Instruct: Given a question, retrieve documents that answer the question.
Query: What do blue-footed boobies eat?
The natural breeding habitats of the blue-footed booby are the tropical and subtropical islands of the Pacific Ocean. It can be found from the Gulf of California down along the western coasts of Central and South America down to Peru. Approximately one half of all breeding pairs nest on the Galápagos Islands. Its diet mainly consists of fish, which it obtains by diving and sometimes swimming underwater in search of its prey. It sometimes hunts alone, but usually hunts in groups.
The blue-footed booby usually lays one to three eggs at a time. The species practices asynchronous hatching, in contrast to many other species whereby incubation begins when the last egg is laid and all chicks hatch together. This results in a growth inequality and size disparity between siblings, leading to facultative siblicide in times of food scarcity. This makes the blue-footed booby an important model for studying parent–offspring conflict and sibling rivalry.
These birds probe with their bill in mud or shallow water, also picking up food by sight. They mainly eat insects, crabs and other small aquatic animals.
"Phytoplankton are eaten by zooplankton - small animals which, like phytoplankton, drift in the ocean currents. The most abundant zooplankton species are copepods and krill: tiny crustaceans that are the most numerous animals on Earth. Other types of zooplankton include jelly fish and the larvae of fish, marine worms, starfish, and other marine organisms". In turn, the zooplankton are eaten by filter-feeding animals, including some seabirds, small forage fish like herrings and sardines, whale sharks, manta rays, and the largest animal in the world, the blue whale. Yet again, moving up the foodchain, the small forage fish are in turn eaten by larger predators, such as tuna, marlin, sharks, large squid, seabirds, dolphins, and toothed whales.
The red-eared firetail ("Stagonopleura oculata"), also known as the boorin, is a small finch-like species of bird. It occurs in dense wetland vegetation of coastal to sub-coastal regions in Southwest Australia. Its appearance is considered appealing, with white spots, black barring and vivid crimson marks at the ear and upper tail. Red-eared firetails are usually only glimpsed briefly, if at all, as they move rapidly and discreetly through their habitat. Most observations occur when their soft voice is heard, or in flight when flushed from the dense scrub. Males and females are similar in colouring and bond as lifelong pairs that occupy a territory centred on their roosting and brooding nest site. The species occupy a similar ecological niche to the beautiful firetail "Stagonopleura bella" found in the east of Australia, although unlike other species of the genus they only occasionally group together and are almost never seen in large flocks.
The Virginia rail probe with its bill in mud or shallow water, also picking up food by sight. It mainly eat insects and other aquatic invertebrates, like beetles, flies, dragonflies, crayfish, snails and earthworms. It can also eat aquatic animals like frogs, fish and some small snakes, as well as seeds. Animal preys constitute the biggest part of this bird's diet, but vegetation contributes to its diet in the fall and winter.
The grey gum regenerates by regrowing from the base and branches after bushfire. Trees live for over a hundred years. The grey-headed flying fox ("Pteropus poliocephalus") eats the flowers, while the leaves form a staple of the diet of the koala ("Phascolarctos cinereus"). Leaves in winter contain less nitrogen than those in summer, which the koalas make up for by eating more in winter months. The brown-headed honeyeater ("Melithreptus brevirostris") and yellow-tufted honeyeater ("Lichenostomus melanops") have been observed eating gum exudate from the stems. 
Fieldwork at several sites around central New South Wales showed that the red wattlebird ("Anthochaera carunculata") and noisy friarbird ("Philemon corniculatus") preferred to forage on the foliage of the grey gum over other trees, with the former appearing to oust the latter if both species were present.
This subspecies eats geckos, house mice, birds, and marsupials, including the Tammar wallaby.
The young of brooding red-eared firetails, "Stagonopleura oculata", were taken from a nest being observed.
There are over 100 species of birds, of which ten are endemic. Many birds are passing vagrants, such as the great cormorant ("Phalacrocorax carbo"). Others, like the lesser frigatebird ("Fregata ariel"), are more regular visitors. Bird populations are threatened due to the invasive yellow crazy ant, and reports have suggested that the ant has attacked hatchlings and harassed adults in their nests. All endemic bird species have been placed on the critically endangered list.
The yellow-billed oxpecker eats insects and ticks. Both the English and scientific names arise from this species' habit of perching on large wild and domesticated mammals such as cattle and eating arthropod parasites. It will also perch on antelopes such as wildebeest. In a day an adult will take more than 100 engorged female "Boophilus decoloratus" ticks or 13,000 larvae.
