California carpenter bee

{{Short description|Species of bee}} {{Speciesbox | image = Xylocopa_californica.jpg | image_caption = Female | genus = Xylocopa | species = californica | authority = Cresson, 1864 }}

The '''California carpenter bee''' or '''Western carpenter bee''', '''''Xylocopa californica''''', is a species of carpenter bee in the order Hymenoptera, and it is native to western North America.<ref name=itis>{{ITIS |id=684950 |taxon=''Xylocopa californica''}}</ref>

==Distribution== There are approximately 400 species worldwide of the genus ''Xylocopa.''<ref name=":1">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.</ref> ''X. californica'' is typically found in California, Nevada, Oregon, Washington, Utah, Arizona, New Mexico, Texas, and Northwestern Mexico.<ref>[https://stri.discoverlife.org/mp/20m?r=.125&la=33.75&lo=-107.8&kind=Xylocopa+californica&place=target ''X. californica'' distribution map at DiscoverLife]</ref> It is especially abundant, along with ''X. sonorina'', in the Central Valley and in Southern California, including the Mojave Desert. They are agriculturally beneficial insects and pollinators of diverse California chaparral and woodlands and desert native plant species.<ref>''California Insects''; Jerry A. Powell, Charles L. Hogue; 1989; University of California Press.</ref><ref>[http://stri.discoverlife.org/mp/20q?guide=Apoidea_genera Discoverlife.org: ''Xylocopa californica'']</ref> 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.<ref>{{Cite journal |last=Chappell |first=Mark A. |date=1982 |title=Temperature Regulation of Carpenter Bees (Xylocopa californica) Foraging in the Colorado Desert of Southern California |url=https://www.jstor.org/stable/30157890 |journal=Physiological Zoology |volume=55 |issue=3 |pages=267–280 |doi=10.1086/physzool.55.3.30157890 |jstor=30157890 |issn=0031-935X}}</ref>

==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.<ref name=":0">{{Cite journal |last=Ackerman |first=Arthur J. |date=1916 |title=The Carpenter-Bees of the United States of the Genus Xylocopa |url=https://www.jstor.org/stable/25003718 |journal=Journal of the New York Entomological Society |volume=24 |issue=3 |pages=196–232 |jstor=25003718 |issn=0028-7199}}</ref> The California carpenter bee is all black, with bluish/greenish reflections. The males typically have at least a few light hairs on the pronotum (dorsal prothorax) and the abdominal segments.<ref>[http://bugguide.net/node/view/7698 BugGuide.Net: Species − ''Xylocopa californica'']</ref> 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. They have dark wings without stigma and are 13–30 mm long overall.<ref name=":1" />

== Foraging behavior == ''Xylocopa californica'' has been observed to rob nectar from ocotillo, ''Fouquieria splendens'', and are determined to be their primary pollinator in the Big Bend National Park, Texas, USA.<ref>Richardson, S.C. 2004. Are Nectar-robbers Mutualists or Antagonists?. Oecologia. 139: 246-254.</ref> They rob the nectar from flowers by chewing a hole on the side of the flower and taking the nectar without participating in pollination.<ref name=":1" /> They like both nectar and pollen, except the pollen sources seem more specific; they prefer the pollen from the creosotebush (''Larrea tridentata'') and mesquite (''Prosopis glandulosa'').<ref name=":2">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.</ref> They tend to visit larger open flowers due to their large size.<ref name=":1" /> The foraging behavior consists of three movements- fast forward flight, hovering and perching or walking on the flower blossoms <ref name=":3">Chappell, M.A. 1982. Temperature Regulation of Carpenter Bees (''Xylocopa californica'') Foraging in the Colorado Desert of Southern California. Physiological Zoology. 55: 267-280.</ref>

<gallery mode="packed"> File:Fouquieria splendens flowers 2.jpg|''Fouquieria splendens'' File:Larrea tridentata - Flickr - aspidoscelis.jpg|''Larrea tridentata'' File:Prosopis glandulosa kz4.jpg|''Prosopis glandulosa'' </gallery>

=== Floral sonication === Floral sonication is essential for the foraging of many Hymenoptera.<ref name=":4">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.</ref> ''X. californica'' performs floral sonication to obtain pollen.<ref name=":5">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.</ref> They do this by gripping the poricidal anthers 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.<ref name=":4" /> This process allows for pollination to happen.

