Ceryle rudis

Geographic Range

Pied kingfishers ( Ceryle rudis ) occur in sub-saharan African, the Middle East, the Asia mainland, and southern China. They are common in sub-saharan Africa, along the Nile, and east Egypt. In Pakistan, they are widely distributed across Punjab and the Sind plains. They are rare in Cyprus, Greece, and Poland.

• Biogeographic Regions
• palearctic palearctic
  • native native
• oriental oriental
  • native native
• ethiopian ethiopian
  • native native

Habitat

Pied kingfishers live along streams, lakes, rivers, estuaries, irrigation ditches, canals, bays, floodlands, and reedy inlets. Near mountainous areas, they live in lower river valleys. They usually avoid mangroves and large swamps. The habitat of C. rudis ranges from seashores up to 2,500 m above sea level. They are less abundant near fast flowing waters.

One study shows that there is a distinct difference in habitat use between males and females. Females are more common in rocky shores and are less abundant in beach shorelines which primarily results from breeding patterns. Along rocky shorelines, nests are built closer to the shore. Since females spend more time incubating eggs than males, they have more access to the shore if nest sites are closer to the shoreline.

• Habitat Regions
• tropical tropical
• terrestrial terrestrial

• Aquatic Biomes
• lakes and ponds
• rivers and streams
• temporary pools
• coastal coastal

• Wetlands
• swamp swamp

• Other Habitat Features
• riparian riparian
• estuarine estuarine

Physical Description

Ceryle rudis is a medium-sized kingfisher and has the distinctive kingfisher body type, with a large head, small body, small feet, and long, dagger-like bill. They have distinctive black and white coloration, spotted on the wings, and with a black crown on the head.

There are no size differences between male and female birds. The average male is 82.4 g with a bill length of 48.8 mm, and the average female is 86.4 g with a bill length of 48.4 mm. Body mass ranges from 70 to 100 g. Sexes can be distinguished by sexually dimorphic bands across the chest. Males characteristically have two black bands whereas females have only one. The typical body length is 25 to 29 cm, wing length is 13.3 to 14.2 cm, and tail length is 6.6 to 7.4 cm

Young pied kingfishers are similar to adult females, but with the lores, chin, throat, and breast feathers tipped with brown. The bill is shorter and the breast band is greyish black.

Four subspecies of C. rudis have been recognized. These include C. r. rudis , C. r.travancoreensis , C .r. leucoelanura , and C.r.insignis . The geographic range of C. r. rudis consists of sub-saharan Africa, the Nile valley, southern Turkey, and Israel. The geographic range of C. r. travancoreensis is southwest India. These subspecies can be distinguished because C. r. travancoreensis has blacker upper feathers and smaller white spots than C. r. rudis , and its bill can be up to 10 mm longer. Ceryle rudis leucoelanura is similar to C. r. travancoreensis but is smaller and with lighter black spots. It occurs throughout the rest of India, Sri Lanka, northeast Afghanistan, and the Kashmir and Himalayan mountains of India and China. The remaining sub-species, C. r. insignis , is found in Hong Kong, Hainan, and China. It is similar to C. r. leucoelanura but the bill is about 5 mm longer on average.

Pied kingfishers may be confused with crested kingfishers ( Megaceryle lugubris ), also called greater pied kingfishers. Crested kingfishers, unlike pied kingfishers, have a pink brown lining on the wings instead of a white lining. They are also much larger than pied kingfishers.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• sexes colored or patterned differently

Reproduction

Courtship involves dancing displays and males offering food to females. Dancing displays are gregarious and done with 3 to 12 males at one time. They noisily call to each other while holding their wings half spread and may also engage in fights by interlocking their beaks or holding their wings. Males attract females by offering food over a period of about three weeks. Pied kingfishers breed cooperatively, with non-mated birds helping raise the offspring of a mated pair. Cooperative breeding begins before eggs hatch, but more males help the breeding pair after hatching.

• Mating System
• monogamous monogamous
• cooperative breeder cooperative breeder

Pied kingfishers breed in winter in northern and southern parts of their range and breed in any month near the equator. Pairs are monogamous, and both sexes assist in digging nest holes in soft earth. Pied kingfishers build nests by using their beaks to dig into the ground and their feet to push dirt out of the nest. Nests can be built alone or colonially with up to 100 other birds building nests in the same area. They are built along creeks and rivers and take 23 to 26 days to complete. Colonial nesting is more common in Africa than in India. Eggs are laid at intervals of one day and begin three days after burrow completion. Eggs are glossy, white and round. Incubation takes eighteen days, and a typical clutch contains five eggs. In order to protect the eggs, about 80% of nest holes are actually false starts that do not lead to the egg chamber. Hatchlings will be fed by parents for up to two months after fledging, but will begin diving for food two weeks after fledging. Young kingfishers will grow their flight feathers between eleven and thirteen days after hatching.

