Category: entomology

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A tiger in your back yard?

When we think of endangered animals, among the first things to come to mind may be creatures like rhinoceroses, tigers, or condors. Large animals, lots of press, and pressing concerns. There are an estimated 799 eastern black rhinos, ~400 Siberian tigers, and 237 California condors left in the wild. In some cases, as with these animals, their numbers have been reduced by human assaults of various sorts. In most cases there are plenty of ongoing issues, often related to habitat loss, that either keep populations in decline or which make recovery difficult.

But these animals and their attendant situations all seem pretty far away. Their distant geography lends itself to experiential distance as well. We hear about them, we see photographs and documentaries about them, but we will likely never have a chance to encounter them in the wild. Of course, even with geographical and experiential distance, concern is still warranted, and we might donate some money to one or another of these causes, or at least keep up with the issues via the news media. But beyond that, what can we do? The situations for these animals, and many others like them, may be dire, but we realistically can’t be present with them.

What if I told you that there is an animal in our own back yard (if you live in the Vancouver area) with population numbers and threats akin to – or perhaps worse than – those facing a Siberian tiger? What if I told you that, like a tiger, it is a ferocious predator?

What if I told you that it’s a spider?

Gnaphosa snohomish. Drawing by Robb Bennett, used with permission.

The animal that I’m talking about is the Georgia Basin bog spider (Gnaphosa snohomish). It is quite likely that you’ve never heard of it until now, and very likely that you have never seen it, even unintentionally. That is because although it lives in heavily populated southwestern British Columbia and the surrounding area, it is restricted to a few small patches of habitat where, even in such a major population centre, few people ever go. And because few people ever go to where it lives, those spots are often under pressure for development – “if no one uses that area presently, why shouldn’t we turn it into something ‘useful’?” goes the thinking.

Because of where it lives – as the name implies, in boggy wetlands – the Georgia Basin bog spider’s population numbers are not fully known. Thankfully, though, some people do go and look for this creature, and what we do know is that, indeed, the population levels and threats are likely similar to some of the bigger animals mentioned in the preamble. This is not a situation that many often consider to be a problem for spiders and insects, and perhaps that is because we know so little about so many of them.

One of the main problems for this spider is that humans don’t live in bogs, at least not while they remain in their boggy condition. We tend to either drain bogs for development, harvest their moss for other uses, or use their natural conditions to grow crops like cranberries. In some cases other development, such as roadways, can have draining and polluting impacts on nearby bogs. All of these factors, and others, mean that when humans and bogs meet, the bog loses, as do many of its denizens. The Georgia Basin bog spider in British Columbia’s Lower Mainland is one of those creatures currently on the losing side of that ledger.

In recent years some detailed work has been done on the Georgia Basin bog spider. You can find some of the most recent assessments of its status and coverage of its known natural history here and here. Both of those links are PDFs.

In a nutshell (you can find all of this information, and more, in those two PDFs):

  • The Georgia Basin bog spider has been found only at fifteen sites – seven in southwestern British Columbia, and eight in northwestern Washington state. Recent work has also detected the spider at Island View Beach in Canada.
  • Take a look at this aerial view of the Burnaby Marshlands. You can see at that link the level of pressure on the habitat there. That location was the Canadian site at which the greatest number of spiders were detected in a previous (1998) survey. There is good reason to believe that this population has been extirpated between that survey and now.
  • All of this means that the overall area of occupancy for the spider in Canada is roughly only about 16 km2.
  • This also means that the spider populations are extremely isolated from one another, limiting gene flow. It is thought that these spiders “balloon”, which is when young spiders cast a silk thread and catch breezes to disperse to new locations. Spiders have little control over where the wind takes them. So one can imagine that a ballooning Georgia Basin bog spider is pretty unlikely to land, by happenstance, in a suitable sphagnum bog within its current range, let alone survive to maturity to find and successfully mate with another Georgia Basin bog spider.
  • From collection records, it seems that the spider requires wet, and seemingly preferably, peat bog conditions.
  • Of the five sites in Canada with presumably established populations, four are at 3 meters or less above sea level. So besides impacts of human activity, there is a distinct risk of seawater inundation following a seismic event (i.e., a tsunami).
Gnaphosa snohomish male, photo courtesy Darren Copley, RBCM.

