The California carpenter bee, ''Xylocopa californica'', is a species of

carpenter bee Carpenter bees are species in the genus ''Xylocopa'' of the subfamily Xylocopinae. The genus includes some 500 bees in 31 subgenera. The common name "carpenter bee" derives from their nesting behavior; nearly all species burrow into hard plant m ...

in the order Hymenoptera, and it is native to western North America.

Distribution

There are approximately 400 species worldwide of the genus ''Xylocopa.''LeBuhn, G., & Pugh N. B. 2013. Field Guide to the Common Bees of California: Including Bees of the Western United States. University of California Press. 107(1): 98-99. ''X. californica'' is typically found in

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the m ...

Nevada Nevada ( ; ) is a state in the Western region of the United States. It is bordered by Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the 7th-most extensive, ...

Oregon Oregon () is a state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington, while the Snake River delineates much of its eastern boundary with Idaho. T ...

, Washington,

Utah Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to it ...

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ke ...

Texas Texas (, ; Spanish: ''Texas'', ''Tejas'') is a state in the South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2020, it is the second-largest U.S. state by ...

, and Northwestern

Mexico Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...

, with outlying records in

Montana Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columb ...

Kansas Kansas () is a state in the Midwestern United States. Its capital is Topeka, and its largest city is Wichita. Kansas is a landlocked state bordered by Nebraska to the north; Missouri to the east; Oklahoma to the south; and Colorado to the ...

, and

Louisiana Louisiana , group=pronunciation (French: ''La Louisiane'') is a state in the Deep South and South Central regions of the United States. It is the 20th-smallest by area and the 25th most populous of the 50 U.S. states. Louisiana is borde ...

. It is especially abundant, along with '' X. sonorina'', in the Central Valley and in

Southern California Southern California (commonly shortened to SoCal) is a geographic and Cultural area, cultural region that generally comprises the southern portion of the U.S. state of California. It includes the Los Angeles metropolitan area, the second most po ...

, including the

Mojave Desert The Mojave Desert ( ; mov, Hayikwiir Mat'aar; es, Desierto de Mojave) is a desert in the rain shadow of the Sierra Nevada mountains in the Southwestern United States. It is named for the indigenous Mojave people. It is located primarily ...

. They are agriculturally

beneficial insect Beneficial insects (sometimes called beneficial bugs) are any of a number of species of insects that perform valued services like pollination and pest control. The concept of ''beneficial'' is subjective and only arises in light of desired outcome ...

s and pollinators of diverse California chaparral and woodlands and desert

native plant In biogeography, a native species is indigenous to a given region or ecosystem if its presence in that region is the result of only local natural evolution (though often popularised as "with no human intervention") during history. The term is equ ...

species. This carpenter bee is active during hot seasons. Therefore, they are considered an endothermic insect as it absorbs heat in the desert conditions. As the bee absorbs too much heat in its body, it has to limit the time it flies and fly in the time of day in which it is cooler.

Description

Their head is larger and thicker than their thorax; however, the size of the head differs between females and males. Female carpenter bees have bigger heads than males with more narrow heads. The California carpenter bee is all black, with bluish/greenish reflections. The males typically have at least a few light hairs on the

pronotum The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum ( dorsal), the prosternum (ventral), and the propleuron (lateral) on e ...

(dorsal

prothorax The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites (exoskeletal plates) are the pronotum ( dorsal), the prosternum ( ventral), and the propleuron ( lateral) o ...

) and the abdominal segments. California carpenter bees have hair on their heads; most of their hair lays in the lower part of their head and cheeks compared to the sparse hairs on the top of the head. The female carpenter bees' hair is black, while the male carpenter bees' hair is yellow and yellowish colors. They have dark wings without stigma and are 13–30 mm long overall.

Foraging Behavior

''X. californica'' has been observed to rob nectar from desert shrubs, ''Fouquieria splendens'''','' and are determined to be their primary pollinator in the Big Bend National Park, Texas, USA. They rob the nectar from flowers by chewing a hole on the side of the flower and taking the nectar without participating in pollination. They like both nectar and pollen, except the pollen sources seem more specific; they prefer the pollen from the plants ''

Larrea tridentata ''Larrea tridentata'', called creosote bush and greasewood as a plant, chaparral as a medicinal herb, and ''gobernadora'' (Spanish for "governess") in Mexico, due to its ability to secure more water by inhibiting the growth of nearby plants. In S ...

