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28 June 2010

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This section of field biology will introduce you to the ecology of birds and youll be expected to learn the common & scientific names of 40 species Things youll need Binoculars Field guide

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Monday (today) Course overview & introduction to birds lecture Tuesday (June 29 th ) Introduction to binoculars lecture Nests & mates lecture Growth & development lecture

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Wednesday (June 30 th ) Mist-netting demonstration at Dr. Butlers house (bring binoculars, camera) Thursday (July 1 st ) Demography and populations lecture MARK lab Species and Communities lecture

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Worth 100 pts Short answer 50 pts Multiple choice 50 pts Short answer will be to identify birds Will put together a random PowerPoint presentation with 20 of the 40 birds by sight 10 of the 20 birds by song Youll have 50 seconds per species to write down common name & scientific name Spelling (and capitalization) counts! Multiple choice will cover lecture material

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"I am but mad north-north-west: when the wind is southerly I know a hawk from a handsaw." --Hamlet, Act II, scene ii Bird identification runs the gamut from easy (adult Bald Eagle) to the extremely difficult (separating silent Empidonax flycatchers) There are ~650 bird species that breed (or have bred) in the US and Canada 470 of these species occur in Oklahoma

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For this class youll need to know common name, genus and specific epithet Genus and specific epithet is always italicized When you are writing it by hand you can either write genus & species in cursive or you can underline genus and species. Ex: Sitta canadensis or Sitta canadensis Never: Sitta canadensis or sitta candensis Common names have been standardized in the US for over a century and are considered to be proper nouns Capitalize them accordingly! E.g. Red-breasted Nuthatch, rather than red-breasted nuthatch

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Over 9,000 species have been described worldwide Birds live in all biomes, from mountains to prairies, on all oceans, and from the North to the South Pole. The Bee Hummingbird (of Cuba) is one of the smallest vertebrate endotherms at 5.5 cm long. The feather is the unique and essential feature or hallmark of birds; however, feathers were also present in some theropod dinosaurs, although these feathers were not capable of supporting flight and obviously served in other capacities such as thermoregulation or mating behavior. Image from: http://encarta.msn.com/media_631509452_761569844_- 1_1/Bee_Hummingbird.html

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The discovery of the fossil of Archaeopteryx lithographica in 1861 linked birds and reptiles.

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Thomas Henry Huxley classified birds with theropod dinosaurs. Theropods belong to the lineage of diapsid reptiles, the archosaurians, which includes crocodiles. Fossil evidence from Spain, China, etc. is accumulating that Huxleys theory is correct. Dromeosaurs, a group of theropods that includes Velociraptor, share many additional derived characters with birds, including a furcula (fused clavicles) and lunate wrist bones that permit swiveling motions used in flight.

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Feather Quill Knobs in the Dinosaur Velociraptor Turner et al. (2007) Quill knobs were located on the posterior forearm Quill knobs indicate feathers

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The hollow quill emerges from the skin follicle and continues as a shaft or rachis. The rachis bears numerous barbs. Up to several hundred barbs are arranged to form a flat, webbed surface, the vane. Each barb resembles a miniature feather; numerous parallel filaments or barbules spread laterally.

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Feather color may be due to pigments or to structural color. Pigments, or lipochromes, color red, orange and yellow feathers. Black, brown, red-brown, and gray colors are from the pigment melanin. The blue color of the Blue Jay, Indigo Bunting and Eastern Bluebird is from scattering of light by structure.

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Compared with the Archeopteryx, modern birds have light, delicate bones laced with air cavities. These are termed pneumatized bones; they are nevertheless strong. The total weight of a birds feathers may outweigh its skeleton.

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Most caudal vertebrae are fused into a pygostyle. Fused clavicles form an elastic furcula that apparently stores energy as it flexes during wing beats.

