page_title: Bee
section_title: Solitary and communal bees
hierarchical_section_title: Bee / Sociality / Solitary and communal bees
caption_attribution_description: English: Osmia cornifrons at nest's entrance. Willow Grove, Montgomery County, Pennsylvania, USA. https://bugguide.net/node/view/181600/bgimage
context_page_description: Bees are flying insects closely related to wasps and ants, known for their role in pollination and, in the case of the best-known bee species, the western honey bee, for producing honey. Bees are a monophyletic lineage within the superfamily Apoidea. They are presently considered a clade, called Anthophila. There are over 16,000 known species of bees in seven recognized biological families. Some species — including honey bees, bumblebees, and stingless bees — live socially in colonies while some species — including mason bees, carpenter bees, leafcutter bees, and sweat bees — are solitary.
  Bees are found on every continent except for Antarctica, in every habitat on the planet that contains insect-pollinated flowering plants. The most common bees in the Northern Hemisphere are the Halictidae, or sweat bees, but they are small and often mistaken for wasps or flies. Bees range in size from tiny stingless bee species, whose workers are less than 2 millimetres long, to Megachile pluto, the largest species of leafcutter bee, whose females can attain a length of 39 millimetres.
context_section_description: Most other bees, including familiar insects such as carpenter bees, leafcutter bees and mason bees are solitary in the sense that every female is fertile, and typically inhabits a nest she constructs herself. There is no division of labor so these nests lack queens and worker bees for these species. Solitary bees typically produce neither honey nor beeswax. 
  Bees collect pollen to feed their young, and have the necessary adaptations to do this. However, certain wasp species such as pollen wasps have similar behaviours, and a few species of bee scavenge from carcases to feed their offspring. Solitary bees are important pollinators; they gather pollen to provision their nests with food for their brood. Often it is mixed with nectar to form a paste-like consistency. Some solitary bees have advanced types of pollen-carrying structures on their bodies. Very few species of solitary bee are being cultured for commercial pollination. Most of these species belong to a distinct set of genera which are commonly known by their nesting behavior or preferences, namely: carpenter bees, sweat bees, mason bees, plasterer bees, squash bees, dwarf carpenter bees, leafcutter bees, alkali bees and digger bees.
  Most solitary bees nest in the ground in a variety of soil textures and conditions while others create nests in hollow reeds or twigs, holes in wood. The female typically creates a compartment (a "cell") with an egg and some provisions for the resulting larva, then seals it off. A nest may consist of numerous cells. When the nest is in wood, usually the last (those closer to the entrance) contain eggs that will become males. The adult does not provide care for the brood once the egg is laid, and usually dies after making one or more nests. The males typically emerge first and are ready for mating when the females emerge. Solitary bees are either stingless or very unlikely to sting (only in self-defense, if ever).
  While solitary, females each make individual nests. Some species, such as the European mason bee Hoplitis anthocopoides, and the Dawson's Burrowing bee, Amegilla dawsoni, are gregarious, preferring to make nests near others of the same species, and giving the appearance of being social. Large groups of solitary bee nests are called aggregations, to distinguish them from colonies. In some species, multiple females share a common nest, but each makes and provisions her own cells independently. This type of group is called "communal" and is not uncommon. The primary advantage appears to be that a nest entrance is easier to defend from predators and parasites when there are multiple females using that same entrance on a regular basis.
caption: The mason bee Osmia cornifrons nests in a hole in dead wood. Bee "hotels" are often sold for this purpose.
exif: {"Image Make": "Canon", "Image Model": "Canon PowerShot S3 IS", "Image Orientation": "Horizontal (normal)", "Image XResolution": "180", "Image YResolution": "180", "Image ResolutionUnit": "Pixels/Inch", "Image DateTime": "2008:05:01 13:04:59", "Image YCbCrPositioning": "Centered", "Image ExifOffset": "2258", "Image Padding": "[]", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "180", "Thumbnail YResolution": "180", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "7080", "Thumbnail JPEGInterchangeFormatLength": "4848", "EXIF ExposureTime": "1/80", "EXIF FNumber": "8", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "2008:05:01 13:04:59", "EXIF DateTimeDigitized": "2008:05:01 13:04:59", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "3", "EXIF ShutterSpeedValue": "101/16", "EXIF ApertureValue": "6", "EXIF ExposureBiasValue": "1/3", "EXIF MaxApertureValue": "29/8", "EXIF MeteringMode": "CenterWeightedAverage", "EXIF Flash": "Flash did not fire, compulsory flash mode", "EXIF FocalLength": "208/5", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "2816", "EXIF ExifImageLength": "2112", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "Interoperability RelatedImageWidth": "2816", "Interoperability RelatedImageLength": "2112", "EXIF InteroperabilityOffset": "6918", "EXIF FocalPlaneXResolution": "112640/9", "EXIF FocalPlaneYResolution": "2112000/169", "EXIF FocalPlaneResolutionUnit": "2", "EXIF SensingMethod": "One-chip color area", "EXIF FileSource": "Digital Camera", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Manual Exposure", "EXIF WhiteBalance": "Manual", "EXIF DigitalZoomRatio": "1", "EXIF SceneCaptureType": "Standard", "EXIF Padding": "[]", "EXIF OffsetSchema": "4146"}