Merops orientalisgreen bee-eater

Geographic Range

The green bee-eater has a wide range in the eastern hemisphere. The green bee-eater is a resident in west and northeast Africa, in arid areas. From Africa, its range extends through the Middle East, Egypt and Israel, and Iran. Green bee-eaters are also common throughout India and southwest China. In addition, the green bee-eater’s range extends into Southeast Asia in countries such as Thailand and Cambodia. Green bee-eaters do not migrate, but they can have seasonal movements depending on rainfall and food availability. (Clements, 1981; Mohamed Ali and Abdou Taha, 2012; Robson, 2000)

Habitat

The green bee-eater is found in a variety of habitats throughout its range, from sea level to 1600 meters in elevation. Its preferred habitat consists of an arid environment, especially in its range in Africa. Green bee-eaters prefer to inhabit open areas with bushes or trees for perching. Specific habitats that green bee-eaters can be found in include habitats like arid woodlands and dry riverbeds. The green bee-eater creates tunnels in sandy banks for its nests, so it needs a sandy environment to breed. However, the green bee-eater can also inhabit areas where there is some human activity. Especially in the more eastern edge of their range, they can be found in the thickets around crop fields and in the open pastures or farmland. However, they cannot be found in places with high levels of human activity. Overall, the green bee-eater tends to be a fairly tame bird, and is commonly seen throughout its range. (Mishra, 2019; Robson, 2000; Wasnik, et al., 2014)

  • Range elevation
    1600 (high) m
    5249.34 (high) ft

Physical Description

The green bee-eater is a smaller bird with brilliant plumage all year round. The majority of its body is a vivid emerald green color, with the most green being on its belly. There is some variation in appearance in the 8 subspecies of the green bee-eater. The cap of the bird can vary in color, depending on the subspecies, from green to gold or reddish brown. Some subspecies' green wings have a gold red-brown tint to them. The throat of the subspecies of the green bee-eater can also vary, with subspecies in the Arabian Peninsula having a blue throat, subspecies in North Africa and Southeast Asia having a green throat, subspecies in Sudan having a yellow throat, and subspecies in India having a pale blue throat. All green bee-eaters have a distinct feature called a "gorget," which is a black stripe around the throat of the bird. These birds also have a distinct black stripe that runs along the side of their face through their crimson colored eye. Green bee-eaters have two distinct central tail streamers, black in color, that extend about 6 cm. Their beak, long and curved slightly downwards, is adapted for catching insects.

There is some sexual dimorphism in green bee-eaters. Male birds tend to have brighter plumage overall. The juvenile birds lack the black tail streamers and gorget. Juveniles are duller in color and their throat and cheeks are buffy colored and the rest of their body is a duller green. (Mishra, 2019; Robson, 2000; Wasnik, et al., 2014)

  • Sexual Dimorphism
  • male more colorful
  • Range mass
    15 to 20 g
    0.53 to 0.70 oz
  • Range length
    16 to 18 cm
    6.30 to 7.09 in
  • Range wingspan
    8.9 to 9.7 cm
    3.50 to 3.82 in

Reproduction

The green bee-eater is a monogamous bird. They have one brood per year during their breeding season, which is from March until June. The green bee-eater nests in colonies of about 10-15 other pairs of birds, and recruit helpers to assist with foraging for food and protection of the eggs and nestlings. No courtship displays have been recorded for the green bee-eater. (Mishra, 2019; Wasnik, et al., 2014)

The green bee-eater produces one brood per year during its breeding season, which starts in March and ends in June. The green bee-eater first excavates a tunnel where they will lay their eggs. They excavate the tunnel most often in the side of riverbanks, and sometimes on the ground, in places that have loose sandy soil that are easy to excavate. The green bee-eater makes their nest cavities in colonies of about 10-15 other pairs. The mean diameter of the entrance hole of the tunnel that the green bee-eater excavates for their nest is 8.9 cm. The mean length of the tunnel from the entrance to the nesting cavity is 105 cm.

After excavating the tunnel, the green bee-eater lays its eggs and incubates them. The average clutch size of the green bee-eater is 4 eggs, but 3 eggs is also a common clutch size. Clutches of 5 and 6 eggs are less common. Their eggs are white, small, and sphere-shaped. The eggs usually weigh about 2-5 grams, and the average dimensions of the eggs are 20.91-21.09 mm in length by 13.89-14.11 mm in width. Both parents incubate the eggs. The incubation period of the green bee-eater typically lasts 14-16 days, and then the eggs hatch.

