Merops apiasterEuropean bee-eater

Geographic Range

European bee-eaters (Merops apiaster) have a broad distribution covering much of Europe and Africa with range estimates up to 11,000,000 square km. These migratory birds can be found as far north as Finland and range as far south as South Africa, extending east into some Asiatic countries as well. Most commonly, European bee-eaters will breed and nest in southern Europe, then migrate south during autumn and winter. (BirdLife International 2009, 2009; White, et al., 1978)

Habitat

European bee-eaters are commonly found near freshwater systems and inhabit a variety of habitat types such as forest, savanna, shrubland, grassland, and agricultural areas. The habitat for nesting can be specific involving only river systems or gravel pits with steep exposed banks. European bee-eaters have also been found to dig burrows directly into the ground. Food availability can determine the habitat occupied by European bee-eaters. Many agricultural fields use bee-hives for pollination and M. apiaster will frequent those areas. (BirdLife International 2009, 2009; White, et al., 1978; Yosef, et al., 2006; BirdLife International 2009, 2009; White, et al., 1978; Yosef, et al., 2006)

Physical Description

European bee-eaters are mid-sized insectivores that have dark, thick, and slightly downward curved bills. A bright yellow chin and throat patch meet a blue chest that extends down to the flanks and belly. Dark lores and eye-stripe are contrasted by a white patch above the upper mandible and lower white eye-stripe extending from the lower mandible. A dark chestnut color covers the crown and nape, becoming lighter in color on the back. Upper tail coverts are variable, ranging from green to blue, with most of the tail being blue. Wing lengths average 44 cm for males and 49 cm for females. Weights of European bee-eaters are similar in males and females and range from 44 to 78 g. Total body length ranges from 27 to 30 cm.

Males and females, very similar in coloration, can be distinguished by the hue of the greater coverts, being a chestnut in males and greenish-blue in females, and by the median coverts, where males are a chestnut and females have a greenish hue. Juveniles can be distinguished from adults by the color of the iris. In mature adults the iris is a vibrant red and juveniles will have a grayish-olive-red color. Also, the chestnut color found in adults is only green in juveniles. (Lessells and Ovenden, 1989; Yosef, et al., 2006)

  • Sexual Dimorphism
  • sexes alike
  • Range mass
    44 to 78 g
    1.55 to 2.75 oz
  • Average mass
    52 g
    1.83 oz
  • Range length
    27 to 30 cm
    10.63 to 11.81 in
  • Average length
    28 cm
    11.02 in
  • Range wingspan
    44 to 49 cm
    17.32 to 19.29 in
  • Average wingspan
    46 cm
    18.11 in

Reproduction

European bee-eaters are monogamous and will generally stay together from year to year if both survive. Courtship feeding has been observed of some male European bee-eaters, where the male will bring food to the female a couple days before, during, and after egg laying. Roughly 20% of nesting pairs have 1 to 4 helpers that exhibit cooperative breeding, where a non-breeding male, likely a close relative, will assist the nesting pair by sitting on the nest and catching prey for young. (Avery, et al., 1988; Hoi, et al., 2002; Horváth, et al., 1992)

In central Europe, most European bee-eaters return to their breeding range in late April or early May. They will mate in May and dig out burrows around 1 m deep in sand pits or steep river banks. Females lay 4 to 7 eggs in late May to early June. They are laid in 2 day intervals and incubated 3 to 4 weeks before hatching asynchronously. Before young fledge asynchronously at around 4 weeks of age they undergo weight loss to reduce their weight closer to that of an adult. Asynchronous Hatching and fledging is thought to help offset sibling rivalry and allow better care of young with a variable food source like flying insects. Juveniles become independent at 1 to 2 months of age. Sexual maturity is reached within the first year, though juveniles are not always successful at breeding in their first year. Juveniles may come back to the same colonies and nest near relatives such as parents or siblings. These juveniles may become family helpers if they fail to nest.

They are either solitary or colonial nesters. One study found a negative effect on nest success with increasing colony size. Isolated pairs with equal clutch size had a higher rate of nesting success. It is thought that colonial breeding could still be worthwhile if it increases adult survival. (Avery, et al., 1988; Lessells and Avery, 1989; Lessells and Ovenden, 1989)

  • Breeding interval
    European bee-eaters breed once yearly.
  • Breeding season
    European bee-eaters breed between May and June.
  • Range eggs per season
    4 to 7
  • Average eggs per season
    5
  • Range time to hatching
    3 to 4 weeks
  • Range fledging age
    28 to 32 days
  • Range time to independence
    1 to 2 months
  • Average age at sexual or reproductive maturity (female)
    1 years
  • Average age at sexual or reproductive maturity (male)
    1 years

Both male and female European bee-eaters participate in excavating the underground nesting burrow. After the eggs are laid, the pair shares incubation responsibilities. Chicks are born altricial, without feathers and eyes closed, and rely on significant parental care for survival. The male "helper" will also share incubation and feeding duties, but is not as reliable as the breeding pair. Both parents provide food and protection for young until fledging. Some male European bee-eaters will continue to feed the female for several days during and after egg laying.

