Insect herbivory in fragmented forests: it’s complicated

I’m excited to announce a recent paper to come out of the lab, by former PhD student Dorothy Maguire, and with Dr. Elena Bennett. In this work, we studied the amount of insect herbivory in forest patches in southern Quebec: the patches themselves varied by degree of fragmentation (ie, small versus large patches) and by connectivity (ie, isolated patches, or connected to other forest patches). We studied herbivory on sugar maple trees, both in the understory and canopy, and at the edges of the patches. Our research is framed in the context of “ecosystem services” given that leaf damage by insects is a key ecological process in deciduous forests, and can affect the broader services that forest patches provide, from supporting biodiversity through to aesthetic value. Dorothy’s research was part of a larger project about ecosystem services and management in the Montérégie region of Quebec.

 

Maguire_Canopy.JPG

Dorothy Maguire sampling insects in the tree canopy (Photo by Alex Tran)

The work was tremendously demanding, as Dorothy had to select sites, and within each site sample herbivory at multiple locations, including the forest canopy (done with the “single rope technique). Dorothy returned to sites many times over the entire summer to be able to assess trends over time. Herbivory itself was estimated as damage to leaves, so after the field season was completed, thousands of leaves were assessed for damage. The entire process was repeated over two years. Yup: doing a PhD requires a suite of skills in the field and lab, and there is no shortage of mind-numbing work… Dedication is key!

As with most research, we had high hopes that the results would be clear, convincing, and support our initial predictions – we certainly expected that forest fragmentation and isolation in our study landscape would have a strong effect on herbivory – after all, our study forests varied dramatically in size and isolation, and herbivory is a common and important ecological process, and insect herbivores are known (from the literature) to be affected by fragmentation.

 

QuebecLandscape

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

 

However, as with so much of ecological research, the results were not straightforward! “It’s complicated” become part of the message: patterns in herbivory were not consistent across years, and there were interactions between some of the landscape features and location within each patch. For example, canopies showed lower levels of herbivory compared to the understory, but only in isolated patches, and only in one of the study years! We also found that edges had less herbivory in connected patches, but only in the first year of the study. Herbivory also increased as the season progressed, which certainly makes biological sense.

So yes, it’s complicated. At first glance, the results may appear somewhat underwhelming, and the lack of a strong signal could be viewed as disappointing. However, we see it differently: we see it as more evidence that “context matters” a great deal in ecology. It’s important not to generalize about insect herbivory based on sampling a single season, or in only one part of a forest fragment. The story of insect herbivory in forest fragments can only be told if researchers look up to the canopy and out to the edges; the story is incomplete when viewed over a narrow time window. In the broader context of forest management and ecosystem services, we certainly have evidence to support the notion that herbivory is affected by the configuration of the landscape. But, when thinking about spatial scale and ecosystem processes, careful attention to patterns these processes “within” forest patches is certainly required.

We hope this work will inspire others to think a little differently about insect herbivory in forest fragments. Dorothy’s hard work certainly paid off, and although the story is complicated, it’s also immensely informative and interesting, and sheds light on how big landscapes relate to small insects eating sugar maple leaves.

Reference:

Maguire et al. 2016: Within and among patch variability in patterns of insect herbivory across a fragmented forest landscape. PlosOne DOI: 10.1371/journal.pone.0150843

 

Advertisement

SciArt and SciComm at an entomology conference

Earlier this week I had the pleasure of attending the Entomological Society of Canada’s annual conference, held in Montreal. As usual, it was awesome: it was great to catch up with fiends and colleagues, and to hear about some amazing insect science. There was an active hashtag, too, that you can check it to get a sense of the breadth and depth of entomology in Canada.

A real highlight for me were the amazing conference notes that were sketched by the superbly talented Paul Manning*. I’ve certainly heard of this idea before, and read about how visual note-taking at a conference can provide new insights into the science, and enrich the experience, especially when shared with others. However, seeing this in action was quite special, and I was impressed with how Paul was able to grasp the fundamentals of talks, and draw out the key points. Case in point, check out this sketch of May Berenbaum’s talk on honey bees:

Capture

Here’s another example, based on a talk about wasp (Vespula) alarm pheromones, by Sean McCann. Here, Paul guides us through the talk, by using simple arrows, but also uses different coloured boxes to illustrate the ‘introduction’ compared to the ‘methods and results’. The take-home messages are super-clear!

