eastern Victoria Julian Brown Australian National University - - PowerPoint PPT Presentation

Native bees on crops in eastern Victoria

Julian Brown Australian National University

Outline

• Native Victoria bees visiting crops.
• Native vegetation and Victorian bees.
• Making nests for Victorian bees.

Study area

• 6 x orchards (mostly

apple, some cherry)

• 7 x berry farms (blueberry,

raspberry, blackberry)

• 7 x forest sites

Exoneura on Rubus. Photo credit: Alison Hoelzer

Victorian bees visiting crops

Crop visitation

Homalictus sp. Lasioglossum parasphecodes sp. White-banded bee

(Lasioglossum sp.)

Red reed bee

(Exoneura sp.)

Blueberry Apple Raspberry and blackberry Lipotriches sp. Cherry Black reed bee

(Exoneura sp.)

This figure shows the Victorian bees, on the left, that I found visiting these crops on the

• right. A line connecting a bee to a crop indicates that I’ve seen that bee visiting that crop.

The thickness of these lines is roughly proportional to the frequency of visitation, with thicker lines indicating more frequent visitation of that crop by that bee.

Native vegetation and Victorian bees

Nesting substrate

Homalictus sp. Lasioglossum parasphecodes sp. White-banded bee

(Lasioglossum sp.)

Red reed bee

(Exoneura sp.)

Lipotriches sp. Black reed bee

(Exoneura sp.)

Reed bees nest in pithy stems of things like tree ferns and bramble. All the other bees found visiting fruit crops nest in the soil.

Floral resources

Homalictus sp. Lasioglossum parasphecodes sp. White-banded bee

(Lasioglossum sp.)

Red reed bee

(Exoneura sp.)

Lipotriches sp. Black reed bee

(Exoneura sp.)

Natives Crops Weeds

A thicker line connecting a bee to a group of flowers indicates that bee visited that group

• f flowers more frequently.

Flowering time

Red reed bee

(Exoneura sp.)

Natives Crops August September October November December January February March Natives

Reed bees are actively foraging from the end of winter into autumn. Reed bees visit native plants like Acacias and Hakeas before crops start flowering, and visit native plants like Kunzea, Leptospermum, and Pultenaea after crops finish flowering in summer and autumn.

Flowering time

Natives Crops August September October November December January February March Natives

Lipotriches sp. Lasioglossum parasphecodes sp.

Parasphecodes mostly visits Acacia in late winter-early spring. Lipotriches mostly visit Kunzea and Leptospermum in late spring-early summer.

Crops

Flowering time

August September October November December January February March

White-banded bees and Homalictus mostly visited weeds like cape weed and wild Brassica that are found in

• rchards, berry farms, and pastures.

Homalictus sp. White-banded bee

(Lasioglossum sp.)

Crops Weeds Crops

?

Homalictus sp. Lasioglossum parasphecodes sp. White-banded bee

(Lasioglossum sp.)

Red reed bee

(Exoneura sp.)

Lipotriches sp. Black reed bee

(Exoneura sp.)

Landscape associations

Heavily forested Mixed forest-agriculture Landscape types Predominantly agriculture

This figure shows the associations of our crop-visiting bees with different kinds of landscapes on the right. In this figure, a thicker line connecting a bee to a landscape type indicates that we found higher numbers of this kind of bee (in our traps and visiting flowers) in that kind of landscape.

Making nests for reed bees

Why reed bees?

• Visit all surveyed crops in relatively high numbers.
• Carry large amounts of crop pollen (so are probably

good crop pollinators… but not yet sure).

• Pollinate rarer native plants, including some sun orchids

(Thelymitra) and donkey orchids (Diuris).

• Artificial nests are easy to make.

Reed bee nests

Reed bees usually nest in tree ferns in forests, but sometimes nest in cultivated and wild bramble in landscapes without much forest.

Reed bee nests

Reed bees nest in the stumps of old canes cut in previous years (as shown by red arrow in middle picture). They also nest in canes bundled together and housed in PVC pipe (bottom picture).

Thank you

Contact me for further information: julian.brown@anu.edu.au This project is supported by AgriFutures Australia, through funding from the Australian Government Department of Agriculture as part of its Rural R&D for Profit program.