June 6, 2013 by Chris Buddle

How I traded field biology for a desk job

As I was looking at my summer schedule, it occurred to me that my time out in the field (here defined as outside, collecting data, probably wearing zip-off pants and carrying a field book, insect net and a set of vials) has been getting less and less, every year. As a PhD student I spent most of my summer collecting data. I loved it – the rugged joys of bumpy back-roads in Alberta, the sticky and smelly combination of sweat and bug spray, the cold beer at the end of a long field day. As I moved on to a post-doc in Ohio, I still spent a lot of time collecting spiders in soybean fields, helping other graduate students in the field, although the summers also included some lab work, and substantial time writing manuscripts.

When starting at McGill over 10 years ago, I kick-started my research program by spending weeks in the field, and seemed to manage a lot of time with each of my graduate students during the field season. However, time in the field was measured as weeks, and not months. Now, as I look at my schedule, I’m “maybe” going to get one full week in the field this summer, and a fews days here and there helping with other projects going on in the lab. My time doing field work, actively collecting data, is minimal.

Deep thoughts: field work in the Arctic. Are these days long gone…?

Wait a second. One reason I got into this business was because I like to figure out neat stuff about nature, while being in nature. As a child, I always enjoyed being ‘in the field‘ (this is also known as ‘playing outside‘) and wanted to continue this as an adult. What happened?

Academics in my discipline of study (let’s call it ‘field ecology‘) and at my career stage (i.e., some years into the job) spend relatively little time in the field and the bulk of their time is a desk job, click-click-clicking away on a keyboard. Staring at a monitor. I know there are exceptions (and BIG congratulations on those of you who do manage to get outside to collect data, regularly!), but when I look around to my colleagues, most of them spend more looking out a window instead of being out that window. The time gets chewed up by other (important) priorities: grant writing, editing manuscripts, writing manuscripts, answering emails, reading papers, attending meetings, chairing meetings, going to conferences, preparing talks for those conferences, writing lectures, delivering lectures and so on. These are all the current demands on our time, and they are the things that the job requires! (for other relevant discussions about this, have a peek at this post by Sarah Boon, and I’ve previously written about how I spend my time).

Bottom line: most of my work duties are indoor activities. I am fortunate in that some of my teaching occurs outside, but that is not the norm. The other thing that happens is ‘life’ – time with family is important to me, and time away from family is difficult. One reason I’ve spent less weeks away is because it’s tough on all of us and I like being around when the kids are growing up. There’s also that thing called a vacation – Academics typically their vacation time during the summer. (related to this is a post over at Dynamic Ecology titled “how often do you travel”, by Meg Duffy)

That is how I have traded field biology for a desk job.

I’m not alone: here are some responses from folks on Twitter when I asked about their experiences, and whether they have traded field biology for a desk job:

This is not a lament; this is not a sob story. In fact, perhaps many of us are OK with this transition from field biologist to ‘research manager’:

There is an important message here for people moving up through the Academic system: current PhD and MSc students need to recognize that the idea of landing an Academic job that gets you ‘out in the field’ a lot is probably a pipe dream.

I’ll end with some optimism: Even though things have changed, I think I can still call myself a ’field ecologist’ and here’s why:

1) “Field Trips” can be short. It’s possible to capture an hour outside over lunch and collect data on Agelenopsis spiders in a hedge near the picnic table, or stop off at a bird banding station in the AM before work, or swing by a forest to check a pitfall trap on the way home. I have come to realize that field work need not be ‘weeks away’. In many cases, it’s worth starting up a project that takes you outside regularly, at a local field site. This makes the field work an easier part of the day and you don’t need to schedule weeks away (nor will you need to schedule it months in advance). Keeping it simple, and keeping in manageable is important for me, given the other constraints on time.

2) Trade-offs: I spend time in the field instead of attending a lot of conferences. I have always enjoyed going to scientific conferences, but given the difficulties in getting away for extended periods of time, I realized that I could do field work, or attend conferences, but doing both is not always possible. One of my academic mentors discussed this with me soon after I had started my job at McGill (ironically, at a conference!); he said that when the weather is good, time was better spent collecting flies rather than sitting in a hotel basement. Good point. (By the way, summer-conference are kind of annoying because of this conflict!). Networking at conferences is very valuable, but that face-to-face networking may not be as essential later in a career. Thanks to social media, it’s also possible to attend conferences virtually.

3) Live vicariously through students: My thoughts about field work are somewhat nostalgic and dreamy, and I forget about the problems. I forget about the flat tires, encounters with bears, the biting flies, and the exhaustion. I’m reminded of these things when my graduate students come back from the field, and sometimes I am happy I wasn’t with them. I can, instead, spend a day or two with them in the field, troubleshoot, help but not have to suffer through it all. I’m a ‘gentleman field biologist’ now. Is that lame? Is that pathetic? Nope. I’ve put in my time and can now have my field trips field with all the fun parts and less of the annoying parts.

4) Mixing vacations with field biology: I’ve not been all that successful at this, but I do know colleagues who manage to mix extended vacation time with field work. I do this on a smaller scale, and it typically includes carrying vials along with every trip, whether it is to the family cottage, or just a walk in the local forest. I’m always after records of pseudoscorpions, and have managed some nice finds while on vacation. My family does, however, gives me strange looks when I go chasing after spiders or butterflies during lunch break while on a road trip. I can handle the ridicule –> it’s for science!