The Georgia Basin bog spider – just like tigers, rhinos, or condors – has a limited range, a limited number of appropriate habitats in that range, and is increasingly impacted by ongoing development and other pressures.

And it may live in your metaphorical (or literal!) back yard.

In other words, keep an eye out for the little things that live where you live. Just like the big things that live elsewhere, they have some important stories to tell.

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Thanks to Robb Bennett, Jennifer Heron, Darren Copley, Patrick Lilley, and Andrew Baylis for assistance with various aspects of this blog post.

This is a cross post from A Rocha Canada.

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Skiffs and shifts

Over the past few summers, I have been spending about a day a week (give or take) on the Crooked River just north of Prince George. This little river, just a few dozen kilometres in length, flows north from Summit Lake into McLeod Lake. Its source is just on the north side of the Arctic watershed, which in itself makes the river somewhat unique compared to the rivers just to the south. Its low-gradient, meandering nature, plus ample and fertile forest all around it make it a very rich habitat for birds, mammals, fish, and aquatic invertebrates. A quick kick sample of the river will bring up a screen writhing with all sorts of little creatures waiting to be discovered.

Part of the river is protected by a provincial park, but much of it is not. Even though there is copious logging activity (and the logging roads and bridges that go along with that), a major highway, and a rail line right alongside the river for part of its course, it is in great shape. But there is always a worry that cumulative impacts, or a substantial environmental accident along its banks could cause damage. The river is a real jewel, seemingly resilient, often overlooked by residents in the area, and potentially vulnerable to catastrophe. And it’s a place that has become important to me.

In previous summers one of my colleagues (Dr. Daniel Erasmus) and I, along with an undergraduate student (Claire), have sampled nymphs on the river, with a general focus on mayflies, but also collecting stoneflies and caddisflies. This year, in an effort to create a fairly complete checklist of the mayflies of the Crooked River, we sampled only adults. The nice thing about nymphs is that they are always there. The difficult thing is that they may be present in early (and hard-to-key) instars, or they may reside in hard-to-reach places in the channel. After substantial nymph collecting we decided that a focus this year on adults would potentially reveal a few species that we had missed, along with some further aspects of their natural history.

Our approach this summer was a combination of Malaise traps hung at the bank just over the water, and hand collecting. Malaise traps are not necessarily the best for mayflies as they don’t scuttle around too much after landing and so don’t always end up in the traps, but we had some success. Our best success though, it seems, was simple hand collecting. To do this we would enter the stream at several locations and would spend a cumulative hour of effort catching any emerging or egg-laying or otherwise flying and water-alighting mayflies that crossed our path. Often there were only two of us on the river, which meant about a half-hour of silence at each of our several sites. Silence, but for the sound of the water, or a kingfisher’s call, or a trout rising a few feet away (“darn, it took that mayfly on the water that I was about to collect”), or the grackle of the ravens that often greeted us at site CR2B. And the shush of a light summer breeze through the bank willows. So not-so-silent silence. But mind silence. And soul solace. The harmony of stillness.

That was a few months ago now, both temporally and metaphorically. Two nights ago we had our first skiff of snow here in Prince George. It is all melting now, but it is a reminder that we are soon to move from days of warm color to days of cool monochrome. On one hand that shift can be difficult for me and for others, not only because of the sudden change to sparseness on the landscape, but also, it seems, the concomitant increase in desk work and similar activities.

