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Pollinator scientists gather at Trinity

Ireland’s pollinator research community came together this month to share their latest updates and research at the annual Irish Pollinator Research Network (IPRN) meeting. Researchers descended on the Botany building from Trinity, Maynooth University, UCD, Galway University, and Teagasc for the one-day meeting. Over the day, 15 talks were given, and a few of the highlights are presented below.

IPRN members at the 2024 meeting at Trinity College Dublin


Interesting cross-disciplinary research was presented by Engineer Adam Narbudowicz (Senior Research Fellow at Trinity), whose team, funded by Trinity’s Kinsella E3 multidisciplinary scheme and working with Jane Stout and Cian White, has been developing a small radar sensor capable of distinguishing between several pollinator species. This generated much excitement at the thought of how many different uses a technology like this could have.

Adam Narbudowicz presents work on radar sensors

Tara Dirilgen (Assistant Professor at Maynooth) presented a fascinating talk on why bee scientists need to diversify their pesticide research. With a systematic review methodology, she, and a team at UCD, found that bee researchers had overly invested in studying just one species, honeybees and just one group of pesticides, neonicotinoids.

In contrast, the conference had no such biases. There was a wonderfully diverse set of talks including research on solitary bee nesting habits (Colm O’Leary, a PhD student at UCD and Teagasc), rare and cryptic bumblebees (Lydia Thompson and Ciara Shivnen, PhD and undergraduate students at UCD), and cocoa pollination in Ghana (Richard Boakye, recent PhD student at UCD).

Richard Boakye presents his work from his PhD on implications of cocoa expansion in Ghana

Kate Harrington (PhD student at Trinity) presented some of the preliminary results from her survey of pollinators in newly planted Irish woodlands (part of the FOREST research project), and Sophia Couchman (PhD student at Maynooth) shared some of her findings about how pollinator abundance varies with the variable Irish summer weather.

Alexandra Valentine (PhD student at Galway) updated the meeting on her work on the Irish honeybee, and her work on morphological and molecular traits of Irish bees. Whilst Darren O’Connell (postdoc at UCD) presented a meta-analysis done as part of the National Apiculture Programme on the challenges associated with the treatment of Varroa using different methods. Julia Jones (Assistant Professor at UCD) presented findings from a study in the UK on non-native and native commercial bumblebee imports that demonstrated little introgression of non-native genes into wild populations. Julia announced that they have been awarded funding for the next phase of the National Apiculture Programme, and called for researchers to join their efforts.

Dara Stanley (Assistant Professor at UCD) did an excellent job of summarising the findings of three major research projects: PROTECTS, SusPoll and PoshBee, all of which examined the exposure and impacts of pesticides on pollinators. Some of the key findings were 1. The most widely used pesticides in Ireland are herbicides and fungicides; 2. There is little known about these products on bees; 3. Pesticide residues are found in crops, wild plants, and the pollen collected by bees; 4. Herbicides can influence molecular processes and functioning like digestion and learning in bumblebees; 5. Non-neonicotinoid insecticides can have sub-lethal impacts on pollen collection by bumblebee colonies and on solitary bees; and 6. Although Irish pollinators are most active in the middle of the day, we should think about mitigating pesticide use in a broader context than just spraying at different times.  

Dara Stanley summarising the pollinator-pesticide work from 3 recently completed collaborative research projects

Following this, Jess Knapp (Assistant Professor at Trinity) presented a major output from the PoshBee project, showing that despite strict risk assessment and regulatory process in Europe, pesticides are still having negative impacts on bumblebees, particularly in intensive agricultural landscapes. This research, which was the biggest standardised experiment ever performed on bumblebees, was recently presented to EFSA, the body that assesses pesticide risks and advises the European Commission, emphasising the importance of research for informing policy and regulation.  

In an exciting development for Irish pollinator research, Sarah Larragy (postdoc in Trinity) introduced the community to the new EU funded project, Restpoll. As Sarah explained, Restpoll is an EU wide project looking to understand how to restore habitats to help pollinators. The project kicked off at the end of 2023 in Sweden, so we’ll update you in future years on what they find.

Jane Stout (Professor in Trinity) closed out the conference with a discussion on translating research into impact. The group identified the stakeholders who should be informed by research, and the methods that are used for research dissemination. Challenges to bridging the gaps between research and practice/policy were discussed, and the Irish Pollinator Research Network as a whole was challenged to take our research out of the lab and into society, and to help each other to do that.