Although I have largely traded field work for a desk job, there are still glimmers of exciting field work, and still opportunities to get outside and be reminded of the reasons why I originally got into this line of work. I am not depressed or sad about my desk job – I have the best job in the world, despite the the fact that I stare out the window and sometimes dream of field work. I also maintain that these things come in cycles – a few years ago I was away for a few weeks in the field, even if this year is less intensive. It’ll come around again, and perhaps I will write a post in the future that discusses how it’s possible to be a gritty, smelly, rough and tough field biologist again. For now, though, I must stop typing. It’s hard work and my fingers are a little sore.

May 9, 2013 by Chris Buddle

The case of the missing genitalia: copulation costs for male spiders

This post is written by Chris Buddle (Associate Professor, McGill University). This article was originally published in “The Canadian Arachnologist” – a newsletter about Arachnology in Canada (this newsletter is no longer being published).

Spider sex can be a dangerous and costly venture, the classic example being the (often) misunderstood act of sexual cannibalism (e.g., the black widow spider). However, many of the costs for males are not always so obvious: during copulation, the emboli of some male spiders may break off, which results in the male being unable to properly re-fill his palpal organ and mate again (Foelix 1996). Without this ability, the male’s future is essentially an early retirement. While sorting and identifying spiders for my dissertation research, I noticed that male Cybaeopsis euopla (a ‘hackledmesh’ weaver spider) seemed to frequently be missing one or both of their pedipalps. Could this be another example of a copulation cost?

Looking to the literature, missing pedipalps are documented with some species – tiny males from the sexually dimorphic genus Tidarren (Theridiidae) will remove their own palps and this increases their running speed considerably (Ramos et al. 2004). Working with the same genus, Knofach and van Harten (2001) observed that females remove one of the male’s palps ‘after achieving genitalia coupling’. The female then proceeds to eat the male, while the detached palp acts as both a mating plug and continues to inseminate the female! Something similar happens with the species Nephilengys malabarensis and this fascinating biology was reported by science bloggers such as Ed Yong. In the wolf spider (Lycosidae) Pardosa milvina, frequent palpal losses were observed and effects on courtship and mating were studied by Lynam et al. (2006). Perhaps not surprisingly, these authors report that ‘intact males were less likely to be cannibalized and suffered fewer predatory attacks by females than autotomized males’.

With that background, I began counting the frequency of missing pedipalps for a sub-sample of the specimens of C. euopla. The objective was to assess the percentage of males were missing right, left, or both pedipalps and see if this related to phenology or other life-history events.

The samples came from a mixed-wood forest at the George Lake Field Station, located about 75 km NW of Edmonton, Alberta. This mature mixed-wood forest is dominated by trembling aspen and balsam poplar. Samples were collected using standard pitfall traps, and were part of several other projects on spider assemblages in mixed-wood boreal forests (e.g., see Buddle 2001).

Cybaeopsis euopla – lovely little spiders! (Photo by C. Buddle)

Cybaeopis euopla (Amaurobiidae) (formerly Callioplus euoplus) is widespread in Canada, ranging from the Maritimes to the far north-west (Leech 1972). Males are about 3.5 to 5 mm in length, and are pale orange to light brown in colour. Specimens are typically collected from the leaf-litter of closed-canopy deciduous forests (Leech 1972; Buddle et al. 2000). From a sample of 653 male C. euopla, I found a total of 309 (or 47%) to be missing either one or both pedipalps. This is an impressive number, and essentially means that about half the males in the population are missing the very parts of their bodies that are required for reproduction. Of the 309 that were missing pedipalps, 124 were missing the left pedipalp, 97 were missing the right pedipalp, and 88 were missing both. In virtually all cases, the pedipalp was severed at the trochanter-femur joint. So the most plausible explanations for missing pedipalps are:

Pedipalp autotomy occurs during the act of copulation
The female may remove the pedipalps before, during or after copulation
C. euopla males may use their pedipalps in antagonistic courtship behaviours
Perhaps pedipalps are frequently used to grapple with aggressive prey, and are thus damaged.

It would be difficult to relate missing pedipalps to the act of copulation without detailed studies of courtship and copulation in C. euopla. However, the fate of pedipalps could be determined indirectly if the frequency of missing pedipalps increased during the reproductive period. The period of reproduction for ground-dwelling spiders, such as C. euopla, can be assessed from the peak activity period for male and female spiders, inferred from a passive sampling technique such as pitfall trapping. Using a larger data-set for male and female C. euopla collected by pitfall traps set at the George Lake Field Station, it is evident that males are most active early in the season (early May through the end of June) (Figure 1). Females were found throughout the spring and summer months over two years, with a slight increase in late June (Figure 1). These results generally agree with Leech (1972), who suggests May and June are the main periods of activity for C. euopla. Thus, it is inferred that this species will mate primarily in the spring in central Alberta.

The next step is to ask whether the frequency of missing pedipalps is related to the hypothesized mating period. This was done by calculating the average percentage of males with missing pedipalps as a function of sampling date (Figure 2). In both sampling years, the percentage of males with missing pedipalps increased as the season progressed (Figure 2). Although the sample size for July samples was low (12 individuals), the average number missing pedipalps was over 80%. Furthermore, the earliest sampling date in 1999 (6 May), which collected over 200 individuals, had the lowest average percentage of males with missing pedipalps (< 20%). These results indirectly suggest that as the season progresses, and the spiders mate, males begin to lose their pedipalps. I can therefore likely exclude the possibility that palpal loss is related to aggressive prey, and the explanation is likely related to courtship or copulation.

