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Notable Birds of the Southwest

General aspects about birds•  There are about 10,000 species of birds in the

world.•  All birds have feathers (and they are the only

organisms who have them).•  Birds have wings, but other animals have them too

(bats, insects).•  Despite all birds having wings and feathers, some

birds run more often than fly, and some birds never fly.

Other traits (characteristic but not unique to birds)

•  Bipedal•  Have a beak•  Lay eggs•  Endothermic

Platypus

Birds as flying machines•  They have hollow

and plastic bones (5% of total weight; they often weigh less than their feathers).

•  Endothermic and have high metabolic rates.

•  Feathers: necessary to conserve heat.

98.6 ºF 110 ºF

The speed of any chemical reaction doubles with each rise in temperature of 18 ºF.

Internalconnections

Digits (fingers) are fused together

Birds as flying machines

•  Babies don't grow and develop inside the mothers' bodies. They develop in eggs outside their mothers' bodies.

•  Birds don't have bladders. A bird urinates as soon as it has to, getting rid of the useless weight. (That's why you can't housebreak even the smartest pet bird.)

All birds develop from eggs.

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Birds as flying machines

•  Energy-rich diet (seeds, fruits nectar, worms, insects, fish, rodents).

•  Fast and effective digestive system.

Cedar waxwings: 16minAt least an hour

1Kg gain: 3Kg fish eaten1kg gain: 10Kg

Birds as flying machines•  Strong muscles and a highly

efficient respiratory system. •  Big heart.•  Highly developed nervous

systems. Large brain to body mass ratio.

Lungs: 20% of body volume Lungs: 5%

keeled sternum

Are birds perfectly designed for flight?

Not really. But they are well adapted.

Natural selection is opportunistic and itworks with what there is available.

General aspects about birds•  Birds sing (calls and songs).•  Calls are simple and brief to coordinate

behavior of other members of species.•  Songs are more complex than calls.a)  To proclaim the sex of an individual.b)  To induce another individual to reveal its

sex.c)  To indicate vigor and dominance.d)  To defend a territorye)  To strengthen the pair bondf)  As a password for species identification.g)  To educate offspringh)  To announce emotional state.i)  To perfect song through practice

Birds songs (perching birds)•  The same genes that

are involved in learning how to sing and how to speak in humans.

•  These genes occupy a large part of the bird’s genome.

•  Baby birds “babble” in the same ways baby humans do.

General aspects about birds

•  Birds construct nests.•  Mostly to take care of the young.

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Precocial Birds:Chicks hatch already covered in down with eyes open.

Nest on the ground, barely scraping out a nest.

Eggs usually have a larger yolk.

Chicks usually do not remain in the nest.

Can regulate their own temperatures

Altricial Birds: Babies hatch naked, blind

and helpless, in need of a nest in a protected place where they can finish development.Usually make constructed nests in elevated, often concealed places.

Precocial birds�

Altricial birds� General aspects about birds•  Birds migrate.•  Regular movement between their breeding and wintering

areas.•  Migration is seasonal, predictable, and repeated each year.•  They migrate to the tropics in the winter because

conditions are to harsh to support them (no food, too cold).•  They fly north in the Spring to breed, to get abundant food

supplies, to avoid predators and parasites found in the tropics, and to take advantage of longer days.

In groups

solitary

The whole population

BIRD COLOR PLUMAGE

-  SPECIES RECOGNITION-  SEXUAL SELECTION: a mode of natural selection in which

some individuals out-reproduce others of a population because they are better at securing mates.

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How to maximize reproductive success

•  by making themselves attractive to the opposite sex: female choice

•  by intimidating, deterring or defeating same-sex rivals: male-male competition

Female choice•  Males benefit by frequently mating•  Females have much more reason to be

"picky”. They have a limited number of offspring and need a way to choose males that are most likely to produce high-quality offspring.

Female choice•  Symmetry, color, size of plumage,

avoidance of predators can be symptoms of disease, quality of genes.

•  Female mating preferences are recognized as being responsible for the rapid and divergent evolution of male secondary sexual traits.

Long-tailed widowbird

Female

Male

Origins and evolution

Birds are reptiles: a) many similarities in their

skeletons. b) birds have scales on their

legs very similar to reptilian scales.

But there has been much controversy over which specific reptiles birds evolved from.

Origins and evolution

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Non-avian dinosaurs are extinctTherapods

Archaeopteryx

•  Possible link between birds and reptiles.

•  Lived the Jurassic period.

•  Feathers•  Claws on forelimbs•  Wings•  Hollow bones

Feathered Dinosaurs

Caudipteryx Protarchaeopteryx robusta

Many dinosaurs had colored feathers, like modern birds

Sinosauropteryx may have had orange feathers and a striped tail.

