Doctor Olivia Bernauer


Graduated PhD 2022

Thesis title

Native Pollinators in Australian Apple Orchards: Pollinator Efficiency, Foraging Behaviour, Phylogenetic Diversity of Functional Traits, and Natural History

Research Project

Pollination occurs when pollen grains are transferred from anther to stigma, fertilizing the flower’s ovaries. Some plants are wind pollinated, releasing pollen into the air to float to another flower, while others rely on animal-mediated pollination. Animal pollinators include insects, such as bees, beetles, flies, butterflies and moths, and vertebrates including some birds, lizards, and small mammals. The relationship between pollinators and plants is mutualistic: plants benefit from successful reproduction and pollinators benefit by obtaining resources like pollen or nectar.

Many animals may play a role in pollination, but because bees are one of the only major groups of insects that rely on pollen as their main form of protein, they have specialized adaptations to collect pollen and are often more efficient than other pollinators. The honey bee, Apis mellifera, is used around the world for the pollination and production of many major crops including almonds, blueberries, and watermelon. While honey bees are important crop pollinators, beekeeping has become increasingly difficult in recent years with the spread of new pests, parasites, and pathogens such as the introduction of the varroa mite (Varroa destructor) to new areas. Currently, there are no varroa mites in Australia, but the introduction of this destructive parasite is likely inevitable. To prepare for the introduction and spread of varroa mites and the damage they will do to the honey bee industry in Australia, new research has begun to focus on the potential for alternative pollinators, such as different species of managed pollinators or an increased reliance on wild, native pollinators.

My research aims to generate a more comprehensive understanding of apple and sweet cherry pollination in the lower Blue Mountains, Central West, and Southern Slopes regions of NSW, Australia. Specifically, my research focuses on alternative pollinators, examining pollinator foraging behaviour, pollinator effectiveness, pollinator phylogenetics and functional diversity, and the natural history of a native allodapine bee pollinator of apple and cherry.

This research will provide the first in-depth examination of apple and sweet cherry pollination in Australia and will begin to fill the existing knowledge gap on orchard pollination in Australia. My research will not only provide basic information on pollination, such as cataloguing which insect species are visiting crop flowers, but will provide detailed pictures of pollination services, within-orchard relationships and native bee biology in general.


Tierney SM, Bernauer OM, King L, Spooner-Hart R, Cook JM, (2023) 'Bee pollination services and the burden of biogeography', Proceedings of the Royal Society B: Biological Sciences, vol.290, no.2000, p. 20230747

Bernauer OM, Cook JM, Tierney SM, (2022) 'Division of foraging behaviour: Assessments of pollinator traits when visiting a model plant species', Animal Behaviour, vol.188, pp 169-179

Bernauer OM, Tierney SM, Cook JM, (2022) 'Efficiency and effectiveness of native bees and honey bees as pollinators of apples in New South Wales orchards', Agriculture, Ecosystems and Environment, vol.3371, Article no.108063

Nacko S, Hall M, Spooner-Hart R, Cook J, Bernauer O, Riegler M, (2022) 'Cucurbit crops in temperate Australia are visited more by native solitary bees than by stingless bees', Journal of Apicultural Research, vol.61, no.5, pp 675-687, Special Issue


Professor James Cook and Dr Simon Tierney