the fish,
determine the depth, direction in which it is swimming, size (for a fish 
too large is of no value), and perhaps variety; and then plunge headlong 
with wings folded to
increase speed and reduce impact upon entering the water; catch the fish; 
and bob to the surface. Amazing! 

But on land (a convenient post, tree limb or sign will do) the pelican 
reveals itself in all its ugliness. It is ungainly, if not uncouth. As it 
preens itself, the beak carefully
arranges feathers wet by a recent dunking. But no matter how it tries, it 
cannot obscure the fact that it is truly ugly. The thin, large, skinny bag 
that hangs from the
lower part of the bill has been said to be quite considerable in its 
capacity, and it dangles like a dowagers wrinkled neck. It does not add 
any to the attractiveness of
this bird. And if this is not enough, just like our own species, as it 
passes through puberty; in the case of the pelican at the beginning of 
breeding season, the pelican
develops an enormous zit (called a excrescence by birders) on its upper 
mandible (nose if you prefer). 

William Finley wrote in Birds of America; "The first time I ever saw a 
motley crowd of half-grown pelicans, I thought Nature had surely done her 
best to make
something ugly and ridiculous. It was a warm day and the birds stood 
around with their mouths open, panting like a lot of dogs after a chase, 
their pouches shaking at
every breath. When I went near, the youngsters went tottering off on their 
big webbed feet with wings dragging on this side and that, like poorly 
handled crutches.
The youngsters huddled together by hundreds in a small place. Those on the 
outside pushed and climbed to get near the center. till it looked worse 
than any football
scrimmage I ever saw." If one looks at the immature pelican, one is 
reminded of a plucked chicken, ready for the boiling pot. But, the large 
head, extended neck and
duck like feet remind you that this is not an ordinary bird." 

Finley further wrote; "One might wonder how such a huge-billed bird as a 
Pelican could feed helpless chicks just out of the egg. It was done with 
apparent ease. The
old bird regurgitated a fishy soup into the front end of his pouch (wonder 
how Finley identified the bird as male?) and the baby Pelican pitched 
right in and helped
himself out of this family dish. 

As the young bird grew older and larger, at each meal he kept reaching 
farther into the big pouch of his parent until finally, when he was half-
grown, it was a most
remarkable sight. The mother opened her mouth and the whole head and neck 
of her nestling disappeared down the capacious maw, while he hunted for 
his dinner in
the internal regions." 

The fishing habits of the white pelican and the familiar brown pelican of 
Florida&rsquos waters are distinctly different. So the following is a 
research proposal that I
hope will find interest to birders, as it will help distinguish whether 
the individual bird is pressed to accept the practices of its nest mates 
or whether it is inborn,
imprinted in the pelican&rsquos DNA and immutable. 

Imagine if you will. Eggs of the brown pelican are placed in a nest having 
white pelican eggs and the nesting bird is a white pelican. Upon hatching, 
will the mother
bird accept this strangely coloured transplant or will it be ignored. Once 
having reached maturity will the brown pelican use the same fishing 
techniques of the white
pelican or will it revert to the practice of a soaring flight, plummeting 
dive and capture familiar with its genetic parents. 

Likewise, will a white pelican egg when hatched in the presence of brown 
pelicans be accepted by its mothering hen or will it be refused food. Will 
it when mature
revert to the practice of swimming and catching fish by a quick duck of 
the head into the water. 

This proposal of observing the habits of the pelicans will be much more 
informative than those where a migratory bird egg is nested with a 
companion species, as
example the whooping crane with the sandhill cranes. 

  Joe Wortham&rsquos Home Page , About Joe Wortham 

  January 30, 1999

Wildlife and Storms Release 13 September 1996 

Debra Becker 703-648-4461 

NBS Scientists Find Wildlife Impacts During Severe Storms, But Nature 

What happens when a hurricane threatens? Homeowners and vacationers in the 
path of the storm may be able to protect their homes and travel to safety, 
but some
wildlife may not be so fortunate. Scientists at the National Biological 
Service have found over the course of many years of research that, though 
there may be some
structural changes in the habitat and populations may suffer drastic 
losses, most plant and animal populations living in storm zones are able 
to survive and recover in
time from the severe weather. 

Immobile species such as mussels and oysters may be locally wiped out in 
the impact zone. Some of these species can be transported with the debris 
of the
hurricane to distant locations along the coast and inland, often to 
habitats where survival may be difficult if not impossible. Upland 
terrestrial habitats can be flooded
or totally inundated, washing away or drowning their resident fauna, 
especially small mammals such as rabbits and mice. Nesting rookeries, 
including the eggs and
young, of colonial water birds (herons, seagulls, pelicans) can be 
completely destroyed. 

