Trophic cascades in fragmented forests

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

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

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

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

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

Dorothy Maguire, working in a forest fragment.

Dorothy Maguire, working in a forest fragment.

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

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

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

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

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

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

Reference:

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

The effect of insecticides on jumping spider personalities

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

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

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

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

Screen Shot 2013-11-26 at 3.34.45 PM

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

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

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

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

Reference

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

Arthropod Ecology Mission Statement

Last week, during our laboratory meeting, we worked to develop a laboratory mission statement. My real inspiration for this came from my friend and colleague Elena Bennett – she also got me connected to Jessica Hellmann’s excellent post on the topic.  A mission statement is really just a way to clearly define who we are, what we do, and why we do the sorts of things that we do. From a research laboratory’s point of view, the goal of the exercise is (in part) to help all members of the laboratory feel part of something bigger. Something that has broad relevance to a community that extends far beyond the walls of our institution, and far beyond the boundaries of our own specific research projects.

As Jessica states clearly in her post, a Mission Statement  “…is a description of the purpose for your organization, primarily as it now is and/or will be within the next few years. A good mission statement should accurately explain why your organization exists and what it hopes to achieve in the near future. It articulates the organization’s essential nature, its values, and its work. The statement should resonate with the people working in and for the organization, as well as with the different constituencies that the organization hopes to affect. It must express the organization’s purpose in a way that inspires commitment, innovation, and courage.”.  A mission statement should be short, easily remembered, jargon-free, proactive, and readable to people outside of our organization.

Here’s what we did to come up with our (draft) statement:

1) We each wrote down a few words or a short sentence on an index card. We tried to write things that we felt described what the laboratory does in a broader sense (i.e. beyond our own specific interests). Here’s an example:

Screen Shot 2013-10-09 at 10.04.24 AM

2) We mixed up these cards and each person took someone else’s card. We then went around the table and read what was on the cards. This allowed us a terrific jumping off point for the discussion and generated the necessary words and ideas.

3) The ‘scribe’ (in this case, it was me) wrote down each descriptive word (in our case, things like ‘arthropods‘, ‘human disturbance‘, ‘biodiversity‘ came up a lot), and as a group, we wrote down some verbs to help us think about the ‘action’ that we take with the things we do. Here, verbs like ‘explore‘, ‘quantify‘, ‘share’ came up a lot.

4) We wrote the mission statement – in two parts. (a) We tried to provide a few sentence of context, and to ground our laboratory in the ‘why‘ and the ‘what‘; (b) We wrote a few sentence of ‘how‘ we do our research.

5) Edit, edit, edit. This was done during the lab meeting, but also over email

Here’s the end result:

Mission Statement:

Arthropods (insects, spiders and their relatives) comprise most of the known biodiversity on the planet. Human activities are rapidly changing our environment, from climate change to landscape fragmentation and urbanization, with unknown consequences for local and global biodiversity. Arthropods have profound effects on ecosystem function, human health, goods and services, and culture. Our well-being is connected to this “smaller majority”, yet we know little about where they live, what they do, and how their diversity is changing. In our laboratory we: 1) Quantify patterns of terrestrial arthropod biodiversity across a suite of ecosystems, over a range of spatial and temporal scales; 2) Explore how arthropods respond to and are affected by human-induced environmental changes; 3) Investigate the interaction between arthropods and ecological processes; 4) Share our knowledge, ideas, and passion about arthropods.

How did we do? We would love your feedback on this.

Here are a few thoughts and reflections:

  • This was a very worthwhile process – it was an amazing discussion and gave as opportunity to really delve into areas that were well beyond our individual research interests.
  • I have always believed that ‘patterns in terrestrial arthropod biodiversity’ was really what I spend my research time thinking about; it’s good that the collaborative process of developing a mission statement ended up reflecting that!
  • Any specific habitat (e.g., canopy systems, the Arctic), or even any type of arthropod (e.g., beetles, spiders) never remained in our final mission statement. This is terrific, and shows well that the laboratory has diverse interests, but more importantly, that we encourage research in different places and with different model taxa.
  • Yes, jargon remains. This is difficult. We agreed, as a laboratory, that our mission statement would be aimed at a ‘scientifically literate’ audience.
  • I’m an ecologists and we do ecology, yet that word did not end up in the final product. Curious.
  • We ALL agreed about the importance of ‘sharing’ and engagement with a broader audience -many of us do various kinds of outreach, from blogs and tweets to volunteering to talk about insects in local elementary schools. I was extremely pleased and proud that our laboratory sees this is a core activity.

