Notes from the field: Yukon wildlife (Part 2)

Here is Part 2 from the “notes from the field” series  – an account of a recent field research trip to the Yukon.  Click here for Part 1. 

14 July, 11 PM, Rock River Campground, km 445 (Dempster Highway), Yukon

“Bag of spiders” – a nice haul of wolf spiders!

We have had a busy few days – we finally got some drier weather in Tombstone and Laura and Barb were able to do some collecting, and Crystal set some more traps.  We left Tombstone a couple of days ago to drive north, collecting en route.  We have seen some of the larger wildlife, including arctic fox, moose, and grizzly bears.   However, our sights were really set on the smaller wildlife: Barb was particularly impressed with the diversity of parasitic wasps at a place called “Windy Pass” – this area is known for hosting a lot of rare, Beringian species, and entomologists have collected at this locality for decades. We crossed the Arctic Circle yesterday, and the Rock River campground is nestled in a river valley just north of the Arctic Circle.  We are now officially in the Richardson Mountain range – the tundra habitats about 10 km north of this campground is one of the most beautiful places on the planet.  I feel very lucky and privileged to be here.

Although we had some more rain and cold weather yesterday, today was a perfect summer day at this latitude (i.e., it got just above 20C) – it was also a very windy day, which was bliss since higher winds mean that the incessant hordes of mosquitoes are kept at bay.  Fieldwork in the sub-arctic is quite challenging, in part because of the mosquitoes.

Self-portrait geared up for the biting flies.

We collected well into the NWT, getting all the way to the Peel River (located about 540 km up the Dempster).  Crystal found the most northern locality for Wyochernes asiaticus in the NWT and for that reason I will buy her a beer whenever we get back to civilization!   Unfortunately we have yet to find Katie’s wolf spider species – we have checked a few locations but have come up empty – there are certainly many other species of wolf spiders on the Tundra, but the ones we have collected have not been Pardosa glacialis.  Our team is a little anxious about this, as we only have a few more days at the Richardson Mountains before heading south.

We are now back in camp and it should be time to crawl into the tents.  At this latitude it is pretty difficult to think about going to sleep – it is light 24 hours a day, so it is hard to trick the body into thinking it is time for sleep.   It’s even harder to get to sleep knowing that Pardosa glacialis is out there…somewhere.

Stay tuned for Part 3, coming Friday…

 

Notes from the field: Yukon wildlife (Part 1)

This is the first of a three-part series that was originally published (as one article) in the McGill Reporter, as part of their “notes from the field” section – it is an account of my research trip to the  Yukon, back in July.  It is reproduced here, with permission.  For a different (yet complementary!) account of this field trip, see The Bug Geek’s blog posts, Part 1 and Part 2.

MSc student Katie Sim searching for wolf spiders in the Yukon, among fields of cottongrass

8 July 2012, 10 PM, The Westmark Hotel, Whitehorse Yukon

Our entomology research team has just arrived in Whitehorse in anticipation of our upcoming fieldwork in the Yukon.  I just returned to my room after enjoying a beer at the hotel bar where we completed our GIANT shopping list this evening. Tomorrow morning we are picking up our RV, and will be driving about 500 km NW of Whitehorse (on paved roads) before turning onto the Dempster Highway – this famous Yukon road is a dusty, gravel road that heads straight up towards the Northwest Territory, crossing the Arctic Circle, and taking you from boreal spruce forests in the south to sub-arctic tundra in the North.  The Dempster crosses the Yukon-Northwest Territory border at about kilometer 465, and then continues on to Inuvik.   It’s a big trip with few opportunities for groceries along the way.  We are all part of the Northern Biodiversity Program – a multi-University collaborative project about the diversity of insects and spiders in Canada’s North.   After months of planning, applying for research permits, and fine-tuning our methods, it is great to finally be here.  That being said, I worry that the excitement and anticipation will keep us too jittery to get a good night’s sleep tonight – too bad since after tonight, we’ll be sleeping in tents rather than hotel rooms!

10 July 2012, 3 PM, Tombstone Campground, km 72 (Dempster Highway), Yukon

We have made it up to the Tombstone mountain range, about 75 km up the Dempster Highway.  Unfortunately, the weather has not been cooperative, so we are stuck in the campground, huddling in a cook-shack with other travelers.  Most of the other campers are on vacation, so we are unusual since our trip is for research.  We are also unusual because unlike most visitors to this part of the world, we are NOT viewing large wildlife (bears, moose) but are instead spending our time searching for the tiny wildlife along the Dempster highway.