Jane Stout leading a discussion on engaged research for impact.

About the Author: Ed Straw is an IRC postdoc in Jane Stout’s research group at Trinity College Dublin.

World Bee Day – 20th May 2023

Did you know that there are more than 20,000 species of bee on the planet? And 100 different species just in Ireland? Did you know that only a few species live in social groups and make honey, that only female bees sting, and that stinging isn’t a fatal endeavour for most bee species?

When people think of bees, they tend to focus on honey, hives and stings, and various oft-quoted myths. They don’t realise that bees are a hugely diverse group of animals that have incredibly interesting lives.

Bees are a morphologically diverse group of insects – ranging from species that are a tiny ~2mm long, to species that are a massive 19x that size (about 38mm long). They are ecologically diverse too – some nest in the ground, others in holes in trees, and some even in the nests of other bees (these are called kleptoparasites, behaving in a similar way to cuckoo birds – killing the rightful occupants and laying their own eggs).

The one thing they virtually all have in common is that they need flowers to feed from – they get their energy and make honey from nectar, and get protein for growth and repair from pollen. Except ‘vulture bees’, which are a small group of closely related North American stingless bee species that feed on rotting meat. They use the meat as their protein source, but still make honey from nectar. So all bees need flowers to complete their live cycles (and, many flowers need bees too).

They are really an amazing group of insects, much more than just honey and hype.

And they have become cool. They adorn furnishings, clothing, crockery, water bottles – the list is endless. They typify pollinators – animals that move pollen between plants and enable seed and fruit production – and so are important to our agricultural system. And have become foci for conservation initiatives all over the world. They even have their own day in the year (20th May – World Bee Day).

But strangely enough, we don’t know everything there is to know about bees. Far from it. Most of what we know comes from a small handful of managed species – the honeybee, the buff-tailed bumblebee, the red mason bee. Even in Ireland, we don’t know nearly enough about most of our bees. When the most recent conservation assessment of Ireland’s bees was made in 2006, 16 species couldn’t be assigned a threat status because we didn’t know enough about them. Of the bees that we did know enough about, more than a third of them turned out to be threatened with extinction.

Want to learn more about Ireland’s bees? Have a go at our World Bee Day #BeeBingo, and look out for eight species active at the moment!

Since then, concerted efforts have been made to find out more about Ireland’s bees, and to protect them. Lots of research has been done (with eight PhDs completed on Irish bees in the past 12 months), and lots of practical conservation efforts undertaken, mostly under the auspices of the All-Ireland Pollinator Plan.

Trinity College Dublin has played a leading role in this. Professor Jane Stout in the School of Natural Sciences has been researching bees, their behaviour, and the causes and consequences of their decline for the past two decades. In this time, she and her research group have published dozens of scientific papers, and Prof. Stout co-founded the All-Ireland Pollinator Plan with Trinity alumnus, Dr Úna FitzPatrick at the National Biodiversity Data Centre. This has galvanised action the length and breadth of Ireland to protect and restore pollinators.

Trinity plays its part in a practical way too – the iconic lawns at the front gate have been transformed into ornamental meadows and low- and no-mow regimes have been implemented in other areas to allow wildflowers to flourish. Even in the city centre, both of these approaches can provide habitat for bees and other wildlife.

So this World Bee Day, take a closer look at these amazing insects, they are, of course, important pollinators, helping to maintain ecosystems and produce human food crops, but they are also fascinating and wonderful creatures in their own right.

About the author: Professor Jane Stout is Vice-President for Biodiversity and Climate Action at Trinity College Dublin, and has spent most of her professional career studying beestheir ecology, conservation and importance to people.

Bee Bingo for World Bee Day 2023

Did you know that there are more than 20,000 different species of bee worldwide and about 100 different species in Ireland alone?

To help raise awareness about some of our local species, post-doctoral researchers Alison O’Reilly and Cian White have developed a game… Bee Bingo. It’s easy to play – there are eight different bee species to spot (photos and information on all in the images below) – these bees are all out and about at this time of year, so find somewhere flowery, sheltered and take a closer look at the insects visiting the flowers – can you spot all eight?

If you do see them all, and reach a “full hive”, then share your accomplishments on social media #beebingo and tag us @CampusBuzzTCD.