Sinosauropteryx, a small Theropod species. Samples were taken from the base of the tail.

pigment-storing organelles

Why feathers?

•  Insulation.•  Warmth for brooding eggs .•  Sexual display•  Camouflage •  Combination of these

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Dinosauria is not extinct!

Many traits considered adaptations for flightin birds were alreadypresent in dinosaurs. Thus, some dinosaurshad pre-adaptationsfor flight.

Nature(2015)

Phylogeny of birds

Flight origins: WAIR

•  Wings evolved first to aid young (and small adults) in Wing-Assisted Incline Running : using their wings to generate traction to help them run up sides of trees, cliffs, etc. Later modifications allowed true flight.

http://dbs.umt.edu/flightlab/videos.htm

Owls•  Extraordinary hunters using both

vision and hearing:•  Highly developed hearing:

asymmetrical ears, medulla, facial disc.

•  Big eyes, night vision•  Nocturnal.•  Flight is noiseless•  Sexually dimorphic.•  Eat a large array of invertebrates

and vertebrates.•  A male and a female maintain a

territory and take care of the chicks

Western Screech OwlBarn Owl Ferruginous Pygmy Owl

Great Horned OwlElf Owl

Burrowing Owl

Elf Owl

•  The smallest owl in the American West.

•  Territorial.•  Depends on the nest holes

that Gilded flickers and Gila woodpeckers excavate on Columnar cacti.

•  It eats mostly insects and other small arthropods.

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Great Horned Owl•  The “tiger” of the owls.•  Diet: Almost any living prey,

such as mammals from mice to, birds (including other owls), reptiles, and fish. They are among the few predators of skunks, whose scent often permeates the owl's plumage.

•  Long-lived (avg 13 years)

•  A rodent specialist: mice, packrats•  Short lived: 1-2 years.•  Can breed several times a year

BARN OWL

Burrowing Owl•  They live in underground

burrows•  Despite their name they do

not dig! Use nests of prairie dogs and other mammals.

•  Eats lots of insects, as well as ground squirrels, mice, small birds, lizards and dead animals.

•  The male stands guard outside his burrow for weeks, protecting his young

Looks like a smaller great horned owlCaptures a wide range of prey species: insects (including grasshoppers beetles, larval moths & butterflies), small birds, kangaroo rats, wood rats, pocket mice, bats, grasshopper mice, frogs, and scorpions.Nests in cavities of saguaros and other trees

Western Screech Owl

Ferruginous Pygmy Owl•  A little bigger than the Elf

Owl.•  In the endangered list of

species until 2006.•  There were only 28 birds in

2006.•  Even when virtually

extirpated from Arizona, it was delisted due to pressures from developers

Water birds - Ducks

Frequent ponds, marshes, and lakes.Feed on seeds, grains, aquatic plants, insects.

Mallard

Black –bellied whistling duck

Noethern pintail

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Water Birds - Great Blue Heron•  The largest heron in

North America.•  Found in a variety of

riparian habitats (desert rivers, ponds).

•  Breed in colonies.•  Male chooses the nest

site and display to attract females.

Hawks •  Diurnal raptors with

extraordinary vision•  Eat mammals,

birds, fish, reptiles, amphibians, and invertebrates that capture with talons.

•  Territorial; most species monogamous, often for life

Cooper’s Hawk

•  Long-tailed raptors with rounded wings (to maneuver in dense vegetation).

•  They control the populations of small birds (their favorite prey item)

Harris’s Hawk•  Social birds.•  They hunt cooperatively

(for just about any small bird, mammal or lizard).

•  They capture pray without physical aggression because of pecking order.

•  An adult “alpha” female usually dominates the group, supported by a subordinate male, and often a second male.

•  Dominant female pairs with both mates plus another nest attendant.

•  The extra males assist harmoniously in building the nest, guarding the eggs, feeding the female and young.

•  DNA studies show that young have different fathers.

Red-tailed Hawk•  The most common hawk in

the US.•  Adults have a rusty red tail.•  They vary in body color. •  The ones in the SW do not

migrate.•  They mainly eat small

mammals, birds and reptiles

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New world vultures

•  Turkey vulture and Black Vulture.

•  The sanitation department of the natural world.

•  Live on carrion.•  Their digestive tract can kill

any virus or bacteria in its meals.

•  Featherless head.•  Turkey vulture detects food by

smell

Turkey Vulture

Black Vulture

California Condor

•  Ten feet wingspan (the largest bird in North America).

•  Evolved to feed on the carcasses of large mammals such as mammoths and camels.