On the other hand, there are things to embrace about the shift as well, and embracing these can be helpful:

  • all of those mayflies need to be sorted, curated, and turned into tables and graphs. Each one, represents a singular moment in the past summer. A memory of the river. Claire is currently working on this as part of her thesis project and it’s exciting to think about what we are going to learn.
  • lots of other data from other projects; winter is the time where we get to learn to tell the stories of our summer data collection.
  • the ravens that visit me at my bus stop almost every morning during the winter.
  • my exercise regimen shifts from mainly outside to mainly inside. As a bit of a natural introvert (i.e., I don’t get charged up by crowds), this also means moving from a few passers-by to a zillion other people on the track at the gym. But that also means social interaction from time-to-time, or at least the presence of other humans. And that is as vital sometimes as the exercise.
  • the annual Entomological Society of Canada meeting, this year in lovely Montreal (and where I’ll have a poster up with some of our Crooked River caddisfly work), with plenty to learn about and colleagues and students to catch up with. And poutine.
  • in the winter semester I’ll be teaching three courses (yikes!) including my perennial favorite Animal Behaviour, and a new course for me that I’ve always wanted to teach, Invertebrate Zoology.
  • more community moments with family, friends, and colleagues while we spend more time indoors and in closer contact with each other.

Chris Buddle wrote (and videoed) a great discussion about not always being “fine”. For him and many others November can be a tough month. Personally, sometime around February is often my yearly nadir. I have found, though, that thinking ahead to that time in a mindful way can reduce the depth and, in some years, even make February a real time of hope as I see the transition to spring and the return of the light.

This year one of my plans is to think back to those moments of stillness on the Crooked River this past summer, to seek out quiet moments in the monochrome of the Prince George winter, to seek out family and friends as the winter deepens, to grab onto the good things that come with the season, and to look forward to a new spring and the rivers and forests that will still be there after they awaken from their blanket of snow.

 

 

Danie and Claire head off to collect from one of our Malaise traps on the Crooked River (upstream/downstream panorama at site CR2B).
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Book review: The Book of Beetles

The Book of Beetles: A Life-size Guide to Six Hundred of Nature’s Gems
Edited by Patrice Bouchard
Contributions by Patrice Bouchard, Yves Bousquet, Christopher Carlton, Maria Lourdes Chamorro, Hermes E. Escalona, Arthur V. Evans, Alexander Konstantinov, Richard A. B. Leschen, Stéphane Le Tirant, and Steven W. Lingafelter
2014, University of Chicago Press
656 pages, 2400 color plates
$55 (cloth), $33 (eBook)

Last autumn, while I was wandering around the poster presentations at the Entomological Society of Canada annual meeting in Saskatoon, I came across very inconspicuous display highlighting a book that was about to be released. Inconspicuous or not (and “display” might be a generous word to describe what simply amounted to a pile of handouts on a side table), it immediately caught my eye. And why wouldn’t it? The subject, beetles – in all of their glorious shapes, sizes, colors, and life histories – is always eye- and mind-catching. Upon returning home, I immediately pre-ordered it and received it from my local bookstore shortly after it was published. It has taken residence on the coffee table in our living room, and I have been enjoying it ever since.

The book is simply titled “The Book of Beetles” and is edited by Dr. Patrice Bouchard (Agriculture and Agri-Food Canada) with contributions by a number of experts. Much like “Snakes on a Plane”, the title tells you what it is about. But unlike that movie, this book is much more than its simple title. The idea of covering the full diversity of beetles sufficiently is, of course, a pipe dream. This book runs over 650 pages and covers 600 of the hundreds-of-thousands of known, not to mention the likely millions of more unknown, species of beetles. The full spread of beetle diversity is immense and, as is pointed out in a brand new (and open access!!) paper, “The beetle tree of life reveals that Coleoptera survived end-Permian mass extinction to diversify during the Cretaceous terrestrial revolution” by McKenna et al., “
(beetles) account for ∌25% of known species on Earth and ∌40% of insects”. To cover every known beetle species on earth would require well over 600 more of these volumes.

Also from McKenna et al.:

Curculionidae [snout and bark beetles, commonly referred to as weevils or “true” weevils] is the second most diverse family of metazoans (surpassed only by the rove beetle family Staphylinidae, which is older) with more than 51 000 named extant species in more than 4600 genera. Conservatively, it is estimated that there are more than 200 000 additional undescribed species of Curculionidae alone.

In other words, if we knew every single species of weevil extant today, we would need to compile more than 400 volumes of this size just to cover that one group within the beetles.