European bee-eaters exhibit very specific feeding behaviors that are difficult for young birds to learn. Breeding pairs will continue to feed fledglings until the young learn the skills to successfully forage for themselves. (Lessells and Avery, 1989; Lessells, et al., 1994)

  • Parental Investment
  • altricial
  • male parental care
  • female parental care
  • pre-fertilization
    • provisioning
    • protecting
      • 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

European bee-eaters have been documented to live up to 5.9 years in the wild. ("Merops apiaster Linnaeus 1758", 2009)

  • Range lifespan
    Status: wild
    5.9 (high) years

Behavior

European bee-eaters are migratory, diurnal birds that spend most of their time foraging for food. It is common to see them sitting at a perch scanning for prey, then flying out catching a prey item and coming back to the perch to subdue and consume it. These birds are often found nesting in colonies, but may also nest singly as well. Mixed colonies of European bee-eaters and blue cheeked bee-eaters (Merops persicus) can be found foraging together without competition because of minimal diet overlap. (Burton and Burton, 2002; Kossenko and Fry, 1998)

  • Range territory size
    0.7 to 8 m^2

Home Range

Often found in colonies, territories are formed 0.7 to 8 m around nesting sites during breeding season.

Communication and Perception

The family Meropidae (bee-eaters), most species being colonial, often will exhibit interspecific and intraspecific communication. Like most colonial species, European bee-eaters are very vocal while within the colony. Pairs often call to locate or otherwise communicate to each other. European bee-eaters have a limited repertoire, which consists of several, slight variations on a "preep" call. This call is given in rapid succession while in social groups, and takes on a "bubbly" characteristic during courtship.

European bee-eaters have been found to exhibit intraspecific “helping”. A nesting pair may accept a third party to help with incubating or feeding to increase nesting success. This social communication may be between related individuals and help fitness.

Mixed flocks of European bee-eaters and blue cheeked bee-eaters (Merops persicus) have been found to have better breeding success as a result of mixed species foraging offsetting interspecific competition. Interspecific communication has also been found to be defensive during nesting, involving fighting and avoidance, whereas intraspecific communication included sunning, preening, and mobbing of predators. The benefit of being a social communal species is having more eyes on the lookout for danger; European bee-eaters will use vocal communication to warn others about danger.

Like all birds, European bee-eaters perceive their environment through visual, auditory, tactile and chemical stimuli. (Kossenko and Fry, 1998; Petrescu and Adam, 2001; White, et al., 1978)

Food Habits

As their name implies, European bee-eaters' diet consists of bees ranging in size from large to small (Hymenoptera), but also includes dragonflies (Ondonata) and other flying insects. Bee-eaters are quick on the wing and agile for catching flying insects. When catching insects they will grasp them by the midsection, fly back to perch, and hit them against their perch until movement ceases. When catching stinging insects they will immobilize them and hit the sting against the perch to pull or rip it out, and then toss the prey up vertically to swallow. Breeding pairs of European bee-eaters continue to feed their fledglings until the young birds learn to successfully catch and eat insects. (Burton and Burton, 2002; Krebs and Avery, 1984)

  • Animal Foods
  • insects

Predation

Montpellier snakes (Malpolon monspessulanus), ocellated lizards (Timon lepidus), and black kites (Milvus migrans) are common predators of European bee-eaters. Nestlings are most vulnerable because ground burrows are easily accessed by snakes and lizards. (Burton and Burton, 2002)

Ecosystem Roles

European bee-eaters are known as ecosystem engineers because of their effects on arid environments through burrowing breeding behavior. Three ways have been suggested regarding how European bee-eaters impact the environment: (i) burrowing and soil removal allows rain, sunlight, and nutrients to penetrate soil. (ii) abandoned burrows provide shelter for other species to colonize the area (iii) deep burrows provide access to invertebrate prey items which can increase food web complexity.

The microclimate that is created by these burrows can be significantly different from the macroclimate. Some species that re-use burrows made by European bee-eaters include European rollers (Coracias garrulus), little owls (Athene noctua), pied wagtails (Motacilla alba), and rock sparrows (Petronia petronia).

Analysis of active European bee-eaters' nests detected several species of mites (chicken mites, tropical fowl mites) and larvae of Diptera, beetles (Tenebrionidae family), and moths and butterflies (Lepidoptera order). (Casas-Crivlle and Valera, 2005)

Commensal/Parasitic Species

Economic Importance for Humans: Positive

European bee-eaters have not been recorded as a species that benefits humans in an economic manner. They are unique and beautiful birds that attract many birders and photographers.