Capture

And I am immensely grateful to Paul for doing  a visual sketch of my own talk, about the functional and taxonomic diversity of northern arthropods. It was a dense talk, and covered a range of topics, from ecological monitoring to complex measures used to evaluate functional diversity. Paul captured it very well, and was able to effectively get the main message of the presentation.

Capture

In sum, THANK YOU, Paul, for doing this, and illustrating the different ways we think about, draw about, and communicate science, and showing how visual note-taking has immense value. I can imagine Paul will remember those talks long into the future, and he has a permanent record to show for it. Although I dabble in sketching here and there, I’ve yet to give this a try at a scientific conference. I think I ought to bring a sketchbook to my next conference: I’m inspired.

—-

*you can check out more of Paul’s great work on his blog.

Vouchers? What vouchers? Revealing a crisis in arthropod-based research

Here’s a hypothetical scenario:

Q: “Hey I see you published a paper that shows the wolf spider Trochosa ruricola occurs up in the Ottawa Valley – I didn’t realize it had reached that far. It’s an invasive species, so tracking its distribution is quite important

A: “Yeah, we too were surprised it was up that far: to our knowledge, only Trochosa terricola was in that part of Ontario

Q: “It is tricky to tell apart those two species! What museum did you deposit specimens in? I’d like to take a look at them to verify the identification.

A: “Um, we didn’t get around to depositing specimens in the museum. There might still be some in the lab. I’ll have to get back to you...”

Not cool.  And also much too common.

Bottom line: when specimen-based research is done with arthropods, whether it is a biodiversity inventory, a community ecology study, or a taxonomic revision, the researchers must deposit voucher specimens in a research museum or institutional collection. This is only way to truly verify that the work is accurate, that people are calling things by the same name, and it puts a stamp in time for the research. Without deposition of these voucher specimens (somewhere that is publicly accessible and curated, and along with data about time, place and collector) the research cannot be verified, and this goes against the principle of repeatability in science.

Beetles in drawers: a great example of specimens in a curated museum, and shows how such specimens can be used for all kind of research!

Beetles in drawers: a great example of specimens in a curated museum, and shows how such specimens can be used for all kind of research!

This is a no-brainer, right? It’s time to test whether or not scientists actually bother to deposit voucher specimens…. As part of a graduate-level* class in Entomology last winter, we surveyed the literature to find out the frequency of voucher deposition with arthropod-based research. We looked at papers to see what percentage actually report on vouchers, assessed whether the frequency of voucher deposition varied by research type, study organisms, institution (of researcher), and whether voucher deposition has changed over time.

We published the results a few weeks ago, in the Open Access journal PeerJ, and our work has revealed a crisis in arthropod-based research. Overall, rates of voucher specimen deposition were very low, as only 25% of papers report on the deposition of voucher specimens. This is horrible, and essentially means that the specimens from the majority of papers published cannot be traced to a collection, and cannot be verified.

Some disciplines were worse than others, as crustacean researchers deposited vouchers only 6% of the time, as compared to the relatively higher rate of voucher deposition by entomologists, at 46%. Here is a summary of the main findings:

The main findings of our research: the asterisk illustrates a significant difference relative to a global mean.

The main findings of our research: the asterisk illustrates a significant difference relative to a global mean. Figure from our paper, published here.

Is there any good news? Perhaps so… when looking at rate of voucher deposition over time, more papers are reporting about vouchers in 2014 (35%) compared to 1989 (below 5%).

At the end of our paper we provide some conclusions and recommendations, and these are repeated here:

  1. PIs must be responsible and proactive on the process of voucher specimen deposition, from the start of any project.
  2. Graduate students need to be mentored appropriately about the importance of voucher specimen deposition.
  3. It needs to be recognized that voucher specimens are important for all branches of arthropod research – there is no reason that entomologists should do better than, say, crustacean biologists.
  4. Close collaboration between Universities/Research Centres and Museums is required, so that there is an agreed up, and easy process for all researchers to deposit vouchers.
  5. Everyone involved with arthropod-based research needs to work together to push for long-term, sustainable funding for institutional collections/museums so that proper curation of vouchers can be done.
  6. Publishers and editorial boards need to have clear policies about voucher specimens, so that any papers published are required to report on vouchers.