This small study has raised as many questions as it has answered, and there are certainly other explanations that I have failed to mention. I invite fellow Arachnologists to comment on the phenomenon of missing pedipalps in C. euopla, and in other species. I suspect pedipalp loss is widespread, but seriously understudied. Given this importance of palps to the fitness of spiders, future research is certainly warranted.

References:

Buddle, C. (2001). Spiders (Araneae) associated with downed woody material in a deciduous forest in central Alberta, Canada Agricultural and Forest Entomology, 3 (4), 241-251 DOI: 10.1046/j.1461-9555.2001.00103.x

Buddle, C., Spence, J., & Langor, D. (2000). Succession of boreal forest spider assemblages following wildfire and harvesting Ecography, 23 (4), 424-436 DOI: 10.1034/j.1600-0587.2000.230405.x

Foelix, R.M. 1996. The Biology of Spiders. Oxford University Press.

Knoflach, B., & van Harten, A. (2001). Tidarren argo sp. nov. (Araneae: Theridiidae) and its exceptional copulatory behaviour: emasculation, male palpal organ as a mating plug and sexual cannibalism Journal of Zoology, 254 (4), 449-459 DOI: 10.1017/S0952836901000954

Leech, R. 1972. A revision of the nearctic Amaurobiidae (Arachnida: Araneida). Memoirs of the Entomological Society of Canada 84: 1-182.

Lynam, E., Owens, J., & Persons, M. (2006). The Influence of Pedipalp Autotomy on the Courtship and Mating Behavior of Pardosa milvina (Araneae: Lycosidae) Journal of Insect Behavior, 19 (1), 63-75 DOI: 10.1007/s10905-005-9008-x

Ramos, M. (2004). Overcoming an evolutionary conflict: Removal of a reproductive organ greatly increases locomotor performance Proceedings of the National Academy of Sciences, 101 (14), 4883-4887 DOI: 10.1073/pnas.0400324101

April 9, 2013 by Chris Buddle

Spiders as catalysts for ecosystem development

It is well known that spiders are effective at dispersal and colonization, in part because of their ability to ‘balloon‘ – small spiders (i.e., immature specimens, or adults of species that are small) will release a strand of silk and let the wind pick them up and carry them far distances. This passive ability to disperse has served spiders well, and enabled them to be among the first animals to colonize new habitats. For example, after the eruption of Mount St Helens, the depopulated Pumice Plain was re-colonized over time, and biologists kept an eye on what was dropping from the skies. Not surprising (to me!) was that spiders represented a lot of this ‘aerial plankton‘ – Crawford et al. (1995) reported that spiders represented “23% of windblown arthropod fallout and contributed 105 individuals per square meter“.

A spider about to launch! Photo by Bryan Reynolds, reproduced here with permission.

Many, many people have recognized this amazing ability of spiders to get to places effectively and quickly. During his voyages on the HMS Beagle, Darwin observed and commented on this. He noticed spiders landing on the ship when they were far offshore. Here’s a lovely quote:

These, glittering in the sunshine, might be compared to diverging rays of light; they were not, however, straight, but in undulations like films of silk blown by the wind.

-Charles Darwin, Voyage of the Beagle, 1832

A wonderful paper titled “Distribution of Insects, Spiders, and Mites in the Air” (Glick 1939) also discusses aerial plankton. In this work, Glick reports on how a plane was used to collect arthropods in the skies – this was done by modifying the plane so it had a collection net attached to it. Spiders were among the most commonly collected taxa, and were found up to 15,000 ft in altitude. Glick followed this up with work published in 1957, and spiders were again reported as common aerial plankton.

Convinced? Spiders really are everywhere and can get anywhere – from dominating the tundra, to floating far above as tiny eight-legged aeronauts.

This takes me (finally) to the point of this post, and some reflection about a paper by Hodkinson et al. (2001), titled “What a wonderful web they weave: spiders, nutrient capture and early ecosystem development in the high Arctic – some counter-intuitive ideas on community assembly”. In this work, the authors provide some data about aerial plankton in a series of sites representing different stages of succession in Midtre Lovénbreen – a ‘small valley’ glacier in Spitsbergen (a Norwegian high Arctic Island). This forum paper was meant to present an idea about ecosystem development in the Arctic, with a focus on spiders and other aerial plankton and their relationship to nutrients.

Spiders are among the first to arrive due to their amazing abilities at dispersal and colonization.

Many spiders will just die, and their sad, little bodies will decompose and leave behind nutrients.

Many of the spider species that arrive will build webs, and the silk contains many nutrients. Regardless of whether the silk successfully captures prey, the silk will eventually be a hot-spot of nutrients.

A lot of other aerial plankton will hit these webs – this will include other arthropods (Hodkinson et al. rightfully point out the importance of Chironomids, or midges, as key prey for spiders in the north) and these prey may or may not be eaten by spiders. The aerial plankton also includes other ‘debris’ that would be floating around (fungal spores, dirt, etc). The webs capture all these goodies, and act as a concentrated area for a growing soup of nutrients.

The spider webs will collect moisture. In Arctic systems, dry polar-deserts, and many other newly created habitats, the accumulation of moisture is rather essential for continued ecosystem development.