So the authors the The Book of Beetles were obviously required to complete the daunting task of choosing a mere 600 beetle species – a bit more than 0.1% of known beetle species – to highlight in this book.

In the introduction the authors set out their criteria for inclusion in this book. The authors chose among beetles that, variously:

  • are “scientifically compelling”
  • have “curious natural histories”
  • are “culturally significant”
  • are “economically important
  • are “rare and threatened”
  • are “physically impressive”

Again, certainly many, many other beetle species besides the chosen 600 met all of these criteria but could not be included. But I would argue that the editor and contributors did a fantastic job of selecting 600 compelling examples of these amazing insects that highlights a small, but still immense, range of their diversity.

Upon first encountering this large book (the cloth version, weighing in at 2.2 kg, is not one that is easily read in bed, but there is also an eBook option for those so inclined), the reader is immediately struck by the beauty of the jacket featuring an array of impressive insects surrounding the title. Remove the dust cover, and you will find three more gorgeous photographs of beetles on the front, spine, and back. These photographs all should simply whet your appetite for what you will find when you open the book.

The book begins with a short introduction to the volume followed by eight nicely illustrated chapters entitled “What is a beetle”, “Beetle classification”, “Evolution and diversity”, “Communication, reproduction, and development”, “Defense”, “Feeding behavior”, “Beetle conservation”, and “Beetles & society”. Each chapter is accessible for the non-expert, but engaging and full of enough detailed information to also keep career entomologists and expert naturalists interested. The chapters are short, ranging from about two to six pages each; and by p.30 the real meat of the book – the description of the 600 chosen beetle species – begins. The book, at this point, is divided up into four parts covering species from the Archostemata, the Myxophaga, the Adephaga, and the Polyphaga. The latter, of course, comprise by far the largest portion of the book

If you want to take a good look at what each species page entails, you can download a PDF sample of the book here.

Each species page contains information on one beetle species, so each open pair of pages features two species. From top to bottom each page has a generalized range map (entire world minus Antarctica mapped on each page) for the species; a table of generalized taxonomic and natural history information (family, subfamily, distribution, macrohabitat, microhabitat, feeding habits, and a note); a dorsolateral line drawing of the insect along with a note on the typical adult length (sometimes for both male and female if divergent); the species name in both italics and in all caps, along with the taxonomic authority and date; a paragraph on the natural history of the insect; a paragraph detailing related species of note; a photograph of the insect at actual size; a dorsal macro photograph, always of high quality; and a small figure heading next to the macro photograph with a bit more interesting natural history.

The level of detail in both the photographs and in the text is exceptional. For the photographs, you will have to look at the sample linked above to see what I mean. In terms of the text, each and every species is a joy to read about. For instance we learn about the cigarette beetle (Lasioderma serricorne; p.372) that specimens have been found in Tutankhamun’s tomb; and that the larvae of the Florida tortoise beetle (Hemisphaerota cyanea; p.555) build up strands of their own feces over their bodies to protect themselves from enemies. And on and on it goes, page after page in rich and amazing natural historical detail.

The book ends with several short appendices including a glossary, a classification of the Coleoptera, and a list of other beetle-based resources.

This is not the sort of book that most people would likely read through one page at a time front to back and then put away. Rather, it is a book that can be read much as one might open random drawers in an entomological collection, with the benefit of having a studied natural historian at your shoulder to tell you what you are looking at. In other words, this book is a sheer pleasure to read and to look at, and everyone will learn from it. It definitely belongs in the collection of every practicing entomologist or other naturalist who is interested in insects.

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Wharf borers

Some of the nicest things about the older entomological literature are the short papers that record interesting observations. To some extent these almost seem like the blog posts of that era – reasonably short and pithy with some useful information as well. I really enjoy reading these short accounts, in part because of the interesting natural history information that they contain, and in part because they are often rife with potential research questions. The reality, of course, is that I have neither the budget nor the time to follow up on 99.9% of what can be found in these accounts. Nobody does. But, if nothing else, reading these short notes is a good exercise in brain stretching.