I recognize that the title of this post is provocative. Is it *really* a crisis?

I think it is: I think that even the best rate of voucher deposition that we report on is too low. We must aim to be closer to 100%. It’s important as we work to describe the world’s biodiversity, understand what is happening to our species in the face of climate change, or track the distribution of invasive species. It’s important that our hard work is more than a publication: our hard work is often a specimen, and that specimen needs to be accessible for future generations.

Voucher for critters than need to be stored in liquids looks something like this.

Voucher for critters than need to be stored in liquids looks something like this.

Reference:

Turney S, Cameron ER, Cloutier CA, Buddle CM. (2015) Non-repeatable science: assessing the frequency of voucher specimen deposition reveals that most arthropod research cannot be verified. PeerJ 3:e1168 https://dx.doi.org/10.7717/peerj.1168

* A most sincere thanks to my graduate students Shaun, Elyssa and Chris – these students did the lion’s share of this project, and took on this graduate class with great enthusiasm, maturity and motivation. You all inspire me!

It started with the crickets

It all started with the crickets.

And it got a lot bigger than that.

I couple of weeks ago I received a gift from one of my MSc students – a lovely little tarantula that we affectionately call “Shelob”. My family was reasonably tolerant of this new addition. Shelob is a Chilean Rose-hair, a sort of pet that is sometimes referred to as a pet rock. But it’s a rock that needs feeding, hence the crickets. “Feeder crickets” are crafty little insects and despite my assumption that the terrarium for the crickets was sealed tightly, that was not the case. Unfortunately we had guests over for the weekend, and they were unimpressed by the cheeping crickets from under their bed in the middle of the night. And my teenage son was very angry one morning, having been woken up a bit too early by crickets in his bedroom*. The crickets were everywhere:

 

Crickets: Everywhere

Crickets: Everywhere

 

I'm not the only one with a cricket problem.

I’m not the only one with a cricket problem.

Living with an Entomologist (or Arachnologist) can be a challenge. It requires our partners / families / roommates / friends to be very tolerant of some odd behaviours. In my experience entomologists really know how to bring their work home with them. Our field of study is a passion that moves beyond the research lab or field site. It’s a passion that means we need to have sweep nets at home as well as at work, and most entomologists I know have a vial (or two) in their pocket, so they can collect their study specimens wherever they are (although we sometimes forget). This means, by extension, that our freezers at home become a place for frozen food AND dead insects. This is clearly something that is shared with entomologists around the world (which means, of course, that there are thousands and thousands of freezers in homes that act has a short-term specimen storage location as well as a place for ice cream and frozen peas – that may either impress you, or creep you out).

A typical freezer: note the food AND the vials with dead insects.

A typical freezer: note the food AND the vials with dead insects.

Another generality that emerges from these Tweets is that our partners, friends and/or families often have to be our ‘helpers’: holding up a thumb for scale, being a good landing spot for mosquitoes, or holding various entomological equipment while we scramble on hands and knees to grab that elusive specimen.

LizzyLowe

Holidays? They sure are fun when living with an entomologist…

The division between “work” and “play” is a difficult one to make for entomologists: there is a single-minded joy associated with collecting our study species, no matter where you are (honeymoon?) and no matter the time of day. It’s actually quite fun to run around the backyard with a sweep net, chasing *that* butterfly. A few years ago I recall seeing a very lovely butterfly heading from my backyard to the front yard – I was barbequing (in bare-feet) at the time – thankfully the trusty sweep net was right next to the house. I made a dash for it, hooting and hollering the whole time. The butterfly was quick – so much so that it was about 200 ft up the street before I collected it. My neighbors then became very well aware of what I “do”: the barefoot entomologist.