The beel is a natural habitat to many varieties of birds. 219 species of birds including more than 70 migratory species are reported in the beel area. The largest congregations of aquatic birds can be seen, particularly in winter, with a reported recorded count of 19,000 water birds in a day. Some of the globally threatened species of birds like spotbilled pelican ("Pelecanus philippensis"), lesser adjutant stork ("Leptoptilos javanicus"), Baer’s pochard ("Aythya baeri"), Pallas' sea eagle ("Haliaeetus leucogaster"), greater adjutant stork ("Leptoptilos dubius").
The birds-of-paradise are members of the family Paradisaeidae of the order Passeriformes. The majority of species are found in eastern Indonesia, Papua New Guinea, and eastern Australia. The family has 42 species in 15 genera. The members of this family are perhaps best known for the plumage of the males of the sexually dimorphic species (the majority), in particular the highly elongated and elaborate feathers extending from the beak, wings, tail or head. For the most part they are confined to dense rainforest habitat. The diet of all species is dominated by fruit and to a lesser extent arthropods. The birds-of-paradise have a variety of breeding systems, ranging from monogamy to lek-type polygamy.
The island is home to a large colony of little penguins on the island. As the island has no foxes or feral cats, the penguins have no predators other than other seabirds and seals. With the restoration of native habitat and the provision of penguin breeding boxes, penguin numbers have increased, and there are now approximately 12,000 on the island. The female usually lays two eggs, and during a good year, both chicks will survive. The birds come ashore at dusk after feeding at sea, and visitors to the island can watch the birds from a platform near the jetty.
Superb fairywrens are predominantly insectivorous. They eat a wide range of small creatures (mostly insects such as ants, grasshoppers, shield bugs, flies, weevils and various larvae) as well as small quantities of seeds, flowers, and fruit. Their foraging, termed 'hop-searching', occurs on the ground or in shrubs that are less than two metres high. Because this foraging practice renders them vulnerable to predators, birds tend to stick fairly close to cover and forage in groups. During winter, when food may be scarce, ants are an important 'last resort' food, constituting a much higher proportion of the diet. Nestlings, in contrast to adult birds, are fed a diet of larger items such as caterpillars and grasshoppers.
This is a bird which breeds in sub-tropical semi-desert with a few trees, such as acacia. It winters in open woodland or grassland. As the name suggests, bee-eaters predominantly eat insects, especially bees, wasps and hornets, which are caught in the air by sorties from an open perch. However, this species probably takes more dragonflies than any other food item. Its preferred hunting perch is telephone wires if available.
During the breeding season, the ruff’s diet consists almost exclusively of the adults and larva of terrestrial and aquatic insects such as beetles and flies. On migration and during the winter, the ruff eats insects (including caddis flies, water-beetles, mayflies and grasshoppers), crustaceans, spiders, molluscs, worms, frogs, small fish, and also the seeds of rice and other cereals, sedges, grasses and aquatic plants. Migrating birds in Italy varied their diet according to what was available at each stopover site. Green aquatic plant material, spilt rice and maize, flies and beetles were found, along with varying amounts of grit. On the main wintering grounds in West Africa, rice is a favoured food during the later part of the season as the ricefields dry out.
An immense number of bird species live in the Amazon rainforest and river basin (an area which is nominally home to one out of every ten known species of animal). Over 1,300 of these species are types of birds, which accounts for one-third of all bird species in the world. The diets of rainforest birds greatly differ between species, although, nuts, fruits and leaves are a common food for many birds in the Amazon. Birds migrate to the Amazon rainforest from the North or South. Amazon birds are threatened by deforestation since they primarily reside in the treetops. At its current rate of destruction, the rainforest will be gone in forty years. Human encroachment also negatively affects the habitat of many Amazonian birds. Agriculture and road clearings limits the habitable areas. Birds in the Amazon are distinguished by which layer of the rainforest they reside in. Each layer or community has unique plants, animals and ecosystems. Birds interact with other animals in their community through the food chain, competition, mating, altruism and symbiosis.
New Zealand has a high proportion of ground-nesting and flightless birds, due to its long geographical isolation and a lack of mammal predators. Native birds have evolved to fill niches that are occupied by mammals in most other places. Stoats are the greatest threat to these ground-nesting and hole-nesting birds, which have very limited means of escaping stoat predation. In some areas the whio population is now 70% male, from stoats attacking female ducks incubating eggs.
The Blue Hole is an attraction on the island of Big Pine Key in the Florida Keys. It is an abandoned rock quarry that was used for nearby road fills and Henry Flagler's Overseas Railroad. The water it contains is mostly fresh and is used by various wildlife in the area, such as birds, snakes, alligators, key deer and green iguanas. It is part of the National Key Deer Refuge.