NBS scientists and their collaborators found that the Louisiana fishery 
and aquaculture industry suffered enormous losses as a result of Hurricane 
Andrew in 1992.
An estimated 184 million fish were killed in south Louisiana's Atchafalaya 
Basin alone. Andrew's winds caused widespread defoliation (leaf removal) 
of trees and
shrubs, resulting in a large influx of organic material (leaves) into the 
wetlands in a short period. This rotting material caused extremely low 
levels of oxygen in the
water, suffocating the fish. 

At the same time, 25 percent of Louisiana's public oyster seed grounds 
were virtually wiped out by Hurricane Andrew. These and other bottom-
dwelling organisms
-- which provide an important food source for wading birds on Louisiana's 
Barrier Islands -- suffered mass mortalities during the passage of 
Hurricane Andrew. 

Hurricane Hugo wreaked similar devastation on the Puerto Rican parrot 
population. Approximately half of this critically endangered population of 
less than 50 birds
was lost. In some cases the birds were killed as a result of the storm, 
while in others the changes in the habitat as a result of the storm made 
the birds more
vulnerable to predators. Scientists believe that Puerto Rican parrots that 
survived possibly roosted in the cavities of large, strong, hurricane-
resistant trees, such as
the tabonuco tree of the Caribbean National Forest. 

One NBS scientist observed songbirds on the ground and under cover during 
Hurricane Hugo, sitting tight until the storm passed. Others may have been 
blown out
to sea and perished. Oceanic birds have appeared in strange places after 
storms, having been wind-carried miles inland. The same is true for inland 
birds blown out
to sea. These birds would perish unnoticed in the deep oceans. Some of the 
inland birds might find temporary refuge and rest on ships, but without 
food it is doubtful
these birds would survive more than 24 to 48 hours. 

Manatees, large marine mammals, are well adapted to the aquatic 
environment. Because they inhabit nearshore and inland waters, they can 
usually locate sheltered
areas during stormy weather. The only known case of a manatee experiencing 
difficulty during a storm occurred when Hurricane Andrew swept across south
Florida. This huge storm caused high winds and tides along the shoreline 
of Biscayne Bay. After Andrew passed, a manatee was discovered in a 
football-field sized
pond on a golf course in South Miami, about a half-mile from the bay. This 
animal was rescued by NBS scientists, who determined that she was in good 
health and
then released her back into Biscayne Bay. 

Stream organisms are usually well adapted to all but the most severe 
floods. Freshwater mussels will remain burrowed into bottom sediments and 
are usually in
larger, lower gradient streams where rocks and other sediments are not 
picked up and moved during periodic floods. At these times fish are known 
to seek shelter in
calm waters immediately behind large rocks or other obstructions in the 
stream. Even when whole generations of stream insects are washed away in a 
flood, there
are usually survivors that persist to recolonize and repopulate the stream 
by the next generation. 

NBS scientists at the Florida Caribbean Science Center in Gainesville, 
Florida found that the effects of Hurricane Opal (October 1995) on the 
Okaloosa darter (a small fish) were positive. Scientists have been 
involved in monitoring the population of the Okaloosa darter in the six 
stream systems it inhabits in
northwest Florida for the last eight years. They have 12 permanent study 
sites that they visit twice annually. Nearly all of these study sites were 
subjected to the
extreme winds and flood conditions of the category 3 hurricane. Streams 
were criss-crossed with fallen trees every 10 meters or so. This increased 
number of fallen
trees changed the typical stream current patterns that had been previously 
observed. It seems that the amount of area with cover increased around the 
downed logs.
From other isolated flood situations that were examined, it appeared that 
as flows increased, the size and number of eddies increased. These eddies 
provided the
Okaloosa darters with refuge from severe weather conditions and the fish 
were found in slightly greater numbers after the hurricane than before. 

Occasionally a severe "1000 year flood" will occur that drastically alters 
the stream habitat and wipes out its biota. Such an event occurred in the 
National Park June 25-27, 1995. More than 14.5 inches of rain were 
measured during a 48-hour period, with larger though unmeasured amounts of 
estimated in isolated drainages in the park. Stream habitats in Virginia's 
Staunton River were totally obliterated by the floods -- mature trees were 
uprooted and
washed downstream with large boulders during this flood. All of the 
streams' fish and insects were destroyed, and the recovery time of the 
system is estimated in
decades or longer as streamside vegetation and soils reestablish. Such 
washout events are known to occur every few dec Service of the U.S. 
Department of the
Interior is dedicated to providing fuller documentation and understanding 
of the dynamic living resources of the nation. The agency is slated to 
become the Biological
Resources Division of the U.S. Geological Survey on October 1, 1996.

The following is the ID for the question of birds and storms.

Re: This may seem silly , but, How do birds survive storms.

Date: Fri Oct 23 14:20:20 1998
Posted By: Dave Williams, Science Department Chair, Valencia Community 
Area of science: Zoology
ID: 906855550.Zo 

Thanks for taking the time to send in a question to the Mad Sci Network

June Wingert
Associate Scientist
Lexicon Genetics
The Woodlands,  Texas

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