The term cuckoo bee is used for a variety of different bee lineages which have evolved the kleptoparasitic behaviour of laying their eggs in the nests of other bees, reminiscent of the behavior of cuckoo birds. The name is perhaps best applied to the apid subfamily Nomadinae, but is sometimes used in Europe to mean bumblebees ( Bombus ) in the subgenus Psithyrus. Females of cuckoo bees are easy to recognize in almost all cases, as they lack pollen-collecting structures (the scopa) and do not construct their own nests. They often have reduced body hair, abnormally thick and/or heavily sculptured exoskeleton, and saber-like mandibles, although this is not universally true; other less visible changes are also common.
The number of times kleptoparasitic behavior has independently evolved within the bees is remarkable; C. D. Michener (2000) lists 16 lineages in which parasitism of social species has evolved (mostly in the family Apidae), and 31 lineages that parasitize solitary hosts (mostly in Apidae, Megachilidae, and Halictidae), collectively representing several thousand species, and therefore a very large proportion of overall bee diversity. There are no cuckoo bees in the families Andrenidae, Melittidae, or Stenotritidae, and possibly the Colletidae (there are only unconfirmed suspicions that one group of Hawaiian Hylaeus species may be parasitic).
Cuckoo bees typically enter the nests of pollen-collecting species, and lay their eggs in cells provisioned by the host bee. When the cuckoo bee larva hatches it consumes the host larva's pollen ball, and, if the female kleptoparasite has not already done so, kills and eats the host larva. In a few cases in which the hosts are social species (e.g., the subgenus Psithyrus of the genus Bombus , which are parasitic bumble bees, and infiltrate nests of non-parasitic species of Bombus), the kleptoparasite remains in the host nest and lays many eggs, sometimes even killing the host queen and replacing her - such species are often called social parasites, although a few of them are also what are referred to as "brood parasites."
Many cuckoo bees are closely related to their hosts, and may bear similarities in appearance reflecting this relationship. This common pattern gave rise to the ecological principle known as "Emery's Rule". Others parasitize bees in families different from their own, like Townsendiella , a nomadine apid, one species of which is a kleptoparasite of the melittid genus Hesperapis , whereas the other species in the same genus attack halictid bees.
A bumblebee is any of over 250 species in the genus Bombus, part of Apidae, one of the bee families. This genus is the only extant group in the tribe Bombini, though a few extinct related genera are known from fossils. They are found primarily in higher altitudes or latitudes in the Northern Hemisphere, although they are also found in South America, where a few lowland tropical species have been identified. European bumblebees have also been introduced to New Zealand and Tasmania. Female bumblebees can sting repeatedly, but generally ignore humans and other animals.
Megachilidae is a cosmopolitan family of mostly solitary bees. Characteristic traits of this family are the restriction of their pollen-carrying structure to the ventral surface of the abdomen, and their typically elongated labrum. Megachilid genera are most commonly known as mason bees and leafcutter bees, reflecting the materials from which they build their nest cells ; a few collect plant or animal hairs and fibers, and are called carder bees, while others use plant resins in nest construction and are correspondingly called resin bees. All species feed on nectar and pollen, but a few are kleptoparasites, feeding on pollen collected by other megachilid bees. Parasitic species do not possess scopae. The motion of Megachilidae in the reproductive structures of flowers is energetic and swimming-like; this agitation releases large amounts of pollen.
Kleptoparasitism is a form of feeding in which one animal deliberately takes food from another. The strategy is evolutionarily stable when stealing is less costly than direct feeding, such as when food is scarce or when victims are abundant. Many kleptoparasites are arthropods, especially bees and wasps, but including some true flies, dung beetles, bugs, and spiders. Cuckoo bees are specialized kleptoparasites which lay their eggs either on the pollen masses made by other bees, or on the insect hosts of parasitoid wasps. They are an instance of Emery's rule, which states that insect social parasites tend to be closely related to their hosts. The behavior occurs, too, in vertebrates including birds such as skuas, which persistently chase other seabirds until they disgorge their food, and carnivorous mammals such as spotted hyenas and lions. Other species opportunistically indulge in kleptoparasitism.
Brood parasitism is a subclass of parasitism and phenomenon and behavioural pattern of certain animals, brood parasites, that rely on others to raise their young. The strategy appears among birds, insects and fish. The brood parasite manipulates a host, either of the same or of another species, to raise its young as if it were its own, usually using egg mimicry, with eggs that resemble the host's.
Nomadinae is a subfamily of bees in the family Apidae. They are known commonly as cuckoo bees.
