The Relationship Between Foraging Resources and Native Bee Abundance

Guidelines for Site Assessment and Restoration

Steven K. Javorek and Matt C. Grant, Agriculture and Agri-Food Canada, Kentville, NS

• Blueberry Pollinators in Prince Edward Island• Comparative Pollination Effectiveness

• Bee Abundance and Diversity

• Linking Bee Abundance to Landscape Pattern• Foraging Resource Index (FRI)

• Site Assessment Technique• Identifying Spatial and Temporal Gaps in Foraging Resources

• Restoration and Development of New Blueberry Land

Discussion Overview…

… diversified pollination strategy that maximizes the use of managed and native bees.

Blueberry Pollination StatisticsFlowers / Minute: 8

Success Rate: 24%

Deposition / Visit: 12

Honey Bees (Apis mellifera)

Blueberry Pollination StatisticsFlowers / Minute: 8

Success Rate: 85%

Deposition / Visit: 28

Alfalfa Leafcutting Bees (Megachile rotundata)

Blueberry Pollination StatisticsFlowers / Minute: 13

Success Rate: 97%

Deposition / Visit: 51

Bumble Bees (Bombus)

Blueberry Pollination StatisticsFlowers / Minute: 7

Success Rate: 96%

Deposition / Visit: 46

Andrena

Blueberry Pollination StatisticsFlowers / Minute: 8

Success Rate: 24%

Deposition / Visit: 12

Halictus

Blueberry Pollination StatisticsFlowers / Minute: 4

Success Rate: ?

Deposition / Visit: ?

Lasioglossum

Blueberry Pollination Statistics*Flowers / Minute: 11

Success Rate: 100

Deposition / Visit: 72* Only 2 bee studied

Osmia

Comparative Pollinator Equivalencies

0 1 2 3 4 5 6 7 8 9

Osmia*

Halictus

Andrena

Bumble Bees

Leafcutting Bees (F)

Leafcutting Bees (M)

Honey Bees

Pollination Equivalency

STUDY SITES

ANDERSON RDBRISTOL

ROLLO BAY

GOOSE RIVER

HARMONY

HARPER RD

Dominant Native Blueberry Pollinators in PEI

Dominant Native Blueberry Pollinators in PEI

0

5

10

15

20

25

30

35

STEM SOIL CAVITY MANAGED

NESTING GUILD

SPEC

IES

NESTING GUILDS

7%

71%

16%

6%

STEM SOIL CAVITY

MANAGED

MANAGED

The Relationship between Land Cover and Bee Abundance in Blueberry Agro-EcosystemsForaging Resource Index (FRI)

Bees Require …A suitable nesting substrate from which they can access adequate forage over the course of individual or colonial life spans.

p<0.001

r2=0.54

nFRI = ∑ (Pi × Ri)

i=1

Foraging Resource Index

Resource Value Description

0 Resourcesless

1 Scanty forbs or shrubs (<1/ m2) and low diversity (1-2 species)

2 Either scattered forbs or shrubs (≈1/ M2 ) and low diversity OR scanty but more diverse (> 2 species).

3 Either dense (≈ 4-6 forbs or shrubs/ m2) and diverse (≈2-3 abundant species) OR not dense (2-3/ m2) but more diverse (3-5 abundant species).

4 Either dense (≈ 4-6 forbs or shrubs/ m2) and highly diverse (> 5 species) OR of high density (> 6 species/ m2) and not so diverse (3-5 abundant species).

5 Exceptionally dense (> 6 forbs or shrubs/ m2) and diverse (> 5 species).

Definitions of floral resource values assigned to polygons in the FRI analysis.

