Bee-Eaters (Meropidae)

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Bee-eaters

(Meropidae)

Class Aves

Order Coraciiformes

Suborder Alcedines

Family Meropidae


Thumbnail description
Small to medium-sized, active, colorful, sociable birds with long, slender, decurved bills and a characteristic upright, alert posture when perched

Size
6–10.5 in (15–27 cm)

Number of genera, species
3 genera; 24 species (22 species recognized by some taxonomists)

Habitat
Savanna, open woodlands, and desert-scrub, rarely forests

Conservation status
Not threatened

Distribution
Paleotropics

Evolution and systematics

Taxa in the bee-eater family are morphologically rather homogeneous, and their affinities with the other five families in the Alcedines suborder are more distant than the affinities those families share with each other. C. Hilary Fry, a recognized authority on bee-eater biology and evolution, recognizes three genera and 24 species. Analyses by Charles Sibley and Burt Monroe Jr. in the 1990s, using the technique of DNA-DNA hybridization, suggested only minor adjustments; they demote two species recognized by Fry to subspecies.

The genus Nyctyornis seems the most primitive and may point to the evolutionary roots of bee-eaters. Although the family is most diverse in Africa, the restricted distribution of Nyctyornis, in forested southeast Asia, suggests that the family originated in this region.

Physical characteristics

Bee-eaters are a family of small to medium-sized active birds, primarily of open habitats. They are easy to see in many parts of the paleotropics because of their striking color patterns and acrobatic flights to capture prey. Nearly all bee-eaters have beautiful plumages, typically with bright gourgets of red or yellow that contrast with blues and ochres of the breast and belly. Eye stripes bordered with contrasting colors are nearly ubiquitous. Two of the largest species, the carmine (Merops nubicoides) and rosy bee-eaters (Merops malimbicus), are a brilliant magenta or pink over most of the body.

All bee-eaters share the characteristics of a strong, slightly decurved bill, and a foot structure that includes the partial fusion of the three forward-facing toes. In most species the sexes are very similar or identical in appearance. Juveniles may have distinguishing plumage for a short time.

Distribution

Southern and southeastern Europe, sub-Saharan Africa, Arabian Peninsula, south and Southeast Asia, Indonesia, Philippines, Papua New Guinea, and Australia.

Habitat

Most bee-eaters favor open grasslands, dry scrub habitats, and large openings in woodlands, but there are a handful of little-known forest dwellers scattered from western Africa to southeast Asia and the island of Sulawesi, Indonesia. With few exceptions, even the forest species are usually found near openings, along river courses, and at road cuts.

Behavior

With few exceptions, bee-eaters are gregarious and social. Only about five species are likely completely solitary. Fifteen species are colonial or loosely colonial. Physical body contact is not common among birds, but with bee-eaters it is characteristic. A branch catching the early morning sun will attract first one, then another, and finally a whole family of bee-eaters

that will huddle closely together, all facing into the sun. Colony sites are centers of high activity, and there is a cacophony of sound as family members greet each other, fuss over the proximity of intruders to their nesting hole, or fight to remove an unwanted visitor.

Complex social relationships might be quite common among bee-eaters, particularly those with sedentary populations, but few species have been studied in enough detail to

know for certain. Detailed studies of the white-fronted bee-eater (Merops bullockoides) in Kenya by Stephen Emlen, Robert Hegner, and Peter Wrege revealed one of the most complex societies known for any species of bird.

Populations of white-fronted bee-eaters spend the entire year roosting together at a colony that may contain from 30 to 450 birds, and the population is structured into extended family groups or "clans" that include several generations. During the non-breeding season, all members of a clan, as many as 15 individuals, may roost together in one burrow at the colony. For breeding, clans often split up into nuclear family sub-groups. Members of a clan interact frequently, joining and greeting one another on perches near the colony, roosting together, or visiting each other's roosting burrows.