• Key Reproductive Features
• iteroparous iteroparous
• seasonal breeding seasonal breeding
• year-round breeding year-round breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• oviparous oviparous

Males and females, along with other males, will share the duties of raising nestlings and incubating eggs. Still, females are the primary incubators during the day and usually incubate at night. Nestlings will be nurtured for 23 to 26 days. Pied kingfishers typically have several male breeder-helpers per nest of two kinds: primary and secondary. Usually there is only one primary helper, most often these are sons of the breeding male. This helper focuses on feeding the nestlings. Secondary helpers are unrelated and show up a few days after the nestlings hatch. They are at first warded away, but eventually are tolerated and focus on feeding the female. Sex ratios in C. rudis are biased, with about 79% males, which promotes this helper behavior.

Before fertilization, male parental investment involves offering food to females in the courtship ritual. This prepares the female to reproduce by providing her with more resources. Throughout fertilization, incubation, fledging, and weaning, males and females will protect the nest from predators with vocalizations and threat behaviors.

Young hatch blind, pink, and helpless. Their eyes open by the ninth day and they begin to grow feathers by the fourth day. Flight feathers begin to grow between the 11th and 13th days, and fully develop six weeks after leaving the nest. Nestlings will leave the nest on the 25th day, and are fed by the parents for 1 to 2 months. They begin diving within 2 weeks of leaving the nest. In caring for their young, pied kingfishers will often feed their nestlings whole fish. They regurgitate one pellet of undigested bones per day.

There is no sanitation at the nest, which becomes covered with liquid feces. To compensate for this, chicks peck at the walls of the nest and cover their droppings with soil.

• Parental Investment
• altricial altricial
• pre-fertilization
  • provisioning
  • protecting
    • male
    • female
• pre-hatching/birth
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-weaning/fledging
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• pre-independence
  • provisioning
    • male
    • female
  • protecting
    • male
    • female
• post-independence association with parents
• extended period of juvenile learning

Lifespan/Longevity

Little is known about the lifespan of pied kingfishers, but their mortality increases as a result of human interference. Water pollution or changes in water habitat reduces the number of nesting sites for kingfishers and nestlings can die from flooding of the nest. Also, bioaccumulation of pollution and toxins in fish affects the mortality rates of kingfishers. Kingfishers have relatively high reproduction rates, compensating for increased mortality in some areas.

Behavior

Pied kingfishers are gregarious, tame, and conspicuous. They perche on the sides of streams on waterside vegetation to conserve energy. They also perch on manmade objects such as fences, canoes, and huts. Ceryle rudis creates communal roosts at certain times of year, and are the largest birds able to hover for a sustained period of time.

Characterist behaviors include the exhibition of a regular bobbing of the head or tail. They bathe by repeatedly diving into water, fly without undulation, and rarely hunt on land. Noisy chirps are uttered in flight or to mark territory during nesting. Individuals live in pairs or loosely tied families. They do not migrate.

• Key Behaviors
• fossorial fossorial
• flies
• glides
• diurnal diurnal
• motile motile
• sedentary sedentary
• solitary solitary
• territorial territorial
• social social
• colonial colonial

Home Range

There is little known about the home range of C. rudis , but on average 9 to 16 birds can coexist on 1 km of shoreline. They hunt for food and forage within 50 m of water.

Communication and Perception

Kingfishers have a specialized vision system for detecting movement. Kingfishers are also able to see a wide angle of view, which helps with watching for prey. They have excellent color vision and can see into the ultraviolet range.

Vocalizations are varied and important for declaring territory and attracting mates, so C. rudis is often heard before it is seen. They are most noisy when performing courtship dances. During dances they will make a repeated “werk……werkwerkwerk” noise. Other calls include anxiety calls, a low pitch “jerp,” and threat calls, a staccato “chikerkerker….”

• Communication Channels
• visual visual
• tactile tactile
• acoustic acoustic

• Other Communication Modes
• duets duets
• choruses choruses

• Perception Channels
• visual visual
• ultraviolet
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

Pied kingfishers primarily eat fish. Unlike other kingfishers, pied kingfishers swallow their fish in flight after plunging. This mode of ingestion makes it difficult to identify species eaten by the kingfisher, but observed prey include Cyrtocara eucinostomus , Cichlid species, Pseudotropheus zebra , Engraulicypris argenteus , Haplochromis species, Barbus species, Gilchristella aestuarius , Ambassis nataalensis , and Hyporhamphus knysnaensis . Pied kingfishers may also take aquatic insects, crustaceans, and ,more rarely, amphibians and mollusks. Adults will regurgitate three to four pellets of undigested bones per day, but hatchlings will digest most of the bones and regurgitate only one pellet per day, absorbing more calcium to support their own bone growth.