PhD student Crystal Ernst installing insect traps on the Yukon Tundra

Our team includes two graduate students from my laboratory, Crystal Ernst and Katie Sim.  Crystal has been setting out “pan traps” (yellow bowls) to collect ground-dwelling arthropods (i.e., insects, spiders).  Part of her PhD is about unraveling some of the complexities of arthropod-based food webs in the Arctic, and she is using these traps to collect critters that live on the tundra.  Thankfully, her work does not require good weather!  Katie is working on the population genetics of a high arctic wolf spider, Pardosa glacialis – and she needs some more specimens.  We know that the species occurs near the Yukon-NWT border (in the Richardson mountains), about 300 km north of us.  A post-doc, Dr. Laura Timms, is part of our team also – she studies plant-insect interactions in the North, and is focusing her research on insects that feed on Willow and Balsam Poplar trees.  Our final team member is Dr. Barb Sharanowski, an entomology professor from the University of Manitoba – she is collecting parasitic wasps, with a goal of better understanding their evolution and diversity in northern environments.  Unfortunately, Barb and Laura’s work is dependent on dry and warm weather, so they are hoping for good conditions!

I am here to find a small (< 4 mm) and curious Arachnid known as the “Arctic pseudoscorpion“.  Pseudoscorpions are relatives of other Arachnids, and resemble scorpions, but without a tail.  They are predators (of other invertebrates) that live in soil, leaf-litter, under bark, and under rocks.  The species Wyochernes asiaticus lives under rocks beside creeks and rivers in the Yukon.  It is a Beringian species, meaning it exists in North America in regions that were unglaciated during the last ice age, including many regions in the Yukon. The Dempster Highway travels directly through a lot of these regions.   I have previously collected this species in the Yukon, and on this trip, I am hoping to gather more specimens to further understand its full distribution, and to collect data about its biology and life-history.

This morning, despite the rain, our team traveled to a half-dozen streams further south from this campground, and we had great success in pseudoscorpion hunting!  Numerous specimens were found under rocks beside creeks, including females with their eggs held under their abdomen.

We are now drying out and I am about to finish preparing a seminar that our team will deliver tomorrow at the campsite.  The Tombstone Park staff are keen to have researchers discuss their work with the general public – it’s a nice opportunity to share our research stories with other people traveling the Dempster.  I am always thrilled that all types of audiences show keen interest and enthusiasm about insects and spiders.

Stay tuned…later this week will be Parts 2 and 3

A few reasons to study Arctic entomology

I’m a big fan of the Arctic, and I am on a mission to get more people interested in studying northern ecosystems.  In this post, I wanted to share some of the reasons why:

Poorly understood food-web

Arthropod-based food-webs in the Arctic are largely unknown.  This is a great research opportunity – our laboratory is working on this, and I am trying to put together an Arctic food-web from an arthropod perspective.    My PhD student Crystal Ernst is also thinking a lot about how high Arctic food webs are structured, and has some interesting ideas and thoughts in one of her previous posts.

Some of Crystal’s thinking about high arctic food-webs (reproduced here, with permission)

Look at all those spiders!

As most terrestrial Arctic biologists know, spiders are among the most common of the Arctic animals.  Our lab has documented that wolf spiders on the tundra occur at a high density, and the biology of Arctic wolf spiders is amazing.

An Arctic wolf spider (Lycosidae) female with egg sac, living on scree slopes of high elevation slopes, Bylot Island (Nunavut)

So, if you are an aspiring Arachnologist…head north!

Excellent base-line dat

Arctic Entomology has a long history of excellence.  Canada has been sending entomologist up to the Arctic for decades, perhaps most notably the Northern Insect Survey of the 1940s, 50s and 60s  – some information on that survey can be found here .  There has also been a lot of research at Lake Hazen, at the tip of Ellesmere Island (above 81 degrees N)  – earlier work reports over 200 species of Arthropods up at Hazen and a recent article in the Biological Survey of Canada’s newsletter, found here, does a nice job of summarizing the insect studies at Hazen (including our own work with the Northern Biodiversity Program).  These past studies provide an excellent baseline for current and future projects related to Arctic entomology – and you need a baseline to move forward.

