MN Bee Atlas: Bumble Bees - University of Minnesota...MN Bee Atlas: Bumble Bees Elaine Evans &...

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MN Bee Atlas: Bumble Bees

Elaine Evans & Britt Forsberg

Photo: Eileen Miller

Bumble bee look-alikes

Characteristics:

• Antenna variable

• No pollen basket

• One pair of wings

• Short, blunt mouthparts

Flies that mimic coloration

Clearwing Moth

Photo by TexasEagle

Long curled tongueLong straight antennaeNo waist

Characteristics:

• Large size, robust body

• Yellow hair on thorax

• Shiny abdomen

• Hairy scopa on hind legs, not pollen basket

• Males with yellow markings, not hairs, on face

• Nest in hard wood

Photo: Jennifer Hopwood

Bumble bee look-alikes

Large Carpenter Bees (Xylocopa virginica)

Characteristics:

• Small size

• Hairy scopa on hind legs, not pollen basket

Photo: Jennifer Hopwood

Bumble bee look-alikes

Andrena

Males

•No stinger

•“Beard” on mandible

• Often smaller than females

• Often with white or yellow facial hair

• Some species have enlarged eyes

Females

• Often larger than males

•Sting present

Female bumble bee leg

(non-parasitic)

Male bumble bee leg

Photos: Sam Droege

Big eyesLong antennae

Regular eyesRegular antennae

Photos: Sam Droege

Identifying bumble bees to species

Color patterns can be important, but are not always reliable

Images by Elaine Evans / Xerces Society

Identifying bumble bees to species

Things to look at other than color patterns

Start with yellow sections

then follow numbers

Read descriptions to

see if it fits

Color patterns can vary

in the real world

Earliest emergence records in Wisconsin

April May June July August September

Queens WorkersMales

Medler and Carney 1963

Bombus impatiens / Common Eastern bumble bee

• Nest underground at

various depths

• Queens come out mid-

spring

•Medium tongue length

•Select food plants:

Cirsium (Thistles),

Eupatorium, Solidago

(Goldenrods)

Photo: Gary Zamzow

Bombus impatiens / Common Eastern bumble bee

• Very common species

• Used commercially;

expanding in range

• IUCN Status: Least

Concern

Photo: Gary Zamzow

Hatfield et al. 2014; Xerces Society

• Thorax mostly

yellow; wing bases

yellow; usually with

black spot centrally

•T1 Yellow and all

other abdominal

segments black

Male

Female

Bombus impatiens / Common Eastern bumble bee

Illustrations: Evans

Bombus bimaculatus (Two-spotted bumble bee)

• Nests underground but

also on surface, and uses

nesting boxes

• Queens emerge early in

the spring

•Tongue length: medium

• Select food plants:

Cirsium (Thistles),

Hypericum (St. John’s

Wort), Rosa, Solidago

(Goldenrods), Vicia

(Vetches)

Photo: Patricia Nankey

• Common species

• IUCN Status: Least

Concern

Photo: Gary Zamzow

Bombus bimaculatus (Two-spotted bumble bee)

Hatfield et al. 2014; Xerces Society

Male

Female

Bombus bimaculatus (Two-spotted bumble bee)

• Thorax mostly

yellow; wing bases

yellow; black spot

centrally

•T1 Yellow; T2 with

two yellow “W”; all

other abdominal

segments black in

Illustrations: Evans

Bombus griseocollis (Brown-belted bumble bee)

• Nest on ground or above

the surface, including in

outbuildings

• Queens come out mid-

spring

•Tongue length: medium

•Select food plants:

Asclepias (Milkweeds),

Cirsium (Thistles),

Helianthus (Sunflowers),

Solidago (Goldenrods),

Rhus (Sumacs)

Photo: Hannah Gaines

• Common species

• IUCN Status: Least

Concern

Photo: Gary Zamzow

Hatfield et al. 2014; Xerces Society

Bombus griseocollis (Brown-belted bumble bee)

• Thorax mostly

yellow; wing

bases yellow;

black spot

centrally

•T1 Yellow

•T2 with rusty

“swoosh”

•All other

abdominal

segments blackMale

Female

Bombus griseocollis (Brown-belted bumble bee)

Illustrations: Evans

Bombus citrinus (Lemon cuckoo bumble bee)

• Parasite of B. impatiens,

bimaculatus, vagans

• Range: All of MN

• Females: Thorax usually all yellow,

T1-T2 usually black, T3 usually

yellow, T4-T6 black

• Males: T1-T2 yellow, T3 usually

yellow, T4-T7 black

• Very short malar space

• No pollen basket

• Similar species: sandersoni,

vagans, rufocinctus, perplexus

Photo: Gary Zamzow

Hatfield et al. 2014; Xerces Society

Bombus citrinus (Lemon cuckoo bumble bee)