There are 3 foraging behaviors displayed by C. rudis : hover-plunge, perch-plunge, and skimming. Hover-plunge occurs when a bird leaves a perch and progressively flies to lower and lower heights until it finally plunges into the water to pierce the prey. Perch-plunge is a tactic in which the bird sits on a perch waiting for a fish to swim close enough so that it can plunge directly into the water after a fish. With this method, a bird will increase its perch height with an increased depth of water. A skimming bird will fly close to the water about 100 m offshore, but little is known about this process because it is difficult to gather data on this hunting method. Still, this method makes pied kingfishers unique because they are the only species of kingfisher that will forage offshore. Pied kingfisher families have been seen to perch together when fishing, but these family units will often split up. Capture success rate is only 9 to 50%. More successful plunges usually take half the time of unsuccessful plunges.

Environmental conditions affect which type of fishing behavior birds use. In windier conditions, C. rudis will use hover-plunge 80% of the time and perch-plunge 20% of the time. In calm conditions, these statistics reverse. Perch availability is also a limiting resource. Pied kingfishers usually implement perch-plunge along a rocky shore or where many perches are available. Hover-Plunge, on the other hand is more common on sandy beaches.

Pied kingfishers can compensate for the refraction index of water by increasing their acceleration and dive angle as the depth of the prey increases. Their nictitating membrane helps to protect their eyes from the water as they enter at high speeds.

Food specialization reduces competition between pied kingfishers and other species. Each species of bird eats a different size fish and larger birds perch on higher spots. This allows many types of fish-eating bird species to exist in the same territory by lowering competition for food resources and perching spots.

• Primary Diet
• carnivore carnivore
  • piscivore piscivore

• Animal Foods
• amphibians
• fish
• insects
• mollusks
• aquatic crustaceans

Predation

Pied kingfishers are preyed upon by lanner falcons ( Falco biarmicus ). Both adults and young are preyed on by the cobras ( Naja ) and mongooses Herpestes . Nestlings are preyed on by safari ants ( Dorylus nigricans ), snakes , and small, predatory mammals. Defense of the nest involves threat displays such as half raising the wings, fanning the tail, and loud, vigorous vocalizations. Also, entire colonies will attack predators which try to enter nests.

Ecosystem Roles

Pied kingfishers are major predators of fish. There is some evidence for a mutualistic relationship with clawless otters ( Amblonyx ).

Economic Importance for Humans: Positive

In Nigeria, pied kingfishers are kept as pets and become tame after one week. They are free to roam with children after that time but some return to the wild. Some pied kingfishers are eaten in this area as well.

• Positive Impacts
• food food

Economic Importance for Humans: Negative

Pied kingfishers may interfere with fishing operations, including angling, fish stocking, or fish farming.

• Negative Impacts
• crop pest

Conservation Status

Pied kingfishers are not currently threatened. They are rather abundant and are the most common species of kingfisher throughout their range. Although they may benefit from human dams and fish farming, they are at risk of poisoning through bioaccumulation of pollution and toxins in their fish prey.

Additional Links

Encyclopedia of Life

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Sarah Sirajuddin (author), Kalamazoo College, Ann Fraser (editor, instructor), Kalamazoo College.

References

Cramp, S., R. Douthwaite, H. Reyer, K. Westerturp. 1988. Ceryle rudis (Linnaeus). Pied Kingfisher. Alcyon pie.. Pp. 299-302 in The Birds of Africa Volume III , Vol. 3. San Diego: Academic Press.

Fioratti, P. 1992. Kingfisher . London: Harper Collins Publishers.

Fry, H., K. Fry. 1992. Kingfishers Bee-eaters & Rollers . Princeton: Princeton University Press.

Johnston, D. 1989. Feeding ecology of pied kingfishers on Lake Malawi, Africa. Biotropica , 21/3: 275-277.

Kemp, A. 2002. Kingfishers (Alcedinidae), Pied Kingfisher. Pp. 5-10, 23 in Grzimek's Animal Life Encyclopedia , Vol. 10/Birds III, 2 Edition. Farmington Hills: Gale Group.

Line, L. 1995. Kings and Pretenders. International Wildlife , 25: 30-37.

Maclean, G. 1985. Robert's Birds of Southern Africa . London: New Holland Publishers Ltd..

Rayner, J., U. Norberg, M. Brooke. 1991. Movement, A survey of modern birds. Pp. 62, 111 in The Cambridge Encyclopedia of Ornithology , Vol. 1/1, 1 Edition. New York: The Press Syndicate of the University of Cambridge.

Reyer, H., W. Migongo-Bake, L. Schmidt. 1988. Field studies and experiments on distribution and foraging of pied and malachite kingfishers at Lake Nakuru (Kenya). The Journal of Animal Ecology , 57/2: 595-610.

Roberts, T. 1991. The Birds of Pakistan . Karachi: Oxford University Press.

Terres, J. 1980. Kingfisher Family. Pp. 563-565 in The Audobon Encyclopedia of North American Birds , Vol. 1/1, 1 Edition. New York: Alfred A. Knopf.