Many cuckoos are obligate brood parasites, meaning they only lay eggs in other birds' nests and never take care of their own young. Birds that do this, such as the common cuckoo or the brown-headed cowbird, lay relatively small eggs because their expected hosts are usually smaller birds. Cuckoos in the genus "Coccyzus", lay relatively large eggs even though they still parasitize smaller birds. Yellow warblers are the smallest birds recorded caring for black-billed cuckoo eggs. In experiments, these wood warblers were found to accept the cuckoo eggs 63% of the time even though their own eggs are only a quarter of the size. Even with the size difference, the warbler parent is often still able to raise the cuckoo as long as it can provide the chick with sufficient nutrition and incubation.
The black-billed cuckoo was originally placed in genus "Cuculus". This genus comprises Old World cuckoos that are all obligate brood parasites. Upon further genetic testing, it was placed into genus "Coccyzus" that comprises nine species of New World cuckoos. The black-billed and yellow-billed cuckoos are the only two that migrate into North America while the other seven are permanent residents of either Central or South America. Even though these two cuckoos overlap in range, they are not sister taxa. This suggests that the two species invaded North America separately. Although family Cuculidae is monophyletic, the genus "Coccyzus" was found to be polyphyletic.
Gerrids, or water striders, are preyed upon largely by birds and some fish. Petrels, terns, and some marine fish prey on Halobates. Fish do not appear to be the main predators of water striders, but will eat them in cases of starvation. Scent gland secretions from the thorax are responsible for repelling fish from eating them. Gerrids are largely hunted by birds of a wide range of species dependent on habitat. Some water striders are hunted by frogs, but they are not their main food source. Water striders are also sometimes hunted by each other. Water strider cannibalism involves mainly hunting nymphs for mating territory and sometimes for food. To escape predators, water striders will either fly away to a neighboring pond or dive under water. This avoidance of predation aids the dispersal process and thus spread of a species over a larger area of land. As species encounter new areas of land, they adapt to new environments. There are so many species of water strider partially as a result of this dispersion and adaptation over time.
The American oystercatcher feeds almost exclusively on shellfish and other marine invertebrates. Oysters are a staple of their diet, as their name suggests, but they also eat mussels, clams, limpets, sea urchins, starfish, crabs, and worms. In general, they use their bills to catch shellfish. As they walk across a shellfish bed, they look for a mollusk with a partially opened shell. When they find one, they jab their bill into the shell and sever the muscle that causes the shell to clamp shut. This can be dangerous, however, as they are sometimes drowned when they don't completely severe this muscle and the shell clamps down on their bill. A strong, tightly rooted mollusk can hold the bird in place until the tide comes in. They also feed by carrying loose shellfish out of the water and hammering at the shell or by probing the sand for soft-shell or razor clams.
Blue-footed boobies are less likely to commit siblicide and if they do, they commit it later after hatching than masked boobies. In a study, the chicks of blue-footed and masked boobies were switched to see if the rates of siblicide would be affected by the foster parents. It turns out that the masked boobies that were placed under the care of blue-footed booby parents committed siblicide less often than they would normally. Similarly, the blue-footed booby chicks placed with the masked booby parents committed siblicide more often than they normally did, indicating that parental intervention also affects the offspring's behavior.
Blue-footed booby parents are passive spectators of this intrabrood conflict. They do not intervene in their offspring's struggles, even at the point of siblicide. Booby parents even appear to facilitate the demise of the younger sibling by creating and maintaining the inequality between the two chicks. They reinforce the brood hierarchy by feeding the dominant chick more often than the subordinate one. Thus, they respond to the brood hierarchy and not to the level of begging when deciding which chick to feed, as both chicks beg in equal amounts. This level of passivity towards the very possible death of their younger offspring may be an indication that brood reduction is advantageous for the parents. The "Insurance Egg Hypothesis" views the second egg and resulting chick as insurance for the parent in case the first egg does not hatch, or if food levels are higher than expected.
Red-footed boobies are spectacular divers, plunging into the ocean at high speeds to catch prey. They mainly eat small fish or squid which gather in groups near the surface.
Plunge diving can be done from heights of and even up to . These birds hit the water around and can go to depths of below the water surface. Their skulls contain special air sacs that protect the brain from enormous pressure. Prey are usually eaten while the birds are still underwater. Individuals prefer to eat on their own instead of with their hunting group, usually in the early morning or late afternoon. Males and females fish differently, which may contribute to why blue-foots, unlike other boobies, raise more than one young. The male is smaller and has a proportionally larger tail, which enables the male to fish in shallow areas as well as deep waters. The female is larger and can carry more food. Both the male and female feed the chicks through regurgitation.