• Common species

• IUCN Status: Least

Concern

Bombus ternarius / Tri-colored bumble bee

• Nest underground,

sometimes at large depths

in sandy soil

• Queens come out early

spring

•Tongue length: short

•Select food plants:

Asclepias (Milkweeds),

Rubus, Solidago

(Goldenrods), Vaccinium •

Photo: Alan Eaton

• Common species

• IUCN Status: Least

Concern

Photo: Gary Zamzow

Hatfield et al. 2014; Xerces Society

Bombus ternarius / Tri-colored bumble bee

• Thorax mostly

yellow; with

black “thumb

tack” or band

•T1 Yellow

•T2-T3 Rusty

•T4 Yellow

•T5 black

Male

Female

Bombus ternarius / Tri-colored bumble bee

Illustrations: Evans

Bombus huntii / Hunt’s bumble bee

Male

• Rare in MN, only

encountered in far

western part of

the state

Map: Hatfield et al. 2014; Xerces SocietyIllustration: Evans

Bombus rufocinctus / Red-belted bumble bee

• Nest under or above

ground, including in

domiciles

• Queens come out late in

spring

Photo: R. Bercha

Bombus rufocinctus / Red-belted bumble bee

• Common species

• IUCN Status: Least

Concern

Hatfield et al. 2014; Xerces Society

• Small bodied;

short hairs;

short face

•Variable color

pattern

Male

Female

Bombus rufocinctus

Illustrations: Evans

Bombus auricomus / Black and gold bumble bee

• Queens and workers large

•Dark wings

•Usually yellow hairs on top of head

• T1, T5 black, T2-T4 yellow

• Large males with large eyesPhoto: Molly MurrayIllustrations: Evans

• Nests under and above

ground, will also nest in urban

areas

• Known to nest in wooden

bumble bee homes

• Colonies 30-50 workers

• Queens come out in late

spring

• Long tongue

Hatfield et al. 2014

Bombus pensylvanicus /American bumble bee

• Queens large, workers medium to large

• Wings dark in color

• Malar space longer than wide

• Ocelli close to suborbital line

•Males often with orange on Ab 7

Photo: Jennifer Hopwood

Illustrations: Evans

51% decline

• Nest at surface or above

ground

• Queens emerge late in spring

• Colonies 40 -100 workers

• Aggressive in defense of nest

• Listed as a species of concern

in WI

Hatfield et al. 2014

auricomus pensylvanicus

Difficult pairs: Females

University of Illinois, Cameron et al

B. pensylvanicusLong sharp spine at top of basitarsus

B. auricomusShort spine at top of basitarsus

Also basitarsus, just below pollen basket, outer tip of segment

Bombus terricola / Yellow-banded bumble bee

• Medium sized

• Wings dark

• T1, T4 black, T2-T3 yellow, T5

black with fringe of yellow

• Malar space wider than long

(round face)

• Similar to B. pensylvanicus, but

smaller

Pocket guide and Wanted posters

available

Photo: Jodi DeLong

50% decline

• Nest underground, under

straw piles

• Queens emerge early in

spring

•Short tongue, will rob nectar

•Habitats: Close to or within wooded areas

•Listed as a species of

concern in WI

Hatfield et al. 2014

Bombus fervidus /Golden Northern bumble bee

• Queens and workers large

• Long tongue

• Black hairs on head

•Long face

Photo: MJ Hatfileld, S DroegeIllustrations: Evans

•Nests on surface, tall grass,

sometimes underground

• Colonies are large (100-

200)

• Aggressive in defending

their nests

• Habitats: Open farmland and fields

• Recent survey shows this

bee in rapid decline

•IUCN Status: Vulnerable

Hatfield et al. 2014, the Xerces Society

Bombus borealis /Northern amber bumble bee

• Workers medium in size

•Long tongue

• Face and top of head covered

with yellow-white hairs

• T1 – T4 amber yellow, 5-6 black

• Malar space longer than broad

•More common in northern MN

Photo: Naomi SmithIllustrations: Evans

7% decline

• Nests underground but

uses nesting boxes, and

may be fairly flexible

• Queens emerge later in

the spring

• Colonies may reach

100 workers

• Habitats: Close to or within wooded areas.

