Curiosity, passion and science: On the natural history of an Arctic pseudoscorpion

I’m pleased to announce a publication about the natural history of a tiny, wonderful arachnid: the pseudoscorpion Wyochernes asiaticus.

The Arctic pseudoscorpion Wyochernes asiaticus (copyright C. Ernst, reproduced here with permission)

The Arctic pseudoscorpion Wyochernes asiaticus (photo by  C. Ernst, reproduced here with permission)

I’ve published quite a few papers, but this one is really special: it’s special because it’s about an obscure creature for which virtually *nothing* was known. It’s about a species with a fascinating distribution. To me, it’s an epic tale about a species that nobody really cares that much about. It’s special because it is research that was done just out of pure curiosity and fascination: there was no larger purpose, no great problem to solve, and no experiments to run*. It was based on observation and observation alone, and it was a long slog – done over many, many years (it took about 7-8 years to pull together this story, and this story is really only a prologue). Fundamentally this research was about trying to gather some base-line data about a small animal living in a big landscape.

The big landscape: A river above the Arctic circle: our pseudscorpion friend can be found under the rocks alongside this river.

The big landscape: A river above the Arctic circle: our pseudscorpion friend can be found under the rocks alongside this river.

This work presents some life-history data about a fascinating northern pseudoscorpion species, occurring only in the north-west of North America. As far as I know, it occurs only in regions that were primarily unglaciated during the last glaciation event which covered pretty much all of the northern half of the continent. However, unlike other Beringian species (e.g., the wooly mammoth), this little arachnid did not go extinct but rather continues to thrive in its somewhat unusual habitat under rocks, near rivers or streams.

After collecting and measuring nearly 600 specimens, I can now tell you a bit more about the species distribution in North America, and provide some insights into its life history traits. For example, larger females tended to have higher clutch sizes, a very common and well-known pattern with other arachnids, but there was certainly a paucity of data about this for pseudoscorpions. I also know that all its life stages can be collected in the Yukon in July, and that females can carry around quite a few young (over a dozen!).

But that’s about it. Beyond those fundamental life history measurements and comments on its distribution, the bulk of the species biology remains a mystery.

It may be possible to look at this work as a failure. Heck – a LOT of specimens were collected, by many, many enthusiastic helpers. It took some resources to get the work done (although it was mostly through stealth). A lot of time was spent at the microscope, and it certainly took a bit of time to pull together the paper. And what for? We still don’t know very much about the species: how does it disperse? How does it overwinter? How does it survive flooding of its habitat? How restrictive are the habitat affinities of the species? Do females and males tend to hang around the same rock, or do they mill about with others? What does it eat?

I don’t see this as frustrating, or discouraging, because it’s a start. Before thinking about bigger questions in ecology and evolution, your first need some basics. Only then is it possible to ask broader questions about, say, phylogeography, dispersal limitation, or behaviour.

I hope this work encourages others to seek out and discover new and interesting things about the unnoticed species that walk underfoot, live in tree-tops, swamps, or beneath park benches.

The Arctic pseudoscorpion, Wyochernes asiaticus

Another image of the Arctic pseudoscorpion, Wyochernes asiaticus taken during the 2015 field season

I was very pleased to publish this work in the Canadian Field-Naturalist. Sure, it’s not a ‘high impact’ journal, but it’s a rather special and unique journal for being an excellent location to publish work on the natural history of our species. I hope others consider this journal as an outlet for their curiosity-driven science. Over time, I hope the pendulum does swing, and as a scientific community we really embrace the value of “basic” natural history data. Without a fundamental working knowledge of our species we are hamstrung when it comes to solving the big environmental challenges facing our planet. It’s time to play catch-up. Let’s worry less about impact factors and show some love for smaller journals that are brave enough to keep on publishing about natural history. Let’s spend time observing our natural world, collecting interesting data just because.

I ended my paper with a paragraph about what it felt like to do this research. I am so thankful the editors allowed me to keep this paragraph. It’s important, and reflects my long-standing belief that the lines between a subjective love of nature, and objective observations about nature, should be blurred. They certainly are for me.