Feeding ecology and diet

All bee-eaters appear to be specialists in eating bees and other venomous hymenoptera. Studies of the diet of more than 15 species show that 60–80% of the diet is honeybees, wasps, and ants. But they will also pursue nearly any insect of suitable size, provided it is flying. A few species forage occasionally for large insects and small lizards on the ground, and there are even observations of bee-eaters catching small fish. A few larger species forage mainly on the wing, but most beeeaters are "sit-and-wait" hunters, scanning the habitat from a perch with their keen eyes, chasing down likely prey with a flight that may take them even 150–180 ft (50–60 m) from their perch, then returning in a flash of color to subdue the prey for consumption.

Bee-eaters have stereotyped behaviors for dealing with prey—and they clearly recognize those with potentially dangerous venom and sting. After repeatedly smacking the head of the prey item against a perch, the bee-eater juggles the insect's body in its bill, biting along the abdomen from near the middle (thorax) toward the tip. This behavior often expresses a droplet of venom from the bee or wasp. Then the bee-eater wipes the tip of the insect's abdomen back and forth across the perch in a behavior known as "bee-rubbing." Many times this behavior pulls the stinger and poison gland out of the prey item.

Reproductive biology

Reproduction in bee-eaters depends on the species. Some have solitary nesting by unaided pairs, while others have extremely dense colonies with complex social structures and cooperative breeding. Cooperative breeding, which involves assistance by non-breeding adults, may be the rule rather than the exception. Seventeen species are known or suspected to be cooperative breeders.

All bee-eaters dig their own nesting burrows into soil or sand, and burrows may be 1.5–9 ft (0.5–3 m) in length, depending on the species and soil type. Thirteen species dig nests into nearly flat ground or into banks along rivers, irrigation ditches, erosion gullies, and even into roofs of aardvark or warthog dens.

The family structure and helping behaviors of the white-fronted bee-eater were studied in great detail and will serve as a complex example of cooperative breeding. The basic elements likely apply to all bee-eater species with cooperative breeding, although in some species family groups may be less complex. Helpers are often associated with all aspects of the reproductive attempt, from helping to dig the nesting burrow to incubating eggs and feeding nestlings. The most important function of helpers is in bringing food to the nestlings and recently fledged offspring. In Kenya, one helper could nearly double the number of offspring produced by a pair. Thus the ability to attract a helper could make a significant contribution to the reproductive output of a breeder.

Many helpers are young unpaired sons (and sometimes daughters) of the breeding pair, but if an older pair fails in

their nesting attempt, they may become helpers at the nest of a son or grandson.

In addition to benefits that a helper gains by increasing the production of close relatives, sometimes a bit of selfish reproduction is possible as well. It is common for a young female helper, nearly always the daughter of the breeding pair, to slip one of her own eggs into the nest of her parents.

Conservation status

Not threatened.

Significance to humans

In Australia, the arrival of the rainbow bee-eater (Merops ornatus) heralds the arrival of the rainy season, and in Africa huge colonies of rosy bee-eaters are a source of great pride to people in nearby villages. However, bee-eaters hold little significance to humans apart from the enjoyment that comes from observing their beauty and aerial antics. On all shores of the Mediterranean, those who make a living from the honey of the bee Apis mellifera have considered the European bee-eater (Merops apiaster) a pest, despite little scientific evidence that honey production is ever seriously compromised by bee-eater predation.

Species accounts

List of Species

Blue-bearded bee-eater
Purple-bearded bee-eater
Black bee-eater
White-fronted bee-eater
White-throated bee-eater
Rainbow bee-eater
European bee-eater
Carmine bee-eater

Blue-bearded bee-eater

Nyctyornis athertoni

taxonomy

Merops athertoni Jardine and Selby, 1830, India. Two subspecies.

other common names

French: Guêpier à barbe bleue; German: Blaubartspint; Spanish: Abejaruco Barbiazul.

physical characteristics

12.5–13.5 in (31–34 cm); 2.5–3.3 oz (70–93 g). The largest bee-eater and, along with its congener, clearly differentiated from the other genera by a stouter bill and a lax beard of feathers running from the base of the bill to the lower breast. Upperparts mainly green; belly is buff with broad green streaks. Forehead is pale azure-blue; long, broad throat feathers are dark blue grading to azure on the tips.