Economic Importance for Humans: Negative

European bee-eaters are seen as a pest by many farmers in central and southern Europe. These birds are attracted to high densities of cultivated bees, and are frequently persecuted by farmers. European bee-eaters may cause significant damage to a hive if they prey upon the queen. (Al-Ghzawi, et al., 2009)

  • Negative Impacts
  • crop pest

Conservation Status

European bee-eaters are listed as a species of least concern by IUCN. Although their numbers have been declining over the past decade, the population (480,000 to 1,000,000 breeding individuals) is still well above any level of threat. (BirdLife International 2009, 2009)

Contributors

Tyler Petroelje (author), Northern Michigan University, Alec Lindsay (editor), Northern Michigan University, Rachelle Sterling (editor), Special Projects.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

cooperative breeder

helpers provide assistance in raising young that are not their own

desert or dunes

in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.

diurnal
  1. active during the day, 2. lasting for one day.
endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

female parental care

parental care is carried out by females

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

insectivore

An animal that eats mainly insects or spiders.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

male parental care

parental care is carried out by males

migratory

makes seasonal movements between breeding and wintering grounds

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

soil aeration

digs and breaks up soil so air and water can get in

solitary

lives alone

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5? N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

References

2009. "Merops apiaster Linnaeus 1758" (On-line). Encyclopedia of Life. Accessed December 17, 2010 at http://www.eol.org/pages/1050051.

Al-Ghzawi, A., S. Zaitoun, H. Shannag. 2009. Incidence and Geographical Distribution of Honeybee (Apis mellifera L.) Pests in Jordan. Ann. soc. entomol. Fr., 45/3: 305-308.

Avery, M., J. Krebs, A. Houston. 1988. Economics of courtship-feeding in the European bee-eater (Merops apiaster). Behavioral Ecology and Sociobiology, 23/2: 61-67.

BirdLife International 2009, 2009. "Merops apiaster" (On-line). In: IUCN 2009. IUCN Red List of Threatened Species.. Accessed January 12, 2010 at http://www.iucnredlist.org/apps/redlist/details/142227/0.

Burton, M., R. Burton. 2002. Bee-eaters. Pp. 180 in B Hoare, T Cooke, eds. International Wildlife Encyclopedia, Vol. 1, Third Edition. Terrytown, New York: Marshall Cavendish.

Casas-Crivlle, A., F. Valera. 2005. The European bee-eater (Merops apiaster) as an ecosystem engineer in arid enviornments. Journal of Arid Enviornments, 60/2: 227-238.

Heneberg, P. 2009. Soil penetrability as a key factor affecting the nesting of burrowing birds. Ecological Research, 24/2: 453-459.

Hoi, H., C. Hoi, J. Kistofik, A. Darolava. 2002. Reproductive success decreases with colony size in the European bee-eater. Ethology Ecology & Evolution, 14: 99-110.

Horváth, G., M. Fischer, T. Szekely. 1992. The delivery of surplus prey to the nest by a pair of bee-eaters (Merops apiaster). Ornis Hung, 2: 11-16.

Kossenko, S., C. Fry. 1998. Competition and coexistence of the European Bee-eater Merops apiaster and the Blue-cheeked Bee-eater Merops periscus in Asia. Ibis, 140/1: 2-13.

Krebs, J., M. Avery. 1985. Central Place Foraging in the European Bee-eater, Merops apiaster. Journal of Animal Ecology, 54/2: 459-472.

Krebs, J., M. Avery. 1984. Chick growth and prey quality in the European Bee-eater (Merops apiaster). Oecologia, 64/3: 363-368.

Lessells, C., M. Avery, J. Krebs. 1994. Nonrandom dispersal of kin: why do European bee-eater (Merops apiaster) brothers nest close together?. Behavior Ecology, 5: 105-113.

Lessells, C., M. Avery. 1989. Hatching Asynchrony in European Bee-eaters Merops apiaster. Journal of Animal Ecology, 58/3: 815-835.

Lessells, C., G. Ovenden. 1989. Heritability of Wing Length and Weight in European Bee-Eaters (Merops apiaster). The Condor, 91/1: 210-214.

Petrescu, A., C. Adam. 2001. Interspecific Relations in the Populations of Merops apiaster L. (Aves: Coraciiformes) of Southern Romania. Travaux du Museum National d' Histoire Naturelle, 43: 305-322.

White, F., G. Bartholomew, J. Kinney. 1978. Physiological and Ecological Correlates of Tunnel Nesting in the European Bee-Eater, Merops apiaster. Physiological Zoology, 51/2: 140-154.

Yosef, R., M. Markovets, L. Mitchell, P. Tryjanowski. 2006. Body condition as a determinant for stopover in bee-eaters (Merops apiaster) on spring migration in the Arava Valley, southern Israel. Journal of Arid Enviornments, 64/3: 401-411.