The Arctic is changing

The Arctic is a very fragile and special environment, and one that is changing rapidly, in part because of climate change.  Permafrost is melting, tree-line is changing, glaciers are melting, and plant and animal assemblages are facing dramatic changes to their environments.  We must strive to document, quantify, and study the biology of life in the Arctic, and given the dominance of arthropods (i.e, diversity and abundance) in the north, they are a priority.  The time is NOW for Arctic entomology.

Biting flies:

If you have an interest in biting flies (and many people do, believe it or not!), the Arctic is the place for you.  Emerging from the tundra are thousands of flies, per hectare.  Many of them want your blood, and if they don’t get you during the day, they will be there at the end of the day, in your tent.

A host of biting flies, sitting between my tent and the tent fly. Just waiting for me to exit the tent and have a feast.

…and a couple of other reasons that have less to do with entomology:

Canada = Arctic 

We are a northern country, eh?  However, few of us spend much time in the “REAL” north.  From a biogeographic standpoint, we are a country without roads and people, but with a lot of boreal forest, tundra, and high arctic landscapes.

It is beautiful

The north is stunning; awesome landscapes, vistas that never end, big sky, large rivers, glaciers and mountains.

The stunning landscape of the Yukon Territory (Tombstone range)

Fieldwork Essentials: the resentment list

My last field trip up the Yukon’s Dempster Highway was amazing – in part because of the successful research, and also because of the amazing team of scientists that joined me in the field.  We were collaborative, collegial, productive and had loads of fun .  During this trip we established something called The Resentment List.  I think this list helped make the trip smooth, and I wanted to share the idea.

On our first day out of Whitehorse, I was commenting to my travel-mate, Dr. Barb Sharanowski, about how important it is to avoid resentment from building up during fieldwork – resentment leads to hurt feelings, and resentment can bubble dangerously under the surface and create a difficult working environment.  At our first roadside stop, the driver of the RV (post-doc Laura Timms,  traveling behind the car I was driving) commented on how inconsistent my driving was.  I flippantly answered “no way – I was using the cruise control” – This was all a big joke, and was funny since the roads were hilly and we were being ‘road biologists‘ (i.e., slowing down to stare at wildlife, landscapes, etc).  I joked about how we have to be careful that there isn’t resentment built up around my inconsistent driving, and then decided to start the resentment list.  Here’s a photo of the beginning of the list:

First page of the Resentment List: it reads “Laura, to Chris ‘driving was inconsistent’; Chris to Laura ‘it was on cruise ‘”

The rules of the resentment list were pretty simple:  anything that any team member perceives as something that could lead to resentment was written down during the day.  At the end of the day, sitting around the picnic table for dinner, we would share our resentment list(s).   The resentment list was mostly full of funny,  lighthearted items.  For example:  “The whole field team resents the Yukon for the weather we are receiving”, “We all resent how we smell” (i.e, after many days soaked in bug spray and lack of showers), or “The lack of grizzly bear sightings is leading to some Yukon resentment”.

Another page from the Resentment List, resenting the lack of nice weather, and the lack of bear sightings in the Yukon

I think, however, that this list actually helped dissolve any potential issues that could nag at us, and lead to more issues in the future.  For example, some of us were bothered by one team member’s giant sweep net pole that continually knocked us in the head every time we got into the car.  This was aired as a resentment, and we all laughed about it.  However, because this was discussed openly, that team member was aware of this little issue and was careful with the sweep-net from then onwards.  This may seem like a very small and insignificant issue, but those of you that have spent time in the field know how easily the small things can lead to bigger problems.    Here is another example – some of the team members were frustrated with me when I was obsessively e-mailing some photos over an extremely slow WIFI connection – it took way too long and we could have been doing fieldwork instead – this was aired on the resentment list, and this transparent process was an effective way for me to realize what I had done.  It helped.

So… next time you are heading off to do fieldwork – consider starting your own resentment list!  Heck, you may even find a use for this idea in your laboratory (…or your home..with your partner, room-mates, or family members..?).  Try it out, and please let me know if it works.

The resentment list did help our team – look how happy we are!