distribution

India to Indochina, but absent from the Malay Peninsula.

habitat

Clearings and more open areas of deep forest, occurring at elevations up to 7,150 ft (2,200 m), where it inhabits moss and deciduous forests.

behavior

Birds spend most of their time in pairs, perched at the top of or at the outer side of trees, in search of food.

feeding ecology and diet

Relatively little is known, but honeybees, wasps, large beetles, and dragonflies are commonly taken. The blue beard may act

as a flower mimic, attracting honeybees close enough to be snapped up by birds without moving from the perch.

reproductive biology

Solitary nester, digging nesting burrows up to 9.75 ft (3 m) into stream or road banks. In India and Nepal, there are two breeding periods, February to May and August to October. In Indochina, egg laying is most common in April to May, but breeding may occur anytime until October. Clutch size is six eggs.

conservation status

Not threatened.

significance to humans

None known.


Purple-bearded bee-eater

Meropogon forsteni

taxonomy

Meropogon forsteni Bonaparte, 1850, Celebes. Monotypic.

other common names

English: Celebes bee-eater; French: Guêpier des Célèbes; German: Celebesspint; Spanish: Abejaruco del Célebes.

physical characteristics

10 in (25–26 cm), excluding tail streamers up to 2.5 in (6 cm). No weights available. Upperparts and wings are green; lower belly is dark brown; tail feathers are green and russet. Forehead and crown are blackish; ear-coverts, nape, and sides of

neck are chocolate to dark vinous-brown; long, broad throat feathers are purple and overlap the breast.

distribution

The most restricted species in the family, occurring only on the island of Sulawesi, Indonesia.

habitat

Open areas of rainforest.

behavior

Sedentary or near-migrant. May travel to coasts for rainy seasons, and return inland for dry seasons.

feeding ecology and diet

Forages from mid- and upper-canopy perches for bees, wasps, beetles, and dragonflies.

reproductive biology

Few records available, but active nests have been found in April, July, September, and December, so breeding may occur in nearly any month.

conservation status

Not threatened.

significance to humans

None known.


Black bee-eater

Merops gularis

taxonomy

Merops gularis Shaw, 1798, Sierra Leone. Two subspecies.

other common names

French: Guêpier noir; German: Purpurspint; Spanish: Abejaruco Negro.

physical characteristics

8 in (20 cm); 0.85–1.0 oz (24–30 g). Particularly striking and distinctive plumage, with nearly entirely black head and black back with contrasting scarlet throat and azure-blue rump.

distribution

West Africa from Sierra Leone west through Central Africa to eastern Zaire.

habitat

Clearings and stream edges in rainforest, secondary forest, wooded farmland, and gallery forest, usually high above the ground.

behavior

Sedentary or partial migrant. Appears to be some movement corresponding to wet and dry seasons.

feeding ecology and diet

Usually forages high in the tree canopy.

reproductive biology

Poorly known. Usually a solitary breeder; small colonies have been observed in Sierra Leone and Liberia. Breeding occurs from March to May.

conservation status

Not threatened.

significance to humans

None known.


White-fronted bee-eater

Merops bullockoides

taxonomy

Merops bullockoides A. Smith, 1834, Marico River, South Africa. Sometimes considered a subspecies of M. bullocki. Monotypic.

other common names

French: Guêpier à front blanc; German: Weissstirnspint; Spanish: Abejaruco Frentiblanco.

physical characteristics

8.5–9.5 in (22–24 cm); 1–1.4 oz (28–38 g). Upperparts and wings are blue-tinged green; underparts are buff; thighs and undertail coverts are blue; spread tail is green above and blackish below. White forehead, cheeks, and chin are sharply defined from the black mask and red throat.

distribution

Occurs south of the forested Congo basin across the breadth of Africa. Locally common north along the Rift Valley in Kenya to Lake Turkana, and on the west side of Lake Tanganyika north to Rwanda.

