81. Vocal Copying Article describing how birds learn their songs from adult tutors and may incorporate sounds from other species into their repertoire. http://www.stanford.edu/group/stanfordbirds/text/essays/Vocal_Copying.html

Vocal Copying M any species of songbirds learn the specific song elements of their repertoires from one or more adult tutors, most often from the male parent. Such learning, for at least some species, is not confined to the period prior to sexual maturity. For example, territorial male Swamp Sparrows listen to songs from adjacent territorial males and incorporate those songs into their own repertoire. Generally, this type of vocal copying, where the individual copied (the model) is a member of the same species, is referred to as "vocal imitation" and serves as the basic mechanism underlying the evolution of dialect systems variation in songs among local populations. SEE: Vocal Dialects Vocal Functions Territoriality Sexual Selection

82. Polygyny Most birds are monogamous, but in some species the occurrence of polygyny, where one male mates with more than one female, is related to high-quality territories with an abundance of resources. http://www.stanford.edu/group/stanfordbirds/text/essays/Polygyny.html

Polygyny P Often that is precisely what is found. For example, female Marsh Wrens near Seattle, Washington, sometimes mate with already-mated males, even when bachelor males are available. The number of females mated to each male is related to the amount of emergent vegetation in the males' territories, which, in turn, is presumably an indicator of the availability of insect food. Studies of Red-winged and Yellow-headed Blackbirds, Dickcissels, Indigo Buntings, and Lark Buntings also show clear relationships between various aspects of territory quality and the likelihood that a male holding a given territory will have more than one mate. Polygyny is not always associated with territoriality. Certain seed-eating savanna species of African weavers (relatives of House Sparrows) have superabundant resources and the males are not territorial, presumably because defending an area does not increase their access to food. The females apparently do not need help from males to raise the young, and the weavers nest in colonies, minimizing the need for a partner in nest defense. The female is thus free to choose any male to father her offspring, regardless of his other attachments. Here, as in situations where males are territorial, polygyny is related to the availability of resources in this case their superabundance rather than their uneven distribution.

83. Parental Care The young of passerines when first hatched are naked, blind, and helpless and require much care which involves feeding, training and protection from predators. http://www.stanford.edu/group/stanfordbirds/text/essays/Parental_Care.html

Parental Care T he young of most egg-laying reptiles hatch long after the parents have abandoned the eggs; a few lizards and snakes guard them, and pythons incubate their eggs for a while. The young of those female snakes that carry their eggs inside the body until they hatch also receive no parental care. Among reptiles only crocodiles and their relatives tend both eggs and hatchlings. In contrast, nearly all birds provide extended care for their offspring. The exceptions are brood parasites, which foist their responsibility onto other species, and some megapodes, turkey-like birds of the southwest Pacific. Most megapodes scratch together mounds (sometimes astonishingly large) of vegetation or sand and lay their eggs inside. The heat for incubation is provided by decay of the vegetation, the sun, or (occasionally) volcanic activity. Some megapodes tend the mound, opening and closing it to regulate the incubation temperature; others desert the mound. A few megapodes do not build mounds, but simply lay their eggs in warm spots on sand or between rocks and cover them with leaves. Patterns of care in precocial birds (those with young ready to leave the nest almost immediately after hatching) vary a great deal. The major parental duties for most are to keep the young safe from predators and to watch over them as they feed. In many, however, the adults also help instruct the chicks in what's good to eat, how to find it, and how to handle it. Oystercatchers first present food to their young and then train them to find food for themselves. The latter is a long process; oystercatchers specialize in opening mussels and other bivalve mollusks, a difficult task that can be accomplished in less than a minute by an experienced individual, but one that requires many months to learn.