Taken together, Hodkinson et al. (2001) argue that spiders and their webs represent little pockets of concentrated nutrients in landscapes that are void of much other life. These hotspots could be catalysts for ecosystem development in systems that are starting from scratch. I really like this idea – not only does is stir up the imagination (little spiders gently falling from the sky, landing on habitat never before touched by animals, and providing the start of an ecosystem…), it really makes some biological sense. Ecosystem development requires nutrients and substrates – of course, these would both be available without spiders, but our eight-legged friends are helping move things a long a little more quickly.

The paper by Hodkinson et al. has been cited less than I would have expected. Although they don’t provide any experimental data, their ideas are interesting and relevant and should be studied in detail. Recently, a few papers have come out that are taking the ideas to the next level. Konig et al. (2011) studied arthropods of glacier foregrounds in the Alps. They found that although Collembola and other ‘decomposers’ are quite important in early successional stages, overall, generalist predators (including spiders) were dominant and using stable isotope analyses, they showed that these generalist predators often ate each other – an interaction known as intraguild predation.

I often discuss Hodkinson et al.’s (2001) paper in lectures, and invariably I get the question “If spiders are first to arrive, what do they eat?“. I typically answer that spiders eat other spiders, and it’s reassuring to see literature that supports this claim. In turn, intraguild predation itself contributes further to the accumulation of nutrients (more sad, little spider bodies littering the landscape…).

Placing this work in a more general framework, these ideas are pointing to the increased importance of predators in overall nutrient dynamics in ecosystems. I was thrilled to see a paper by Schmitz et al. (2010) that argues “predators can create heterogeneous or homogeneous nutrient distributions across natural landscapes“. Bingo. This is exactly what Hodkinson et al. were arguing – predators, such as spiders, can arrive quickly to an area, and in the context of newly formed ecosystems, may provide a hotspot for nutrients in an otherwise desolate landscape.

Although the Hodkinson et al. paper is over a decade old, it’s still relevant, and quite important. I suspect that if more newly created habitats are studied in detail, spiders will indeed prove to be catalysts for ecosystem development.

References:

Crawford, R., Sugg, P., & Edwards, J. (1995). Spider Arrival and Primary Establishment on Terrain Depopulated by Volcanic Eruption at Mount St. Helens, Washington American Midland Naturalist, 133 (1) DOI: 10.2307/2426348

Hodkinson, I., Coulson, S., Harrison, J., & Webb, N. (2001). What a wonderful web they weave: spiders, nutrient capture and early ecosystem development in the high Arctic – some counter-intuitive ideas on community assembly Oikos, 95 (2), 349-352 DOI: 10.1034/j.1600-0706.2001.950217.x

König, T., Kaufmann, R., & Scheu, S. (2011). The formation of terrestrial food webs in glacier foreland: Evidence for the pivotal role of decomposer prey and intraguild predation Pedobiologia, 54 (2), 147-152 DOI: 10.1016/j.pedobi.2010.12.004

Schmitz, O., Hawlena, D., & Trussell, G. (2010). Predator control of ecosystem nutrient dynamics Ecology Letters, 13 (10), 1199-1209 DOI: 10.1111/j.1461-0248.2010.01511.x

A special thanks to Bryan Reynolds for permission to use his photograph of the dispersing Pisaurid spider. Please visit his work here.

March 26, 2013 by Chris Buddle

Seasonality of Arctic Beetles

I’m excited to report on paper written by Crystal Ernst, PhD student in my lab, and well known as the “Bug Geek“. This paper is a product of the Northern Biodiversity Program (yes, it sure is great that the papers from this project are starting to appear!), and will be one of Crystal’s PhD thesis chapters. The paper is titled Seasonal patterns in the structure of epigeic beetle (Coleoptera) assemblages in two subarctic habitats in Nunavut, Canada

A very nice Arctic beetle! (photo by C. Ernst, reproduced here with permission)

Here’s a plain-language summary of the work:

Although we often think of Arctic systems as cold and lifeless, Canada’s tundra habitats are home to a high diversity of arthropods (insects, spiders and their relatives). Beetles are important insects on the tundra – filling ecological roles as predators (feeding on other insects), herbivores (feeding on plants), mycophages (feeding on fungi), and necrophages (feeding on dead or decaying animals). In this research, we wanted to find out what happens to ground-dwelling Arctic beetles as a function of seasonality. We were curious about whether different species occurred at different times during the short Arctic summer, and whether the functions of the beetles changes over the summer. This is an important area of study because beetles perform important ecological functions, and knowing how these functions change over time may have broader implications for northern ecosystems. This is especially relevant in the Arctic since these systems have a short ‘active season’, and climate change is disproportionally affecting northern latitudes. If climate change alters an already short summer, what might happen to the beetles?

This research was done as part of the Northern Biodiversity Program (NBP) – a broad, integrative project about the diversity of insects and spiders across northern Canada. The NBP involved collecting samples at 12 sites in the Arctic, but at one of these sites (Kugluktuk, in Nunavut) we had an opportunity to do a more detailed collection over the entire summer of 2010. This involved setting out traps for the entire active season, from June through to August. These traps were plastic containers sunk into the ground – beetles that wander along the tundra fall unawares into these traps, which contain preservatives, and are trapped until a researcher collects the samples. Traps were placed in wet and (relatively) dry habitats so that we could compare the two habitats. After the collections were returned to our laboratory, the beetles were identified to species, counted, and the biomass of the beetles was estimated – biomass lets us determine what happens to the ‘amount of beetles’ on the tundra in addition to figuring out ‘how many’ (abundance) and ‘what kind’ (species) were in the traps. The beetles were also classified into their key ecological roles. The data were then compared as a function of when traps were serviced to let us assess what happens to beetles as a function of seasonality.