Good luck and have fun!

Planning for a green future: How we can synergistically mitigate climate change and biodiversity loss

“Green future”, “Green initiatives”, “Green energy” – References to the colour green are impossible to avoid if we want to preserve, or even improve, the environment. It is clear that “going green” is in. However, there are many shades of green. There is the bright electric green commonly promised on renewable energy advertisements and infographics. There is also the deep forest green often pledged in biodiversity conservation campaigns. But, can we generate an environmental plan that actually delivers an appealing blend of both electric and deep forest green?

In our recent work, we set out to determine what the optimal shade of green for Ireland’s future is. Like many countries, Ireland recognises the need to urgently transition to a low-carbon economy to avoid the devastating impacts of unimpeded climate change. To meet our decarbonisation goals, Ireland has developed a Climate Action Plan1. The goal of the Climate Action Plan is to achieve a net zero carbon energy system for Irish society by 2050. Specific actions include increasing the amount of electricity generated from renewable sources from 30% to 80% by 2030, establishing 8,000 hectares of newly planted trees per year, and funding the restoration and rehabilitation of peatlands. So, the solution is quite straightforward— convert all current land uses to renewable energy infrastructure, new forests, and peatlands. Problem solved.

Not so fast. In addition to the climate crisis, we are also facing an equally urgent biodiversity crisis. These two green problems can’t be solved independently. The biodiversity and climate crises are entwined in a complex system of feedbacks, with biodiversity part of the Earth system regulating climate, and climate in turn determining biodiversity patterns and trajectories. Ireland is a trailblazer in acknowledging that a synergistic solution is needed, and in May 2019, became the 2nd country worldwide to declare a climate and biodiversity emergency (Dáil Éireann, 2019). However, recognising that climate and biodiversity require a coordinated response is only a first step. Implementation is going to be far more complicated. We need a plan, and we need it fast.

To come up with the plan that would be the best for both climate and biodiversity, we went through the major goals of the Climate Action Plan and reviewed the scientific literature to determine how to meet those objectives in the most biodiversity friendly way possible. We identified the major threats that climate actions, such as increased renewable energy infrastructure, could impose on biodiversity (Figure 1)2.

Fig 1. Mechanisms for climate actions which impact biodiversity. We outline major mechanisms that could impact biodiversity during the three primary life stages of renewable energy facilities: construction, operation, and decommissioning. From Gorman et al, 2023.

Along the way, we also found that many of the proposed climate actions can be implemented in ways that don’t harm biodiversity but actually promote biodiversity: our “win-wins”. For Ireland, these include increasing offshore wind capacity, rehabilitating natural areas surrounding onshore wind turbines, and limiting the development of solar photovoltaics to where humans have already erected structures, the so-called “built” environment.

Ultimately, biodiversity-friendly renewable energy can be achieved by prioritising renewables that are the least damaging and ensuring that infrastructure development is carried out as sensitively as possible to protect, restore, and enhance biodiversity. This could look different depending on where in the environment we are talking about, which is why choosing an appropriate site for each method is critical – we need a plan!

We hope that this work can form the basis for that plan for Ireland and stimulate broader discussions on what this looks like for other countries. By synergistically mitigating both our climate and biodiversity crises, we can ensure that Ireland’s future is Emerald Green.

About the author: Courtney Gorman is a postdoctoral researcher and project manager for the Nature+Energy project at Trinity College Dublin. She has a PhD in Biology from the University of Konstanz in Germany.

1.         Government of Ireland. Climate Action Plan. https://www.gov.ie/en/publication/ccb2e0-the-climate-action-plan-2019/ (2021).

2.         Gorman, C. E. et al. Reconciling climate action with the need for biodiversity protection, restoration and rehabilitation. Science of The Total Environment 857, 159316 (2023).

For The Love of Trees

Bringing together the disciplines of ecology, geography, economics, engineering and statistics, and funded by independent; philanthropists, Trinity’s FOREST project  aims to objectively explore the challenges, opportunities, and trade-offs involved in delivering a socially just, environmentally sustainable and financially viable afforestation programme in Ireland.  For my part, I am looking at some of the young native woodlands that have been planted over the past 20 years, with a view to understanding their ecological value and the ecosystem services they provide.  With these new native woodlands being promoted as a critical tool to address the joint crises of climate change and biodiversity loss in one shot – Are they living up to the hype?

