question: What are the redtail hawks that live on my property trying to tell each other when they start squawking back and forth? Are they checking in with each other? Telling them they saw prey? Or just gossiping in bird talk about their day?
comment: According to the [Birds of North America website]( URL_0 ), the hawks' nesting/mating season is about to begin, so... Realistically? A good amount of that chatter is probably some hawk booty-calls.
passages: Around five separate communication calls of the red-eared firetail had been reported by the late twentieth century, these have been classified in several ways from reports in the field or aviary. Adult vocalisation is distinguished as an identity call, intimate nest-calls, a nest-site call, and a contact or communication call (Pepper, Immelmann) only reported in captives. Additional records in aviculture are for huffing, distress, aggression and alarm calls. The volume of their calls is low, so only heard nearby, and the communication at the nest site is very soft.
   Section::::In mammals.
  
  Though rarely documented in mammals, a few instances of distraction display have appeared in the literature. One researcher documented a distraction display performed by a female red squirrel in order to protect her young. When the nest was approached, the female attempted to lead the researcher away through the trees using a ventriloquistic call that resembled the cries of the young. An additional study documented distraction display in Mentawai langurs, whereby a male will call loudly and bounce on branches while the female and young are able to quietly hide.
  
  Section::::Costs and decision to display.
   A study on the little green bee-eater suggests that these birds may be able to see from the point of view of a predator. The brown-necked raven has been observed hunting lizards in complex cooperation with other ravens, demonstrating an apparent understanding of prey behavior. The California scrub jay hides caches of food and will later re-hide food if it was watched by another bird the first time, but only if the bird hiding the food has itself stolen food before from a cache. A male Eurasian jay takes into account which food his bonded partner prefers to eat when feeding her during courtship feeding rituals. Such an ability to see from the point of view of another individual and to attribute motivations and desires had previously been attributed only to the great apes and elephants.
   Additionally, it has been shown that some predators are “smart,” or have learned to recognize that distraction displays indicate a nearby nest. One study recorded a red fox that increased its searching behavior in response to the distraction display of a grouse and eventually found and killed the grouse nestlings.
  
  Section::::Costs and decision to display.:Factors influencing decision.
   In Peru's Cocha Cashu Biological Station, radio-collared individuals rested during the day in dens below large trees or other sheltered sites on the ground. They started to be active earliest in the late afternoon and moved between 3.2 and 17 hours until latest dawn, when they returned to their dens. Their usual pace of walking was about per hour when hunting. They moved up to per hour when heading to a known kill site or patrolling their territory.
   Delayed response tasks are often used to study short-term memory in animals. Introduced by Hunter (1913), a typical delayed response task presents an animal with a stimulus such a colored light, and after a short time interval the animal chooses among alternatives that match the stimulus, or are related to the stimulus in some other way. In Hunter's studies, for example, a light appeared briefly in one of three goal boxes and then later the animal chose among the boxes, finding food behind the one that had been lighted. Most research has been done with some variation of the "delayed matching-to-sample" task. For example, in the initial study with this task, a pigeon was presented with a flickering or steady light. Then, a few seconds later, two pecking keys were illuminated, one with a steady light and one with a flickering light. The bird got food if it pecked the key that matched the original stimulus.
   There was once a pigeon who made a nest in a tree and laid an egg in it. When the egg was ready to hatch, a fox came to the foot of the tree and demanded that the pigeon give him the newborn chick to eat. This continued for the next egg too. One day a heron passed by the pigeon and advised it to challenge the fox to climb the tree and take the eggs himself. The next time the fox came, the pigeon acted on the heron's advice. The fox, stumped, asked the pigeon where it learnt such a retort. The pigeon informed the fox of her teacher the heron. The fox approached the heron, who had nested near the river. The fox asked the heron to show him how it could tuck its head under its wing. While the heron displayed this, the fox attacked the heron and killed it, all the while mocking the heron for providing the pigeon with a trick, but not being smart enough to avoid the fox's trick.
   Snipe in the genera "Gallinago" and "Lymnocryptes", as well as the closely related woodcocks "Scolopax", make courtship display flights, at dusk and on moonlit nights, producing mechanical sounds called "drumming", "bleating" or "winnowing", through the vibration of their modified outer tail feathers caused by the rush of air in the course of a power dive. Of his research in the Chatham Islands Miskelly wrote:
  
  and:
   Section::::Behavior.:Vocalization.
  
  The usual call is a series of eight accented hoots ending in "oo-aw", with a downward pitch at the end. The most common mnemonic device for remembering the call is "Who cooks for you, who cooks for you all." It is noisy in most seasons. When agitated, this species will make a buzzy, rasping hiss and click its beak together forcefully. While calls are most common at night, the birds do call during the day as well.
  