The green bee-eater lays its eggs asynchronously, meaning not at the same time. The eggs also hatch asynchronously, usually over the course of one or a few days, in the order that the eggs were laid. This allows the stronger nestlings to receive more food and resources, so the weaker nestlings may die. When they hatch, the nestlings are naked and pink. They weigh an average of 3.16 grams when they hatch. The nestlings fledge after about 20-25 days and the average weight at that time is 20.75 grams. About 25 days after hatching, the nestlings have developed their feathers and resemble adult birds. (Asokan, 1995; Asokan, et al., 2010; Mishra, 2019)

  • Breeding interval
    One brood per year
  • Breeding season
    March-June
  • Range eggs per season
    2 to 6
  • Range time to hatching
    14 to 16 days
  • Range fledging age
    20 to 25 days

The green bee-eater has high parental investment in its offspring. Before laying the eggs, the male and female help excavate the tunnel and nest cavity, usually in the bank of a dry riverbed. They excavate the cavity at a sloped angle so it is not possible to see the nesting area from the outside, as a defense against predators. The tunnel to the nest cavity is long, with the mean length being 105 cm. During incubation, both the male and female take turns sitting on the eggs, splitting the time about equally. The other will sit outside the nest cavity and watch for predators. When guarding their nest cavity, the green bee-eater will usually sit in vegetation close the nest and watch for predators, and will dive at perceived predators.

The green bee-eater is a cooperative breeder. Before egg laying is finished, the male green bee-eater will choose “helpers” for their nest, which are other individual green bee-eaters. The helpers' main job is to bring food for the nestlings, but they also help defend the nest against predators. In addition to the helpers, after the eggs hatch, both the male and female bee-eaters provide food for their young. (Asokan, et al., 2010; Burt, 2002)

Lifespan/Longevity

There has been no studies about lifespan in green bee-eaters.

Behavior

Green bee-eaters are sociable birds and are often seen in groups. Because they are monogamous, green bee-eaters will often be seen in pairs with their mate as well as in a larger group. The green bee-eater breeds in colonies with 10-15 other pairs of birds to help with protection of their young.

Green bee-eaters spend about half their time perching and scanning during the day. They are a sit-and-wait predator, so they will often perch on cables, shrubs, or trees, scanning for insect prey. Green bee-eaters’ main feeding times are in the morning and in the evening, which is similar to most birds. In the morning, green bee-eaters can often be seen taking dust baths in groups to keep their plumage in good condition. They also preen themselves during the day, and take time to rest when the day reaches its hottest point. They rest in dense trees and shrubs. Green bee-eaters can often be seen perching on branches very close to each other in large groups. (Ali and Asokan, 2015; Burt, 2002; Mishra, 2019; Wasnik, et al., 2014)

Home Range

Territory sizes and defense has not been studied for green bee-eaters. However, the white fronted bee-eater (Merops bullockoides), a colonial breeder like the green bee-eater, defends foraging territories together as a clan. The size of the territory depends on the size of the clan. Green bee-eaters do defend their nests from predators. They will dive at potential predators, such as lizards. The green bee-eater lives in harmony with many other bird species throughout its range such as the common myna (Acridotheres tristis), rock pigeon (Columba livia), spotted dove (Spilopelia chinensis), and rose ringed parakeet (Psittacula krameria). (Burt, 2002; Hegner and Emlen, 1987; Mishra, 2019)

Communication and Perception

The green bee-eater, a sit-and-wait predator, uses its vision while sitting to scan and look for prey. Like most birds, green bee-eaters have four opsins in their retina, and they use mainly vision to hunt and protect their nests. One important thing that green bee-eaters use their vision for is to perceive where a predator is looking. If a green bee-eater sees that a predator is able to see their nest, they will not enter their own nest. This evidence suggests that green bee-eaters have theory of mind, which means that they can perceive that organisms' mental states can be different from their own. Green bee-eaters use this and their vision to determine if a predator could be a threat to their nest or not.

The green bee-eater gives short alarm calls that are sharp and sound like "tic" or "ti-ti-ti" to communicate with other members of their species. They also have a second call, which is a soft trill that sounds like "trree-trree-trree-trree-trree." Green bee-eaters only vocalizations are these two calls, which they use to alert other members of their species to their location and alert them if there is a predator. Green bee-eaters do not have a song that they use to attract mates. In addition, there has been no research that suggests that green bee-eaters perform displays. To attract mates and assist pair bonding, green bee-eaters will participate in courtship feeding. (Ali and Asokan, 2015; Asokan, 1995; Burt, 2002; Robson, 2000; Smitha, et al., 1999; Wasnik, et al., 2014; Watve, et al., 2002)