'' and ''Prosopis glandulosa''''.''Smith, W.E., and Whitford, W.G. 1978. Factors Affecting the Nesting Success of the Large Carpenter Bee, ''Xylocopa californica arizonensis '. ''Environmental Entomology''.'' 7:614-616. They tend to visit larger open flowers due to their large size. The foraging behavior consists of three movements- fast forward flight, hovering and perching or walking on the flower blossoms Chappell, M.A. 1982. Temperature Regulation of Carpenter Bees (''Xylocopa californica'') Foraging in the Colorado Desert of Southern California. Physiological Zoology. 55: 267-280. File:Fouquieria splendens flowers 2.jpg, ''

Fouquieria splendens ''Fouquieria splendens'' (commonly known as ocotillo (), but also referred to as buggywhip, coachwhip, candlewood, slimwood, desert coral, Jacob's staff, Jacob cactus, and vine cactus) is a plant indigenous to the Sonoran Desert and Chihuahua ...

'' File:Larrea tridentata - Flickr - aspidoscelis.jpg, ''

'' File:Prosopis glandulosa kz4.jpg, ''

Prosopis glandulosa ''Prosopis glandulosa'', commonly known as honey mesquite, is a species of small to medium-sized, thorny shrub or tree in the legume family (Fabaceae). Distribution The plant is primarily native to the Southwestern United States and Northern M ...

Floral Sonication

Floral sonication is essential for the foraging of many Hymenoptera.Jankkauski, M., C. Casey., C. Heveran., M.K. Busby., S. Buchmann. 2022. Carpenter Bee Thorax Vibration and Force Generation Inform Pollen Release Mechanisms During Floral Buzzing. Scientific Reports. 12654. ''X. californica'' performs floral sonication to obtain

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametophyt ...

.King, M.J., and S.L., Buchmann. 2003. Floral Sonication by Bees: Mesosomal Vibration by ''Bombus'' and ''Xylocopa'', but not ''Apis'' (Hymenoptera: ''Apidae''), Ejects Pollen from Poricidal Anthers. Journal of the Kansas Entomological Society. 76: 295-305. They do this by gripping the poricidal

anthers The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filam ...

with their mandibles and contracting their flight muscles, rapidly vibrating their body and the flower's anthers, releasing the pollen onto the abdomen and legs of the bees. This process allows for

pollination Pollination is the transfer of pollen from an anther of a plant to the stigma of a plant, later enabling fertilisation and the production of seeds, most often by an animal or by wind. Pollinating agents can be animals such as insects, birds ...

to happen. The vibration

frequency Frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as ''temporal frequency'' for clarity, and is distinct from ''angular frequency''. Frequency is measured in hertz (Hz) which is eq ...

is different throughout their body; their head's natural vibration is 87 Hz, and their abdominal terga is 163 Hz.''X. californica'' can adjust its frequency to different types of flowers.

Temperature Regulation

''X. californica'' inhabit the deserts of southwestern North America and endure high temperatures while they

forage Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used m ...

. Foraging in these high temperatures may cause

thermoregulatory Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different. A thermoconforming organism, by contrast, simply adopts the surrounding temperature ...

problems for the bee, which is increased by the heat released from the muscular activity needed for their flight. Unlike other insects, they can fly in temperatures as high as 48°C, which would be deadly for others, but can fly for a short period of time. On the other hand, they can not withstand temperatures lower than 10-15 °C.

Reproduction

Mating Behavior

''X. californica'' has many types of mating behaviors.Alock, John. 1991. Mate-Locating Behavior of ''Xylocopa californica'' ''arizonensis'' Cresson (Hymenoptera: ''Anthophoridae)''. Journal of the Kansas Entomological Society. 64: 349-356 These include hovering near sites and chasing away other males, exhibiting female-defense

polygyny Polygyny (; from Neoclassical Greek πολυγυνία (); ) is the most common and accepted form of polygamy around the world, entailing the marriage of a man with several women. Incidence Polygyny is more widespread in Africa than in any o ...

. Multiple males may try to grasp the female when she returns to the nest, then a struggle between the males may happen to be able to grasp the female midair to

copulate Sexual intercourse (or coitus or copulation) is a sexual activity typically involving the insertion and thrusting of the penis into the vagina for sexual pleasure or reproduction.Sexual intercourse most commonly means penile–vaginal penetr ...