84. Creches Article describing how some birds adopt the strategy of grouping their young, leaving them with a guardian while both parents go off to forage. http://www.stanford.edu/group/stanfordbirds/text/essays/Creches.html

Creches T he fledglings of some bird species such as Greater Flamingos, Royal and Sandwich Terns, eiders, ostriches, and a number of penguins separate from their parents and form a group, or "creche." Whether parents continue to feed their own chicks, or the chicks feed themselves, supervision of the creche (when it occurs) is usually delegated to a small number of guardians. The guardians, of course, are related to only a small number of the young in the group. It is curious that "altruistic" guarding of unrelated young, presumably a dangerous, tiring responsibility, has evolved. Upon closer scrutiny, however, the behavior is not as altruistic as it appears. Chick-creching generally occurs among birds that breed in large, loose colonies and whose eggs all hatch at about the same time. The day-care system permits a fledgling to lose itself in a crowd and reduce its risk of predation (dilution principle). In the case of young remaining dependent on their parents for food, creching frees the adults to spend more time foraging. Evolutionary theory suggests that creching is likely to develop when the young reared in a gang have a better chance of surviving than those reared alone, so that the birds practicing creche formation contribute more of their genes to the next generation than those that do not form creches.

85. Bird Milk Article describing how the young of some birds are fed on special secretions from their parents. http://www.stanford.edu/group/stanfordbirds/text/essays/Bird_Milk.html

Bird Milk L ike mammals, the young of some birds are fed on special secretions from a parent. Unlike mammals, however, both sexes produce it. The best known of these secretions is the "crop milk" that pigeons feed to squabs. The milk is produced by a sloughing of fluid-filled cells from the lining of the crop, a thin-walled, sac-like food-storage chamber that projects outward from the bottom of the esophagus. Crops are presumably a device for permitting birds to gather and store food rapidly, minimizing the time that they are exposed to predators. Crops tend to be especially well developed in pigeons and game birds. Crop milk is extremely nutritious. In one study, domestic chicks given feed containing pigeon crop milk were 16 percent heavier at the end of the experiment than chicks that did not receive the supplement. The pigeon milk, which contains more protein and fat than does cow or human milk, is the exclusive food of the nestlings for several days after hatching, and both adults feed it to the squabs for more than two weeks. The young pigeons are not fed insects as are the chicks of many seed-eating birds; instead, the crop milk provides the critical ration of protein. The milk of Greater Flamingos contains much more fat and much less protein than does pigeon milk, and its production is not localized in a crop, but involves glands lining the entire upper digestive tract. Interestingly, the milk contains an abundance of red and white blood cells, which can be seen under the microscope migrating like amoebas through the surface of the glands. Young flamingos feed exclusively on this milk for about two months, while the special filter-feeding apparatus that they will later employ for foraging develops.

86. Urban Birds Article discussing how birds have adapted to urban foraging amid the artificial concrete and steel ecosystems of cities. http://www.stanford.edu/group/stanfordbirds/text/essays/Urban_Birds.html

Urban Birds R eferring to an inner-city bird perched on a neglected dumpster as an avian cockroach or feathered rat may well raise appreciative nods. In fact, the ability of vast numbers of birds to make their homes in cities regularly calls upon the ingenuity of people to establish bird-free zones. This situation is not restricted to North America. In Moscow, for example, to keep Hooded Crows from sliding down renowned and easily scratched gold-leaf on onion domes, recordings of falcons and Northern Goshawks (the crow's major predators) were played and trained falcons released. Animal rights activists periodically disapprove of such niche-emptying efforts, but when birds are in conflict with people, it is the avian populations that are reduced and the human populations appeased. But not all city dwellers consider urban birds as candidates for extermination. More and more people, in addition to those who enjoy feeding pigeons and sparrows in parks, are viewing their avian neighbors with interest. For birders who cannot often venture into a natural setting there is a wealth of avian activity to watch right in the city. Some urban birds become uncharacteristically tame and relatively simple to observe. It is easier, for example, to witness the maintenance of dominance hierarchies in slow-gaited city pigeons (Rock Doves) than in their fast-flying country cousins. Similarly, city crows, park ducks, outdoor restaurant House Sparrows, and parking lot Brewer's Blackbirds are more approachable than their rural brethren.