In conclusion, observing these marvelous animals in one of the most beautiful areas of the planet, was gratifying, awe-inspiring, and helped solidify a love of natural history. What has been learned is only the prologue to a truly astounding epic: many more discoveries await.


*Please check out this amazing blog post about the value of ‘observation’ to ecology. It relates closely to what I have written.

© C.M. Buddle (2015)

Landscape structure, insect herbivory, and ecosystem services

I’m pleased to announce a new publication to come out of the lab, with lead author Dorothy Maguire and co-authored by Elena Bennett and Patrick James. In this work, Dorothy ponders and writes about the broader implications of insect herbivory. More specifically, how insect herbivory is affected by landscape connectivity (i.e., the degree to which habitats are linked to each other), and how plant-feeding insects may relate to ecosystem services (i.e., the values and services that humans get from our natural systems).

Female (l) and male (r) Gypsy moth, caught in the act.

Important insects when, as caterpillars, eat a lot of foliate: Female (l) and male (r) Gypsy moth, caught in the act.

We certainly know that insects can do all kinds of damage to plants in ecosystems, but do insects in more (or less) connected habitats do more damage? To address this question Dorothy scoured the literature and got the relatively unsatisfactory answer of “sometimes”: 49% of the papers suggest increased connectivity relates to more insect herbivory and 28% of the papers show less herbivory in more connected patches. The lack of a clear answer actually makes quite a bit of sense since every context can be quite different, and not all insects are equal. It is hard to generalize since effects in forests will not be the same as in fields, and insects that are out-breaking (i.e., with major population explosions) may be affected differently than non out-breaking species. Dorothy certainly found these contexts were important. The results were important to illustrate how we need to adapt any management options with close attention to both landscape feature and their interaction with the life-history of the herbivore.

The second part of Dorothy’s work delved deeper into the literature to ask about the effects of out-breaking versus non out-breaking herbivore species on a select suite of forest ecosystem services: effects on timber production, aesthetics, soil formation and Carbon sequestration. There were some interesting results of this and again, any particular effect of herbivory on an ecosystem service was highly sensitive to the outbreak status of the herbivore. For example, the aesthetics of a forest can be positively affected by low levels of herbivory since this may help create pleasant conditions for light infiltration to the forest floor. However, an out-breaking species may defoliate a tree more completely, thus reducing the aesthetic value. Another example is that low levels of herbivory may positively affect timber production because trees may show “compensatory” growth after light feeding by an insect. In contrast, timber production will be negatively affected by high levels of defoliation as this may reduce a tree’s ability to grow. Although some of these results may seem rather logical, Dorothy’s work was unique as it showed how the scientific literature supports the connections between a herbivore’s life-history and key ecosystem services.

Screen Shot 2015-06-11 at 6.55.21 AM

Visual representations of the hypothesized relationships between insect herbivory and ecosystem services. Specifically (a) timber production, (b) aesthetic value of forests. Graphs are divided into four sections representing positive and negative effects of herbivory on ES, during non-outbreak (low) vs. outbreak (high) levels of herbivory. Quadrants are coloured differently based on the hypothesized strength of the effect of herbivory on ES: weak (light grey), moderate (dark grey) and strong (black). Proposed relationships are derived from synthesis of the available literature. From Maguire et al.

The last part of the work was focused on building a conceptual framework – a framework that ties together landscape structure, the process of herbivory, and ecosystem services. This is meant to be a road map for any stakeholders with an interest in any or all of those factors. For example, should a forest manager be tasked with understanding how to increase or support a particular ecosystem service, she or he needs also to recognize how that service is tied to important processes such as herbivory, and the related connections to the broader landscape.

Screen Shot 2015-06-11 at 7.05.34 AM

This work is novel and important because it links the well known process of insect herbivory to concepts of ecosystem services and to the discipline of landscape ecology. The marrying of these areas is critically important as we face increasing pressures on our natural systems, and the complexity of the systems can be overwhelming. We hope this work piques more interest in this topic, and that the framework Dorothy provides is useful to all the stakeholders.


Maguire, DY, PMA James, CM Buddle & EM Bennett Landscape connectivity and insect herbivory: A framework for understanding tradeoffs among ecosystem services. Global Ecology and Conservation. doi:10.1016/j.gecco.2015.05.006


Beetles from the North

I’m super-excited to announce new research from the lab, published yesterday with lead author Dr. Crystal Ernst.