The happy “road biologists”

Successful Pseudoscorpion Hunting in the Yukon

The Arctic Pseudoscorpion Wyochernes asiaticus

I am heading back home after a simply amazing field trip to the Yukon Territory. As mentioned in a previous post, one of the goals of the trip was to collect more specimens of an Arctic pseudoscorpion Wyochernes asiaticus (Family Chernetidae) – a Beringian species known from Siberia, Tibet, and the Yukon. This species survived the last great glaciation event in North America by living in unglaciated regions of the northwest, including parts of the Yukon. In 2008 I had collected this species under rocks beside high elevation and high latitude creeks and rivers in a few locations in the Yukon. On this trip, my goal was to collect more specimens to further assess the distribution of this Beringian species, and to gather more life-history information including estimates of size and fecundity. Because of the relative rarity of pseudoscorpions, few data exist that describe life-history parameters of these arachnids.

Despite some rather wet and cold weather for a lot of the trip, the pseudoscorpion collecting was completely successful – we were able to collect hundreds of specimens, from the south end of the Dempster Highway (approximate latitude 64.3 degrees N) all the way up into the Northwest Territories (>67 degrees N). We collected specimens under rocks in more boreal regions, as well as the upper headwaters of high elevation creeks – some of these less than a metre wide. Here is an example of one of these northern, high elevation creeks in the Northwest Territories, just beyond the Yukon-NWT border:

An Arctic, high-elevation stream in the Northwest Territories: pseudoscorprion country!

To give you some idea of the ease of collecting, here is an example of what you might find when flipping over rocks beside the creeks:

Several Wyochernes asiaticus (Pseudoscorpiones) females (with yellow eggs visible)

I was also able to capture some video of these pseudoscorpions – as far as I am aware, Wyochernes has never before been videotaped, so this is the FIRST EVER movie of this species!

Our larger research goals included more than pseudoscorpion colleting, and I was in the Yukon with a wonderful team of scientists, including my graduate students Crystal Ernst, Katie Sim, a post-doctoral researcher Dr. Laura Timms, and an entomology professor from the University of Manitoba, Dr. Barb Sharanowski. We all had different objectives and goals for the Yukon trip, and over the next couple of weeks. I will post some more research stories from this field-work to give a sense of the scope of our research efforts in the Yukon.

The research team at the Arctic circle (Laura, Katie, Crystal, Barb & Chris)

Hunting Pseudoscorpions in the Yukon

In four days I head off for two weeks of field work in the Yukon.  I’ve written about this stunning place before, and my student Crystal also posted about the upcoming adventure.  Our time will be spent doing some final collections as part of the Northern Biodiversity Program, and I will also be hunting pseudoscorpions.

A selection of Pseudoscorpions

Although I have a fondness for harvestmen and spiders, pseudoscropions are truly fascinating,  and the most curious of the Arachnids.  They are small arachnids ( most are < 5 mm in length) that resemble scorpions, minus the ‘tail’.  They are found around the world (except Antarctica), and although only a few thousand described species, globally, they are morphologically diverse, and beautiful.  Pseudoscorpions are predators of other small invertebrates, and they typically live within leaf-little, soil, tundra or other substrates on the ground.  They are also phoretic, and sometimes found hanging onto the legs or bodies of other insects.   To learn all about the biology of pseudoscorpions, I recommend reading  Weygoldt’s book.

C. Buddle venturing towards Sheep Creek, Yukon, to search for pseudoscropions

I have a longstanding interest in Pseudoscopions from Canada, and keen to obtain more records to increase the distribution notes for Canada’s fauna.  My trip to the Yukon next week will include searching for a fascinating species: Wyochernes asiaticus.    In North America, this species was described as W. arcticus by William Muchmore in 1990, and is considered the most northern pseudoscorpion on this continent.  Muchmore’s paper was based on 6 specimens collected under rocks beside Sheep Creek, Yukon.  When I was in the Yukon in 2008, I went to Sheep Creek, looked under rocks beside the creek and there were hundreds of specimens to be found:

A Wyochernes (Chernetidae) pseudoscorpion, under rocks at Sheep Creek

Later, Muchmore determined that W. arcticus is the same as a species from Asia (W. asiaticus).   So… those of you that know your glacial history are aware that sections of the Yukon remained unglaciated during the last ice age. Quite a number of taxa have been found in that region of the Yukon whose closest relatives are from Siberia and other parts of Asia. They are relicts of the past, and labeled ‘Beringian’ species because of the Beringian land bridge that used to join North America to Asia.    That tiny pseudoscorpion is a perfect and stunning example of a Beringian species – it is known only from Siberia, Mongolia, possibly Tibet, and from a few localities in the Yukon.