  Section::::In art.
   There was once a pigeon who made a nest in a tree and laid an egg in it. When the egg was ready to hatch, a fox came to the foot of the tree and demanded that the pigeon give him the newborn chick to eat. This continued for the next egg too. One day a heron passed by the pigeon and advised it to challenge the fox to climb the tree and take the eggs himself. The next time the fox came, the pigeon acted on the heron’s advice. The fox, stumped, asked the pigeon where it learnt such a retort. The pigeon informed the fox of her teacher the heron. The fox approached the heron, who had nested near the river. The fox asked the heron to show him how it could tuck its head under its wing. While the heron displayed this, the fox attacked the heron and killed it, all the while mocking the heron for providing the pigeon with a trick, but not being smart enough to avoid the fox’s trick.
   BULLET::::- A hen leaves her eggs unguarded, and a mean-looking weasel stealthily creeps into the henhouse while the narrator frets. Just as he is about to grab the eggs, they all hatch at once, and the chicks shout "BOO!" in unison. The frightened weasel evokes a Joe Penner catch-phrase, "Don't ever DOOO that!" and gasps as his heart pounds.
  
  BULLET::::- An owl is hooting dully until it briefly smiles while saying "Who's Yehoodi?"
   Many birds follow strict time schedules in their activities. These are often dependent upon environmental cues. Birds also are sensitive to day length, and this awareness is especially important as a cue for migratory species. The ability to orient themselves during migrations is attributed to birds' superior sensory abilities, rather than to intelligence.
  
  Section::::Studies.:Beat induction.
  
  Research published in 2008 that was conducted with an Eleonora cockatoo named Snowball has shown that birds can identify the beat of man-made music, an ability known as beat induction.
  
  Section::::Studies.:Self awareness.
   Distraction displays were once considered to be a sort of "partial paralysis," or uncontrolled, stress-induced movements. On the basis of several observations, David Lack postulated that such displays simply resulted from the bird's alarm at having been flushed from the nest and had no decoy purpose. He noted a case in the European nightjar, when a bird led him around the nest several times but made no attempt to lure him away. He additionally noted courtship displays mixed with the distraction displays of the bird, suggesting that distraction display is not a purposeful action unto itself, and observed that the display became less vigorous the more frequently he visited the nest, as would be expected if the display were a response driven by fear and surprise.
   In one study, ravens were tested in two rooms separated by a wooden wall. The wall had two functional windows that could be closed with covers; each cover had a peephole drilled into it. In the next familiarization step, the ravens are trained to use a peephole to observe and pilfer human-made caches in the adjacent room. Under test conditions, there was no other raven present in the adjacent room, however, a hidden loudspeaker played a series of sounds recorded from a competitor raven. The storing raven generalized from their own experience when using the peephole to pilfer the human-made caches and predicted that the audible (raven) competitors could potentially see their caches through the peep-hole and took appropriate action, i.e. the storing ravens finished their caches more quickly and they returned to improve their caches less often. The researchers pointed out that this represented "seeing" in a way that cannot be reduced to the tracking of gaze cues – a criticism leveled at many other studies of ToM. The researchers further suggested that their findings could be considered in terms of the "minimal" (as opposed to "full-blown") ToM recently suggested.
   BULLET::::- Hovering – using quickened wing beats, often in times of increased winds, the birds will search the ground and drop on the prey.
  
  BULLET::::- Cooperative Hunting – mates have been known to assist each other.
  
  BULLET::::- Piracy – the ferruginous hawk has been observed gathering around a hunter shooting prairie dogs, and to claim shot "dogs" by flying to them and mantling over them.
   Members of the corvid family have been known to watch other birds, remember where they hide their food, then return once the owner leaves. Corvids also move their food around between hiding places to avoid thievery, but only if they have previously been thieves themselves (that is, they remember previous relevant social contexts, use their own experience of having been a thief to predict the behavior of a pilferer, and can determine the safest course to protect their caches from being pilfered). Studies to assess similar cognitive abilities in apes have been inconclusive.
   The center also studies the alarm calls of wild Capuchin monkeys in Ometepe, Nicaragua. Capuchin monkeys produce alarm call relative to the predator Previous surveys show two distinct families of alarm calls - those dealing with terrestrial predators and those dealing with aerial predators. Alarm calls focused on human threats fall into the aerial category. A sample of over 1500 alarm call vocalizations from a group of previously unstudied wild Capuchin monkeys were recorded on Ometepe island in Nicaragua during the summer of 2008. The calls were analyzed for spectral peak frequencies and onset 
   Ruffed lemurs use alarm calls that differentiate between ground and aerial predators. For instance an "abrupt roar" or "huff" alerts the group to an avian predator, and a "pulsed squawk" or "growl-snort" communicates the existence of a mammalian ground predator. When sounding these calls, such as the pulsed squawk, adults direct them at the predator after moving to a safe position. Once the alarm call is sounded by one individual, the resulting chorus can even reach the furthest ranging community members.
  