Hatfield et al. 2014

fervidus borealis

Difficult pairs: Females

Predominantly black hairs on face and top of head

Side of thorax mostly yellow

Predominantly yellow hairs on face and top of head

Side of thorax with large patch of dark hairs

Illustrations: Evans

pensylvanicus fervidus borealis

Difficult groups: Males

Often with orange on Ab 7 Yellow on face and top of head

Side of thorax with many black hairs

Illustrations: Evans

Bombus vagans (Half-black bumble bee)

• Habitat: Various; more

common in forests

• Forages in deep shade

• Range: All of MN; more

common in north

• Nesting: mostly

underground, sometimes

aboveground

• Colony size: 70-110

Photo: Joel GardnerPhoto: Joel Gardner

Bombus vagans (Half-black bumble bee)

• T1-T2 yellow, T3-T6/7 black

(males often with yellow hairs

on far sides of tergites)

• Long malar space (horsey

face)

• Usually yellow hairs on top of

head

• Black hairs on thorax usually

confined to spot in middle

• Male antenna with F1 long,

hairless

• Similar species: sandersoni,

rufocinctus, perplexus, affinis

• Common species

• IUCN Status: Least

Concern

Photo: Gary Zamzow

Hatfield et al. 2014; Xerces Society

Bombus vagans (Half-black bumble bee)

Bombus sandersoni (Sanderson’s bumble bee)

• Habitat: In or near woods

• Range: Northern MN

• Nesting: underground

Photo: Margarita Miklasevskaja, PCYU, with funding from NSERC-CANPOLINPhoto: Joel Gardner

Bombus sandersoni (Sanderson’s bumble bee)

• T1-T2 yellow, T3-T6/7 usually

black (T5 sometimes yellow)

• Moderate malar space

• May have all black hairs on top

of head

• Usually at least a few black hairs

by wing bases; sometimes

complete black band

• Male antenna with F1 short,

fringed with hairs

• Similar species: vagans,

rufocinctus, perplexus, affinis

• Common species

• IUCN Status: Least

Concern

Photo: Gary Zamzow

Hatfield et al. 2014; Xerces Society

Bombus sandersoni (Sanderson’s bumble bee)

vagans sandersoni

Difficult groups:

Males: antennae

Bombus affinis (Rusty-patched bumble bee)

• Habitat: Various; recent sightings

mostly in urban parks/gardens

• Range: Most of MN; more common

in southeast

• Nesting: underground

• Colony size: up to 200

• Frequent nectar robber

• In decline compared to pre-1997

prevalence

• Federally listed as endangered

Photo: Joel Gardner

Bombus affinis (Rusty-patched bumble bee)

• T1 yellow, T2 yellow with orange

patch (except queens), T3-T6/7 black

• Usually black band between wings

• Hair on head usually all black

• Similar species: griseocollis,

vagans, sandersoni, rufocinctus,

perplexus

• Rare, declining species

•Nearly 50% decline in

range

• Over 90% decline in

relative abundance

• IUCN Status: Critically

Endangered

Photo: Gary Zamzow

Hatfield et al. 2014; Xerces Society

Bombus affinis (Rusty-patched bumble bee)

Bombus perplexus confusing bumble bee

• No obvious spot on thorax

•This species is highly

variable in coloration

• Abdomen with yellow on

bands 1 to 3

Illustrations: Evans

Nests underground

Males patrol circuits

Hatfield et al. 2014

• Common species

• IUCN Status: Least

Concern

Bombus bohemicus (Ashton’s cuckoo bumble bee)

• Parasite of B. affinis, terricola

• Range: All of MN

• Declining along with hosts.

Species of concern in WI.

• Sides of thorax with black hair, T1

black (females) or yellow (males), T2

black, T3-T6/7 mixed black, yellow,

white (especially female T4)

• Hair on head mostly black

• No corbicula

• Similar species: insularis, flavidus

Photos: Margarita Miklasevskaja, PCYU, with funding from NSERC-CANPOLIN

B. bohemicus aka ashtoni

• Rare, declining species

•Over 95% decline in

range

• Over 95% decline in

relative abundance

• IUCN Status: Critically

Endangered

Photo: Gary Zamzow

Hatfield et al. 2014; Xerces Society

Bombus bohemicus (Ashton’s cuckoo bumble bee)

MN Bee Atlas: Bumble Bee Surveys

Survey Protocols

• Conduct three surveys: late June, mid July, early August

• Observe flower patch for bee activity. If there is no activity, move ~1 mile down the road.

• If there is bee activity, begin survey.

• Start timer and collect bumble bees from flowers into vials

for 10 minutes of collecting time

• Record and release individuals of all identifiable species

• Photograph and record individuals of all unidentifiable species

• Repeat until data has been collected at five locations