You can probably anticipate my excitement – when I was last in the Yukon almost all the dry creek beds up the Dempster Highway hosted Wyochernes asiaticus.  I am most eager to collect more.  I will be collecting them to test some life-history theories,  verify distribution records, and see just how far north this species can be found.  NOTE:  IF YOU ARE THINKING OF DOING YOUR OWN COLLECTIONS IN ARCTIC REGIONS, INCLUDING THE YUKON, YOU NEED A SCIENTIFIC PERMIT TO DO SO.  You cannot collect in these parts of the world without authorization.  This makes sense-the beauty of the North cannot be taken for granted and needs to be studied with caution:

The Yukon.

As you can guess, the Dempster highway is a rather isolated and remote region.  I will not likely be posting again until after my return. Later in July, I do hope to share some more research stories with you…and I can pretty much guarantee there will be discussions about pseudoscorpions!

References: 

Buddle, C.M. 2010. Photographic key to the Pseudoscorpions of Canada and the adjacent USA. Canadian Journal of Arthropod Identification No. 10, 03 February 2010, available online at http://www.biology.ualberta.ca/bsc/ejournal/b_10/b_10.htmldoi:10.3752/cjai.2010.10.

Muchmore, W.B. (1990). A pseudoscorpion from arctic Canada (Pseudoscorpionida, Chernetidae) Canadian Journal of Zoology, 68 (2), 389-390 DOI: 10.1139/z90-055

Muchmore, W.B. (1996). On the occurrence of Wyochernes in Asia (Pseudoscorpionida: Chernetidae).  Bulletin of the British Arachnological Society 10(6): 215-217.  Link

Life History of Arctic Wolf Spiders: Part 1

For those of you who follow my blog, you will notice I’m somewhat obsessed with the Arctic – in part because of our large Northern Biodiversity Program, but also because it’s an ideal  system for studying the ecology of arthropods.    It also doesn’t hurt that the Arctic is a beautiful place to work!

The northern Yukon landscape: spider habitat

I am very excited to write about the latest paper published from our laboratory, titled Life history of tundra-dwelling wolf spiders (Araneae: Lycosidae) from the Yukon Territory, Canada.  This has just recently been published in the Canadian Journal of Zoology, with Dr. Joseph Bowden as the lead author.  Dr. Bowden graduate from my laboratory just over a year ago, and is now living in California with his family.  Although the climate is somewhat warmer in California compared to the Yukon, he’s still actively working on research related to the biology of Arctic arthropods.   Dr. Bowden was a terrific student in my laboratory, and has already published some work about the community ecology of Arctic spiders: he has one paper in the journal Arctic and another in Ecoscience.

Dr. Joseph Bowden, working in the Yukon and ready for the biting flies!

In the CJZ paper, Joseph studied three species of tundra-dwelling  wolf spiders (family Lycosidae) and asked whether body size or condition better explained variation in fecundity and relative reproductive effort (defined as the ratio of female body mass to clutch mass).  He also tested whether  a trade-off exists between investment in offspring size and number.  The field work for this research was really enjoyable, as it involved collecting spiders by visual surveys and dry pitfall traps – after collection, Joseph set up a laboratory in a local campground shelter to do measurements on the species:

Dr. Joseph Bowden in a Northern “laboratory”

One of the main findings was that body size explained well the variation in offspring number.  Stated another way, larger female wolf spiders produced more eggs, a finding well supported in the literature.   A second main finding was that females with a lower condition allocated relatively more to offspring production than did females in better condition. This makes some sense – if the going is tough (i.e., poor condition), the females primary objective (from a fitness perspective) is to invest in offspring.  A third key finding was that  we found a negative relationships between egg size and number.    These trade-offs may in part be because of variation in resource availability at some of the study sites in the Yukon tundra.