This process if far from over: the next step is a “Vision Statement“. As Jessica points out, a Mission statement is more about what we “do” and why, whereas a Vision Statement “...looks at least five years into the future and defines a future state. It is an articulation of a world that the organization and people are working toward, not what is expected to happen now“. Ok, that’s a task for a future lab meeting!

(BIG thanks to my amazing laboratory for helping develop a mission statement)

Lunch in the tree-tops for the birds and the bugs

A few weeks ago, our laboratory published a paper in PeerJ (an open-access journal) titled “Vertical heterogeneity in predation pressure in a temperate forest canopy“. This work resulted from a project by former Master’s student Kathleen Aikens. She graduated a little while ago, and although we published one of her thesis chapters in 2012, it took another year to get this paper out, in part because Kathleen and I both become too busy.  Thankfully, post-doc Dr. Laura Timms agreed to help us finish up the paper, and she worked with me and Kathleen to re-analyze the data, re-write some sections, and whip it into shape.

As is now traditional for my laboratory, here’s a plain-language summary of the paper:

Tree canopies, including those in deciduous forests in southern Quebec, are important for many different animals, including insects and spiders. These small, marvelous creatures crawl up and down trees with regularity, feed upon the leaves of trees, feed upon each other, and are food for animals such as birds and bats. Past research has shown that many species of insects and spiders live in tree canopies, and in general, more insects and spiders are found closer to the ground compared to the very tops of the trees. This makes sense, since deciduous tree canopies often need to be recolonized each spring, and tree canopies are relatively harsh environments – they are windy, hot, and often-dry places as compared to the forest floor.  What we don’t know, however, is whether the insects and spiders avoid the tree canopies because they may be eaten more frequently in the canopy as compared to the understory. The objective of this research was to test this question directly, and find out whether insects and spiders are arranging themselves, vertically, because predators may be preferentially feeding on them along this vertical gradient. This is a very important area of study since biodiversity is highly valued and important in forests, but we cannot fully appreciate the status of this diversity without discovering what controls it.

image

Our mobile aerial lift platform. TO THE CANOPY!

We did this work by using two experiments that involved manipulating different factors so we could get at our question in the most direct way possible. In the first experiment, we made ‘cages’ out of chicken wire and enclosed branches of sugar maple trees in the cages. We did this at the ground level all the way to the tops of trees, using a ‘mobile aerial lift platform’. These cages acted to keep out large predators, such as birds, but allowed insects and spiders to live normally on the vegetation. We counted, identified, and tracked the insects and spiders both within these cages, and in adjacent branches that did not have cages (the ‘control’). By comparing the control to the cage, we could find out whether feeding activity by larger vertebrate predators affected insects and spiders, and whether this differed when comparing the ground to the top of the trees. In the second experiment, we used small pins and attached live mealy worms (larvae of beetles) to the trunks of trees, and we did this in the understory all the way up to the canopy. We watched what happened to these mealy worms, and compared what happened during the day and overnight. This is called a ‘bait trial’, and let us figure out what sort of predators are out there in the environment, and in our case, whether they fed more often in the canopy compared to the ground-level. This second experiment was designed for seeing the effects of insect and spider predators along a vertical gradient whereas the first experiment was focused more on vertebrate predators (e.g., birds).

image

Munch munch. Carpenter ants feeding on mealworms.

Our results from the first experiment showed that the cages had an effect: more insects and spiders were found when they were protected from predation by birds. Birds are playing a big role in forest canopies: they are feeding on insects and spiders, and in the absence of vertebrate predators, you might speculate more insects and spiders would occupy trees. Our second experiment showed that ants were important predators along the tree trunks, and overall, the most invertebrate predators were found in the lower canopy. Both experiments, together, confirmed that the understory contained the most insects and spiders, and was also the place with the highest amount of predation pressure.  The take-home message is that there is an effect of predation on insects and spiders in deciduous forests, and this effect changes if you are in the understory as compared to the top of the canopy. We also learned and confirmed that insects and spiders remain a key element of a ‘whole tree’ food web that includes vertebrates such as birds, and that predators in trees tend to feed on insects and spiders along a gradient. Where there is more food, there is more predation pressure! Our work was unique and novel because this is the first time a study of predation pressure was done along a vertical gradient in deciduous forests. It will help better guide our understanding of forest biodiversity, and the processes that govern this diversity.

A more detailed discussion of this work is posted on the PeerJ blog.

Arctic reflections (Part 2)

I started a post last week about my recent field trip to the Arctic – I was situated in Cambridge Bay (Nunavut) for a week, and here are a few more reflections from that trip.