We collected over 2500 beetles, representing 50 different species – remarkably, 17 of these species represented new Territorial records. This means that 17 of the species that were identified had never before been recorded in all of Nunavut! Although many ecological functions were represented by the beetles we collected, most were predators. We documented that wet habitats had different kinds of beetle species than the drier tundra habitats, even though the actual number of species between the habitats did not differ. We also uncovered a seasonal affect on the functions of beetles in the system – as the season progressed, the beetles tended to be represented more by predators compared to earlier in the season, which was dominated by beetles representing a diversity of functions. The mean daily temperature also related to the seasonal change that was observed in the beetles.

PhD student Crystal Ernst, happily working on the Arctic tundra.

This work is one of the first to carefully quantify how beetles change during short Arctic summers. We found a diverse assemblage of beetles, filling a range of ecological roles. These ecological roles, however, do not stay the same all summer long, and the shifts in the beetles were related to mean daily temperature. Given that Arctic systems will be significantly affected by climate change, this is worrisome – if temperatures increase, or become more variable, this may affect ecosystem functions that are mediated by beetles. This is more evidence supporting the need to track climate change in the Arctic, and play close attention to the small animals of the tundra.

Reference:

Ernst, C., & Buddle, C. (2013). Seasonal patterns in the structure of epigeic beetle (Coleoptera) assemblages in two subarctic habitats in Nunavut, Canada The Canadian Entomologist, 145 (02), 171-183 DOI: 10.4039/tce.2012.111

February 20, 2013 by Chris Buddle

The greatness of pseudoscorpions

As you know, I’m quite passionate about Arachnology, from spiders, to harvestmen and Pseudoscorpions. These are all some of the creatures that fall into the category of the ‘obscure and amazing‘. On the topic of pseudoscorpions, a few very fun and interesting things have happened recently, and enough to warrant a short blog post. I also promised that I would post a few more videos related to some research activities on the hunt for pseudoscorpions in the Yukon.

1. Just look at this SEM of a pseudoscorpion!

A little while ago, my Arachnid friends and colleagues from Alberta, Heather Proctor and Dave Walter, forwarded me a stunning image of a pseudoscorpion taken with a scanning electron microscope (SEM). Dave was kind enough to give me permission to share it here:

SEM of a pseudoscorpion (Chernetidae) – copyright D. Walter (reproduced here with permission)

There really is something lovely about getting up close and personal with these little Arachnids. I don’t know this species, but it’s definitely in the family Chernetidae – a relatively diverse family, quite common across Canada. My favourite Yukon species, Wyochernes asiaticus, is also a Chernetid. Dave Walter really does some magic with his SEM images, and you are encouraged to check out is macromite blog (his home bug garden blog is also worth a peek!).

2. Just look at these videos about collecting pseudoscropions in the wild!

Speaking of my favourite Yukon species, I took a lot of videos of field work in the Yukon last summer and I wanted to share a few with you, here. Although our larger purpose for the trip was to complete some follow-up field work for the Northern Biodiversity Program, I also wanted to collect additional specimens of a wonderful pseudoscorpion species. The first video provides some context to the work, and gives you a bit of a flavour of the landscape up near the Yukon – Northwest Territory border in Canada:

Typically, pseudoscorpions are not that commonly encountered. In my experience, when they are encountered, you tend to see one or two. What is truly amazing is the sheer abundance of this species found under rocks in creek/river beds in the Yukon. Furthermore, you can see and collect multiple life stages, including females with eggs. This short video gives a taste for this abundance.

The third and final video is a big goofy, and highlight the ‘collecting gear’ and appropriate field attire for becoming a “pseudoscorpion hunter“. I am continually on a crusade to help generate enthusiasm for Arachnids, whether it is dispelling myths, or trying to inspire others to become Arachnologists (you know, we do need Arachnologists in Canada!).

One important caveat: you may NOT simply run to the Yukon and flip rocks to collect pseudoscorpions – many parts of the world, including the Yukon, have strict guidelines about what you can collect. Permits are required, and be sure to check into this before you plan on becoming an Arachnologist!

3. Just look at this pseudoscorpion necklace!

To further illustrate my rather quirky obsession, I managed to find a wonderful person on Etsy who was able to make me a pendant with a pseudoscorpion design:

The pseudoscorpion necklace. You want one.

Not only that, this design is actually from a photography I took a few years ago, and is an accurate depiction of the cosmopoliton species Chelifer cancroides.

Chelifer cancroides – my photo which was used to design the pendant

I KNOW you want to get yourself one of these… start a conversation with Lynn. Get yourself one of these necklaces and stand proud with other pseudoscorpionologists!

In sum, I do hope you find this post interesting, hopefully fun, and has whetted your appetite from more information about curious critters.