87. Moulting Talk given by Avian Vet A. K. Jones to a conference of the Association of Avian Veterinarians in August 1998. http://www.parrotpassionsuk.com/Advice/Moulting.htm

The Normal Moulting Process in Birds (Originally presented to the Association of Avian Veterinarians Annual Conference August 1998) The long contour feathers of the wing are collectively known as remiges, and those of the tail are retrices. The whole of the feathers on the bird constitute its plumage. The second group includes down feathers, or plumules, which are softer and shorter than contour feathers. They do not have interlocking barbules, hence the barbs form a looser structure giving a softer feel and allowing air pockets between them. The trapped air provides an insulating layer in the plumage, and these down feathers are found under the contour feathers of the body. They are present exclusively in the chicks of many species before contour feathers develop. Those chicks which hatch from the egg already possessing downy plumage are known as ptilopaedic; those which hatch with no feathers but grow their down later are psilopaedic.4 Modified plumes known as powder down feathers are found on the flanks of many species, notably African grey parrots, Cockatiels, and white Cockatoos. These are small plumes with brush-like tips that break up into a fine white powder, which the bird then disperses through its plumage as a conditioner. They are generally the first feathers to be damaged and disappear if a bird is infected with virus diseases such as Psittacine Beak and Feather Disease (PBFD). The third group includes filoplumes, possessing long shafts with a small tuft of barbules at the tip.

88. EcoBirds Behaviour Provides a series of bird articles covering nesting, song, migration and the curious habit of anting. http://birds.ecoport.org/Behaviour/EBbehaviour.htm

EcoBirds home birding participate site map ... identification behaviour health resources Nesting Flight Song Migration Anting Courting Rituals Behaviour There are many types of behaviour in birds that range in duration, type, purpose and frequency. In fact, practised bird watchers are aware that the two commonest activities you can observe in birds are feather care / grooming, and feeding/foraging. However, there are a number of other types of behaviour that are also common at certain times of the year or seasons e.g. courting, mating, nest building , song flights, flocking and migration. Part of the information on this page was contributed by EarthLife Please send EcoBirds your comments. Search EcoPort This search facility allows you to search EcoPort directly without having to navigate the more detailed EcoPort menu. EcoPort contains record structures for all birds of the world, and can be searched on scientific or common name in any language (provided it has already been entered). As the bird entities in this knowledge system are relatively new, most records will consist of the scientific name, some taxonomic information, and at least one common name only. This facility can be used to search for any entity type in EcoPort e.g. plants, insects, fungi, bacteria, mammals, birds, and spiders.

89. The Earthlife Web - When And How Do Birds Migrate Article discussing the varying strategies adopted by birds in finding their way when taking part in their long distance journeys. http://www.earthlife.net/birds/migration2.html

When and How do Birds Migrate Birds tend to commence migration in large numbers only when they have a favourable tail wind. In North America the winds north in spring and south in autumn are ideal to assist seasonal migrations. Once started however only very bad weather will stop them. Many birds fly high when migrating because of prevailing winds at higher altitudes and also because the cold at these altitudes helps them disperse all the heat being generated by their flight muscles. Many species of wildfowl fly at 6,000m and some have been observed flying at 8,000m, 86mph in temp = -48 degrees C. Not all birds from a summer breeding site overwinter at the same area. What happens, come autumn, if a male bird meets a female bird in the breeding grounds who has a different overwintering site? Whose site do they go to now they are a pair? In many species the pair bond breaks up at the end of the breeding season, but some like swans mate for life. In the case of the Bewick's Swan the male decides where to fly to for the winter and the female follows him. However, the female decides when it is time to travel back to the tundra for another year's breeding. The reverse scenario is when birds with different breeding sites overwinter in the same area; if pairing commences on the overwintering ground, whose breeding ground to they return to. The answer may be different for different species. The only example I know of involved Mallards in the USA and in this case the male followed the female.

90. Chicken Embryo A number of fine photographs of the development of a chick inside the egg. http://www.microscopy-uk.org.uk/mag/artnov04macro/mlchicken.html