habitat

Occupies wooded savannas.

behavior

Among the most social of all bee-eaters, roosting and breeding in large colonies (up to 400 nests) and interacting in extended family groups throughout its life. Sedentary in Kenya, but may

move widely during the non-breeding season in the southern range.

feeding ecology and diet

Family groups or clans defend foraging territories up to 4.5 mi (7 km) from the roosting/breeding colony. Within territories, members of the clan spend most of the time spaced apart on favorite perches, from which they make sallies for insect prey.

reproductive biology

Throughout most of the range, breeding begins at the end of the dry season, August to October. In Kenya, where there are two somewhat unpredictable rainy periods, egg-laying may begin in October to November, or April to May, but any given population breeds during only one season. Clutch size is two to five eggs.

Cooperative breeding is common. Sixty percent of nests have one or more helpers (up to five), usually males.

conservation status

Not threatened.

significance to humans

None known.


White-throated bee-eater

Merops albicollis

taxonomy

Merops albicollis Vieillot, 1817, Senegal. Monotypic.

other common names

French: Guêpier à gorge blanche; German: Weisskehlspint: Spanish: Abejaruco Gorgiblanco.

physical characteristics

8 in (19–21 cm), excluding tail-streamers which can exceed

4.75 in (12 cm); 0.7–1 oz (20–28 g). The black crown and mask, separated by white supercilliary, cheeks, and throat make this species unmistakable. Hindneck is ochre; back is green; rump and tail are bluish; breast is pale green; belly is white. Longest tail streamers in the family.

distribution

Northern tropics, breeding across sub-Saharan Africa in very dry habitats, wintering in forested areas to the south, across the continent.

habitat

Occupies thorn scrub, open sandy dunes, and river washes during breeding, but rainforest canopy, woodlands, and orchards during the winter.

behavior

Gregarious and vocal, this species is a conspicuous daytime migrant between desert breeding grounds and wet forests of tropical Africa, where it spends the non-breeding season flycatching from the canopy. Individuals wintering near the Zaire River must migrate nearly 1,400 mi (2,200 km) to the nearest breeding locations.

feeding ecology and diet

The diet is unusual, with a high proportion of flying ants, especially in forested habitats. White-throated bee-eaters will take ground prey such as lizards, tenebrionid beetles, and grasshoppers, and also forage in continuous flight like many of the larger bee-eaters. Most peculiar is an association with squirrels feeding on the oil palm Elaeis guineensis. Squirrels strip and discard the oily pericarp from the fruits, and beeeaters snatch these nutritious pieces as they fall from high in the palm crown.

reproductive biology

Breeds in loose colonies on flat or tiered ground surfaces from February to October (the later months in Chad and Nigeria).

Clutch size averages six eggs. Helping behavior is well developed. In one study, 90% of nests were attended by one or more non-breeding adults—the highest frequency of helping known for any bee-eater species.

conservation status

Not threatened.

significance to humans

None known.


Rainbow bee-eater

Merops ornatus

taxonomy

Merops ornatus Latham, 1801, New South Wales, Australia. Monotypic.

other common names

English: Rainbow bird; French: Guêpier arc-en-ciel; German: Regenbogenspint; Spanish: Abejaruco Australiano.

physical characteristics

7.5–8 in (19–21 cm), excluding tail streamers, which are 0.8 in (2 cm) in females and up to 2.8 in (7 cm) in males; 0.7–1.2 oz (20–33 g). Males are mainly glossy green with azure rump and uniquely black tail. Crown and nape are bronze; broad, black eyestripe is bordered below by pale blue band; chin and cheeks are yellow; throat is rufous; triangular gorget is black. Females are similar, but hind crown is less bronzy and tail streamers are shorter and wider.

distribution

Occurs throughout Australia, except most of the central arid region, and locally in Papua New Guinea. Winters in northern Australia, New Guinea, as well as the Indonesian islands west to Lombok and north to Sulawesi.

habitat

Open habitats of almost all descriptions, perhaps determined mostly by availability of nesting sites.

behavior

Gregarious outside of the breeding season, roosting and feeding in flocks, but aggregated only in loose colonies during breeding.

feeding ecology and diet

Primarily bees, wasps, and other hymenopterans. Also takes beetles, flies, moths, dragonflies, damselflies, and an occasional spider. Prey is captured on wing after being spotted from a perch.

reproductive biology

Breeding in northern areas is underway by late August or September, but in southern Australia not until November and December. Nest burrows are usually dug into flat or gently sloping ground, with occasional use of low banks. Clutch size averages five eggs.

