Spotlight on Research: Sarah Larragy

Tell us about the research you’re currently working on.

I am in my second year of my PhD in Maynooth University under the supervision of Dr James Carolan (Maynooth University) and Prof. Jane Stout (Trinity College Dublin) and supported by an IRC Government of Ireland Postgraduate Scholarship. My PhD research involves one of our most important native bumblebee species in Ireland, Bombus terrestris, otherwise known as the buff-tailed bumblebee.

These bumblebees are vital pollinators, and their effectiveness is reflected in their increasing popularity among horticultural growers. Bumblebees tend to forage during cooler, rainier and more typical Irish weather conditions, and they can buzz pollinate, which is important for crops such as tomatoes, blueberries and raspberries to produce fruit. Although these bumblebees already exist in the wild in Ireland, colonies are also produced commercially and imported.

The aim of my research is to understand buff-tailed bumblebees on both the molecular and ecological levels. First I conducted a large-scale genomic analysis of Irish buff-tailed bumblebees collected from many different sites across Ireland. With the results of this research, I will evaluate the genetic diversity within Irish populations and assess how these pollinators respond to threats such as parasites and pathogens. Finally, I will examine the capacities of these bumblebees to forage and pollinate crops and wild plants. We hope to identify what exactly distinguishes our bumblebees from those that we import, so we can better protect our native bumblebees from the many threats they face today.

For example, imported colonies pose threats of disease and potential cross-mating with native bees. Although guidelines and regulations relating to the import and use of commercially produced bees for the horticultural industry already exist, it was felt that these could be updated. In conjunction with the National Biodiversity Data Centre (NBDC) and the Department of Agriculture, Food & the Marine (DAFM), I was given an opportunity to develop new “Guidelines for users of imported bumblebee colonies”. These guidelines provide growers with advice and information on how best to use their colonies but also how to protect and utilise our native pollinators in the process. It is hugely rewarding for me as a scientist to be involved in research that can inform guidelines that are being passed directly into the hands of growers and the public. It is through this direct communication of research with the public that positive, evidence-based changes can be achieved.

What inspired you to pursue research in this area?

I have always had a huge interest in animals and biodiversity, which drove me to pursue a bachelor’s degree in Zoology in Trinity College Dublin. There, I learned about the importance of the natural world and how our society depends on healthy, functioning ecosystems. After my degree, I had an opportunity to do an internship in Dr James Carolan’s Applied Proteomics lab in Maynooth University. Dr Carolan’s research is focused on understanding how organisms interact with each other on a molecular level. Here I gained hands-on experience with bumblebees for the first time. I became fascinated with their behaviour, colony lifecycle, how important they are for ecosystem health and food production, and how these organisms work on a molecular level. In addition, witnessing the exciting and impactful research being carried out in Dr Carolan’s lab was immensely inspiring to me.

In your opinion, why is your research important?

It is our duty to understand and protect our native biodiversity. Pollinators are an extremely important and diverse group of animals that play a vital role in the pollination of many food crops as well as in the maintenance of healthy ecosystems and habitats. In Ireland alone, the economic value of pollination services is estimated at €59 million per year. However, our pollinators are in decline with one-third of our native bee species threatened with extinction.

We need to understand how various bumblebee species function on molecular and ecological levels to be able to protect them from the stressors causing their decline. It is also extremely important that genetic resources are evaluated so they can be identified and protected from hybridisation and/or genetic bottlenecks. Additionally, my research will provide data that will inform researchers, growers and policy makers alike on how to mitigate risks that imported bumblebees pose to native biodiversity.

What are some of the greatest challenges facing researchers in your field? What are the greatest opportunities?

Pursuing a PhD in pollinator research has provided me with fantastic opportunities. The recently established Irish Pollinator Research Network is continuously performing innovative research that has the potential to make a huge difference for pollinator health and wellbeing in Ireland. Connecting with researchers at other universities is highly motivating, as the network provides tremendous support and opportunities for collaboration in this field.

Pollinator research generates data that contributes to actions outlined in the National Biodiversity Database Centre’s All-Ireland Pollinator Plan, which aims to reverse the decline of pollinators in Ireland. My doctoral research gave me the opportunity to develop the “Guidelines for users of imported bumblebee colonies”, with the support of my supervisors and Una Fitzpatrick in the NBDC, to name a few.

Pollinator research often looks at areas in which there is the potential for a conflict of interest, e.g. agricultural land use and management. Additionally, ensuring that actions are taken and policy decisions are made based on research data can be a significant challenge too. Nevertheless, actions such as the development of the All-Ireland Pollinator Plan are resulting in growing and significant support among the public, the farming community and businesses alike.

How has the Irish Research Council supported you in your work?

It is very rare that you get an opportunity to design a PhD research proposal around a topic that really interests you. Irish Research Council funding has not only allowed me to progress to this next stage of my scientific and academic journey, but it also allows me to perform novel research in a field that is very exciting to me and to develop links with the DAFM, the NBDC, the All-Ireland Pollinator Plan, and outstanding researchers in the pollinator biology field in Ireland and abroad. I am very hopeful that my research findings will have a real and beneficial impact on the wellbeing of one of Ireland’s most important bumblebee species.