The final personal anecdote I will share is the “Specimens on the doorstep” phenomenon, shared among many entomologists: once you are known as the “bug person” in your town or city, BEWARE – people will drop off mason jars with odd critters in them. You know, the beetle that is eating Samantha’s roses, or the ant found in a neighbor’s dishwasher. So often I come home and one of my kids says to me “Dad – there’s another jar for you on the kitchen table”. I guess this isn’t all that normal…?

Fire ants at the foot of the bed. Oh my.

Fire ants at the foot of the bed. Oh my.

The hashtag #LivingWithAnEntomologist certainly took off: It’s clear that this concept hit a nerve, and that my own observations were actually quite general. SO many people tweeted their stories about what it’s like to live with an entomologist. Thank you to a most wonderful community of friends and colleagues.

To my dear and loving family: I’m sorry (But not really).

Cheep cheep.

——

* Note: I have some minor hearing loss, and despite EVERYONE telling me about chirping crickets in our house, I just don’t hear them. Lucky me, I suppose.

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.

Reference:

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…

Studying natural history by stealth

Natural history can be defined as the search for, and description of, patterns in nature. I see natural history research as a more formal and structured approach to studying and recording the natural world. I also see this kind of research as a branch science that is often driven by pure curiosity. Many well-known and popular scientists are naturalists (ever hear of David Attenborough or E.O. Wilson?), and we can see that curiosity is one of the underpinnings of their work and personalities. Natural history research is, without doubt, very important, but in world of academic research, it sure doesn’t headline as pulling in multi-million dollar grants, nor does “natural history” appear in the titles of high profile research papers.

Is there a place for curiosity-driven natural-history research in today’s science? If so, how do we study it in the current climate of research?

Arctic wildflowers. Worthy of research... just because?

Arctic wildflowers. Worthy of research… just because?

This is big question, and one that we grapple with occasionally during my lab meetings. Most recently this came up because I challenged one of my students when they wrote about how important their research was because “…it hadn’t been done before“. In the margin of their work, I wrote “…so what? You need to explain how your work advances the discipline, and the explicit reasons how your research is important independent of whether or not it has been done before“.

Am I wrong? Is it acceptable to justify our research endeavours because they haven’t been done before?

The context matters, of course: some disciplines are very applied, and the funding model may be such that all or most research is directed, project-oriented. The research may have specific deliverables that have importance because of, perhaps, broader policies, stakeholder interests, or needs of industry. In other fields, this is less clear, and when working in the area of biodiversity science, such as I do, we constantly stumble across things that are new because they haven’t been studied before. And a lot of these ‘discoveries’ result from asking some rather basic questions about the natural history or distribution of a species. These are often things that were not part of the original research objectives for a project. Much of natural history research is about discovering things that have never been known before and this may be part of the reason why natural history research isn’t particularly high-profile.

Here are just a few examples of interesting natural history observations from our work in the Arctic:

This is the first time we observed the spider species Pachygnatha clerki on the Arctic islands!

Wow, we now know that an unknown parasitoid species frequently parasitizes the egg sacs of a northern wolf spider species!

Females of this little pseudoscorpion species produce far more offspring than what had been previously documented!

Now, if I wanted to follow-up on any of these observations, I think it’s fair to state that the research would be curiosity-driven, and not necessarily grounded in a theoretical or conceptual framework. It’s the kind of research that can be rather difficult to get funded. It’s also the kind of research that is fulfilling, and a heck of a lot fun.

I'm likin' these lichens. And surely data about them is required...

I’m likin’ these lichens. And surely data about them is required…

How then do you study such fascinating aspects of natural history? How do you get out to the field to just watch stuff; record observations just for the sake of it; spend time tabulating life history parameters of a species just because it’s interesting?

Perhaps you have the luxury of doing natural history research as your full-time job: You may be able to sit back and have people send you specimens from around the world, and maybe go out on an extended collecting trip yourself. You may be lucky enough (and wealthy enough?) to devote serious amounts of time to “think”, measure and record data about species. Perhaps you can even take a long walk each day to mull over your observations. Maybe you will gather enough observations to eventually pull together some generalities and theories, and perhaps you will get around to writing a book or manuscript about this….