The vibration frequency is different throughout their body; their head's natural vibration is 87 Hz, and their abdominal terga is 163 Hz.<ref name=":5" />''X. californica'' can adjust its frequency to different types of flowers.<ref name=":4" />

=== Temperature regulation === ''Xylocopa californica'' inhabit the deserts of southwestern North America and endure high temperatures while they forage.<ref name=":3" /> Foraging in these high temperatures may cause thermoregulatory problems for the bee, which is increased by the heat released from the muscular activity needed for their flight.<ref name=":3" /> 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.<ref name=":3" /> On the other hand, they can not withstand temperatures lower than 10-15 °C.<ref name=":3" />

== Reproduction == === Mating behavior === ''Xylocopa californica'' has many types of mating behaviors.<ref name=":6">Alock, John. 1991. Mate-Locating Behavior of ''Xylocopa californica'' ''arizonensis'' Cresson (Hymenoptera: ''Anthophoridae)''. Journal of the Kansas Entomological Society. 64: 349-356</ref> These include hovering near sites and chasing away other males, exhibiting female-defense polygyny.<ref name=":6" /> 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; in particular, they look for virgin females because females only mate once in their lifetime.<ref name=":6" /><ref name=":7">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</ref> After a few seconds, they separate, and the male returns to its hovering area.<ref name=":7" /> Other males may patrol more than one nest and shuttle throughout many sites in a day.<ref name=":6" /> If they are not patrolling the nests, then they may exhibit scramble competition at flowering sites, where they hope to catch a female.<ref name=":6" /> The males are territorial, but they do not have a stinger.<ref name=":1" />

=== Nesting === ''Xylocopa californica'' carve their nest in wood.<ref name=":1" /> They dig into the wood using their sharp mandibles while they vibrate their body- they do not eat the wood.<ref name=":1" /> They dig a tunnel in substrates such as live or dead wood and hollow stems of ''Yucca'' and ''Agave'' plants, then dig to the right and left, creating a T-shape nest.<ref name=":1" />

Their nest's success depends on the available pollen and nectar found in the area.<ref name=":2" /> 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.<ref name=":2" />

== Predators == [[File:Ladder-backed_Woodpecker_Portal_Rd_TAS_Bluebird_Survey_Portal_AZ_2016-06-10at06-18-264_(40841286313).jpg|thumb|Ladder-backed woodpecker]] ''Xylocopa 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.<ref name=":2" /> And the bee fly, ''Anthrax simson,'' is a parasite of their nests <ref name=":2" />

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.<ref>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.</ref>

== Disease == The fungus ''Ascosphaera apis'' is generally found in the larva of the European honey bee, ''Apis mellifera'''','' causing the larva to be mummified''.''<ref name=":8">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.</ref> 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.<ref name=":8" /> ''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.<ref name=":8" />

== Subspecies == The species has three named subspecies, defined solely by coloration and geography:<ref name=itis/> *''Xylocopa californica arizonensis'' Cresson, 1879 *''Xylocopa californica californica'' Cresson, 1864 *''Xylocopa californica diamesa'' Hurd, 1954

== Gallery == <gallery mode="packed"> 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'' </gallery>

==References== {{Reflist}}

==External links== *[http://stri.discoverlife.org/mp/20q?guide=Apoidea_genera Discoverlife.org: Photo gallery of ''Xylocopa californica'' (Western Carpenter Bee)] — ''with list of host plants''. *[http://bugguide.net/node/view/7698 BugGuide.Net: ''Xylocopa californica'' — Western Carpenter Bee] — ''images''.

Category:Hymenoptera of North America Category:Insects of Mexico Category:Insects of the United States Category:Fauna of California Category:Fauna of the Southwestern United States Category:Fauna of the California chaparral and woodlands Category:Fauna of the Great Basin Category:Fauna of the Mojave Desert Category:Natural history of the Central Valley (California) Category:Xylocopinae Category:Insects described in 1864 Category:Taxa named by Ezra Townsend Cresson