Entomology in the Arctic Tundra
The Canadian Entomologists’ latest issue is devoted to Arctic Entomology, with guest editors Derek Sikes and Toke T. Høye putting together an excellent suite of papers on this topic. This is a very timely issue – there is an incredible amount of Arctic entomology happening around the world, and the Arctic is an area that is undergoing rapid environmental change. It’s good that scientists are paying attention, and that entomologists are doing high quality research in the northern.
Deciding on an “editor’s pick” for this issue was difficult as there were many excellent papers to choose from. However, I ended up selecting Gergely Várkonyi and Tomas Roslin’s paper titled “Freezing cold yet diverse: dissecting a high-Arctic parasitoid community associated with Lepidoptera hosts”. These authors, from Finland, have presented a very nice study about some food-web dynamics occurring in Zackenberg, Greenland – a truly high Arctic field site, and one that has a remarkable history of long-term ecological monitoring. Their work is focused on unraveling some of the amazing interactions between Lepidoptera and their parasitoids, and this paper provides as “systematic effort to characterise the high-Arctic Hymenoptera and Diptera parasitoid community associated with Lepidoptera hosts”. This is a great paper, and hopefully continues to inspire continued efforts to study entomology at high latitudes.
I asked the authors some questions about their work and they kindly provided in-depth answers:
Q1: What inspired this work?
TOMAS: What got me interested in Arctic predator-prey dynamics was the work of my friend Olivier Gilg. His exploration of the predator-prey dynamics among collared lemmings and their few and selected enemies of Northeast Greenland made me realize that in a species-poor environment, the impact of individual species on each other will be oh-so-much easier to disentangle than among the zillions of interactions typical of tropical and even temperate communities. Here if anywhere you can actually work out both the structure and inner workings of full food webs – which is the very the idea that we have now realized in our study. (And well, from a less scientific point of view, after visiting Northeast Greenland I also realized that this is the most beautiful area of the globe, and that there is nowhere else that I would rather work.)
GERGELY: I have been interested in northern insects, especially hymenopteran parasitoids, since a very long time. I did my PhD in a subarctic environment in Finnish Lapland, with the main focus on host-parasitoid population dynamics between periodic moths and their enemies. I first encountered Greenlandic ichneumonids when my former teacher in ichneumonid taxonomy – and current friend – Reijo Jussila worked on the descriptions of some new species from the Scoresbysund area in Northeast Greenland. More than a decade later, Tomas asked me to identify some samples from Traill Island (NE Greenland), where he had initiated a pilot project on Lepidoptera-Hymenoptera food webs. The next step was when he invited me to join his project about to be launched at Zackenberg. The rest is history…
Q2: What do you hope will be the lasting impact of this paper?
TOMAS: What I hope that we have achieved are three things: to expose the importance of versatile biotic interactions even in a harsh arctic environment, to reveal the massive effort needed to convincingly dissect even a simple food web, and to establish the baseline structure of a food web facing imminent climate change.
GERGELY: Could not say it any better. I can only add that I hope our thorough overview of the taxonomy and natural history of individual parasitoid species will contribute to getting a better understanding of who is who and what roles each species play in this arctic scene.
Q3: Where will your next line of research on this topic take you?
TOMAS: While we have now figured out the structure of the Lepidoptera-parasitoid web, we should remember that this is but a small module of the overall food web of the region. Our current work aims at expanding/zooming out from this core web towards the full food web of the region, which should actually be more realistically doable here than anywhere else on the globe (se above). In this work, we try to make maximal use of modern molecular tools, offering new resolution to documenting trophic interactions.
GERGELY: Apart from the community ecology goals of this project, we will further continue to update what is known about the parasitic wasp fauna of Greenland. I am focusing on the Ichneumonidae, the single most species-rich family of Hymenoptera in both Greenland and the entire World. By combining morphology and molecular methods, I attempt to clarify species boundaries and detect potential cryptic species. The ultimate goal of this research is to compile a modern taxonomic overview of the Ichneumonidae of Greenland.
Q4: Any amusing anecdotes about this research?
TOMAS: Gergely used to wear a handy hiking suit of light coloration. One day he was almost shot as a polar bear after sneaking up on an unsuspecting colleague in the field.
GERGELY: Well, first of all I was not sneaking, just looking for adult wasps in a safe distance from this colleague of ours. She thought my net was a giant paw of a polar bear (!) and she was really scared for a short moment. But she was definitely not about to shoot me!