N. melanura larva (PaDIL, CC-BY-3.0)

I recently came across one of these notes in the Journal of the Entomological Society of British Columbia. Since I edit this journal, I often end up browsing its pages, and this note by G.J. Spencer (1946) on wharf borers found in pilings in Vancouver caught my eye. It seems that Spencer was asked to take a look at some creatures that were found at the BC Sugar Refinery at the Port of Vancouver. The enquirer was worried that they were Teredo navalis, the naval shipworm. The shipworm is a mollusk, so undoubtedly Spencer was able to immediately identify that the samples were not shipworms but were, in fact, insect larvae. He identified them as Nacerdes melanura, the wharf borer.

Spencer, however, “(found) it hard to believe the details that accompanied (the specimens)”, and he indicates that he went immediately to the wharf. What were these details that initially had Spencer so incredulous? Well it seems that construction work was being done at the site, and the workers had uncovered some old pilings that had been driven about thirty years before. Prior to the pilings being driven, that part of the seafloor was filled with ash and soil. After the pilings were in place more fill was dumped on top of them, concrete was poured over that, and then some buildings were built on top of that foundation. The workers who Spencer encountered had been in the process of demolishing those buildings when they uncovered the old pilings and found the larvae. Spencer himself also dug larvae out of a “…thoroughly soggy piling in which the centre only was of firm though very wet wood.”

Assuming that the historical account received by Spencer at the worksite was correct, that means that the infestation had been in place for some decades with no possibility of later infestation once the concrete was poured. In way of further corroboration of this phenomenon Morris (1980) cites Laing (1936) who observed larvae in wood that had been encased in concrete for seven years. Spencer indicates two logical hypotheses that flow from observations such as these. First, that it is possible that the larvae were introduced to the pilings during initial construction, and the insects were able to complete multiple generations in the same material. Or, second, that it is possible that the larvae of this species can undergo very long diapause or at least very lengthy development when trapped in such a situation.

N. melanura adult (PaDIL, CC-BY-3.0)

Either of these possibilities is, of course, interesting. So I dug around a bit more to find out about these strange creatures. However it turns out that the literature is rather sparse. They don’t seem to be major structural pests – which likely explains the rather low amount of research – although they do get mention as pests of wooden archeological artifacts. It seems that people mainly notice them (and call pest control professionals) when large numbers of adults occasionally burst onto the scene, often in damp basements or, interestingly, in the vicinity of toilets. There is no doubt that they like seawater-saturated wood, and saltiness may explain their association with urine as well.

Wharf borers have been documented just about anywhere that humans live. Because they seem to prefer saltwater-soaked timber, they usually are found at marine port cities. But that is not always the case as they have also been found far inland, and a substantial distance from seaports. Their seemingly ubiquitous presence associated with human activity has led to some debate about where they originate, and it is fair to say that centuries of shipping them all over the world have certainly tangled up that problem. But perhaps it is the sort of problem that could be worked out by some population genetics sleuthing.

Some recent work has shown that the larvae maintain enzymes that enable them to break down some components of wood. However it was not clear if those enzymes were from the insect itself or derived from fungi or other microorganisms associated with the larvae. Other papers that I’ve linked in this blog post speculate on whether the insect is digesting wood directly or if it is relying on, or even ingesting, associated microorganisms. That same recent study established that the larval period of the lifecycle is at least reasonable substantial and went some way to determining that temperature may signal the maturing insect to move from one stage to the next.

So it seems that we are dealing with some extremely hardy insects. They can live in the undoubtedly hypoxic environment of water-saturated and rotting wood. Besides that, the water that they prefer to soak their surroundings also has a high salt content. Somehow they are able to make a nutritional living in rotting wood that has undoubtedly has most of its easily available nutrients flushed out of it. And to top it all off, there is good evidence that they can spend at least a few years, if not decades, trapped inside of rotting timbers without further access to the outside world. It’s no wonder that these creatures have found ways to hitch rides with humans all over the world and then have settled in with us – usually mainly hidden from our sight – for the long haul.