With over 850 species, the genus Nomada is one of the largest genera in the family Apidae, and the largest genus of cuckoo bees. Cuckoo bees are so named because they enter the nests of a host and lay eggs there, stealing resources that the host has already collected. The name "Nomada" is derived from the Greek word nomas, meaning "roaming" or "wandering."
Cuckoo bumblebees are members of the subgenus Psithyrus in the bumblebee genus Bombus. Until recently, the 28 species of Psithyrus were considered to constitute a separate genus. They are a specialized socially parasitic lineage which parasitises the nests of 'true' bumblebees, resulting in the loss of the ability to collect pollen and establish their own nests. Cuckoo bumblebees do not create a worker caste and produce only male and female reproductives. They are considered inquilines in the colonies of 'true' bumblebees.
The early bumblebee or early-nesting bumblebee is a small bumblebee with a wide distribution in most of Europe and parts of Asia. It is very commonly found in the UK and emerges to begin its colony cycle as soon as February which is earlier than most other species, hence its common name. There is even some evidence that the early bumblebee may be able to go through two colony cycles in a year. Like other bumblebees, Bombus pratorum lives in colonies with queen and worker castes. Bombus pratorum queens use aggressive behavior rather than pheromones to maintain dominance over the workers.
Bombus lapidarius is a species of bumblebee in the subgenus Melanobombus. Commonly known as the red-tailed bumblebee, B. lapidarius can be found throughout much of Central Europe. Known for its distinctive black and red body, this social bee is important in pollination.
Bombus hyperboreus is a species of Arctic bumblebee with a circumpolar distribution. The species is primarily found in the arctic areas of Greenland, northern Scandinavia, and Russia. In 2015 the nearctic species, Bombus natvigi, was separated from this species, based on genetic analysis. Accordingly, Bombus hyperboreus is limited to the Palaearctic, despite older literature listing this species as occurring in the Nearctic.
Bombus vestalis, the vestal cuckoo bumblebee, is a species of cuckoo bumblebee that lives in most of Europe, as well as North Africa and western Asia. It is a brood parasite that takes over the nests of other bee species. Its primary host is Bombus terrestris. After its initial classification as Psithyrus vestalis, this bumblebee recently was reclassified into the genus Bombus, subgenus Psithyrus.
Bombus citrinus is a species of bumblebee known commonly as the lemon cuckoo bumblebee due to its lemon-yellow color. It is native to eastern North America.
Bombus sylvestris, known as the forest cuckoo bumblebee or four-coloured cuckoo bee, is a species of cuckoo bumblebee, found in most of Europe and Russia. Its main hosts are Bombus pratorum, Bombus jonellus, and Bombus monticola. As a cuckoo bumblebee, Bombus sylvestris lays its eggs in another bumblebee's nest. This type of bee leaves their young to the workers of another nest for rearing, allowing cuckoo bumblebees to invest minimal energy and resources in their young while still keeping the survival of their young intact.
Bombus bohemicus, also known as the gypsy's cuckoo bumblebee, is a species of socially parasitic cuckoo bumblebee found in most of Europe with the exception of the southern Iberian Peninsula and Iceland. B. bohemicus practices inquilinism, or brood parasitism, of other bumblebee species. B. bohemicus is a generalist parasite, successfully invading several species from genus Bombus. The invading queen mimics the host nest's chemical signals, allowing her to assume a reproductively dominant role as well as manipulation of host worker fertility and behavior.
Bombus suckleyi is a species of bumblebee known commonly as Suckley's cuckoo bumblebee, named after biologist George Suckley. Suckley's bumble bee is a generalist pollinator and represents a rare group of obligate, parasitic bumble bees. Suckley's bumble bee is a social-parasite because it invades the nests of the host bumble bees, including the western bumble bee, and relies on host species workers to provision its larvae. It is native to northwestern North America, including Alaska and parts of western and central Canada and the western United States.
Bombus fervidus, the golden northern bumble bee or yellow bumblebee, is a species of bumblebee native to North America. It has a yellow-colored abdomen and thorax. Its range includes the North American continent, excluding much of the southern United States, Alaska, and the northern parts of Canada. It is common in cities and farmland, with populations concentrated in the Northeastern part of the United States. It is similar in color and range to its sibling species, Bombus californicus, though sometimes also confused with the American bumblebee or black and gold bumblebee. It has complex behavioral traits, which includes a coordinated nest defense to ward off predators. B. fervidus is an important pollinator, so recent population decline is a particular concern.
The Rhathymini are a tribe of kleptoparasitic apid bees.
Exomalopsis is a genus of bees in the family Apidae. They occur in the Western Hemisphere.
Exaerete smaragdina is a species of kleptoparasitic euglossine bees.
Bombus inexspectatus is an endangered species of bumblebee native to Europe.