American Bumble Bee

American Bumble BeeBombus pensylvanicus

Texas Master Naturalist

2020 Certification Pin

Bumble Bee Physiology and Foraging

Source: Bumble Bee Conservation Trust; The Xerces Society/Rich Hatfield and Eric Lee Mader

• Can fly in cold/wet conditions

• Learn to access resources

• Visit diverse flowers

• Use their strength to their advantage

Physiology Intelligence Long-tongues Innovation

Bumble Bee Life History

• Annual Species

• Queen Emerges in the Spring Gravid

• Cavity & Ground Nester

• Incubates eggs when establishing a new nest

Bumble Bee Life History

Large Nest Sizes

Cuckoos?

Fall Mating & Dispersal

Winter Hibernation

State of the Bumble Bees of North America

Source: IUCN Red List

Critically Endangered

Endangered

Vulnerable

Near Threatened

Least Concern

Data Deficient

Bumble Bees of Texas

Source: IUCN Red List, Photo: Ross Winton

Bumble Bee Species IUCN Rank

Bombus griseocolisLeast

Concern

Bombus impatiensLeast

Concern

Bombus bimaculatusLeast

Concern

Bombus variabilis*Critically

Endangered

Bombus pensylvanicus* Vulnerable

Bombus auricomusLeast

Concern

Bombus fervidus Vulnerable

Bombus fraternus Endangered

American Bumble Bee

Bombus pensylvanicus

1914-Present

American Bumble Bee

Bombus pensylvanicus

Current vs. Historic Range

Causes of Population Decline

Source: Jack Ohman, The Sacramento Bee 5/7/2013

Causes of Population DeclineHabitat Loss

Photo: Eric Mader, Matthew Shepherd

Causes of Population DeclinePesticides

Source: USGS Pesticide National Synthesis Project

Causes of Population DeclinePesticides

Source: IUCN Red List, Photo: Ross Winton

Causes of Population DeclineDisease & Competition

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• Moving non-native species around the globe

• Moving and amplifying pathogens• Nosema bombi

• Unregulated in 48 U.S. States• CA and OR exceptions

Agricultural Pollination Services

Tomatoes

Peppers

Eggplant

Blueberries

Cranberries

Clover

Squash

Melon

Buzz Pollination~ 8% of all flowers are primarily pollinated by buzz pollination

Shooting stars (Dodecatheon)

Sennas (Senna)

Pitcher plants (Heliamphora)

Flax lilies (Dianella)

Madrone (Arbutus)

Guinea flowers (Hibbertia)

Some members of Solanaceae family (eggplant, tomato, potato)

Some members of genus Vaccinium (blueberry, cranberry)

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Pollination ServicesAureolaria, Bidens, Cirsium, Cucurbita, Daucus, Eupatorium, Galactia, Hydrolea, Hypericum, Kuhnistera, Liatris, Malus, Medicago, Opuntia,

Pontederia, Rhus, Richardia, Rubus, Spiraea, Vernonia and Vicia. Abutilon, Actinomeria, Aesculus, Agastache, Amelanchier, Amorpha, Antennaria, Arctium, Asclepias, Aster, Astragalus, Baptisia, Blephilia,

Boltonia, Brauneria, Campanula, Cassia, Cephalanthus, Cerastium, Cercis, Circaea, Claytonia, Clematis, Collinsia, Convolvulus, Coreopsis,

Cornus, Crataegus, Crotalaria, Cuphea, Delphinium, Desmodium, Dentaria, Dianthera, Dicentra, Diospyros, Dipsacus, Dodecatheon,

Eryngium, Frasera, Gaura, Gentiana, Geranium, Gerardia, Gymnocladus, Helenium, Helianthus, Heliopsis, Heuchera, Hibiscus, Hydrangea,

Hydrophyllum, Impatiens, Ipomoea, Iris, Isopyrum, Krigia, Lantana, Leonurus, Lepedeza, Linaria, Lippia, Lithospermum, Lobelia, Lonicera,

Ludwigia, Lycopus, Marrubium, Martinia, Melilotus, Mertensia, Mimulus, Monarda, Nelumbo, Nepeta, Oenothera, Orobanche, Oxalis, Pastinaca,

Pelatostemum, Pentstemon, Philadelphus, Phlox, Physostegia, Plantago, Podophyllum, Polemonium, Polygonatum, Polygonum, Polytaenia,

Potentilla, Prenathes, Prunella, Prunus, Psoralea, Pycnanthemum, Pyrus, Ranunculus, Rhamnus, Ribes, Robinia, Rosa, Rudbeckia, Ruellia,

Sagittaria, Salix, Scutellaria, Seymeria, Sida, Silene, Silphium, Sium, Solanum, Solidago, Specularia, Stachys, Staphylea, Strophostyles,

Stylosanthes, Symphoricarpus, Tecoma, Teucrium, Tilia, Tradescantia, Triosteum, Trifolium, Uvularia, Verbascum, Verbesina, Verbina,

Vernonia, Veronica, Viburnum, Viola, Vitus and ZiziaPh

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Get InvolvedKeep Gathering Data

Get InvolvedKeep Gathering Data

Get InvolvedEstablish Habitat

Create pollinator habitat in your backyard

Get involved in local planting and restoration

events

Encourage your local city or town to become an

official Bee City

American Bumble BeeBombus pensylvanicus

• Iconic Texas Bumble Bee

• Hard Working & Adaptable

• Provide Vital Services

American Bumble BeeBombus pensylvanicus

Texas Master Naturalist

2020 Certification Pin