Biology & Habitats of Native Bees Natural Resources Conservation Service, 20 August 2009 Robbin Thorp, UC Davis

A “Not-A” Bee

Another “Not-A” Bee A Sphecid Wasp (“You are what you eat”)

A Bee The European Honey Bee, Apis mellifera Honey bee on almond

What are Bees (Apoidea)? Derived wasps that use pollen (not animal) protein to feed their young They use nectar as flight fuel They have branched hairs, and other adaptations for obtaining food from flowers They provide an important ecological service to flowering plants: Pollination Many are pollen specialists (oligoleges)

What are Bees (Apoidea)? There are over 19,500 species (ca 20-30K) –More diversity than all Mammals + Birds +Reptiles + Amphibians summed together. Greatest diversity is in warm dry areas not wet tropics About 75% are solitary About 15% are cuckoos About 10% are social

You Are What You Eat Food gathering devices

Bee Tongues Forked (Bifid) Plasterer bees have bifid tongue like wasp relatives Adaptation for brood cell construction used to spread cellophane- like polymer lining

Bee Tongues Short Tongued Bee Mining bee Short pointed glossa

Bee Tongues Long Tongued Orchid bee –Elongate tongue longer than body

Pollen Transport Structures Scopa (Brush of hairs) Mining Bee –Most of hind leg plus sides of thorax Digger Bee –Only outer hind leg

Pollen Transport Structures Pollen Moistened Mining bee –Scopa sparse Bumble bee –Corbiculum (concave plate on hind leg)

Pollen Transport Structures Scopa: Abdominal Leafcutting bee –Bum-up position

Bee Diversity Mining Bees Mining Bees –Female –Male –Sexual dimorphism –Haplodiploidy

Bee Diversity Mining Bees Mining Bee –Female –Specialist on Sky Blue (Oligolege) –Unnamed species

Bee Diversity Sweat Bees Sweat Bee –Female Sweat Bee –Male

Bee Diversity Sweat Bees Green Sweat Bee –Female Green Sweat Bee –Male

Bee Diversity Leafcutting & Mason Bees Leafcutting Bee –Female collecting pollen Leafcutting Bee –Female cutting leaf

Bee Diversity Leafcutting & Mason Bees Mason Bee –Female Cotton Bee –Male

Bee Diversity Digger, Cuckoo, & Corbiculate Bees Cuckoo Bee –Female Cuckoo Bee –Female

Bee Diversity Digger, Cuckoo, & Corbiculate Bees Sunflower Bee –Female (Specialist) Squash Bee –Female (Specialist)

Bee Diversity Digger, Cuckoo, & Corbiculate Bees Carpenter Bee –Female Small Carpenter Bee –Female

Bee Diversity Digger, Cuckoo, & Corbiculate Bees Yellow Face Bumble Bee –Queen Orchid Bee –Male –with orchid pollinia

Bee Diversity Digger, Cuckoo, & Corbiculate Bees European Honey Bee –Worker Stingless Bee –Worker

Habitat Requirements In addition to food from flowers, bees need habitats for their nests Most are solitary soil nesters –Sand, clay, sandstone, rock –Flat ground, birms, vertical cliffs –Many have specialized habitat requirements Many are tubular cavity nesters –E. g., beetle tunnels, hollow stems Some excavate their own burrows in wood or pith Some social bees use large cavities

Life Cycle of Solitary Bees Female Mining Bee on Goldfields flower head in spring This bee specializes on Goldfields for pollen (Oligolecty)

Life Cycle of Solitary Bees Nest entrance: –open with tumulus (excavated soil) surrounding it. Nest architecture: –Vertical entry shaft –Lateral tunnels –Brood cells: –1) Completed with egg –2) Under construction

Life Cycle of Solitary Bees Brood cell with food mass being formed Brood cell with food mass completed and egg laid on surface

Life Cycle of Solitary Bees Cap of brood cell (inner view) Early larva ready to initiate feeding on pollen provisions

Life Cycle of Solitary Bees Post-feeding larva (summer phase) Pupa (autumnal phase)

Life Cycle of Solitary Bees Early spring bloom of Goldfields and Yellow Carpet at Jepson Prairie Reserve Female Mining bee on pollen host, Goldfields Synchronized annual cycles

Other Bees Managed for Crop Pollination

Bee Nests Alkali Bee –Female on alfalfa –Aggregated nest site –Tumuli

Bee Nests Alkali Bee –Brood cell –Pollen provisions with egg on top

Bee Nests Alkali Bee –Post feeding larvae –Pupa

Bee Nests Alkali Bee –Artificial bee bed –Road sign to protect bees from becoming road kill

Bee Nests Alfalfa Leafcutting Bee –Female collecting pollen from alfalfa –Female cutting leaf

Bee Nests Alfalfa Leafcutting Bee –Cavity nester –Field domicile with bee boards Female into nest with leaf piece

Bee Nests Alfalfa Leafcutting Bee –Female in with pollen Female laying egg on pollen provision

Bee Nests Alfalfa Leafcutting Bee –Brood cells with pollen provisions, egg, larvae Fully developed larvae in cocoons

Bee Nests Mason Bee Blue Orchard Bee (BOB) female on almond flower Drilled hole with mud partitions, pollen, and larvae

Bee Nests Bumble Bee –Corbiculate Bees –Annual societies –Queen emerging from hibernation Incipient nest –Honey pot –Initial brood –Incubated by queen

Bee Nests Bumble Bees –Nest with eggs, pupa, cocoons Nest overview –Egg cups, cocoons –Eggs, larvae, pupae –Nectar storage in old cocoons

Bee Nests Bumble Bees –Mating male/queen Queens entering into hibernation

Conclusions Other bees may be suited for management Unmanaged populations provide valuable services for crop and wildland plants. Knowledge about biology and habitat needs of native bees provides keys to managing them and their habitats.