An Arctic Pardosa (Lycosidae) female, with egg sac

Joseph also calculated tundra wolf spider densities.  Here’s the text of the CJZ paper that describes the methods (straightforward but time consuming):

Densities of the three focal species were estimated using a ring of hard plastic measuring 1.13 m in diameter (1 m x 1 m area) and about 12 cm high. The ring was haphazardly and firmly placed on the tundra surface in each site and all wolf spiders collected inside the ring were identified and counted. This protocol was adapted from Buddle (2000).

Results? Well… the most common species Pardosa  lapponica averaged about 0.4 spiders per square metre.  Some simple calculations will tell you just how common wolf spiders are on the Tundra:  4000 wolf spiders per hectare.  Don’t forget – wolf spiders are only part of the Arachno-fauna in the Arctic.  With confidence, this estimate of 4000 spiders per hectare represents a minimum.  There are a LOT of Arachnids living on the tundra!

In sum, this paper by Joseph is about studying some good old-fashioned natural history of a fascinating group of animals.  The methods are straightforward, but the findings are significant.  It’s pretty difficult to progress in ecology without a deep understanding of a species’ biology and life-history.  Life-history studies are the cornerstone of biology, and I’m thrilled that Joseph recognized that fact and did this research on Arctic wolf spiders.

    You will see that this post is titled Part 1:  some more work will hopefully be published soon – stay tuned for Part 2…

References

Bowden, J., & Buddle, C. (2012). Life history of tundra-dwelling wolf spiders (Araneae: Lycosidae) from the Yukon Territory, Canada Canadian Journal of Zoology, 90 (6), 714-721 DOI: 10.1139/z2012-038

Bowden, J., & Buddle, C. (2010). Determinants of Ground-Dwelling Spider Assemblages at a Regional Scale in the Yukon Territory, Canada Ecoscience, 17 (3), 287-297 DOI: 10.2980/17-3-3308

Buddle, C. (2000). LIFE HISTORY OF PARDOSA MOESTA AND PARDOSA MACKENZIANA (ARANEAE, LYCOSIDAE) IN CENTRAL ALBERTA, CANADA Journal of Arachnology, 28 (3), 319-328 DOI: 10.1636/0161-8202(2000)028[0319:LHOPMA]2.0.CO;2

Bowden, J. & Buddle, C. (2010). Spider assemblages across elevational and latitudinal gradients in the Yukon Territory, Canada.  Arctic 63(3): 261-272 http://arctic.synergiesprairies.ca/arctic/index.php/arctic/article/view/1490

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Help Build an Arctic Food Web

A couple of weeks ago I was fortunate to be able to attend a workshop about monitoring terrestrial arthropod biodiversity in the Arctic. In advance of that workshop, I offered to prepare a draft of a food-web that was ‘Arthropod-centric’.  There are many ways to build a food-web, and my first draft was focused on who eats whom.  In other words, an arrow depicting interactions would indicate predation (loosely defined).  An alternative would be to focus on energy moving through the system (i.e., the arrow would move ‘up’ from trophic level to trophic level, to indicate a transfer of energy).

Putting this together is a challenging, yet rewarding process.   I consulted with many of my colleagues with expertise in Arctic systems (including the folks involved with our Northern Biodiversity Program), and I am struggling to find the right balance between generality and specificity.  Here’s a portion of the (draft) food-web, showing some of the interactions:

Part of an Arctic Food Web, with an Arthropod Focus

When working on this food web, some interesting generalities are emerging: First, the overall dominance of Diptera (flies).  This is certainly because they do everything (e.g., decomposers, pollinators, blood-feeders) and they are very diverse.   Second,  arthropods are integrators – meaning they connect different processes, and they bridge different systems (aquatic/terrestrial).  Third,  highly valued vertebrates  (and humans!) depend on arthropods (and/or are affected by them).

Does all of this pique your interest?  Want to help? Together with colleagues, I am seeking help as this food-web develops.  Send me an e-mail or drop a comment on this post and think about some of these questions and provide some feedback if you are so inclined:

….what interactions do you think are important in the Arctic, from an arthropod perspective?

….how can the interactions between vertebrates and invertebrates best be depicted?

….what interactions between humans and arthropods need to be included? (other than biting flies – that one is pretty obvious!)

….what ecological processes should be included in an Arctic food-web? 