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Both the pectoralis muscle (which lowers the wing) and the supracoracoideus muscles (which raises the wing) are attached to the keeled sternum The pectoralis contracts, causing the wing to move downward Relaxation of the pectoralis causes the supracoracoideus muscle to contract

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Dark meat has more myoglobin Myoglobin is similar to hemoglobin it binds oxygen and provides it to muscles Muscles are composed of fast-twitch (white fibers with little myoglobin) and slow-twitch (dark fibers with lots of myoglobin) Fast-twitch fibers depend on anaerobic glycolysis for energy production while slow-twitch rely on aerobic TCA or Krebs Cycle for energy production Muscles used frequently (e.g. legs in turkeys) are typically dominated by slow-twitch fibers

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Omnivorous birds are euryphagous, specialists are stenophagous

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Contrary to the saying to eat like a bird meaning to eat little, birds are voracious feeders. A hummingbird eats 100% of its body weight each day, a blue tit about 30% and a chicken, 3.4%. There are few taste buds, but birds can taste to some extent Esophagous Crop Stomach (Proventriculus & Gizzard)

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The four-chambered heart is large, with strong ventricular walls. Birds share with mammals a complete separation of respiratory and systemic circulations. The heartbeat is relatively fast compared to mammals and is inversely proportional to size. A Black-capped Chickadees heart beats approximately 500 times per minute Bird red blood cells (erythrocytes) are nucleated and biconvex

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The finest branches of the bronchi are tube-like parabronchi leading to air sacs. A large portion of the air bypasses the lungs and flows directly to the air sacs on inspiration. On expiration, this oxygenated air flows through the lungs. Thus it takes two respiratory cycles for a single breath of air to pass through the system.

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A pair of large metanephric kidneys is composed of many thousands of nephrons. Each nephron has a renal corpuscle and a nephric tubule. Note that bird kidneys are less efficient than mammal kidneys Birds use the vertebrate pattern of glomerular filtration and selective resorption. Urine flows through ureters to the cloaca, where urine is concentrated into uric acid.

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The core of the cerebrum, the corpus striatum, is enlarged into the principal integrating center. The cerebellum is where muscle-position sense (proprioception), equilibrium sense and visual cues are assembled. The optic lobes bulge to each side of the midbrain and form a visual association apparatus. Sense of smell is (usually) less well developed then in mammals

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The bird eye is similar to the mammal eye, but it is relatively larger for a given body size. A pecten is a highly vascularized organ attached to the retina and it juts into the vitreous humor Many birds have two foveae or regions of detailed vision; this provides both sharp monocular and binocular vision.

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The early airspace was an unexploited habitat with flying insects for food. Flight also provided rapid escape from predators and ability to travel to better environments. There are two hypotheses on the evolution of bird flight. 1) The ground-up hypothesis is based on running birds with primitive wings to snare insects. 2) The trees-down hypothesis has birds passing through tree-climbing, leaping, parachuting, gliding, and finally powered flight. Feathers preceded flight and arose for thermoregulatory purposes.

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Over two-thirds of the total lift comes from negative pressure from the airstream flowing a longer distance over the top of the wing, the convex surface. At a point near 15 o, the angle of attack becomes too steep and stalling occurs.

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Use of visual landmarks (short-distance) Solar compass (long-distance) Stellar compass (long-distance) Olfaction (short-distance) Response to geomagnetism (long-distance)

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Garden Warbler image from http://news.nationalgeog raphic.com/news/bigphot os/61412945.html

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There are many advantages for flocking together: mutual protection from enemies, greater ease in finding mates, less opportunity for an individual straying during migration and mass huddling for protection against low night temperatures during migration.

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Males of most species lack a penis; mating involves bringing cloacal surfaces in contact. In most birds, the left ovary and oviduct develop and the right ovary and oviduct degenerate. The expanded end of the oviduct, the infundibulum, receives the discharged eggs. Special glands add albumin or egg white to the egg as it passes down the oviduct. Farther down the oviduct, the shell membrane, shell, and shell pigments are also secreted.

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Over 90% of bird species are monogamous; they only mate with one partner each breeding season. Monogamy: In a few species, such as swans and geese, partners are chosen for life. A smaller number are polygamous; individuals mate with two or more partners each breeding season. Examples include polygyny (one male, many females) and polyandry

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