Food Habits

The green bee-eater is an insectivore. They will perch on branches or wires and scan the environment for insects. They eat mainly flying insects such as bees (Hymenoptera), grasshoppers (Orthoptera), beetles (Coleoptera), butterflies (Lepidoptera), dragonflies (Odonata), flies (Diptera) and other insects (Hemiptera). Of these insects, bees and beetles have been found to be the major part of the green bee-eater’s diet. The green bee-eater is adapted to catching insects while they are flying. When an insect is flying, the green bee-eater will chase after it by flying close to the ground and change direction quickly in order to capture the insect. As their name indicates, they are very efficient at catching and eating wild bees. After catching a bee, the green bee-eater will fly back to a perch, and then hit and rub the bee against the perch several time in order to get rid of the poisonous stinger. The green bee-eater then swallows its prey whole. (Ali and Asokan, 2015; Asokan, et al., 2009; Mishra, 2019)

  • Animal Foods
  • insects

Predation

Green bee-eaters have a unique way to avoid predators when they are breeding, because their main predators prey on nests and nestlings. Studies have suggested that green bee-eaters have theory of mind, which means that they can perceive that other organisms' mental states are different from their own. When a predator's gaze is looking towards the green bee-eater's nest, the bird will not enter the tunnel leading to the nest. Instead, it will wait until the predator has looked away from the tunnel to enter the nest. The green bee-eater does this to prevent predators from finding their eggs. In addition, green bee-eaters will dive at predators when they are nesting to try to warn them away. Some predators that have been documented as preying on green bee-eater nests include dogs (Canis lupus familiaris) and the butterfly lizard (Leiolepis belliana). Snakes and other reptiles have been recorded to prey on other bee-eater species’ nests. Because of their bright coloration, birds of prey and raptors are predators of the adult bee-eaters. (Burt, 2002; Smitha, et al., 1999; Wasnik, et al., 2014; Watve, et al., 2002; Yuan, et al., 2006)

Ecosystem Roles

The green bee-eater is a predator of many insect species. They can help control insect populations throughout their range. On the other hand, some animals, such as lizards, may prey on the eggs and nestlings of the green bee-eater.

There has not been much other research on the ecosystem roles of the green bee-eater. Research has been done on parasites of the European bee-eater (Merops apiaster) and blue-cheeked bee-eater (Merops superciliosus persicus), both that are found in Iraq, which is part of the green bee-eater's range as well. It was found that Haemoproteus lairdi, H. manwelli, H. meropis, and H. hudaidensis were blood parasites that use the European bee-eater and the blue-cheeked bee-eater as a host. These parasites may also use the green bee-eater as a host, but there needs to be more research done on the blood parasites of the green bee-eater to confirm this. (Mishra, 2019; Mohammad and AlNeaimi, 2009)

Economic Importance for Humans: Positive

Because the green bee-eater is an insectivore, they are a benefit to crop agriculture. Birds, such as the green bee-eater, can be effective insect bio-controls for farmers because they are cost-effective, and can gather in large groups to catch and control insect pest populations. Specifically, green bee-eaters are known to be bio-controls against a bug called the white grub (Holotricha sp.), which can infect and destroy the roots of human crops. Many farmers have been known to encourage insectivorous birds like the green bee-eater to come to their agriculture fields by doing things such as setting up perches that the birds can use.

Besides helping human agriculture, the green bee-eater is has brilliant plumage and is a beautiful bird and is exciting for any person to see. Bird watching is an important part of ecotourism in places like India, and green bee-eaters can be found in natural areas that are important for ecotourism. In addition, green bee-eaters are an interesting species to perform studies on, because of different traits they have such as theory of mind, colonial and cooperative breeding, and adaptations to catch bees and insects. However, there has not been much extensive research done on the green bee-eater, so more studies need to be done on the them to discover more about them. (Asokan, et al., 2009; Mishra, 2019; Mohanta and Behera, 2014; Wasnik, et al., 2014)

  • Positive Impacts
  • ecotourism
  • research and education
  • controls pest population

Economic Importance for Humans: Negative

Green bee-eaters have some negative effects on humans — bee-keepers in particular. Because the green bee-eater preys on bees, they can negatively affect bee populations that are maintained by bee-keepers. Studies have found that the green bee-eater preys on honeybees, and that they have higher prey capture efficiency close to an apiary, the place where bee-keepers keep beehives. Bee-eaters' predation on bees can create significant losses to a bee-keeper's honeybee population. In addition, the green bee-eater was found to kill a significant number of virgin queen bees, reducing the amount of matings that the queen bees can have, which negatively affects a hive’s population. The way that the green bee-eater affects honeybee populations could be an important issue for its conservation. (Mohamed Ali and Abdou Taha, 2012; Wasnik, et al., 2014)