Roughly 15% of pairs are helped by one or more male helpers.

conservation status

Not threatened. Populations may be increasing as a consequence of open habitats being created by human activity.

significance to humans

None known.


European bee-eater

Merops apiaster

taxonomy

Merops apiaster Linnaeus, 1758, Southern Europe. Monotypic.

other common names

French: Guêpier d'Europe; German: Bienenfresser; Spanish: Abejaruco Europeo.

physical characteristics

9–10 in (23–25 cm), excluding tail streamers of 0.8 in (2 cm);1.6–2.8 oz (44–78 g). Very distinctive multi-colored plumage. Sexes distinguishable in breeding plumage, with females paler in coloration overall.

distribution

Northwest coast of Africa from Morocco to Libya, Mediterranean islands, countries of the northern Mediterranean east through the Middle East to Pakistan, northern India and Afghanistan. A small breeding population in South Africa and Namibia is largely disjunct from the wintering distribution, which extends from Lake Victoria in Kenya, south to the Transvaal, and west to Angola.

habitat

Grasslands, open woodlands, pasturelands with scattered trees, and gallery forests in drier habitats.

behavior

Gregarious at all times of year, breeding in colonies and remaining in flocks on wintering grounds.

feeding ecology and diet

Forages primarily from a perch, as is typical of most bee-eaters, but also feeds for considerable periods in continuous flight.

reproductive biology

Sometimes a solitary nester, it is more commonly found breeding in colonies, some with as many as 400 nests. Egg-laying occurs during May in the southern part of the range, and June and early July in Russia. South African populations begin breeding in October. Clutch sizes are the largest of any bee-eater, with up to 10 eggs, generally five or six.

Cooperative breeding is common, with about 20% of nests having a helper.

conservation status

Not threatened.

significance to humans

Probably the most persecuted bee-eater, particularly wherever apiculture (bee-keeping) is an important industry. It is considered a pest in much of its range.


Carmine bee-eater

Merops nubicoides

taxonomy

Merops nubicus Gmelin, 1788, Nubia. Two subspecies.

other common names

English: Southern carmine bee-eater: French: Guêpier carmin; German: Karminspint; Spanish: Abejaruco Carmesí.

physical characteristics

9.5–10.5 in (24–27 cm), excluding tail streamers of up to 4.75 in (12 cm); 1.2–2.1 oz (34–59 g). Upperparts are predominantly carmine with contrasting beryl-green crown, chin, cheeks, and rump. Black mask. Throat is olive-green but appears azure to greenish blue against the light. Belly is carmine shading to azure on undertail-coverts.

distribution

Disjunct distribution in Africa. Occurs from Senegal to Somalia, north of the Congo Basin. In winter, these northern birds move south into Sierra Leone, Nigeria, Cameroon, or across

the continent to Uganda, Kenya, and Tanzania. In the south, they occur from the Okavango headwaters in Angola east to Mozambique, south into northern Botswana and southern Zimbabwe. Non-breeding birds spread into northeast South Africa and the Transvaal and north into Angola, southern Zaire, Burundi, and west Tanzania.

habitat

Savannas, open woodlands, lakeshores, and mangroves in coastal regions.

behavior

Has three-stage migration pattern in northern and southern tropics. In the southern tropics, from breeding grounds, travels south from December onward, and back north in March to August, until breeding season. In the northern tropics, the birds move north following breeding.

feeding ecology and diet

Nearly all food is taken in continuous flight. The bird is common at bush fires, where it swoops above the leading edge to capture fleeing insects. In northeastern savannas, it sometimes associates with large ungulates and large cursorial birds (e.g., ostrich, bustards), using their backs as a perch from which to sally after insects disturbed by grazing animals.

reproductive biology

Large breeding colonies of 100–1,000 nests are common. Nests occur in cliffs or on flat ground, where colonies are often larger—2,000–3,000 nests. North of the equator, egg-laying occurs from February to May (later farther north), and in the southern tropics from September to November.