Reality check: Most of us don’t have that luxury. Instead, we chase grants, supervise students, do projects that fit in with our unit’s research area, and publish-or-perish in the current model of academic research. Despite how we might long for the “good old days” of academia, they are gone (at least in my discipline). It’s rare that a University Professor or research scientist is hired to do stuff just to satisfy her or his own curiosity.

That main sound depressing to some, and hopeless, but it’s not meant to be. I do believe there are still ways to do exciting and interesting natural history research, and we can call it research by stealth.

In my field of study, establishing a research programs means getting grant money, and these are often aligned with priorities that matter to government, to policy, or to a particular environmental threat such as climate change or invasive species. It’s important to get these grants, and work with students and collaborators to try to solve some of the large and complex problems of the world. I am not advocating avoiding this. Instead, as we move along with these big projects, there are also countless opportunities to do a little natural history research, by stealth. Our first priority may not be the collection of natural history data, but nothing stops us from finding creative ways to make careful and meaningful natural history observations.

When taking a lunch break on the tundra, take a little longer to watch the Bombus flying by, or write down some observations about the bird fauna in your local study site, even if you aren’t an ornithologist. Keep a journal or sketch a few observations while you are sitting in the back of the field truck on that long drive up to the black spruce bogs. Each year, buy a field guide for a different taxon, and learn new stuff alongside your focused project. This ‘spirit’ of natural history observation is one that I promote to my own students, and I encourage them to follow up on some of these as a side-project to their main thesis research. Often, these end up being published, and end up in a thesis, and they certainly end up informing us more about our study species or study area.

Lunch break on the tundra: an opportunity for natural history observations

Lunch break on the tundra: an opportunity for natural history observations

Despite writing all of this, I still think my comment in my student’s writing will remain: we have to look at the importance of our research in the context of the bigger picture – it’s not enough to say something is important because it hasn’t been done before, and I’m not sure a PhD thesis can (or should) be entirely based on natural history observation. I would not be doing my job as a supervisor if I promoted curiosity-driven natural history research as the top priority for my student’s projects. To be candid: they won’t get jobs or publish papers in the higher profile journals (i.e., those ones that matter to search committees), and they won’t be well equipped when they leave my lab and head to another institution.

…But I will promote natural history research by stealth.

I think there is loads of room for curiosity-driven natural history research in today’s science. We may need to be creative in how we approach this, but, in the end, it will be worth it. We satisfy our curiosity, and learn a little more about the world along the way. We will also gain perspective and experience, and my students will be well equipped for a future in which natural history research is valued more highly then it is now.

Meet the lab: Elyssa Cameron

Here’s another in the “Meet the lab” series – written by Master’s student Elyssa Cameron.

Like many in my field, my love of nature and the creatures which inhabit it began much earlier than I can remember. From camping trips to day camps to museums and everything in between, I have always been passionate about understanding the world around me. Whether I was catching butterflies, trying to identify an elusive bird, exploring a new place or simply basking the in the beauty and wonder of an unaltered landscape, I knew that I wanted to be an advocate for nature.

Elyssa

Elyssa Cameron, with a furry friend.

In 2011, this led me to pursue an undergraduate degree at McGill University in Environmental Biology, specializing in wildlife. Here I learned the skills and thought processes that would help guide me on my journey. This is also where I feel in love with ecology and ecosystem dynamics. I was humbled by the enormous web of complexity which governs our world and sought to discover where exactly my interests lay. My search took me to South Africa, where I spent 3 week learning about wildlife management, game ranching, governance of national parks, and the challenges in maintaining healthy, safe, sustainable populations and ecosystems. It was during this trip that I realised that the management and conservation of any ecosystem needed to rest upon a solid understanding of the ecology of the system as well as the interactions of individual species, between different species and between species and their environment. Without this basic knowledge of how something works, one cannot hope to protect it.

giraffe

With this newfound drive for management and conservation through a better understanding of ecosystem ecology, I signed on to do a Master’s project with Chris Buddle (McGill University) on arctic arthropods in 2014. Having never truly worked on insects and spiders before, I knew such an undertaking would be a challenge; but one that I was excited to take on! The aim of this project is to establish a more comprehensive long-term ecological monitoring program in Cambridge Bay, Nunavut, by linking patterns of vegetation and habitat diversity to arthropod diversity. In this way, we can examine the arctic ecosystem in a more complete way and not as a series of individual pieces. This will allow for more effective management in this rapidly changing ecosystem and will hopefully provide more predictive power for models and policies.