With a total forest cover of 11% in Ireland only 2% is considered to meet the criteria for classification as native woodland, the rest comprising mixed or non-native forests the majority of which are fast-growing sitka spruce ‘tree farms’, loved by many foresters but fiercely opposed by others.  The legacy of past afforestation programmes have left us with these predominately single species forests, which provide benefits in terms of wood products and carbon sequestration.   Dense monocultures however have little benefit for biodiversity, are frequently a significant pressure on waterbodies, often produce wood of lower quality, and while forestry practices have evolved in recent years, for many sites, the carbon balance sheet might not look so rosy if past land use, drainage, and planting methods were to get factored in.   In this context, the planting of native woodlands for the multiple benefits they can provide, in addition to a longer term timber yield, has garnered increased attention.

An oak sapling in a woodland planted in 2009

As a starting point, I’ve spent the summer tramping around many of the sites planted with native trees under the Forest Services’ Native Woodland Scheme or similar planting approaches.  Aside from some ad hoc studies, there is little information on how these young woodlands are doing. Aware of some stories of failed young ‘tree cemetery’ woodlands, the increasingly obvious effects of ash dieback, and tales of success achieved through natural regeneration rather than planting, I was apprehensive about what I would find.

It’s hard not to feel humbled when you’re in the presence of a mature tree, a wonder of nature driving up from the earth over years with such singular life force, however a woodland or forest is so much more than just the trees. Can these young native plantations, typically planted in fields used previously for some form of agriculture, get to a point where the flora and fauna that characterise woodlands firstly find a way in, and then start to interact to deliver a dynamic woodland ecosystem? The more sites I walked through I found myself feeling that, given the right start, the trees know what to do. The youngest sites, full of baby trees often almost overtopped by an aggressive neighbourhood of grasses, look worryingly vulnerable.   Many of the owners and foresters I met talked sadly of losses during dry springs of recent years, a challenge that will no doubt increase with continued climate change.  In many sites the failed trees were dutifully replaced though, and the new forests got a second chance. 

Spot the trees – A woodland planted in 2020

Transformation starts after a few years as the trees develop.  These 5-10 year old sites were thrumming with wildlife, the abundance of bird, mammal and insect life particularly notable, with the increased shelter and structure provided by the young trees clearly providing roosting, foraging, resting and nesting areas.  They are not by any means a functioning woodland ecosystem, but their value for biodiversity is obvious.

After 10 years or so, depending on the site and trees planted, things generally start to look a lot more woodlandy.  The oldest sites I visited were planted 15-20 years ago, with tree canopies closing in, the ferns, bluebells, wood sorrel and mosses start to emerge.  I’m not sure whether these new arrivals were always there in the soil, biding their time, or find their way in, or a bit of both.   The sensory load that a woodland delivers is also palpable in the damp musty aroma, crunchy twigs underfoot, soft mossy surfaces and dappled light.   Decay, so crucial to a functioning woodland system, is clearly evident.   The owners of these sites are always thrilled telling me ‘you wouldn’t have believed it when it was planted, they were only knee high’.  I even found myself on one occasion not quite believing a site could have ever been a pasture field, and double-checking my information.  That said, just how woodsy the woodland has become varies between sites, and this might come down to factors such as how intensive former agriculture use was, whether the sites were wooded in the past or how close they are to other wooded areas.

The lost canopy  – An ash and oak woodland planted in 2008

Though overall pleasantly surprised at many sites, there were also young woodlands clearly battling for their lives.  Ash was planted in many native mixes before dieback hit.  Certain landowners, usually those with a good forester advising or with knowledge of trees themselves, were quick off the mark and had it out and replaced quickly.  In other sites, the owners have been watching the ash slowly die, frustrated and disheartened, but not quite sure what to do.  With the loss of ash, the way the site was planted matters to the outcome for the wood as a whole.  In a site where ash was put in rows with intervening oak, the effect of the dieback could be almost beneficial for the remaining oaks, like a managed thinning.  Where large blocks of ash were planted however, the woodland ecosystem that was establishing is effectively lost.

A large block of ash woodland planted in 2006,  but now lost to dieback.  An adjacent alder wood was thriving.