Crystal’s paper focused on taxonomic and functional diversity of beetles across 12 sites in northern Canada, ranging from Labrador to the Yukon Territory, and from the bottom of James Bay all the way up to the tip of Ellesmere Island. This work is result of the Northern Biodiversity Program: a multi-institutional collaborative project about the ecological structure of northern Arthropods.

Crystal Ernst, on the tundra.

Crystal Ernst, on the tundra.

The paper was titled “Drivers and Patterns of Ground-Dwelling Beetle Biodiversity across Northern Canada” and in this research Crystal sorted and identified over 9,000 beetles from 464 species, and she classified the species by their functional ecology to assess how functional diversity may vary across the large spatial scale of this project. Instead of re-writing a summary here, I thought to use this blog post as an opportunity to reflect on what I see as the critical findings from this work, and why this is a paper that I’m incredible proud to be a part of.

  • To me, one of the more interesting findings of this work was that the functional diversity of beetles varied by latitude: although beetles do many things (e.g., herbivore, decomposers, carnivores), it doesn’t seem like all these functions happen at all latitudes. For example, although we document an impressive number of carnivores at all the sites, they are relatively more common in the more northern locations. This is a bit peculiar, and suggests that food-webs involving arthropods vary in some important ways depending on the biome. We also document that temperature is a major explanatory variable when considering functional diversity, which raises the important question about potential effects due to climate change. Indeed, should temperatures change in the north, this may affect the functional ecology of beetles, which in turn could affect other parts of the system.


Figure 1 from the paper: Fig 1. Map of the 12 study locations (North Pole Azimuthal projection), showing the spatial distribution of functional groups. These were pooled into trophic groups, and the pie charts show the proportion of the total site biomass represented by each trophic group

Figure 1 from the paper: Fig 1. Map of the 12 study locations, showing the spatial distribution of functional groups. These were pooled into trophic groups, and the pie charts show the proportion of the total site biomass represented by each trophic group

  • The research generally supported the well-known pattern in biogeography about how species richness decreases at more northern latitudes. When looking at which environmental variable may explain this pattern, temperature again came out on top. In other words, what beetles are found where is in part due to the temperatures in that region. Climate change scenarios therefore have significant potential effects on beetles in the north: beetles, like most other arthropods, are tightly linked to temperature. Even small changes in temperatures in the north may have big consequences for beetles.
  • One of the other big findings, to me, was the fundamental value of species-level data for an important taxa, across vast areas of Canada. Crystal recorded new Territorial and Provincial records for 15 beetle species, increasing knowledge about northern biodiversity. I’m also pleased that the data are fully available on-line, via Canadensys, so other researchers can access the information, re-analyze data, and benefit from and build upon this work.
  • The Arctic is special: it is a vast, cold, treeless landscape, with blankets of tundra, and permafrost underfoot. But it’s also special for beetles. After Crystal analyzed the community-level beetle data, using ordination methods, it became apparent that assemblages from the Arctic Islands of Canada were distinct from the sub-Arctic and north-Boreal sites. From a conservation perspective this is quite important. To some, the Arctic may come across as a big, ‘life-less’ region, with the odd polar bear roaming about, but in reality it hosts thousands of species, including hundreds of beetle species, and that beetle community is very different from what we find in other parts of North America. Special things deserve recognition and protection.
  • Every journalist I talked to has asked “Why beetles?” This is an easy one to answer: they fill virtually all roles in ecosystems, they are diverse, they are of interest to many people, and they are beautiful. The latter point is an important one, as it is important to capture curiosity and fascination about arthropods.


Carabus vietinghoffi. Photo by Henri Goulet.

A northern beetle: Carabus vietinghoffi. Photo by Henri Goulet.

In sum, this was a terrific project to be involved with, and our lab (and our collaborators) are thrilled that the efforts from the Northern Biodiversity program are showing up in the literature (for more examples, check out this, or this).

And rest assured, there’s more to come…

The effects of Twitter on student engagement and learning

There are lots of ‘feel good’ stories about using Twitter in teaching, and I’ve long been a supporting of using social media in undergraduate classes. But does it work…? What effects does Twitter have on learning?