Stay tuned… I will continue to post more about Arachnids…

January 29, 2013 by Chris Buddle

Assessing five decades of change in a high Arctic parasitoid community

As my colleague Terry Wheeler mentioned on his blog, our Northern Biodiversity Program team is thrilled to see post-doc Laura Timms‘s paper about Arctic parasitoid wasps published in Ecography! Our team worked on Ellesmere Island, Nunavut, in 2010, and compared parasitoid wasps to historical collections from the same site that were made in 1961-65, 1980-82, and 1989-92. Parasitoid wasps are at the top of the insect food chain: they lay eggs inside or on top of other arthropods and the wasp larvae emerge after consuming their hosts – a gruesome but very common lifestyle for many types of wasps. Species at higher trophic levels, such as these parasitoid wasps, are often the first to respond to new environmental pressures, including the climate change that is occurring rapidly in Arctic systems.

Laura identified a LOT of wasps, recorded the type of host attacked (e.g. plant-feeding hosts versus hosts that are predators), and the body size of two species of wasps that were commonly collected in all time periods. We found no clear pattern of change in most aspects of the parasitoid wasp community on Ellesmere Island over past 50 years, even though temperature and precipitation have increased significantly during the same period. However, there were some signs that parasitoids of plant-feeding insects may be more affected more than other groups: one common parasitoid species that was abundant in 1960s hasn’t been collected since then, and the community in the 2010 study contained fewer parasitoids of plant-feeding insects than previous studies.

Some members of the Northern Biodiversity Program working in the Yukon in 2012. (l-r, Chris Buddle, Laura Timms, Crystal Ernst and Katie Sim)

Laura takes it as a good sign that no major changes in the ecology of the high Arctic parasitoid community have been observed, but isn’t taking it for granted that the community will remain unaffected for long. At 82°N, Ellesmere Island is relatively isolated, but other research has found that parasitoid communities further south are changing dramatically (Fernandez-Triana et al 2011).

Laura has the following comment about our work: “We hope that our findings will be used as baseline data for ongoing monitoring on Ellesmere Island”, said Timms. “We know so little about these high Arctic insect communities, we should learn as much as possible about them while they are still intact.”

References

Timms, L., Bennett, A., Buddle, C., & Wheeler, T. (2013). Assessing five decades of change in a high Arctic parasitoid community Ecography DOI: 10.1111/j.1600-0587.2012.00278.x

Fernandez-Triana, J., Smith, M., Boudreault, C., Goulet, H., Hebert, P., Smith, A., & Roughley, R. (2011). A Poorly Known High-Latitude Parasitoid Wasp Community: Unexpected Diversity and Dramatic Changes through Time PLoS ONE, 6 (8) DOI: 10.1371/journal.pone.0023719

January 24, 2013 by Chris Buddle

Where did all the spiderlings go? A story about egg-sac parasitism in Arctic wolf spiders

This week we are in a deep freeze in the Montreal area, so it seems somewhat fitting to discuss Arctic spiders. I’ve discussed the life-history of Arctic wolf spiders (Lycosidae) before, specifically in the context of high densities of wolf spiders on the tundra. Much of this work was done with my former PhD student Joseph Bowden. The latest paper from his work was published last autumn, and was titled ‘Egg sac parasitism of Arctic wolf spiders (Araneae: Lycosidae) from northwestern North America‘. In this work we document the rates of egg sac parasitism by Ichneumonidae wasps in the genus Gelis. These wasps are fascinating, and we have found them to be very common on the tundra. There are often multiple wasps in a single egg sac, and as is typical with Gelis, they leave nothing behind: all eggs within an egg sac are consumed. After fully developed, the adult wasps pop out of the egg sac; the Gelis adults we encountered had both winged forms and wingless females, the latter superficially resembling ants.

A Gelis emerging from a wolf spider egg sac. Photo by Crystal Ernst, reproduced here with permission.

The rates of parasitism of Pardosa egg sacs (by Gelis) were, at some sites, extremely high. In some cases over 50% of the wolf spider egg sacs were parasitized. Stated another way, half of all the females encountered with egg sacs had zero fecundity because the female was carrying around wasps within the egg sac instead of spider eggs.

It’s quite interesting to think about these wingless Gelis females: after emerging from egg sacs, they end up wandering around the tundra in search of hosts. Spiders with egg sacs must be encountered frequently enough for the wasps to grab on to a passing wolf spider in order to parasitize the egg sac. Recall, densities of wolf spiders can be very high in the Arctic (4,000 per hectare, at least). Hmmm…. this is all starting to fit… high densities of wolf spiders support high rates of egg parasitism and these wasps can ‘afford’ to be wingless since their hosts are frequently encountered: an interesting feedback loop! We can also speculate about large-scale gradients in diversity – many Ichneudmonidae show high diversity in northern regions. Within Gelis, it’s a good bet that they will find many suitable spider hosts in these environments.

Looking down the microscope – all those Gelis!

So, how extreme are these rates of egg parasitism? Looking at some of the literature, there are certainly a number of papers about wasps that parasitize spider egg sacs. Cobb & Cobb (2004) studied two Pardosa species in Idaho, and recorded a egg parasitism rate of about 15% (by Gelis wasps and wasps in the genus Baeus [Sceleonidae]). Van Baarlen et al (1994) studied egg parasitism in European Linyphiidae spiders and their maximum rates of parasitism were about 30%. Finch (2005) did a detailed study of four spiders species (non-Lycosidae) and rates of egg parasitism varied between 5% up to as high as 60% in an Agroeca species.