Screen Shot 2013-08-14 at 9.11.42 PM

Wildlife

Walking across the tundra brings sights of circling rough-legged hawks and the sounds of jaegers. We were able to find spots where the hawks like to sit (at higher elevations, on a pile of rocks and boulders). The vegetation is particularly rich under these perches, as the nutrient inputs are very high! We could also find feathers, and pellets – these pellets are a tidy package – a mass that represents the undigested parts of a bird’s food, regurgitated. These pellets can be dissected and you can find the tiny bones of small mammals. While in Cambridge Bay it was a particularly good year for lemmings, and thus a particularly good year for hawks, and snowy owls. Each day on the tundra, about a dozen different snowy owls were sighted. They were always just the right distance away, perched beautifully and peacefully on slight rise – a close look with the binoculars showed the owls staring right back, tracking our movements as we were tracking theirs. If you walk little closer, the owls take off, flying low and fast over the tundra.

Bird food. Aka lemming.

Bird food. (otherwise known as lemming).

At times, off in the distance, it was also possible to see black, slow-moving shapes – unusual creatures, shaggy, and foreign to a boy from the south. These were muskoxen – chewing their way across the tundra. While in Cambridge Bay I spent some time with graduate students working on Muskox health, and I learned of the serious disease, lungworm, that is affecting these stunning mammals. Lungworm has been known from the mainland for some time, but only more recently on Victoria Island – climate change is a possible reason for this change in distribution. These nematodes use slugs or snails as intermediate hosts. Yes, there are slugs and snails in the Arctic!  Finally, it’s pretty difficult to talk about Cambridge Bay without mentioning the fish. The traditional name for this place, in Inuinnaqtun, is “good fishing place“, and that is an apt description. We ate fresh fish every day, enjoying Lake trout, Greenland cod, and the most delicious of all, Arctic Char. We were blessed with amazing weather during my week in Cambridge Bay, and our Sunday afternoon fishing trip on the ocean was picture-perfect.

Good fishing place.

Good fishing place.

Landscape and light

It’s hard to explain the North to people who have never experienced it, but let me try:

The landscape is breathtaking in its starkness.  The tundra rolls out like a grey/green/brown carpet, as far as the eye can see. It’s broken up by ponds, streams, and lakes, and broken up by slight changes in elevation. This results in a landscape that ripples with shadows and colours; a landscape that meanders, curls and curves depending on the underlying bedrock, sediment, glacial till, and permafrost. 

At first glance, the Arctic tundra appears homogenous, but after walking for hours upon hummocks and through cotton grass, you start to see the diversity of ecosystems, and the heterogeneity in microhabitats. It’s a landscape that is forever changing and providing plants and animals opportunities as well as challenges. I was in Cambridge Bay in early August, and it was evident that the summer season was ending.  In addition to the signs from the plants (lack of flowers) and wildlife (geese were moving in, in flocks; butterflies were seldom seen), the strongest evidence was the light. During the week I was in Cambridge Bay, there was about 18 hours of daylight each day, but the land is losing about 5 minutes of light each day – it’s a rapid change. Since Cambridge Bay is above the Arctic circle, it gets 24 hours light in June and early July, but by mid-August, summer is winding down. This means, however, that you can experience the most stunning sunsets – you can sit for hours and watch the sun approach the horizon from a remarkably shallow angle. The “magic” light is with you for hours. The kind of low light that makes everything slow down.  The kind of light that creates long, dancing shadows, and warms everything in a soft, gentle glow.

Arctic reflections

Reflection

To finish, I wanted to write a little bit about perspective. The Arctic makes you feel close to the earth. When standing on the tundra, the land before you contains no telephone lines, roads or apartment buildings. It’s very much like it was hundreds or thousands of years ago. You could start walking and you won’t likely see anyone else. The Arctic causes you to reflect and slow down. And most importantly, the Arctic makes you feel small. I think that’s an important feeling to have every now and then. The land is vast and old; we are small and young. Let’s remember we are here for a short while, and some of our time is probably well spent out in a forest, on a lake, or hiking the tundra.  Time on the land is time well spent, in part because it causes you to pause and reflect. I think the world would be a better place if we spent a little more time breathing in nature, and remembering what the earth is giving us and on how we ought to respect it a little more.  We owe it everything.

The Arctic makes me think of these things and for that I am grateful.

Screen Shot 2013-08-14 at 9.15.37 PM

Arctic reflections (Part 1)

So many clichés  – the Arctic is a vast, stark landscape. In summer, a land of endless days, swarms of mosquitoes and rivers teeming with Arctic char; snowy owls flying low over the tundra; Muskox roaming the lands.