Cooperative breeding has not been confirmed, although casual observations suggest it is likely.

conservation status

Not threatened.

significance to humans

None known.


Resources

Books

Fry, C. Hilary. The Bee-Eaters. Vermillion: Buteo Books, 1984.

Fry, C. Hilary, et al. Kingfishers, Bee-eaters and Rollers: A Handbook. Princeton: Princeton University Press, 1992.

Sibley, Charles G., and Burt L. Monroe Jr. Distribution and Taxonomy of Birds of the World. New Haven, CT: Yale University Press, 1990.

Periodicals

Bell, H. L. "Abundance and Seasonality of the Savanna Avifauna at Port Moresby Papua New-Guinea." Ibis 124(1982): 252–274.

Crick, H. Q. P., and C. H. Fry. "Effects of Helpers on Parental Condition in Red-throated Bee-eaters Merops bullocki." Journal of Animal Ecology 55 (1986): 893–906.

Dyer, M., and H. G. P. Crick. "Observations on White-throated Bee-eaters Merops albicollis Breeding in Nigeria." Ostrich 54 (1983): 52–55.

Emlen, Stephen T., and Peter H. Wrege. "Breeding Biology of White-fronted Bee-eaters at Nakuru Kenya: The Influence of Helpers on Breeder Fitness." Journal of Animal Ecology 60(1991): 309–326.

Emlen, Stephen T., and Peter H. Wrege. "Gender, Status and Family Fortunes in the White-fronted Bee-eater." Nature 367, no. 6459 (1994): 129–132.

Garnett, S. "Mortality and Group Cohesion in Migrating Rainbow Bee-eaters (Merops ornatus)." Emu 85 (1985): 267–268.

Hegner, R. E. et al. "Spacial Organization of the White-fronted Bee-eater (Merops bullockoides)." Nature 298, no. 5871 (1982): 264–266.

Karthikeyan, S., and J. N. Prasad. "Recent Sighting of Bluebearded Bee-eater (Nyctyornis athertoni) (Jardine and Selby)." Journal of the Bombay Natural History Society 90, no. 2 (1993): 290–291.

Lessells, C. M. et al. "Why Do European Bee-eater (Merops apiaster) Brothers Nest Close Together?" Behavioral Ecology 5 (1994): 105–113.

Lessells, C. M. et al. "Individual and Sex Differences in the Provisioning Calls of European Bee-eaters." Animal Behaviour 49 (1995): 244–247.

Lill, Alan. "Breeding of Rainbow Bee-eaters in Southern Victoria." Corella 17 (1993): 100–106.

Saffer, V. M., and M. C. Calver. "The Size and Type of Prey Taken by Adult Rainbow Bee-eaters in the South-west of Australia." Emu 97 (1997): 329–332.

Salewski, Volker, and Mark O. Roedel. "Fish Eating by Redthroated Bee-eaters, Merops bullocki." Ostrich 71 (2000):425.

Sridhar, S., and Karanth K. Praveen. "Helpers in Cooperatively Breeding Small Green Bee-eater (Merops orientalis)." Current Science Bangalore 65 (1993): 489–490.

Wrege, Peter H., and Stephen T. Emlen. "Breeding Seasonality and Reproductive Success of White-fronted Bee-eaters in Kenya." Auk 108 (1991): 673–687.

Wrege, Peter H., and Stephen T. Emlen. "Family Structure Influences Mate Choice in White-fronted Bee-eaters" Behavioral Ecology and Sociobiology 35 (1994): 185–191.

Peter H. Wrege, PhD