CHICKEN EMBRYO Gallus gallus The Chicken embryo is a staple educational tool in developmental biology.Their availability and similarities with mammalian embryo, help shape our present understanding of embryology. After 21 days of incubation, the chick attempts to break out of its shell, pushing its beak through the air cell. Since the specimens were received out of the egg and without its yoke, I lacked the ability to document the chicken’s interaction in its element. The specimens document a range from 5, 6, 9, 12, to 18 days of development. PHOTOGRAPHING THE EMBRYO SUPPLIES camera two sets of fiber optic lights glass cell approx. 5"x5" water that has sat out in the open for 1 day black velvet fabric large enough to cover the bottom of the glass cell PROCEDURES The chicken embryo is a semi-transparent and monotone subject. The transparent flesh lends itself well to back light, which causes the skin to appear to glow. The choice of background is a crucial prop that helps determine the success of the image for its application. For scientific and documentation purposes, black is the best choice to contrast the flesh tone embryo and emphasize its subtle details. Using a white background makes the translucent skin difficult to distinguish between the subject and its background. However, done correctly, a white background can produce an aesthetically pleasing photo, articulating its neutral tones. The chicken embryo if filled with fluids. If taken out of the water, its delicate cavities will collapse, loosing the significance of its bodily form. Photographing the embryo through water maintains its structure. A second advantage of photographing the embryo under water removes any specular highlights while diffusing the light that falls on the subject. However, the diffusion does reduce the contrast. Bumping up the contrast either through the lighting technique or through the digital file will be helpful.

91. The Making Of An Egg, VME-21-04 Describes the development of the egg of a bird from the release of a mature ovum to the completed egg with shell being laid. http://ohioline.osu.edu/vme-fact/0021.html

Ohio State University Extension Fact Sheet Veterinary Preventive Medicine 1900 Coffey Rd., Columbus, OH 43210 The Making of an Egg VME-21-04 Sara J. Spiegle B.S. Avian Disease Investigation Laboratory Aaron J. Ison B.S. Avian Disease Investigation Laboratory Dr. Teresa Y. Morishita DVM, Ph.D., Dipl. ACVP The egg is the most complete source of nutrients available to humans. It provides protein, vitamins, and minerals and is the only food that contains all essential amino acids. For one egg to be produced it takes approximately 24 hours. Egg production is initiated when a mature ovum is released into the infundibulum. At this point, the egg can be fertilized, if there are live sperm present. The egg spends about 15 minutes in the infundibulum. The ovum transcends next to the magnum where a protective, nutritious layer is added (albumen or egg white). There are two layers to the albumen, thick and thin, which serve as a source of niacin, riboflavin, potassium, sodium, and other nutrients. The thick layer is added first and is closest to the yolk. It provides the majority of the riboflavin and protein for the embryo. In addition, the chalazae are added. These rope-like structures, appearing on both sides of the yolk, are designed to hold the yolk in place as it proceeds thru the reproductive tract. The isthmus is the next destination for the egg. Here, two shell membranes are added, providing additional security to the egg from the environment. There is an air pocket that forms between the two shell membranes and the outer shell as a result of cooling.

92. Avian Brain Circuitry Database Searchable database of the regions of a bird s brain. http://www.behav.org/abcd/abcd.php?proc=ares

93. The Mystery Of Bird Migration: Why And How? Article that tries to answer the question of how and why birds migrate. http://www.naturia.per.sg/buloh/birds/migration.htm

Sitemap List of birds on this site List of plants on this site List of animals on this site My homepage The Mystery of Migration Mangrove and wetland wildlife at Sungei Buloh Nature Park Why do birds migrate? The reasons are complex and not fully understood. But a simple explanation is food and a safe place to breed. Birds which breed in the summer in the extreme north such as the Arctic benefit from an abundance of food as plants and insect life flourish in the long daylight hours; and because few large permanent predators can survive the harsh winter. Many birds that breed in the Arctic simply lay their eggs on the ground. Being able to fly, they can avoid the harsh winter conditions, and be the first to arrive to enjoy the summer benefits. In fact, some have suggested that the question should be why don't all birds migrate. Flight gives birds a huge advantage in finding new sources of food and good places to breed, that it is strange that not more birds migrate. How did bird migration routes become established?