Our documented parasitism rates for Arctic wolf spiders are certainly quite high (for Lycosidae), but not out of the range of other published studies for non-Lycosidae. I do wonder whether we will continue to find high egg parasitism rates if more species were examined in detail – certainly a fertile area of study. Related to this, what are the population-level consequences of this interaction? What is the relationship between spider densities and parasitism rates? Although Joe and I did try to speculate on this, our data are preliminary – again, a key area for future research.

In the Arctic context, we will continue to uncover fascinating food-web dynamics. Our research group has already been thinking seriously about this – Crystal Ernst has written a nice post about the idea of an ‘inverse trophic web’ (i.e., predator-dominated) in the Arctic, and a fair amount of my future research will pursue this avenue of research.

Pique your interest…? Why not think about graduate school in my lab, and study Arctic arthropod biodiversity?

References:

Bowden, J., & Buddle, C. (2012). Egg sac parasitism of Arctic wolf spiders (Araneae: Lycosidae) from northwestern North America Journal of Arachnology, 40 (3), 348-350 DOI: 10.1636/P11-50.1

Cobb, LM & Cobb VA (2004). Occurrence of parasitoid wasps, Baeus sp and Gelis sp., in the egg sacs of the wolf spiders Pardosa moesta and Pardosa sternalis (Araneae: Lycosidae) in southeastern Idaho. Canadian Field Naturalist 118(1); 122-123.

Baarlen, P., Sunderland, K., & Topping, C. (1994). Eggsac parasitism of money spiders (Araneae, Linyphiidae) in cereals, with a simple method for estimating percentage parasitism of spp. eggsacs by Hymenoptera Journal of Applied Entomology, 118 (1-5), 217-223 DOI: 10.1111/j.1439-0418.1994.tb00797.x

Finch, O. (2005). The parasitoid complex and parasitoid-induced mortality of spiders (Araneae) in a Central European woodland Journal of Natural History, 39 (25), 2339-2354 DOI: 10.1080/00222930500101720

January 15, 2013 by Chris Buddle

We need the Taxonomy Hulk

The Taxonomy Hulk burst onto twitter yesterday. We need superheroes like Taxonomy Hulk. As his/her alter ego, s/he surfs the internet, working away as a taxonomist, doing things that taxonomists do – describing species, inferring their evolutionary relationships, discovering their natural history. However, if s/he spots a taxonomic mistake on a website, news story, scientific article, or blog – LOOK OUT. The Hulk goes through an impressive metamophosis. S/he gets mad and gets even. If you make a taxonomic mistake, you will be shamed. Message: DON’T MAKE A #TAXONOMYFAIL. Taxonomy Hulk points out misidentifications in images (e.g., see this website with a Harvestmen instead of a spider.. oops [although a common mistake]).

Taxonomy Hulk reminds us to use Latin names, not common names.

Taxonomy Hulk is also funny. We need humour – every day.

On a slightly more serious note: correct taxonomy is critically important. Other posts (e.g., see here or here) have pointed out taxonomic failures – and I especially like Bug Girl’s Flickr set!. One letter difference in Miridae (a family of plant bugs) gets you to Muridae (rodents and their relatives) – yeah those two are just a bit different. As an ecologist (although one with envy of taxonomists, and one in awe of the work taxonomists do!), I admit that I am perhaps not as careful as I should be when it comes to checking nomenclature, or ensuring spelling is always correct. I try – but given that my training is not in taxonomy, I surely make mistakes. I fear that some ecologists appreciate the importance of sound taxonomy even less than I do, and we need a watchdog. Reminders about correct taxonomy are a good idea. Taxonomy Hulk reminds us that we must be clear in what we are saying, whether it be in science journalism, writing a blog post, or working on a scientific paper.

Taxonomy Hulk is a concept not a person and this is a good thing: the humour and fun and ‘alter ego’ perspective is non-threatening, and allows taxonomic issues to be brought into the open easily and effectively. We can fix our mistakes, smile about it, and move forward.

Thank you Taxonomy Hulk. (and yes, you should follow Taxonomy Hulk on twitter)

I finish by stating that Taxonomy Hulk’s ‘regular’ persona (the Bruce Banner) is known to some of us (and s/he’s an incredibly competent taxonomist!, and a super-nice person).

But I’ll keep it quiet – it’s better that way.

January 10, 2013 by Chris Buddle

Natural History: unknown.

I sometimes see this statement in taxonomic papers that describe a new species:

Natural History: Unknown

Think about this… specimens have been collected, somewhere, sometime. Perhaps these specimens sat in an Entomology museum for decades until a MSc student took them out and started a revision. Perhaps the specimen was recently sorted from a bulk malaise trap sample from the Amazon basin, and sent to a taxonomic expert for identification. S/he recognized it was something different and later, while doing a taxonomic revision, included it, measured it, did a line drawing, extracted some DNA, wrote a description, gave it a name. However, when writing what is known about its natural history and biology had to write “unknown“. (by the way, discussions about defining natural history can be found here and here).

An unknown weevil with unknown natural history.

I recognize why nothing is known, but when trying to get some sense of why a particular species might be found in a particular habitat, having no information about natural history and biology can be frustrating. This is especially true for ecologists, whose research might benefit immensely from ANY natural history information. In my own work, after I key out a species of wolf spider, for example, I immediately flip to the description, and scan down to the notes about the biology of the species – these notes can confirm details about the species (hey look, I found it under rocks on a shoreline, and that is where it is reported, also!; or, indeed, it makes sense that I found that egg sac in late summer – that species is known to mate in mid-summer).

