Nouvelles
The following is a guest post from ESC student member Sharleen Balogh. Sharleen is a Masters student at the University of Northern British Columbia (UNBC) working with Dezene Huber and Staffan Lindgren on Warren Root Collar Weevils. She recently took home a President’s Prize for best talk at the ESC/ESS JAM in Saskatoon.
For the past two years, I have been studying the Warren root collar weevil (Hylobius warreni). These weevils are fairly large and long-‐lived (for insects anyways, they are about 12-‐15 mm, and live for up to five years). I think they are big enough to have distinct faces and personalities, although some people have told me that I’m personifying them just a bit too much and I need to take a step back from my work, but that’s another story altogether.
I am studying them because of their effects on coniferous trees, especially young lodgepole pines regenerating after the mountain pine beetle infestation in the interior of British Columbia. The larvae feed on the roots and root collars of trees, causing mortality of young trees and growth reductions in older trees (Cerezke 1994). They are native to the Prince George area (where I am doing my research) and can be found across much of Canada. They are often fairly common within their range. However they really can be described as “everywhere and nowhere”, since you can find them in almost any forested area in the region, just in low numbers and often well-‐hidden.
The Warren root collar weevil. How can you not love that face? Photo: Staffan Lindgren
I have specifically been looking at the mechanisms by which they locate their host trees. The weevils can’t fly, so they walk along the ground in search of hosts. We know that they use vision (Machial et al. 2012a) to locate trees, but not much else about their host location. There are higher rates of attack by larvae on larger trees, but this could just be a result of a larger area of roots available, not an actual preference when finding hosts. So far no one has been able to find any chemical cues that they use, although this is very unusual for an insect. Some evidence suggests that at least in some situations their movements may be predominantly random and non-‐directional (Machial et al. 2012b, Klingenberg et al. 2010).
In order to study them, I decided to track the weevils using harmonic radar technology. This is the same technology that is used to locate avalanche victims. It functions by the detector sending out a signal in the microwave range that is passively reflected back by a transponder, attached to whatever you want to find. For use in locating avalanche victims, the transponder is the large Recco® tags you often see in ski jackets. In the case of the weevils, I used a miniaturized transponder– a tiny diode soldered to a 4 cm long piece of copper wire.
When I first decided to use this method, and to construct the transponders myself, I went online to learn how to solder. I was told by several different tutorials that it is “very easy, almost impossible to get wrong”. This may be the case when soldering computer circuit boards, but not so when soldering two tiny pieces of metal together under the microscope. In the end though, I did get it to work, and I tagged 115 weevils over two field seasons. I released them into individual plots in a lodgepole pine stand, within which I had mapped all of the trees, and I relocated them at regular intervals.
Although I’m still analyzing my data, my results suggest that the weevils preferred to go to closer trees, larger trees, and that the preference for larger trees increases when the trees are further away. Otherwise, their movements appear to be primarily random and non-‐directional. So, as strange as it is, maybe they do just use vision and random movements. If this is true, and their host selection process is predominantly random, this may have implications for forest management. It might make finding ways to limit their spread into new stands difficult, and it may make it difficult or impossible to identify potential genetically resistant trees for planting.
Warren root collar weevil tagged with transponder. Photo: Staffan Lindgren
References Cited:
The following post is by Chloe Gerak, a Masters student at UBC who completed an undergraduate project at Simon Fraser University in the Gries lab.This past weekend, she won the top prize for an undergraduate talk at the Annual General Meeting of the Entomological Society of British Columbia with a talk entitled « How the false widow finds true love ». Photos by Sean McCann.
A male Steatoda grossa. These spiders have stereotyped courtship behaviour involving stridulation of an organ located dorsally between the cephalothorax and abdomen.
For approximately eight months, I studied the courtship behaviour and chemical communication between male and female false widow spiders, Steatoda grossa. Prior to studying them in Prof. Gerhard Gries’ lab at Simon Fraser University, I had never even heard of this species!
Female Steatoda grossa on her web.
My mentor Catherine Scott and I had collected juvenile and mature false widow spiders around the basement of the biology wing at SFU… and let’s just say we didn’t have a lack of specimens to collect. Almost every baseboard we turned over or corner we searched, we would find these little guys and collect them individually into petri dishes. These formed the nucleus of our laboratory colony which we reared for behavioural experiments.
A common nickname for Steatoda grossa is the “cupboard spider,” which I find extremely appropriate considering these spiders seem to love dwelling in dark corners. Since they are so abundant around SFU, and I had never even seen one before this, I think people should not be frightened by cohabiting with them… likely, you won’t even know they are there!
The following post comes to us from our new President, Staffan Lindgren, who in addition to being a great researcher, takes the time to make natural history observations which are crucial for any entomologist.
Male Vespula pensylvanica. This was the male that was mating with the queen.
On occasion I grab my camera and go out in the garden to see if some photogenic insect or other arthropod is willing to pose for me. On October 18, I went out to see what was happening around the rose bushes between ours and our neighbour’s yard. I was immediately struck by the fairly intense activity of yellowjackets, which peaked my curiosity. After looking around for a while I saw what the commotion was all about; a large queen was being mobbed by a number of males. To my knowledge, I have never seen a male yellowjacket wasp before. A casual observer would just think that they were workers, since they are about the same size and don’t otherwise look obviously different. Looking closer I realized that the queen was in copula with one of the males, so I tried to get some photos. It immediately became clear that I had the wrong lens on; my Canon MP-E 65 macro simply couldn’t capture the entire scene. Therefore the photos I managed to take only show parts of the scene. I didn’t have time to go back and change the lens, unfortunately, but below are a few shots.