94. A Tale Of Two Boobies Biological examination and dissection at the Slater Museum of a booby that strayed to the Pacific Northwest. http://www.pugetsound.edu/x13725.xml

95. Feathers Illustrated article describing how feathers may have evolved and how they develop from a cylindrical feather follicles. http://www.nurseminerva.co.uk/adapt/feathers.htm

96. BirdMinds - Exploring Bird Intelligence Examples of avian intelligence are reviewed for many different bird species, based upon scientific and anecdotal evidence. http://www.birdminds.com

97. The Avian Embryo - Poultryhelp.com Article describing the development of the embryo and how to observe and exhibit it while it is alive and functioning or as a preserved specimen. http://www.poultryhelp.com/avianembryo.html

Your Best Source for Online Poultry Information and Pure Bred Chicken, Guinea Fowl and Quail Hatching Eggs Home About Us What's New Site Map ... SEARCH This page is from Mississippi State University. They have moved it numerous times breaking the link from our website each time. We feel it is an important enough resource that we decided to copy it to PoultryHelp.com in case they decide to delete it from their website. Mississippi State University and Dr. Tom W. Smith Jr., the author, get full credit for this information. The earliest stages of a bird in its egg are amazing and exciting. In only three weeks a small clump of cells that do not seem to resemble any animal species changes into an active, newly hatched chick. A study of this change is educational and interesting and gives us insight into how humans are formed. This publication will help you study the formation of the egg and the avian (bird) embryo, or chick within the egg. This publication includes plans for two small incubators so you can build one. You may buy small commercially-built incubators at stores selling farm and educational supplies. Incubation procedures show you the effects of heat, moisture, and ventilation on the development of the chick embryo. You also learn to hatch other fowl such as turkeys, ducks, quail, and pheasants. This publication describes how to observe and exhibit an avian embryo while it is alive and still functioning or as a preserved specimen.

98. PaulJohnsgardBooks List of all books written by North American ornithologist Dr. Paul Johnsgard of the University of Nebraska in Lincoln. http://pauljohnsgardbooks.tripod.com/

99. NEOORN Details about subscription information for this e-mail group which disseminates data on the biology of Neotropical birds. http://www.museum.lsu.edu/~Remsen/NEOORNintro.html

NEOORN sponsored by the Museum of Natural Science, Louisiana State University para versi—n en castellano presione: NEOORN *** Remembering Paul Coopmans NEOORN is an email bulletin board devoted to disseminating information on the biology of Neotropical birds. Its primary purpose is to improve communication among those working on Neotropical birds. NEOORN is multilingual; most postings are in English or Spanish, but Portuguese and French also welcomed. NEOORN is open to anyone interested in Neotropical birds. As of January 2009, 733 people were subscribed to NEOORN. Frequent general subjects of postings include requests for information on particular bird species or regions, literature relevant to particular topics logistics of working in particular countries, including local contacts, conservation status of particular species, conservation alerts, and job openings. Check recent messages ( http://birdingonthe.net/mailinglists/NEOO.html ) to see examples. NEOLIT : a regular feature of NEOORN is the posting of literature citations for papers relevant to Neotropical ornithology. For details, click: NEOLIT NEOORN has a Facebook group; it's a convenient place to post photos, videos, and to network:

100. CAVNET HOMEPAGE Archived and recent information from this e-mail discussion group for cavity-nesting birds. http://www.cavitynester.org/

Welcome to CAVNET's Home Page CAVITY-NESTING BIRD RESEARCH Serving the scientific community since 1995 WHAT IS CAVNET? CAVNET was established in 1995 to foster scientific discourse concerning cavity-nesting birds. This list has been created for researchers, academics, and others with a common interest in discussing the scientific aspects of cavity-nesting species. CAVNET's current membership is over 400, representing at least 33 countries (see right panel). The list is moderated by Eric L. Walters to ensure that topics remain focused and to prevent spam from being sent to the list. Common topics include the announcement of new publications, literature searches (e.g. nest parasites of cavities), research techniques (e.g. remote inspection devices, climbing gear), etc. To subscribe to CAVNET , please visit http://lists.uvic.ca/mailman/listinfo/cavnet . Any other questions can be directed to the list owner, Eric L. Walters Please note that we have discontinued the use of our old listserv and we now use mailman . Many websites have not updated this recent change. The new website to visit to sign up for CAVNET is here . CAVNET gratefully acknowledges the support of the University of Victoria in British Columbia, Canada for agreeing to host the CAVNET mailing list at no charge for the past 13 years (first with listserv and now with mailman).

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