However, to obtain these baseline conditions, we must first collect the data. This took me on my second great adventure – a summer in Canada’s high arctic! For those of you who have not yet experienced the vast and diverse beauty of Canada, it is something I cannot recommend enough. But be forewarned, there are LOTS of bugs – which was great for the Bug Team! Working in association with CHARS (Canadian High Arctic Research Station) the Bug Team was part of a unit of researchers set on better understanding the arctic ecosystem and promoting interdisciplinary collaboration. We sampled spiders, flies, beetles, wasps and others to try and get the most complete view of the species diversity and community structure as we could in such a short summer.

Arctic

Elyssa’s Arctic Adventures!

While there, we also did a number of community outreach programs to try and get the locals interested in science. We participated in a science night, made insect and butterfly collections to leave at the high school and Sarah Loboda (one of my wonderful lab mates!) organized day camp activities for the kids.

Now back at McGill, I spend most of my days in the lab looking through a microscope. With the general sorting of samples now complete, I am about to embark on my biggest challenge yet: species identifications! Both scary and exciting; but with the great support system here, I’m not worried.

As of January, I will also be co-supervising an intern from the Vanier Wildlife Technicians program with Chris Cloutier (the lab’s resident mosquito expert).

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.

Reference:

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

Meet the lab: Sarah Loboda

This is the second in a series of posts that will introduce the members of the arthropod ecology lab. This one is about Sarah Loboda:

I am not one of those people who can reflect back on my childhood with memories of chasing butterflies with a net. Instead, I could be found shouting loudly when seeing a spider in the bathtub. Things change… today I study community ecology of Arctic arthropods, and have a deep passion for arthropod of all kinds, from spiders to butterflies and flies.

Sarah, with a butterfly net.

Sarah, with a butterfly net.

My interest in entomology began as a challenge, and I love challenges! When I was an undergrad at Université du Québec à Rimouski, Québec, a tackled the big challenge of learning to identify insects. During my undergrad, I participated in several research projects where I could encounter biodiversity of insects and spiders and I developed a curiosity and a fascination about arthropods, particularly those living in extreme Arctic environments. Arthropods are ectotherms, yet they survive, year-round, in a region where the climate is very harsh. I quickly realized that the taxonomy was not the only interesting aspect in entomology. I wanted to identify arthropods in order to do research on community ecology. During the final year of undergrad in Rimouski, I decided to do a research project on the community ecology of spiders in salt marshes. As part of this project, I met Chris Buddle who encouraged my passion for entomology and the Arctic and I was lucky to do a Master’s project on spiders in the Canadian North as part of the Northern Biodiversity Program.

I take all opportunities to do outreach, and talk about insects and spiders with anyone who is interested. I am also involved in different societies, including the Entomological Society of Canada, and the Entomological Society of Québec, for which I’m the student representative. I love to volunteer and organize activities for members. Being the mother of two children, I also like to share my passion about arthropods with my kids, their friends and classmates in schools or daycares.

Sarah in front of her awesome poster at an Entomological Society of Canada meeting. This poster was a runner-up for a prize!

Sarah in front of her awesome poster at an Entomological Society of Canada meeting. This poster was a runner-up for a prize!

I have just started the second year of my Ph.D. I work with the veritable goldmine of data that has been collected from Zackenberg (northeast Greenland), where a long term monitoring program of arctic biodiversity has existed since 1996. My primary research objective is to assess temporal changes of the Arctic fly communities in this region, using the Muscidae and Phoridae families as model study taxa. The second objective of my research project will be to assess phenotypic and genetic changes over the last two decades in two species of Arctic muscids from Zackenberg. For this project, I am co-supervised by Jade Savage, a muscids expert from Bishop’s University, and Toke Høye from Aarhus University.