There are other Arctic food-webs out there.   The Bear Island food-web is probably the best one that focuses on Arctic arthropods.  If you’ve not seen it, the paper by Ian Hodkinson and Stephen Coulson (2004) is worth a look.   That food-web is more specific than the one I am working on (it should be since it’s focused on a specific location and it can be because a lot of research has occurred there!).   I really like one of the last sentences in their paper: ...the Svalbard high Arctic terrestrial food web is far more complex than has previously been appreciated but further sections remain to be resolved.  Indeed!  I would argue that we need to develop these kind of specific food-webs from other locations in the Arctic, but to get there, we also need a general, broad overview that encapsulates the overall role and importance of Arthropods to the Arctic.  Hence the development of a general food web.

I’ll finish with some thoughts about using this blog as a platform for generating and refining ideas about this food web.  Last year I had a long discussion with my PhD student Crystal Ernst (aka the Bug Geek) about the use of social media in the creative thinking process.   Some parts of the discussion we had showed up in one of her posts about the role of social media in science.  There’s a nice quote in that post that really hits the nail on the head:

Social media is just another kind of “hallway talk…in a really, really, long hallway”. (Crystal attributes part of that quote to another fine blogger, Bug Girl)

Social media can be used effectively as a platform for soliciting feedback and generating ideas about science, including specific projects such as building a food-web diagram.   At this stage, I admit that I’m not ready to put the entire draft food-web in this post – it’s far too incomplete.  However, it is the perfect time to ask for help, and solicit ideas.

….I welcome your feedback.

Reference

D. Hodkinson, I., & J. Coulson, S. (2004). Are high Arctic terrestrial food chains really that simple? – The Bear Island food web revisited Oikos, 106 (2), 427-431 DOI: 10.1111/j.0030-1299.2004.13091.x

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Opening an ecological black box: entomopathogenic fungi in the Arctic

While visiting Alaska last week, I had the pleasure of meeting Niels M. Schmidt.  He is a community ecologist (from Aarhus University, Denmark), who studies Arctic sytems and he is one of the key people behind the Zackenberg Research Station in Greenland.   He told me about one of his recently published papers (authored by Nicolai V. Meyling, Niels M. Schmidt, and Jørgen Eilenberg) titled “Occurrence and diversity of fungal entomopathogens in soils of low and high Arctic Greenland” (published in Polar Biology).

An ecological black box: the tundra

By definition (from Wikipediaentomopathogenic fungi act as parasites of insects – these fungi can kill, or seriously disable insects.  I was amazed at this paper because I have never given much thought to fungal entomopathogens in the Arctic (despite knowing their prevalence in other ecosystems).    Could these fungi be ecologically important in Arctic?  I think Arctic community ecology has been seriously understudied, and we know little about what drives the relative abundance of species.  From an arthropod perspective, we know that some birds depend  on Arthropods for food (e.g. see Holmes 1966), and that flies are important nuisance pests to large mammals (e.g., Witter et al. 2012), but I would argue that most ecological interactions in the Arctic involving arthropods (and their relative importance) remain a mystery.   I could not even speculate on the role of fungal entomopathogens in the Arctic.  This is one of those feared ‘black boxes in ecology’:  probably there, possibly important, likely complex, but knowledge is seriously lacking. 

So along comes this paper: Meyling et al.  took soil samples from locations in the high and low Arctic (i.e., including Zackenberg, at about 74.5 degrees N), and they returned the samples to their laboratory in Denmark.   In their lab, the authors allowed live insects (using Lepidoptera [Pyralidae)] and Coleoptera [Tenebrionidae]) to be exposed to their samples, and they checked regularly for mortality: “...cadavers were rinsed in water, incubated in moist containers and monitored for the emergence of fungi“.  Any fungi that emerged from the (dead) host were identified.

The results: they identified five species of fungal entomopathogens (all in the division Ascomycota).  As the authors state in the start of their discussion “This study is the first to document fungal entomopathogens in soils from Greenland at both low and high Arctic sites. Furthermore, the use of in vivo isolation with living insect baits explicitly documented pathogenicity to these insects.”

Could this Arctic Weevil die from a fungal infection?