Floral Resources

nFRI = ∑ (Pi × Ri)

i=1

FORAGING RESOURCE INDEX

nFRI = ∑ (Pi × Ri)

i=1

Temporal Scale• Pre-Bloom• During Bloom• Early Summer• Late Summer

FORAGING RESOURCE INDEX

Plant Communities and Land Cover

Floral Abundance: Example - Edge

Salix discolorSalix humilisCaltha palustrisPrunus pensylvanicaNemopanthus mucronataAcer rubrumRhodora canadensisCahaedaphna calyculataArctostaphylos uvi-ursiLonicera CanadensisAntennaria neglectaTaraxacum officinale

Clintonia borealisMaianthemum canadensaCypripedium acaulaSalix bebbianaRumex acetosellaArenaria laterifloraTrientalis borealisRibes lacustreAronia prunifoliaSorbus AmericanaViburnum cassinoidesFragaria virginiainaPrunus virginianaIlex verticilataViola cucullataCornus canadensisLedum groenlandicumHieracum pillosella

Habenaria cavellataHabenaria laceraHabenaria psycodesSpiranthes learaPolygonum aviculareRanunculus repensThalictrum polygonumCorydalis semipervironsRaphanus raphanistrumBrassica kaberSanacenia purpureaDrosera rotundifoliaDrosera intermediaSpirea latifoliaSpirea tomentosumRubus pubescensRubus idaeusRosa virginanaVicia craccaVicia tetraspermaHypericum perforatumHypericum canadenseEpilobium angustifoliumEpilobium adenocaulonOenothera biennisOenothera perennisAralia nudicaulisAralia hispidaPyrola ellipticaKalmia angustifolia

Gaylussacia baccataGaleopsis tetrahitLycopus americanusLycopus uniflorusSolanum dulcameraVerbascum thapsisDiervilla loniceraViburnum trilobrumLobelia inflataSolidago canadenseSolidago graminifoliaErigeron strigosusErigeron CanadensisRudbeckia serotinaAchillia millefoliumChrysabthemum leucanthemumHieracium aurantiacumHieracium floribundun

Melilotus officinalisMelilotus albaImpatiens bifloraDacus carotaGaultheria procumbensLinnaea borealisEupatorium maculatumSolidago bicolourSolidago puberulaSolidago nemoralisSolidago rugosaAster cordifoliusAster umbellateAster puniceusAster lateriflorusAster novi-belgiiAnapfalis margaritaceaGnaphalium uliginosumBidens frondosaTanacetum vulgareSenencio jacobaeaCirsium vulgareSonchus arvensisPrenanthes trifolataLactuca biennis

Pre-Bloom

During Bloom

Early Summer Late Summer

Flowering Plant Survey: Anderson Road Blueberry Agro-Ecosystem

TAXA APRIL MAY JUNE JULY AUGUST SEPTEMBER OCTOBER

Colletes (inaequalis, validis)

Colletes

Hylaeus

Andrena

Andrena (Cnemidandrena)

Protandrena

Perdita

Calliopsis

Agochlora pura

Agochlorella striata

Agapostemon (females)

Agapostemon (males)

Halictus (females)

Halictus (males)

Lasioglossum (females)

Lasioglossum (males)

Sphecodes

Macropis nuda

Stelis

Coelioxys

Megachile

Hoplitis

Osmia

Ceratina calcarata

Nomada

Triepeolis

Epeolis

Melissodes

Bombus

Psithyrus

Seasonal Bee Activity Periods

PRE-BLOOM

BLOOM

EARLY SUMMER

LATE SUMMER

Site Assessment

Identifying Spatial and Temporal Foraging Gaps

Land Cover Class PercentAbandoned Land 1.91

All Edge 0.85

Blueberry Crop 19.04

Blueberry Sprout 11.69

Bog 1.99

Cranberry 0.48

Deep Marsh 2.29

Dirt Road 0.97

Forest Non Resource 15.75

Forest Resource 25.46

Grain Field 1.71

Hay Field 4.68

Hedgerow 0.28

Homestead 0.59

Meadow 1.30

Open Water 3.23

Pasture 0.08

Paved Road 0.23

Potatoes 1.06

Regeneration 2.47

Salt Marsh 0.06

Sand Dune 3.23

Shallow Swamp 0.24

Shrub Swamp 0.17

Shrubby 0.27

nFRI = ∑ (Pi × Ri)

i=1

… local bee populations are determined by resources available within a 1000 metre radius.