Deer in Wicklow seem to find their way into woodlands, despite the best efforts of those involved, with nibbled trees, particularly oak, faring poorly. The cost of fencing and tree-guards, and the ongoing monitoring required to ensure they remain effective, is an onerous commitment for both the forester and landowner.  You don’t need a research project to tell you that for these forests to survive in the longer-term, natural regeneration processes will need to be supported, and that won’t happen if deer aren’t controlled.  In many sites, oak trees were also clearly being affected by a powdery mildew, which though it doesn’t kill them can limit their growth.  In general, the oaks’ slower growth relative to other commonly planted species seems to stack the odds against it by just giving it more time in a vulnerable state for something to defeat it.  A lot of oak has been planted under the native woodland scheme.  It makes sense that that increasing the diversity of trees species planted wherever conditions allow would best buffer the future woodland against the risks of these multiple threats. 

Hope in an Acorn – In oak and scots pine woodland planted in 2007

Then there is the question as to whether woodland is the ‘best’ habitat for the land in question at all, the issue being that ‘best’ may be subjective.  A number of sites I visited where trees were faring well have equal potential to make nice grasslands if management were to be targeted at such.   Then there were several areas that were particularly damp or particularly dry and which, with trees dead or stunted, would appear to be intent on reverting to their former wetland or dry grassland habitat.

So, who are planting these sites and why?  It was a real highlight to get to meet and talk to the owners or foresters involved.  There were a definite cohort of owners planting for the love of native trees, with a view to enhancing biodiversity and potentially leaving a legacy for their families and for nature.  These owners often also had other areas of their land devoted to old woodlands, meadows, winter bird cover and natural regeneration, and usually had a walking trail through their woodland so they could savour it on demand.  Some had sought out the native woodland scheme despite their foresters and farming neighbours strongly advising against ‘wasting their good field’ on it.   Another broad grouping were the farmers who planted native woodland, often alongside other parcels of broadleaf or conifer plantations, on land that wasn’t of much benefit to them for farming anymore for one reason or another.  They were pleased to see it growing, and happy with a payment for land which was sometimes their ‘bad field’ and a burden.  They often admitted to not having step foot in their woodland for years.  There were also a few sites where the contact person was a manager of a larger landholding, having little knowledge of the woodland or who planted it, and in once case not aware it existed. 

A woodland planted in 2013 – now at an excellent height for its branches to slap you in the face repeatedly

The question gets asked whether planting should really have a role at all in the establishment of native woodlands.  With nursery stock of varying quality, potentially harbouring pathogens, and the challenges of a changing climate, could our native woodland establishment approach fail in the long-term?  Many argue that with patience, natural regeneration will deliver better and more resilient woodlands for us.  Allowing woodland vegetation to regenerate naturally serves as a foundation for ‘rewilding’, a loosely defined concept, but one that at its core involves the restoration of food webs and the recovery of ecological processes.  Of course, even such rewilded forests will need some level of ongoing intervention, as the diseases, deer and invasive plants that have found fertile ground in the remains of our crumbling natural ecosystem will otherwise scupper the best laid plans. As a farming nation we long ago lost the skills associated with a culture of having working woodlands within the farm setting, and so any broad scale woodland establishment within our farmed landscape is a hard sell even if the landuse policies shift to facilitate it, but this is particularly so for natural regeneration approaches given perceptions associating it with land abandonment. 

A small but passionate group of foresters are strong advocates for the native woodland scheme.  The management of planted native woodlands, particularly if close-to-nature practices are employed as they age, really draw on a foresters expertise and deep knowledge of trees and the environment.  Ultimately native woodland scheme sites,  when planted appropriately and with oversight of skilled foresters, do appear to provide a starting framework for a woodland which will, hopefully, also support natural regeneration as it ages to help sustain it in the long term.

It’s easy for the debate to get polarised, with proponents of rewilding often pitted against those in favour of a continued focus on non-native monocultures to support the timber industry.  If we are to treat these climate and biodiversity crises with the urgency they deserve, we need all options available, as it seems our best chance of success lies with embracing diverse forests, both native and non-native, both planted and naturally regenerated, but all delivering multiple benefits for climate and biodiversity.   

Kate (last on the right) pictured with the rest of the FOREST project team.

About the Author:

Kate is an Ecologist, nature-lover and PhD student based in the Dept of Botany, Trinity College.  She is 1 year into her PhD research being completed as part of the FOREST project and supervised by Jane Stout and Fraser Mitchell.