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Ornithology. Communication Unit. Avian Senses. Birds have highly developed sight - they see into the near ultraviolet spectrum Birds hear better than mammals - they hear ultra-low frequencies They navigate by using the earth’s magnetism. Avian Intelligence.
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Ornithology Communication Unit
Avian Senses • Birds have highly developed sight - they see into the near ultraviolet spectrum • Birds hear better than mammals - they hear ultra-low frequencies • They navigate by using the earth’s magnetism
Avian Intelligence • Avian learning is equal to or better than most mammals • They master complex problems better than most mammals in advanced learning experiments
Avian Intelligence Cont’d • Explain bird experiment • Cats, rabbits, chickens and pigeons do poorly • Dogs and crows solve it immediately
Avian Intelligence Cont’d • Mammals count poorly - 21,000 trials on average to teach a monkey to count • Birds master counting quickly • Ravens and parakeets easily learn to count to 7
Insight Learning • Insight learning is using learned information in a new situation • Egyptian Vultures use rocks to break ostrich eggs
Insight Learning Cont’d • Woodpecker finches in the Galapagos Islands use sticks to dig insects out of trees, logs and stumps
Avian Memory • Birds have a good memory • This is due to a well developed hippocampus
Avian Memory Cont’d • They remember food sources, nest sites and locations of remote wintering grounds • Titmice cache up to 50,000 seeds • Birds may remember as many as 2,000 cache sites up to 9 months
Avian Vision • They see much better than mammals, in some cases they see details 2.5 to 3 times farther than mammals • Their eyes are large - Eagles and owls have eyes as large as humans
Avian Vision Cont’d • Their eyes can be round to flat in shape but have limited movement abilities • They have to move their heads to see different things
Avian Eyes • Eyes are on the sides of their head • They see better to the side than in front of them • They view close objects with one eye at a time
Avian Eyes Cont’d • Using one eye creates a flatter image • The image lacks good depth perception • To counter this they bob their heads rapidly to view the object from two different angles
Color Vision • Birds have very good color vision • It’s probably better than ours because they have cones (color sensitive cells) and colored oil droplets in their eyes that we don’t have
Hearing • Similar to that of mammals • Have special features to protect the inner in diving birds • Have no external ear- some have a funnel depending on their hearing abilities • Some owls have a muscle around the funnel that amplifies sounds
Taste • They probably don’t taste as well as we do • They usually have 25-75 taste buds on their tongue • We have roughly 10,000 taste buds
Smell • Probably not as good as most mammals • Exceptions are turkey vultures and night hunters
Communication • Birds communicate in various ways • Use displays for mating and territorial defenses • Have specific means for species recognition, locating each other and warning each other of danger
Visual Communication • Color patterns can communicate several things • Drab colors are great for concealment (think woodcock) • Bright colors are for gaining attention, which could mean various things
Visual Identity • Often use head and face color patterns • Imprinting of species identification takes place early, as a chick in the nest
Colors and Contrast • Solid colors are more conspicuous • Contrasting edges make noticeable signals • Regular repetition of shapes gain attention also
Species Recognition • Head patterns seem to be a key for most species • They learn to identify species at an early age, usually in the nest
Species Recognition • Determines mate selection • Offspring of white snow geese choose white mates and offspring of blue geese choose blue mates
Human Imprinting • Wild birds raised by humans will associate them as their family • Often young are raised with puppets to avoid this
Individual Recognition • Use plumage patterns, size, voice and behavior
Displays • Repetitive behaviors that usually are a combination of visual and vocal communication
Displays • Displays seem to be inherited behaviors. The closer the relation, the more similar the behavior • Ex: Throat kinking of anhingas and cormorants
Ritualized Behavior • Repeated behaviors specific to a species • Ritualized feeding is a good example • Males bow, spread wings and give a food call
Precision • These behaviors are usually very precise • Ex: Common goldeneyes “head throw” lasts 1.3 sec with a standard deviation of 0.08 sec
Indication of Intent • Ritualized behavior can indicate the intentions of a bird • Ex: When stellars jays raise their crest, they warn enemies that they are about to attack
Variety of Displays • Many species have more than one display • Great blue herons have 15 that mean everything from breeding intent, territorial marking, switching incubation shifts and pair bonding
Agonistic Behavior • A complex mixture of aggression and escape behaviors • Two birds are interacting, both have a selfish interest • It can lead to hostility or cooperation • They use these to avoid contact and injury
Agonistic Behaviors • They emphasize the bill and wings as weapons
Vocal Communication • Birds have the greatest sound producing abilities of all vertebrates • Work well for communicating over long distances, at night and in dense cover
Recognition • Distinct calls and songs allow birds to determine the senders species and individual recognition