An example of a student Tweet, used to promote their blog post.

An example of a student Tweet, used to promote their blog post.

This was a question we decided to tackle in my field biology class, and recently, in a collaboration with Lauren Soluk (as part of her graduate work), we surveyed students about using Twitter in the classroom*. Here are the take-home messages from the work:

  • Students Tweeted over 200% more than what was required as part of the course work
  • Students used Twitter in many different ways, from informal communication, to promoting their own blogs, to asking questions of each other or of the course instructors and TA.
  • Students used Twitter to communicate with their instructor or TA 56% of the time, with their peers 27% of the time, and with people external to the course 17% of the time.
  • 94% of students felt that among-group communication was beneficial (i.e., either ‘yes” or ‘somewhat’) to their learning, and 78% of students surveyed felt Twitter increased this among-group communication.
  • When asked whether Twitter had an impact on how they engaged with the course content, 67% of the students answered ‘yes’ or ‘somewhat’.
  • When asked whether Twitter is a good tool to help student learn in the classroom,  78% of the students answered ‘yes’ or ‘somewhat’.
A learning community: One student group Tweeting at another student group, to ask them a question.

A learning community: One student group Tweeting at another student group, to ask them a question.

Interesting, most students surveyed said they wouldn’t continue to use Twitter after the class was over. They certainly preferred other tools (e.g., Facebook) to Twitter. Despite this, the students felt Twitter useful in the context of the field biology class, and could see its value independent of their own personal views.

Overall, the results are impressive, and suggests there are good reasons to consider using social media tools such as Twitter, in a University class. It’s certainly not a tool for everyone (and there are important guidelines to consider), nor would it be useful in all contexts, but it clearly serves an important role in my field biology class. Twitter allows students to engage with different audiences, and helps create a rather novel learning community: a community that can include experts from around the world.

A question asked by students, over Twitter

A question asked by students, over Twitter

The answer... from an expert from a different country.

The answer… from an expert from a different country.


*Soluk, L & CM Buddle Tweets from the forest: using Twitter to increase student engagement in an undergraduate field biology course [v1; ref status: awaiting peer review]

Note: this paper is currently awaiting peer review – please consider reading the full paper and providing a review! 


Under the influence: how insecticides affect jumping spider personalities (Part 2)

This post is written by former PhD student Raphaël Royauté, and is a plain-language summary for our most recent article titled: Under the influence: sublethal exposure to an insecticide affects personality expression in a jumping spider

It’s well known that personalities can shift and change when we are ‘under the influence’ of chemicals, be it drugs or alcohol. As entomologists, we also consider this question for the insects and spiders that live among us: although we assume arthropods can similarly be affected by chemicals in their environment, it’s less clear how these chemicals may affect the personalities of these arthropods. We tested the effects of insecticide residues on the personalities of a jumping spider known to live in apple orchards. We found that individual-based personality shifts occurred when spiders were exposed to sub-lethal doses of an insecticide. This mean that even before we might see ‘population-level’ effects of insecticides on an important predator in agro-ecosystems, individual spiders themselves get, um, sort of messed up when under the influence.

How is this cute jumping sipder affected by insecticides? (photo by C. Ernst, reproduced here with permission)

How is this cute jumping sipder affected by insecticides? (photo by C. Ernst, reproduced here with permission)

Insecticides are often used in agriculture for various reasons, but can have negative effects on the ‘non-target’ fauna living in our agricultural fields. One of the most important challenges in evaluating their toxicity is that these chemicals can persist at low concentration in the environment. These concentrations are unlikely to kill exposed organisms but may substantially alter behaviours. Most of our evidence of the toxicity of insecticides on behaviours comes from studies on pollinators and research has shown decreases in spatial memory and learning capacities.