The black box has been opened:  indeed, fungal entomopathogens are in the high and low Arctic of Greenland, and are therefore likely in the high and low Arctic around the globe.  These fungi probably play a role in arthropod mortality in these systems, but this remains completely understudied.  As the authors point out, given the tight relationship between fungi and temperature, what effect could a changing climate have on these fungal entomopathogens?   This is potentially very important, as increased mortality of insects by fungi could trickle all the way up the food web…  I think we need to get more mycologists into the Arctic, and we must work to properly articulate high Arctic food webs with all the black boxes opened wide. 

References:

Holmes, R. (1966). Feeding Ecology of the Red-Backed Sandpiper (Calidris Alpina) in Arctic Alaska Ecology, 47 (1) DOI: 10.2307/1935742

Meyling, N., Schmidt, N., & Eilenberg, J. (2012). Occurrence and diversity of fungal entomopathogens in soils of low and high Arctic Greenland Polar Biology DOI: 10.1007/s00300-012-1183-6

Witter, L., Johnson, C., Croft, B., Gunn, A., & Gillingham, M. (2012). Behavioural trade-offs in response to external stimuli: time allocation of an Arctic ungulate during varying intensities of harassment by parasitic flies Journal of Animal Ecology, 81 (1), 284-295 DOI: 10.1111/j.1365-2656.2011.01905.x

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Holistic views of ecosystems: linking salmon and butterflies

Beautiful Anchorage, Alaska

I’ve spent most of my week in beautiful Anchorage, Alaska.  I was attending a workshop that brought together scientists from Northern countries to discuss an Arctic Terrestrial Biodiversity Monitoring Plan. The goal of this ambitious plan is to include all key taxa, include all northern countries, and find ways to standardize methods and harmonize data.   There were a half dozen bird experts around the table, numerous experts on Arctic vegetation, a large contingent of mammal experts, and one arthropod expert (me).  This is a situation I have been in before, and will be in again in the future – largely because arthropods are not “charismatic” nor do they typically fall into management plans.  Regardless, I welcomed the opportunity to discuss ways that Arthropods can and should fit into large-scale, and long-term monitoring plans in the Arctic (there are, by the way, some tremendous arthropod monitoring programs underway – the Zackenberg research station in Greenland, for example, has been collecting arthropods using standardized protocols for almost 20 years)

The workshop was exciting, challenging, motivating, and overall a wonderful opportunity to discuss the interdisciplinary concept of biodiversity monitoring.   A great example of an interdisciplinary approach was a presentation we heard about using traditional knowledge to understand the Natural Indicators of the Salmon run in the Yukon River, a river that drains out to the ocean in Alaska. This was organized/facilitated by the Yukon River Drainage Fisheries Association.  This presentation highlighted a project where Elders were asked about what helped them understand the Salmon run in the river – a critically important process for people living in this part of Alaska.  I was amazed to hear that for some Elders, the appearance and activity of certain species of butterflies (and sometimes biting flies) was one of the indicators that was used to predict when the Salmon would run.

An Arctic Butterfly

Yes, you read correctly: Butterfly activity indicates the Salmon run.   The claim that activity of insects relates to the Salmon run is not a direct connection as the insect activity was considered as a “Correlative indicator”.  The observation is that when certain insects appeared and were active, so were Salmon, hence the correlation.  This does make some biological sense as many of the environmental factors affecting butterflies are probably also important to salmon.

The Yukon River Drainage Association went on help to produce a children’s book titled When Will the Salmon Come?. This is a richly illustrated, beautiful book that discusses all the Natural Indicators that Elders use to know when Salmon will appear on the river, and the insect activity is highlighted.   A children’s book is a wonderful way to connect with a broad audience.

When will the salmon come? (the book cover)

Being a skeptical scientist, I went and searched the literature for anything ‘published’ on the topic of Salmon and butterflies, and I could not find anything.  This does NOT mean it’s not a real and important observation. It means that it is a truly fascinating and curious correlation that was observed by Elders living close to the river, and by people who likely approach nature from a holistic standpoint.  I need to do this more; we all need to do this more. Natural systems are interdisciplinary yet we often study them in silos, defined by a specific taxon or system.

In sum, I was most pleased to be the lone entomologist in a large interdisciplinary workshop  about biodiversity monitoring in the fragile Arctic – my horizons were certainly broadened.  The story of butterflies and salmon made me take a step back and consider how different groups of people can bring different perspectives and all are equally valid.  In other words, keep an open mind, and think of this story when you see some butterflies passing by…they could be telling you an important story – you just have to listen.