The clichés are true. I’ve been north many times, and each time the effect is stronger. Each time the landscape leaves a deeper impression. Over a couple of blog posts, I want to share reflections about the Arctic from my recent field trip to Cambridge Bay (Nunavut), and try to explain why I love it so much, and why Arctic research is my passion. I’ll also share a few of my favourite photographs from the trip.

Mt Pelly

Arctic Arthropods

I often write that “Arctic biodiversity is dominated by arthropods” and I stand firmly behind that statement. Despite the latitude of Cambridge Bay (at 69 degrees North), the tundra is alive with butterflies, bees, low-flying dipterans, and spiders.  On a warm day, you can sit in the tundra and watch the careful movements of spiders as they navigate their three-dimensional world, seeking prey, or simply sunning themselves.  Over the past few years our research team has documented over 300 species of spiders living across the Arctic and sub-Arctic, and although diversity drops at high latitudes, there are still over 20 species known from the low Arctic Islands, dropping to fewer than a dozen as you approach 80 degrees North.

Arctic wolf spider (Lycosidae), genus Alopecosa

Arctic wolf spider (Lycosidae), genus Alopecosa

Under rocks in flowing water you can find black fly larvae, swaying in the current. Sometimes you find the shield-shaped pupal cases, and if lucky, you can see the emerging adults. These emerging adults are sometimes adorned with red mites. There are arthropods living within the protection of Arctic willow; careful examination of Salix reveals red ‘berries’ which are actually galls. Opening these reveals a hidden life. A secret, protected room containing the larvae of a Hymenoptera.

An Arctic Lepidoptera

An Arctic Lepidoptera (genus Boloria)

Research

A few years ago, the Federal Government announced a new Canadian High Arctic Research Station (CHARS), and it is to be built in Cambridge Bay over the next several years. This station will support and facilitate research in the North, in many different ways, from studies about effects of climate change on permafrost, to research on marine mammals. I am going to do my own research in Cambridge Bay, but with the aim of integrating research about arthropod biodiversity with other Arctic studies. I also hope to help in the development of a long-term monitoring plan, using arthropods as one of the focal taxon. Arthropods can tell us a lot about the world, and how it is changing, and long-term data are needed to ensure we have a clear sense of when ‘change’ is change that we need to pay particularly close attention to.

A malaise trap on the tundra - designed to collecting flying insects

A malaise trap on the tundra – designed to collect flying insects

I was in Cambridge Bay to start to develop these kinds of projects, and to get to know the town, community and the land.  I also wanted to collect insects and spiders in the Arctic in the late-season. I’ve worked in the Arctic a lot over the last several years, and although we have done full-season (i.e., June-August) collecting on the mainland, our laboratory does not yet have a clear idea about seasonal occurrence of different species occurring on the Arctic islands. Therefore, I was doing some collecting so that data could be gathered about arthropods on Victoria island and the end of the summer. For all these reasons, Cambridge Bay was my ‘research home’ for a week or so.

History and People.

Arctic regions of Canada have a rich history – and a history that is both tragic and awe-inspiring. Residential schools, relocation programs and stories of substance abuse, are all part of the darker side of this history. For hundreds of years, Europeans saw the Arctic as a wild land that required navigating, and a land that contained a bounty of riches, from whales to minerals. A bounty that was available for the taking. The stories are remarkable, and evidence of them remain in places like Cambridge Bay, including the influence of the Catholic church and the wreck of Amundsen’s ship, the Maud.  The search for Franklin’s lost ships continues – while I was in Cambridge Bay, a ship departed, in search of the Erebus and the Terror.

The remnants of a Catholic church, built in Cambridge Bay in the early 1950s

The remnants of a Catholic church, built in Cambridge Bay in the early 1950s

The Maud, in its resting place. The townsite of Cambridge Bay is visible in the background

The Maud, in its resting place. The townsite of Cambridge Bay is visible in the background

There has been a rebirth, however – Nunavut is a place of Inuit pride, and includes a wonderful balance between old traditions and new. The Inuit are marvellous – a people exhibiting patience, perseverance, kindness, good humour, and ingenuity. I heard stories of how runners on sleds could be made of frozen bodies of Arctic char, and the cross-braces from bones of wildlife, and frozen mosses would adorn the tops. If times were really tough, parts of the sled were edible.  Today, wood and rope is the preferred construction material!

Sled on the tundra: waiting for winter.

Sled on the tundra: waiting for winter.

Inuit culture is alive and well. I was lucky to spend time on the land with some of the locals, and I learned of edible plants, leaves that can be burned to ward of mosquitoes, and about the lice on arctic hare pelts.  The Inuit are also fabulously artistic, well known for their carvings from bones and fur.

