Monitoring Flower Visitation Networks and Interactions between Pairs of Bumble Bees in a Large Outdoor Flight Cage

Different pollinators may vary in their temporal flower-visitation patterns within crops, potentially extending the period pollination may occur. To assess whether this could be the case in kiwifruit, we conducted standardised observational surveys of insects visiting kiwifruit flowers within 31 orchards at three times: 10:00—11:00, 12:00—13:00 and 14:00—15:00 hr. Honey bees (Apis mellifera) represented 92% of visitations (n=5474), but temporal abundances were uneven (predicted abundances were lower at 14:00—15:00 hr). Predatory hover flies (Melangyna, Melonostoma, Allograpta spp.) also showed an uneven temporal pattern. There were no significant differences in the temporal abundances for buff-tailed bumble bees (Bombus terrestris), rat- tailed hover flies (Eristalis, Helophilus spp.), March flies (Dilophis nigrostigma), flower longhorn beetles (Zorion guttigerum) or the native bees (Leioproctus and Lasioglossum spp.) although, in some cases, low numbers may have masked potential unevenness trends. Variation in diurnal flower-visitation patterns among insects suggests the potential for complementarity between different pollinators.

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Managed bumble bees increase flower visitation but not fruit weight in polytunnel strawberry crops

Basic and Applied Ecology ◽

10.1016/j.baae.2018.05.008 ◽

2018 ◽

Vol 30 ◽

pp. 32-40 ◽

Cited By ~ 7

Author(s):

Alejandro Trillo ◽

José M. Herrera ◽

Montserrat Vilà

Keyword(s):

Fruit Weight ◽

Bumble Bees ◽

Flower Visitation

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Managed bumble bees are viable as pollinators in netted kiwifruit orchards

New Zealand Plant Protection ◽

10.30843/nzpp.2018.71.178 ◽

2018 ◽

Vol 71 ◽

pp. 214-220 ◽

Cited By ~ 1

Author(s):

Brian T. Cutting ◽

Lisa J. Evans ◽

Ludivine I. Paugam ◽

Heather M. McBrydie ◽

Linley K. Jesson ◽

...

Keyword(s):

Seed Set ◽

Bombus Terrestris ◽

Theoretical Calculations ◽

Predictive Modelling ◽

Bumble Bees ◽

Bumble Bee ◽

Bee Pollination ◽

Flower Visitation ◽

Stocking Rates ◽

Effective Pollinators

Protected cropping can increase orchard productivity; however, enclosed environments can be disruptive to pollinators. Bumble bees (Bombus terrestris) forage under covers, but industries lack guidelines for using them as pollinators. Here conservative stocking rates for bumble bees in covered kiwifruit orchards were identified using empirical manipulation of bee density and theoretical calculations based on bee behaviour. Bumble bee pollination at two bee densities (24 and 72 colonies/ha) was assessed within two fully netted sections (1/25 ha each) in a Gold3 kiwifruit orchard. Predictive modelling was used to estimate total bees required for pollination while actual pollination in the two blocks was measured directly. There was no difference in flower visitation rate between stocking densities but a 20% increase in seed set was found at high bee density. It was estimated that 90% of a Gold3 crop could be pollinated by 914 foraging bees/ha, or between 22 and 48 colonies/ha at the strengths used in this study. Bumble bees are effective pollinators in protected cropping environments and provide a viable tool for managed pollination under nets. A theoretical approach to refining stocking rates is a good option when manipulating pollinator densities is not possible.

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Floral Traits Predict Frequency of Defecation on Flowers by Foraging Bumble Bees

Journal of Insect Science ◽

10.1093/jisesa/iez091 ◽

2019 ◽

Vol 19 (5) ◽

Cited By ~ 3

Author(s):

Jonah M Bodden ◽

Jenny A Hazlehurst ◽

Erin E Wilson Rankin

Keyword(s):

Disease Transmission ◽

Bumble Bees ◽

Bombus Impatiens ◽

Floral Traits ◽

Potential Mechanism ◽

Large Area ◽

Fecal Matter ◽

Flower Shape ◽

Flight Cage ◽

Floral Visitors

Abstract Flowers may become inoculated with pathogens that can infect bees and other critical pollinators, but the mechanisms of inoculation remain unclear. During foraging, bees may regurgitate or defecate directly onto flower parts, which could inoculate flowers with pollinator pathogens and lead to subsequent disease transmission to floral visitors. We tested if captive eastern bumble bees (Bombus impatiens) (Cresson) (Hymenoptera: Apidae) defecate on floral surfaces during foraging and if flower shape played a role in the probability of defecation and the quantity of feces deposited on floral surfaces. Captive Bombus impatiens were fed a solution of fluorescent dye and sucrose, then allowed to forage freely on flowers of a variety of shapes in a flight cage. Flowers were then examined under ultraviolet light for fluorescing fecal matter. We found that bumble bees did defecate on floral surfaces during foraging and that composite flowers with a large area of disk flowers were the most likely to have feces on them. Our results point to defecation by bumble bees during foraging as a potential mechanism for inoculation of flowers with pollinator pathogens and suggest that flower shape could play a significant role in inoculation.

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