Wharf borers are truly amazing little creatures, ones that deserve some further research attention. There are a lot of great questions here, and many of them represent some pretty low-hanging fruit.

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Goldilocks conferences

Last week I, along with dozens of Canadian entomologists, was in beautiful Saskatoon, Saskatchewan at our annual Entomological Society of Canada/Entomological Society of Saskatchewan Joint Annual Meeting. I had a great time there. There were five talks from my research program (including one of my own). I was very proud of all of my students and postdocs, as they all gave great talks. One of them, Sharleen Balogh, won the President’s Prize for her talk. And UNBC’s very own Staffan Lindgren became President of the Society for the next year.

Besides all of that, I was able to visit with many colleagues and students. We were able to “talk shop” and discuss our ideas easily, almost like an ongoing, really large lab meeting. We had time to get to know each other a bit better as actual humans, not just another name on a co-author list. And we were treated to all sorts of inspiring and informative regular talks, symposium addresses, and poster presentations. By the end of the four days in Saskatoon, I was tired but also elated at the state of entomological research and teaching in Canada. Our discipline is in very good hands for the foreseeable future, and that makes me happy.

All of this got me thinking a bit more about conferences on my plane flight back (while trying to avoid a conversation about “chem trails” with an insistent fellow sitting next to me). I’ve been to some very large conferences with attendees numbering in the thousands. And I’ve been to some very small conferences with maybe 20 or 30 attendees. The ESC JAM is an order of magnitude smaller than the former and an order of magnitude larger than the latter – nestling right into a bit of a sweet spot, in my opinion.

I do truly appreciate the smaller conferences for a number of reasons. There are no concurrent sessions, so you never are forced to miss a talk. They are really great venues for early-stage students to present their work in a thoroughly non-threatening atmosphere. They are a great place to reconnect with your closest – geographically and often in terms of discipline – colleagues. On that latter point, in a discipline like entomology where many of the issues that we deal with are regional in nature, this aspect cannot be stated too strongly. Having some time to compare notes on regional conservation or pest issues in a semi-formal setting with regional colleagues is vital.

I also like the larger conferences, but not quite as much. And the fact that I haven’t been to a large conference in several years now is perhaps a bit of a testimony to my deeper current mindset. Large conferences have the advantage of having something for everyone. With thousands of attendees giving talks or posters over a three- or four-day period, there are also many – sometimes dozens – of concurrent sessions. Organizers have a ton of resources, and they can bring in big speakers and a great trade show. This means that no matter what, I can find talks and items of interest to me at large meetings. But it also means that I feel required to preschedule myself to such an extent that it is unlikely that I’ll just stumble into a talk (or remain in a session after the talks that I was interested in) that truly but accidentally blows my mind. Pure organization is key at a large conference, and that reduces spontaneity.

I also find that I’m often more prone to being “lonesome in a crowd” at large meetings because you have to be pretty lucky to meet someone you might know just in time for lunch or dinner with so many concurrent sessions going on. Again, this can be overcome with planning (“hey, let’s meet at the registration desk for lunch at noon on Tuesday”), but does not really allow for surprise meetings with known and yet-unknown colleagues.

Don’t get me wrong, I’m not opposed to large conferences. They are amazing events, and I have always benefited from being at them. But perhaps it’s my somewhat introverted tendencies that make me more comfortable at the small-to-medium-sized meetings. It’s at those venues that I find that I can see presentations that are both exactly relevant to my work and also tangentially interesting. I can easily meet with people who I know. I can meet a few who I didn’t know before. And I can make a gracious retreat when I’m feeling a bit tired of interacting.

Ultimately I suppose that each of us has a Goldilocks Zone for preferred meeting size. Mine generally matches what I experienced last week. Preferences, of course, will vary. And the benefits of all meeting sizes mean that we should all also step away from our personal Goldilocks Zone from time-to-time to experience meetings of all sorts.

(And a quick addendum: Thanks so much to the organizers of the ESC-ESS JAM 2014. Having been part of an organizing team in the past, I realize how much work that was. I hope that you all are feeling proud of the great work that you did, because that was an excellent meeting all around.)