There remain gaps in our knowledge about how other types of organisms respond to these compounds. Studies on insecticide toxicity may be also limited because they tend to ignore how insecticides shape variation in behaviour. This is important because individuals differ in their behavioural tendencies and may not have the same weight in ecological processes: some individuals are more active, show more aggressiveness or consume more food. Personality traits can also be inter-related and form “behavioural syndromes”: clusters of behavioural traits that are correlated and evolve as a package. If personality traits are interconnected, any insecticide modifying one trait is likely to alter the whole syndrome. We’ve shown previously that behavioural syndromes differed between populations exposed and unexposed to insecticides in the Bronze Jumping Spider, a species common in apple orchards and known to prey on several economically important pests. But those populations could be different for a variety of reasons: for example, perhaps the insecticides affect spider behaviours because there is simply less food available in insecticide-exposed areas for example.

We wanted to test if insecticides could be directly responsible for the shifts in personality and behavioural syndromes we noticed. In other words, when a spider is “under the influence” of insecticides, is it still behaving according to its personality type?

The similarities between insecticides and drugs is fascinating: Both types of compounds target the nervous system, both can affect behaviours and both can kill above a certain lethal dose. In fact caffeine and nicotine evolved as natural plant defenses against insect herbivory and the latter was one of the first insecticides ever used. As crazy as it sounds, the effect of psychoactive drugs has been investigated in spiders in the past! The legend goes that, back in 1948, zoologist H. M. Peters was annoyed by his garden spiders spinning webs at “such ungodly hours” (2 am-5am). He wanted to found a compound that would shift the spinning behaviour to more a “decent” schedule, and he asked pharmacologist Peter N. Witt for help. Witt tried different psychoactive compounds on the spiders, including caffeine, LSD and marijuana but couldn’t produce the desired effect. What he found was in fact much more interesting: each compounds produced a distinct type of “drug web”, altering its shape, size or regularity ! (from Foelix’s “Biology of Spiders”) More recent research has shown that some commonly used insecticides affect web building in the same way drugs do.

We focused on how activity and prey capture capacities were affected by exposure to a widely used insecticide (phosmet) in the Bronze Jumping Spider. We tested activity and prey capture before and after exposure the insecticide and compared the amount of behavioural variation with that of a control group. Doing research in ecology sometimes requires using original equipment. In our case we found that the best way to expose our spiders to the insecticide was to use a hotdog warmer! We applied the insecticide solution on test tubes and used the rotation of the hotdog machine to get a homogeneous surface coated with dry insecticide residues. This allowed us to have a more precise control of the dose that each spider received while simulating field exposure conditions.

Unusual research equipment: hot-dog warmer.

Unusual research equipment: hot-dog warmer. (photo by R. Royaute)

One of our study spiders, in its tube. (Photo by R. Royaute)

One of our study spiders, in its tube. (Photo by R. Royaute)

We did not found any effect of the insecticide on average behaviour between treatments but the ranking of individuals was strongly affected after insecticide exposure. In general spiders exposed to the insecticide were more variable in their behavioural tendencies. This suggests that the effects of insecticides on personality differences may manifest before any effects on the population as a whole are detected, in which case scientists may be frequently underestimating the toxicity of insecticides. Another puzzling result was that males and females did not respond in the same way to insecticide exposure. Males were most affected in the way they explored their environment but their capacity to capture prey remained intact. Females instead showed a decrease in the strength of the activity-prey capture syndrome.

Spiders play an important role in agricultural fields as they help regulate pest outbreaks. By altering personality differences and their syndromes, insecticides may limit spiders’ capacity to provide this important ecosystem service in subtle ways. As usual, this research leads to more questions than answers. At the organism’s level, it is important to understand how long these personality shifts last for. Do these shifts vary depending on how frequently spiders get exposed to insecticide or to what types of insecticides they are exposed to? How do they ultimately affect a spider’s capacity to escape predators, capture prey or reproduce depending on the individual’s personality? At the ecosystem level, prey get exposed to insecticides too, what happens to the predator-prey dynamics when the personality of both prey and predator is affected? How does that translate into biocontrol services? These are all important questions that I hope to contribute to in the future. Stay tuned!

A male bronze jumper (Eris militaris). Photo by C. Ernst, reproduced here with permission.

A male bronze jumper (Eris militaris). Photo by C. Ernst, reproduced here with permission.


Royauté, R., CM Buddle & C. Vincent: Under the influence: sublethal exposure to an insecticide affects personality expression in a jumping spider. Functional Ecology. .