The Spatial Component

Land Cover Class PercentAbandoned Land 2.66

Blueberry Crop 15.08

Blueberry Sprout 21.70

Bog 0.32

Cranberry 0.73

Deep marsh 0.66

Dirt Road 2.05

Forest No Resource 15.82

Forest Resource 22.17

Grain Field 6.84

Hay Field 4.82

Hedgerow 0.28

Homestead 0.35

Meadow 0.46

Open Water 1.35

Pasture 0.34

Potatoes 0.70

Regeneration 1.64

Shallow Swamp 0.68

Shrubby 0.03

Edge All 1.31

nFRI = ∑ (Pi × Ri)

i=1

FORAGING RESOURCE INDEXLand Cover

nFRI = ∑ (Pi × Ri)

i=1

Grid Cell = 100 x 100 metres

Foraging Resource Index: Site Assessment

Foraging ResourceIndex

No ResourcesVery LowLowModerateHighVery High

PRE-BLOOM

Anderson Road Blueberry Agro-Ecosystem

DURING BLOOM

Foraging ResourceIndex

No ResourcesVery LowLowModerateHighVery High

Anderson Road Blueberry Agro-Ecosystem

Foraging ResourceIndex

No ResourcesVery LowLowModerateHighVery High

EARLY SUMMER

Anderson Road Blueberry Agro-Ecosystem

Foraging ResourceIndex

No ResourcesVery LowLowModerateHighVery High

LATE SUMMER

Anderson Road Blueberry Agro-Ecosystem

Site Assessment

Moderate Resource Site

0

10

20

30

40

50

60

70

80

90

Radius Around Field

Fora

ging

Res

ourc

e In

dex

500m750m1000m

PRE-BLOOM

0

10

20

30

40

50

60

70

80

90

Radius Around Field

Fora

ging

Res

ourc

e In

dex

500m750m1000m

DURING BLOOM

0

10

20

30

40

50

60

70

80

90

Radius Around Field

Fora

ging

Res

ourc

e In

dex

500m750m1000m

EARLY SUMMER

0

10

20

30

40

50

60

70

80

90

Radius Around Field

Fora

ging

Res

ourc

e In

dex

500m750m1000m

LATE SUMMER

Site Assessment

Low Resource Site

0

10

20

30

40

50

60

70

80

90

Pre Bloom

Fora

ging

Res

ourc

e In

dex

PRE-BLOOM

0

10

20

30

40

50

60

70

80

90

Pre Bloom

Fora

ging

Res

ourc

e In

dex

DURING BLOOM

Sprout

0

10

20

30

40

50

60

70

80

90

Pre Bloom

Fora

ging

Res

ourc

e In

dex

EARLY SUMMER

0

10

20

30

40

50

60

70

80

90

Pre Bloom

Fora

ging

Res

ourc

e In

dex

LATE SUMMER

Restoration

Edges

Create and Enhance Regeneration Areas

Leave Strip of Blueberry to Flower in Sprout Year

OR

Modify Crop/Sprout Mosaic

Shelterbelts

Summary …

• We need a diversified pollination strategy for the lowbush blueberry industry.

• Managed Bees (Honey Bees and Leafcutting Bees)

• Native Bees

• Native bee abundance at blueberry strongly influenced by local resource availability (1000 metres).

• Site assessment can identify spatial and temporal gaps in foraging resource availability.

• Assessments can be used to:

• Understand potential native bee pollination contribution

• Strategically guide restoration efforts

• Maintain critical bee habitat when new land is being developed.

Acknowledgements …

Chris Jordan

PEI Wild Blueberry Growers Association

Jasper Wyman and Sons

Lorne Valley Ranch

Thank You !