Here is another view of the male.
This is the queen. The male she was mating with is in the lower right corner. Note the second male trying to mate with her in the background. Note also that her legs are not in contact with the leaf; she was essentially held by the male.
And here is a view of the act of mating, showing the male in the foreground holding on to the queen. Using these photos and the identification guide to the Vespinae I came to the conclusion that these are Vespula pensylvanica Saussure.
Sarah Loboda of McGill University, a double runner-up! Photo by Miles Zhang.
In my last post, I shared some thoughts about the value of the President’s Prize at Annual Meetings of the Entomological Society of Canada. This time, with the help of Tyler Wist, I present the names and categories for each of the winners and runners-up.
I would like to congratulate all of these fine scientists, and invite each of them to share a bit about their work here on the ESC blog.
Oral Presentations
Bees and Pollination
Winner:
Veronika Lambinet (Simon Fraser University), with M. Bieri, M. Hayden, and G. Gries.
Bee talk – Do honeybees use the earth’s magnetic field as a reference to align their waggle dance?
Honourable mention:
Danae Frier (University of Regina), with C. Sheffield.
Bumblebees do it better: the importance of native bees to the pollination of haskap crops.
Biodiversity and Conservation
Winner:
Sebastian Ibarra (Simon Fraser University), with S. McCann, R. Gries, H. Zhai, and G. Gries.
The wrath of the bald-faced hornet – pheromone-mediated nest defence.
Honourable mention:
Seung-Il Lee (University of Alberta), with J. Spence and D. Langor.
Variable retention harvesting and saproxylic beetle conservation in white spruce stands of the boreal ecosystem.
Sarah Loboda (McGill University), with J. Savage, T. Hoye, and C. Buddle.
Ecological and evolutionary responses of Arctic flies to recent climate change in Zackenberg, Greenland.
Arthropod Biology
Winner:
Sharleen Balogh (University of Northern British Columbia), with D. Huber and S. Lindgren.
Host selection of lodgepole pine (Pinus contorta) by the Warren root collar weevil (Hylobius warreni).
Honourable mention:
Aldo Rios (University of Manitoba), with A. Costamagna.
Contribution of soybean aphid alates to colony fitness under predation.
Pest Management
Winner:
Tina Dancau (CABI, Switzerland), with T. Haye, P. Mason, and D. Gillespie.
Mortality factors affecting the diamondback moth (Plutella xylostella) in continental Europe: a preliminary life table analysis.
Honourable mention:
Jon Williams (University of Guelph), with H. Earl and R. Hallett.
Laboratory investigations of swede midge, Contarinia nasturtii, oviposition and damage symptoms to canola.
Posters
Winner:
Sabrina Rochefort (McGill University), with T. Wheeler.
Taxonomy and diversity of Parapiophila (Diptera: Piophilidae).
Honourable mention:
Sarah Loboda (McGill University), with C. Ernst and C. Buddle.
Yellow pan traps versus pitfall traps: best monitoring tool for ground-dwelling arthropods in the Arctic.
Sabrina Rochefort – winner of the President’s Prize for best poster
At the recent ESC/ESS JAM in Saskatoon, not only were we treated to some great science and camaraderie, but the beloved institution of the President’s Prize sessions for student talks and posters provided some of the most stimulating and exciting times. This was my first year not being in the competition, and I would like to offer my views on the subject.
1) The President’s Prize encourages excellence: Students are definitely motivated to deliver polished and professional presentations in the hopes that their efforts will be recognized publicly. This reaches further than the conference, to encourage students to vet their talks and posters within their laboratories and departments in formal and informal settings in order to make the best presentation possible. This can only be a good thing.
2) The recognition is important: this prize, although modest financially, has amazing value as something to put on one’s CV. This enhances the career prospects of the winners and also the recognition that conference travel for students is worth funding within departments. Again, the value of this prize reaches much further than the conference, as students returning with the tangible benefits of a prize winning talk encourages others to make it a priority to attend and give an excellent talk next year.
The President’s Prize and the more recent innovation of the Graduate Student Showcase are thus valuable to the society as a whole. By encouraging and recognizing the efforts of students who attend our conferences to present well-polished research results, we promote excellence in scientific communication. We can all learn from the skill and innovation of these students!
With all of this in mind, I would like to make some recommendations:
1) For every conference, pre-publish the scoring rubric to be used by the judges. This will ensure that students entering a talk or poster know what points they have to hit to make their talk a candidate for the prize. These rubrics should not penalize creativity on the part of the students or discretion on the part of the judges, but should ensure that there is a baseline for what is expected.
2) At every conference, formally recognize runners-up in every session: It costs nothing but a bit of extra time during award presentation, but the chance to bestow recognition on a few more students should not go to waste. Many sessions have many excellent talks, and to send an excellent presenter home with nothing does no one any good. It has been a bit hit and miss in recent years at ESC meetings with regards to runners-up, and I think it should be the case that every conference includes this important recognition.
3) Send all competitors home with the judging sheets. This is a bit more onerous on the part of the judges, but the judges can definitely jot down some notes on their scoring sheet and show the tally for how well the talk lived up to the rubric. This is important to show that the criteria used to score the talks informed the decision. More importantly, it allows students to see how well their talk met the judges’ expectations, and to improve their presentations for the next year. This has been done at a couple of ESC meetings over the last few years and as far as I know, students found the feedback they got very valuable and were able to use it to improve their science communication skills.
Thanks to Mile Zhang for photos of the poster competitors, and to Catherine Scott for helpful suggestions. Congratulations to all this year’s winners, runners-up, and competitors!
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