Godfray, H.C.J., T. Blacquiere, L.M. Field, R.S.Hails, G. Petrokofsky, S.G. Potts, N.E. Raine, A.J. Vanbergen & A.R. McLean. 2014. A restatement of the natural science evidence base concerning neonicotinoid insecticides and insect pollinators. Proc. R. Soc. B 281: 40558

Royaute, R., C.M. Buddle & C. Vincent. 2014. Interpopulation Variations in Behavioral Syndromes of a Jumping Spider from Insecticide-Treated and Insecticide-Free Orchards. Ethology. 120, 127-139.

Nathanson, J.A. 1984. Caffeine and related methylxanthines: possible naturally occurring pesticides. Science. 226, 184-187.

Rainer F. Foelix (2010). Biology of spiders. Oxford University Press. p. 179.

Samu & Vollrath. 1992. Spider orb web as bioassay for pesticide side effects. Entomologia Experimentalis et Applicata. 62, 117-124.

Trophic cascades in fragmented forests

Many birds eat insects and spiders. Some of these insects and spider are themselves predators, feeding on critters lower down in the food web. Some of the insects that are fed upon by birds, or other predators, also play important roles in forest, such as munching upon the fresh, green leaves of young trees (here’s a reminder).

Munch, munch, munch. The hungry caterpillar. (photo by Sean McCann, reproduced here with permission)

Munch, munch, munch. The hungry caterpillar. (photo by Sean McCann, reproduced here with permission)

These interactions are ongoing, all the time, in forests around the world. These forests, however, are changing in important ways. Some of them are getting smaller and smaller as humans continue to encroach on the land, via urbanization or agriculture. This results in a ‘fragmented’ landscape. A landscape with small forest patches, perhaps no bigger than your back yard. A landscape with larger forests, perhaps one in which you could get lost in. These forests are themselves connected to each other –sometimes directly by a corridor or hedgerow.

This is the context for PhD student Dorothy Maguire’s research. Within that context, Dorothy tackled a fascinating project, one that was just recently published. In this work, Dorothy and co-authors (including me, an undergrad at that time, Thomas Nicole, and McGill Professor Elena Bennett) put cages around small trees in different types of forests SW of Montreal. The cages (made of chicken wire) were in place to test the effects of ‘predator exclusions’ on the insects and spiders occurring on saplings. The prediction is that if you exclude larger predators, such as birds, this may allow a ‘release’ of other insects and spiders. In turn, this release may have trickle-down effects on an important process occurring in young trees: herbivory. For example, if a predator is more common because it’s not being eaten by birds, perhaps it will eat more caterpillars, which may mean the leaves on trees will be eaten less frequently. In ecology this is dubbed a ‘trophic cascade’. Dorothy did this work in the context of fragmented forests, and she worked in forests that were either small and isolated from other forests, or in forests that were large and connected to other forests. This was done because there’s an expectation that these ecological effects will be different depending on the degree of fragmentation happening on the landscape. For example, insectivorous birds may decrease in abundance in small, isolated patches, which means their effects on insect prey (and perhaps herbivory) may be reduced relative to effects in larger patches of forest.

Dorothy Maguire, working in a forest fragment.

Dorothy Maguire, working in a forest fragment.

During one summer field season, Dorothy and Thomas wrapped up some small sugar maple trees in chicken wire, left some alone as controls, counted insects and spiders over the summer months, and measured herbivory on the trees themselves. As expected, the effects of the ‘cage’ was significant: when you put a cage around a tree, you end up with more arthropods living on those trees. This confirms other papers which report a similar effect: insectivorous birds (and perhaps other vertebrate predators) have a significant, and meaningful impact on the insects and spiders living on trees. Or, stated another way, birds eat critters living on trees, and without these birds, there would certainly be more arthropods around!

Dorothy did not uncover a strong effect on the process of insect herbivory: although more insects and spiders were living in the trees protected by chicken wire, the leaves themselves were not affected. This could be because more insect predators were around, and thus compensating for the lack of birds, and eating just as many herbivorious insects (e.g., caterpillars) as the birds might have eaten.

The lanscape of southern Quebec. Lots of agriculture, some patches of forest.

The lanscape of southern Quebec. Lots of agriculture, some patches of forest.