•  Reach maturity at 6 years old. Females lay an egg every other February.

•  By 1983 only 22 birds left.

•  All surviving California condors were captured and served for parental stock for captive breeding program (double clutch).

•  The most dramatic endangered species recovery effort in wildlife conservation history (at a cost of over $35 million). By March of 2008 population numbers were over 300 (155 in the wild).

•  All condors alive today descend from 14 individuals.

Raptors have difficult lives

Cactus Wren•  Not shy and loud•  Builds many nests in chollas

and saguaros.•  Territorial, monogamous,

and does not migrate.•  Insectivore. Depends on rain,

annual plants and Banded-wing grasshoppers.

Verdin

•  Tiny and plain.•  One of the most

characteristic birds of the desert.

•  Feed on nectar and insects.

•  Build different kinds of nests (winter, summer and raising young)

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Greater Roadrunner

•  Pairs sometimes hunt cooperatively.

•  Eats mostly lizards and snakes

•  Can outrun lizards•  They hammer pray

against rocks until death.

Doves

•  Feed on seeds, nectar and fruits•  Important pollinators and fruit dispersers of saguaro

woodpeckersGila Woodpecker Gilded Flicker

Feed on insects living in the bark of trees but also fruitHave strong head muscles and thick skulls to block concussions

•  They excavate saguaros for nest sites which, when abandoned serve as nests for other birds.

•  They love to hammer out metal pipes and other echoing objects.

•  Have strong head and neck muscles to absorb the shock as they drove their bills into the trees.

•  Because Gilded flickers need bigger cavities, they hurt the saguaros and may even kill them.

Phainopepla •  Silky-flycatcher •  Has a shiny black male with

a crest, and red eyes. •  They nest in early spring with

males doing much of the nest building and child care.

•  It has coevolved with the parasitic plant, desert mistletoe.

• Mistletoe berries are its main winter food.

• Mistletoe is a hemiparasite often on mesquite.

• Its seeds are very sticky and are dispersed to other host plants when birds wipe their bills on branches or deposit droppings.

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Gambel’s Quail•  The most arid-adapted quail.•  Does not migrate.•  Rarely fly and when they do

flight is short.•  They eat insects or succulent

fruits of cacti to get water. They also eat seeds and plants.

•  Monogamous. •  Chicks are precocial, fully

covered with down after hatching and leave nest soon.

•  Congregate in groups.

Hummingbirds

Hummingbirds

• Over 300 species, all American.

• Family includes the world’s smallest birds• More brilliant iridescent colors• Fastest wingbeats (up to 80 beats per second)• Ability to fly up, down, sideways, upside down and backwards!

Anatomical and physiological Hummingbird facts

•  They have very high metabolism (t requires lots of energy to be a hummingbird).

•  They have the most rapid heart rate for a bird: up to 500 beats/min. at rest and 1260 beats/min. flying.

•  They have hearts larger in proportion to body size than other warm-blooded animals.

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•  High body temperature – 105-110F

•  Being a hummingbird is like driving a car with a one-gallon gas tank: constant need to refuel.

Anatomical and physiological Hummingbird facts

•  They may consume 70 % of their body weight in solid food per day and up to 8 times their body weight in water.

•  They can become torpid at night.

•  Torpor -Temporary hibernation- They can “power down” on cold nights to save energy and water.

•  Let body heat drop to ambient.•  Dramatic drop in heart beat.•  May forgo breathing for minutes at

a time.

Plumage: Bright iridescent colors

Plumage: Bright iridescent colors

•  The result of a combination of pigmentation and light refraction.

•  Melanin occurs in platelets (small flattened particles with air bubbles).

Platelets split light into its component colors and some are refracted back to the viewer.

•  The thickness of the platelets and the size of the enclosed air bubbles determines the color.

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Territories:•  Very territorial and aggressive.•  Both sexes defend feeding territories.•  Males defend courtship territories.•  Females defend nesting territories.•  Songs, chases, posturing.

•  Most live in tropics.•  12 or so in southern Arizona.•  Costa’s – true desert bird.•  Found out in the desert.•  Purple forehead and throat with long “mustache”.

Black-chinned and Broad-billed hummingbirds

•  nest in streamside trees in summer.•  Broad-billed – Solid blue green with a

red bill•  Black-chinned – Dark head with white

breast and purple collar.

•  Anna’s hummingbird•  Common in the Coast Ranges of California, but spreading

east to Arizona and north to British Columbia since the 1960’s.

•  Range increase due to bird feeders and flowers in suburban gardens.

•  “Flame-throated” - Crimson rose forehead and throat.