Natural history is important, as is so elegantly stated in many papers (e.g., see Greene’s 2005 paper) and the impending extinction of natural history was written about over 10 years ago by Wilcove & Eisner. The world needs natural history information, and although I recognize that having a name is clearly very important, it is also essential to have some natural history information. Such information can lead to additional research on the species, or allow others to document the species in new locations around the globe. Having some information will help future graduate students figure out when during the growing season they should find specimens, and perhaps what host plants they should look on.

So, I ask these questions, and I look forward to responses, especially from taxonomists:

Should taxonomists wait to describe a species until there are some details known about its natural history? (this will, of course, take more specimens and more time…)

and,

Under what conditions is it acceptable to state “Natural History: unknown”?

Caveats: I am coming from this question as an ecologist with an appreciation for taxonomy, but not as someone trained in taxonomy. I am, therefore, biased in my views. I also recognize that in many cases, taxonomists only have one specimen and a label to work with, and data on the label itself may be lacking, hence the need to state “natural history: unknown”. My questions are meant to be more general, and I am hoping to gain insights into whether seeking additional natural history information about species (when it is described) is a losing battle… and whether this task should be in the hands of the individuals who describe species.

References

Greene, H.W. (2005). Organisms in nature as a central focus for biology Trends in Ecology and Evolution, 20 (1), 23-27 DOI: 10.1016/j.tree.2004.11.005

Wilcove, D. and Eisner, T. (2000) The impending extinction of natural history. Chron. Higher Ed. Sept. 15, B24. Available here.

January 3, 2013 by Chris Buddle

Resolutions: from blogs to birds

Happy New Year!

End-of-year posts tend to be focused on reflections on the past year - now it is time to look forward and make some resolutions. From a personal perspective, I’m not a big fan of New Year’s resolutions. I’ll try to floss my teeth, exercise, and eat my veggies. However, I will forget about these or feel guilty and annoyed by the time February hits. I wonder if perhaps I can stick to my professional resolutions? Will it help if I wrote a post about these and make them very public? Why not give it a try

… here are six resolutions:

1. Keep blogging. I think this will be an easy one to keep – I achieved 75 posts last year and I’ll work to equal or better that. I’m motivated to write more posts: it’s fun, and provides immense value. I thought that perhaps blogging would get tiresome and I would run out of ideas. This is not the case. I have a lot of ideas, and will soon write about spider parasitoids (including this one), share some videos related to field work from last summer, discuss the pros and cons of comprehensive exams in PhD programs, and discuss uses of technology in teaching (or not…back to chalk?). I’ll also work to follow good advice for writing science posts.

2. Finish the Opiliones Project. For new followers, this was a project that uses twitter to share the information from a fabulous (but expensive) textbook about Harvestmen – fascinating cousins of spiders. The project is about 3/4 of the way finished. I will do my best to find a bit of time to wrap this up, archive it, and write a summary post… before winter’s end!

An Opiliones from Panama (with mites, too!)

3. Back to the Microscope. It’s seldom I can find the time to use that magical tool – you know, that thing that you look into and it makes stuff big? I really am going to try to rediscover my love of Arachnid taxonomy. I’m thinking of starting with jumping spiders, and would like to work on a larger project about the local jumping spider fauna.

4. Manuscripts! Quite a few of my graduate students will be finishing up this year – the Northern Biodiversity Program is coming to a close, and I hope to get manuscripts submitted for publication. The work is very exciting, and that project has really been a catalyst of change – and the bulk of my research next year will have an Arctic focus. However, I don’t feel a project is fully completed until all the manuscripts are submitted.

5. Get control of email. I must be honest: this is the resolution that will be really tough to keep. E-mail is just so overwhelming, and I do a poor job of organizing it. Typically I don’t delete anything, wait a few month and dump everything into an archive folder and rely on my email search function (or my memory – yikes!) to find things. That system is not efficient and I frequently miss important tasks due to my lack of control over email. I will try be more efficient, and hopefully more productive, by clearing and deleting unnecessary e-mail clutter daily (yeah, right.) –>Does anyone have good suggestions for managing e-mail??

#2013Birds – the beginning.

6. Become a (better) birder. This resolution reflects the fact that the line between my professional life and my personal life is pretty blurry. I wish to be more knowledgable about birds because they are part of earth’s rich fabric that we call biodiversity and my research interests are about biodiversity. I also think that birds are lovely and fun to watch. Every year I try to be a better birder but it seems to fizzle out my mid-year. This year will be different because I will give myself a goal. I am quite obsessed with list-making, and by tracking all the bird species I see in a year provides me an opportunity to make another list, and will hopefully help me become a better birder. Want to join the fun? With twitter, use the hashtag #2013Birds. I think I will also experiment with i-naturalist to track the species count. So far this year? Blue jays, ~~Chipping sparrows~~ American tree sparrow, Black-eyed Juncos, American crows, and black-capped Chickadees (most of these in my own backyard).

Wish me luck! (I’ll keep you posted about successes and failures!)

Arthropod Ecology

Writings about arthropod ecology, arachnids & academia at McGill University

Category Archives: Arthropod research