  In captivity, ruffed lemur vocalizations have been studied and divided into three general groups: high-, medium-, and low-amplitude calls.
   The role of the calls of "Burhinus" is poorly understood due to the difficulty of observation of individuals while calling. Eurasian stone-curlews are the best studied and it has been found that:
  
  BULLET::::- groups are more vocal than pairs;
  
  BULLET::::- vocals may be more important between adjacent pairs than within the pair;
  
  BULLET::::- more vocal in pre-lay period, silent when newly arrived in breeding territory, quiet again before chicks arrive and until fledging;
  
  BULLET::::- more daytime calling occurs while establishing a territory or from unpaired or non-breeding birds, and these birds are more easily attracted by call playback.
   Some research with ravens provides an example of evidence for theory of mind in a non-human species. Ravens are members of the corvidae family, which is widely regarded as having high cognitive abilities. These birds have been observed to hide their food when dominant ravens are visible and audible at the same time. Based on this observation, ravens were tested for their understanding of "seeing" as a mental state. In a first step, the birds protected their cache when dominants were visible but not when they could only be heard from an adjacent room. In the next step, they had access to a small peephole which allowed them to see into the adjacent room. With the peephole open, the ravens guarded their caches against discovery when they could hear dominants in the adjacent room, even when the dominant's sounds were playbacks of recordings.
   Timeline of ornithology
  
  The following is a timeline of ornithology events:
  
  Section::::Until 1700.
  
  BULLET::::- 1500–800 BC – The Vedas mention the habit of brood parasitism in the Asian koel ("Eudynamys scolopacea").
  
  BULLET::::- 4th century BC – Aristotle mentions over 170 sorts of birds in his work on animals. He recognises eight principal groups.
  
  BULLET::::- 3rd century BC – The "Erya", a Chinese encyclopedia comprising glosses on passages in ancient texts, notably the Book of Songs, features 79 entries in its chapter "Describing Birds"
   Sun compass in animals
  
  Many animals are able to navigate using the Sun as a compass. Orientation cues from the position of the Sun in the sky are combined with an indication of time from the animal's internal clock.
   Section::::Published works.
  
  BULLET::::- 1998: "Episodic-like memory during cache recovery by scrub jays"
  
  BULLET::::- 2001: "Effects of experience and social context on prospective caching strategies in scrub jays"
  
  BULLET::::- 2004: "The mentality of crows. Convergent evolution of intelligence in corvids and apes"
  
  BULLET::::- 2006: "Food-caching western scrubjays keep track of who was watching when"
  
  BULLET::::- 2007: "Planning for the future by Western Scrub-Jays"
  
  BULLET::::- 2009: "Western scrub-jays conceal auditory information when competitors can hear but cannot see"
   Section::::Behavior.
  
  Section::::Behavior.:Communal roosting.
  
  Crows gather in large communal roosts numbering between 200 and tens of thousands of individuals during nonbreeding months, particularly in the winter. These gatherings tend to happen near large food sources such as garbage dumps and shopping centers. 
  
  Section::::Behavior.:Play.
  
  Countless incidents are recorded of corvids at play. Many behaviourists see play as an essential quality in intelligent animals.
  
  Section::::Behavior.:Calls.
   Hawkwatchers usually use binoculars, spotting scopes, and cameras to aid in the identification of the flying raptors. Unlike other forms of birding, auditory cues are rare, for many raptors do not vocalize in flight. Instead, hawkwatchers rely on shape, flight behavior, and plumage to identify the raptors as they pass the hawk site. Several books specialize in learning hawk identification, which is usually challenging because of the distances and the speed at which the raptors are migrating. "Hawks At A Distance" and "Hawks From Every Angle" by Jerry Liguori specifically helps hawkwatchers identify raptors that are high in the sky, at odd angles, and appearing unusually small. Unlike typical field guides, these books attempt to help understand the motion of the bird, its temperament, and personality, something that is most significantly described in "Hawks in Flight" by Dunne, Sibley, and Sutton as gestalt.
  