Scaling up to the landscape context, there were no overall significant effects of the cage treatments in relation to the forest type, nor was the level of herbivory dependent on the landscape context. The general results for large, connected patches were no different than for small, isolated patches. However, the magnitude of the effect was marginally affected by the landscape context for the cage exclusion: vertebrate predator may have a more significant impact in smaller, isolated patches.

As with all research projects, this work resulted with as many questions as answers, which is equally frustrating and fascinating. It’s clear that vertebrate predators are important in these systems, but more work is needed to fully assess whether these effects are truly affected by the degree of forest fragmentation on the landscape. The lack of effects on the process of herbivory itself was equally intriguing – there are clearly many complex interactions occurring on small maple trees. Some of these interactions involve top-down predation events, but there are likely a suite of ‘bottom-up’ effects that are also influencing the system.


MAGUIRE, D. Y., NICOLE, T., BUDDLE, C. M. and BENNETT, E. M. (2014), Effect of fragmentation on predation pressure of insect herbivores in a north temperate deciduous forest ecosystem. Ecological Entomology. doi: 10.1111/een.12166

The effect of insecticides on jumping spider personalities

This post was written by C. Buddle and R. Royaute (a PhD student in the Arthropod Ecology lab).

We are pleased to announce a recent publication from our lab, titled Interpopulation variations in behavioral syndromes of a jumping spider from insecticide-treated and insecticide-free Orchards.  As is traditional in the lab, here’s a plain language summary of the work:

Agriculture has strongly intensified in the last 60 years, causing major concerns the sustainability of biodiversity. Agricultural practices can reduce habitats available for wildlife and also release toxins in the environment through the use of pesticides. Not all organisms living in agricultural fields are harmful, and many predators, including spiders, can help to reduce pest density. We have a relatively good knowledge that the diversity of spider species in agriculture, especially under our temperate latitudes, can help reduce pest damage. However, many of the factors that influence spider predation on pests depend on the outcome of behavioural interactions and we don’t know much about that topic. Spiders are often cannibalistic and aggressive with one another and these types of behaviours may limit their efficiency for pest control. We also need to understand if these aggressive tendencies vary depending on the type of agricultural field considered, a pesticide treated field may favour very different behaviours than one that is managed organically. Another important point is that populations are composed by a multitude of individuals, each with its own behavioural tendencies. Some individuals take more risks when confronted with predators (i.e. they are more bold), others are more active and explore larger areas or consume more prey. These tendencies – often referred to as personality traits – may also be correlated with one another.

In the context of agriculture, this may mean that certain individual spiders may contribute more to biocontrol because they consume more prey, or that certain individuals are more at risk of being in contact with pesticides because they are more active. To understand, how agricultural practices, and particularly insecticidal applications, affects personality and behavioural syndromes in spiders, we focused on the jumping spider Eris militaris, an abundant and charming jumping spider occurring in apple orchards in Quebec. Here’s a lovely photo from Crystal Ernst to illustrate how attractive they are: (thanks, Crystal, for permission to post the photo here!)

Screen Shot 2013-11-26 at 3.34.45 PM

We collected spiders from pesticide-treated and pesticide-free orchards, brought them back to the laboratory, and did a number of behavioural tests on the individuals from the two populations. Compared to the insecticide-free populations, we document that individuals from orchards that did receive insecticides experienced a shift in their behaviours syndromes. The overall shape of this syndrome is multidimensional, but it suffices to say that the correlations among different behaviours (the ‘syndromes’, otherwise known as the ‘personality’) differed depending on where the population came from.

A 'mirror test' - used to study behaviour in E. militaris (photo by R. Royaute)

A ‘mirror test’ – used to study behaviour in E. militaris (photo by R. Royaute)

In sum, the personality shifts that we documented for E. militaris are potentially quite important since the relationships between different behaviours may affect a spider’s ability to be an effective generalist predator in apple orchards. We need to consider how management  (including use of insecticides) may affect specific behaviours, and more importantly, the relationships between the different behaviours.


Royaute, R., C.M. Buddle & C. Vincent. 2013.  Interpopulation Variations in Behavioral Syndromes of a Jumping Spider from Insecticide-Treated and Insecticide-Free Orchards. Ethology. doi: 10.1111/eth.12185