  • Negative Impacts
  • crop pest

Conservation Status

The green bee-eater is considered "Least Concern" by the IUCN Red List. It is known to be a common bird throughout it range. However, in the future, there could be some threats that affect its population. Bee numbers are declining around the world, and because they are one of the principal foods of the green bee-eater, this could negatively affect their population. In addition, because beekeepers regard the green bee-eater as a pest, there could be some controversy of their conservation in the future. ("The IUCN Red List of Threatened Species", 2020; Wasnik, et al., 2014)

Contributors

Megan Quinn (author), Northern Michigan University, Alec Lindsay (editor), Northern Michigan University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

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

chaparral

Found in coastal areas between 30 and 40 degrees latitude, in areas with a Mediterranean climate. Vegetation is dominated by stands of dense, spiny shrubs with tough (hard or waxy) evergreen leaves. May be maintained by periodic fire. In South America it includes the scrub ecotone between forest and paramo.

chemical

uses smells or other chemicals to communicate

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.
ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

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

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

oviparous

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

scrub forest

scrub forests develop in areas that experience dry seasons.

sexual

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

social

associates with others of its species; forms social groups.

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

terrestrial

Living on the ground.

visual

uses sight to communicate

References

2020. "The IUCN Red List of Threatened Species" (On-line). Accessed April 14, 2020 at https://www.iucnredlist.org.

Ali, A., S. Asokan. 2015. Diurnal-activity Patterns of the Small Bee-eater (Merops orientalis) in Southern India. Tropical Life Sciences Research, 26: 9-20.

Asokan, S. 1995. Ecology of the small green bee-eater (Merops orientalis) latham 1801 with special reference to its population feeding and breeding in Mayiladuthurai Tamil Nadu South India. Tiruchirappalli: Bharathidasan University.

Asokan, S., A. Ali, R. Manikannan. 2010. Breeding biology of the Small Bee-eater Merops orientalis (Latham, 1801) in Nagapattinam District, Tamil Nadu, India. Journal of Threatened Taxa, 2: 797-804.

Asokan, S., A. Ali, R. Manikannan. 2009. Diet of three insectivorous birds in Nagapattinam District, Tamil Nadu, India - a preliminary study. Journal of Threatened Taxa, 6: 327-330.

Burt, D. 2002. Social and breeding biology of bee-eaters in Thailand. The Wilson Bulletin, 114: 275-279.

Clements, J. 1981. Birds of the World: A Checklist. New York: Facts on File, Inc..

Hegner, R., S. Emlen. 1987. Territorial Organization of the White Fronted Bee‐eater in Kenya. Ethology, 76: 189-222.

Mishra, S. 2019. The Ecology of Merops Orientalis. International Journal of Scientific Research in Biological Sciences, 6: 12-14.

Mohamed Ali, M., E. Abdou Taha. 2012. Bee-Eating Birds (Coraciiformes: Meropidae) Reduce Virgin Honey Bee Queen Survival during Mating Flights and Foraging Activity of Honey Bees (Apis mellifera L.). International Journal of Scientific & Engineering Research, 3: 1-5.

Mohammad, M., T. AlNeaimi. 2009. Blood parasites of two bee-eaters in Iraq. Bulletin of the Iraq Natural History Museum, 9: 71-77.

Mohanta, R., S. Behera. 2014. An Annotated Preliminary Checklist of Birds Diversity in Coastal Ecotourism Area of Ganjam, Southern Odisha, India. Open Journal of Ocean and Coastal Sciences, 1: 1-7.

Robson, C. 2000. A Guide to the Birds of Southeast Asia. United Kingdom: New Holland Publishers (UK) Ltd.

Smitha, B., J. Thakar, M. Watve. 1999. Do bee eaters have theory of mind?. Current Science, 76: 574-577.

Wasnik, S., P. Telkhade, R. Tijare, P. Charde. 2014. Ecology of the Little Green Bee-eater (Merops orientalis) from Nagpur Area (India). International Journal of Researches in Biosciences and Agriculture Technology, 2: 808-815.

Watve, M., J. Thakar, A. Kale, S. Puntambekar, I. Shaikh, K. Vaze, M. Jog, S. Paranjape. 2002. Bee-eaters ( Merops orientalis ) respond to what a predator can see. Animal Cognition, 5: 253-259.

Yuan, H., D. Burt, L. Wang, W. Chang, M. Wang. 2006. Colony site choice of blue-tailed bee-eaters: influences of soil, vegetation, and water quality. Journal of Natural History, 40: 485-493.