; in particular, they look for virgin females because females only mate once in their lifetime.Hurd Jr., P.D. 1958. Observations on the Nesting Habits of Some New World Carpenter Bees with Remarks on their Importance in the Problem of Species Formation (Hymenoptera: ''Apoidea''). Annals Entomological Society of America. 51: 365- 375 After a few seconds, they separate, and the male returns to its hovering area. Other males may patrol more than one nest and shuttle throughout many sites in a day. If they are not patrolling the nests, then they may exhibit

scramble competition In ecology, scramble competition (or complete symmetric competition or exploitation competition) refers to a situation in which a resource is accessible to all competitors (that is, it is not monopolizable by an individual or group). However, sin ...

at flowering sites, where they hope to catch a female. The males are territorial, but they do not have a stinger.

Nesting

''X. californica'' carve their nest in wood. They dig into the wood using their sharp

mandibles In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...

while they vibrate their body- they do not eat the wood. They dig a tunnel in substrates such as live or dead wood and hollow stems of the

Yucca ''Yucca'' is a genus of perennial plant, perennial shrubs and trees in the family (biology), family Asparagaceae, subfamily Agavoideae. Its 40–50 species are notable for their Rosette (botany), rosettes of evergreen, tough, sword-shaped Leaf, ...

and

Agave ''Agave'' (; ; ) is a genus of monocots native to the hot and arid regions of the Americas and the Caribbean, although some ''Agave'' species are also native to tropical areas of North America, such as Mexico. The genus is primarily known for ...

plants, then dig to the right and left, creating a T-shape nest. Their nest's success depends on the available pollen and nectar found in the area. A suitable nest substrate is needed for their reproduction and survival; the quantity of stalks in the area is important in determining their total nest density.

Predators

''X. californica'' does not have many predators, but in the southwest of Northern America, the ladder-backed woodpecker, ''Dendrocopos scalaria,'' has been observed to attack their nests. And the bee fly, ''Anthrax simson,'' is a parasite of their nests There are reports of the honey bee, ''Apis mellifera'''','' having negative effects on ''X. californica'' populations. The carpenter bees are attracted to the floral scents of the honey produced by the honey bees; ''X. californica'' may come near or inside their hives and get attacked by the hive resulting in the death of the carpenter bee.Thoenes, S.C. 1993. Fatal Attraction of Certain Large-Bodied Native Bees to Honey Bee Colonies. Journal of the Kansas Entomological Society. 66: 210-213.

Disease

The fungus ''Ascosphaera apis'''','' is generally found in the larva of the European honey bee, ''Apis mellifera'''','' causing the

larva A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. ...

to be mummified''.''Gilium, M., B. J. Lorenz., S. L., Buchmann. 1994. Ascosphaera apis, the Chalkbrood Pathogen of the Honey Bee, ''Apis mellifera'', from Larvae of a Carpenter Bee, ''Xylocopa californica arizonensis''. Journal of Invertebrate Pathology. 63: 307-309. It has also been found in ''X. californica,'' except the infected larva does not look the same as the honey bee's; they develop spore cysts beneath the larval

integument In biology, an integument is the tissue surrounding an organism's body or an organ within, such as skin, a husk, shell, germ or rind. Etymology The term is derived from ''integumentum'', which is Latin for "a covering". In a transferred, or ...

. ''X. californica'' are not the natural hosts of this fungus, but they may be infected if they visit the same plants as other infected honey bees.

Subspecies

The species has three named subspecies, defined solely by coloration and geography: *''X. c. arizonensis'' Cresson, 1879 *''X. c. californica'' Cresson, 1864 *''X. c. diamesa'' Hurd, 1954

Gallery

File:Female California carpenter bee 2.jpg, Female ''Xylocopa californica'' File:Western Carpenter Bee (Apidae, Xylocopa californica) (28384081021).jpg, ''Xylocopa californica'' File:California carpenter bee (26104660770).jpg, ''Xylocopa californica'' File:Western Carpenter Bee (Apidae, Xylocopa californica) (28179490850).jpg, ''Xylocopa californica'' File:Xylocopa californica.jpg, ''Xylocopa californica''

References

External links

Discoverlife.org: Photo gallery of ''Xylocopa californica'' (Western Carpenter Bee)
— ''with list of host plants''.
BugGuide.Net: ''Xylocopa californica'' — Western Carpenter Bee
— ''images''. {{Taxonbar, from=Q2767792 Hymenoptera of North America Insects of Mexico Insects of the United States Fauna of California Fauna of the Southwestern United States Fauna of the California chaparral and woodlands Fauna of the Great Basin Fauna of the Mojave Desert Natural history of the Central Valley (California) Xylocopinae Insects described in 1864 Taxa named by Ezra Townsend Cresson