Looking out towards the Northwest Passage.

Looking out towards the Northwest Passage.

Stay tuned for Part 2, to come next week…

Labels tell stories: natural history and ecology from dead spiders in vials

Earlier this week I was back in Ottawa at Canada’s National Spider collection with a couple of enthusiastic students from the lab. We were doing more databasing, which involves reading old labels and entering the information into a database.

Sound boring?  Nothing is further from the truth. It’s an amazing way to spend time, here’s an example:

Spiders as prey

Yes, that label for a jumping spider species provides more than a name, locality and date. It provides a story. It confirms that spiders are hosts for parasitoid wasps, and it documents an ecological interaction; one that is stamped in time and place.

Every single specimen in a museum or research collection tells a story. There are untold riches on little pieces of paper linked to biological specimens. In addition to the usual name, place, and time, label data gives us varied and fascinating ecological stories. Here’s another one:

Screen Shot 2013-06-20 at 3.13.51 PM

Yes, more evidence of one spider species preying upon another species. Intraguild predation, recorded and placed in a vial.

I love this next one – in part because you now know that bluebirds eat jumping spiders and that Arachnologists can identify the species based only on the male palp (that is all that was in the vial, it’s the little spider ‘bit’ at the bottom left). Um, I suppose the bird got the rest of the specimen!:

Screen Shot 2013-06-20 at 3.13.12 PM

Label data can tell incredible stories!  Here’s a nice set of labels that show how Phidippus jumping spiders really, really get around:

Screen Shot 2013-06-20 at 3.10.10 PM

Screen Shot 2013-06-20 at 3.11.47 PM

Screen Shot 2013-06-20 at 3.12.32 PM

Planes, automobiles, and boats.  (um, boats in Saskatchewan! A Province of relatively limited water, by Canadian standards).

Label data also provide insights into the characters of scientists. Below is an example of three different individuals all identifying the specimen as the same species. The three scientists, by the way, are preeminent Arachnologists in North America – I would trust any one of their identifications, but clearly they were not entirely sure, and all three had a look to confirm the identification. Three votes from Dondale, Maddison & Edwards, in three different decades! Yes, it’s Phidippus audax:

Screen Shot 2013-06-20 at 3.11.09 PM

Label data provide an important historical context.  I was thrilled to see this label from 1917 collected by none other than Norman Criddle (Criddle is well known to Entomologists in Canada):

Screen Shot 2013-06-20 at 3.30.40 PM

Label data provide opportunity to discuss, imagine and be inspired by biodiversity. I identified a species of jumping spider from a place called Sable Island. The species is one of the most attractive spiders in North America, Habronattus decorus

Sable Island is here:

Sable Island

So… the questions start. How did it get there? Presumably ballooning? Are these lovely critters still on Sable Island? What is the fauna of Sable Island? Is is a stable fauna? An old vial, stuck in a cabinet in Ottawa, opens to door to questions of dispersal, biogeography and biodiversity.

I think the message is clear: databasing provides a rich opportunity to paint a picture of a species, over time and over space.  

But here’s the problem: there are about 2700 vials of jumping spiders to database. Each one takes about 3 minutes to database, meaning it would take about 135 hours of work to database only 1 family of spiders, in one collection! And working in the collection is not free – paying students, travel time, lodging, etc. all take time and resources.

So far our laboratory got through about 400 specimens (15% of the Salticidae). We have barely made a dent.

This is an undeniable problem: We must capture these data and make them available for scientists to use.

How can we understand biodiversity change when most of our historical data are not yet digitized?

How can we begin to understand biodiversity patterns without knowing what is where, and when? 

When I wrote my previous post about the Canadian collection, I was pointed to Notes from Nature - an on-line resource where databasing is crowdsourced. This is a pretty neat idea – label data (and specimens) are photographed, uploaded to the site, and anyone in the world can transcribe the data.  It allows anyone with an interest in biodiversity to reach into a collection and learn the stories from the specimens.

I am hoping to try this out with spiders from Canada’s national collection. While in Ottawa, I tried taking photos of specimens, and tracked how much time it takes. It turns out it takes about 2 minutes to photograph the specimens and label. You must take out the spider, the label(s), arrange everything carefully and take photo(s). It then takes about 1 minute to edit the photo, and about 1.5 minutes for someone to enter data into a computer from a photograph instead of from the specimen itself. So, total time for databasing is 1-2 minutes longer than sitting in the collection and doing the databasing. The benefit, of course, is that there is good potential to actually get a collection databased from afar. Here’s an example of a photographed label and specimen, after editing:

Screen Shot 2013-06-20 at 3.27.57 PM

Question: would YOU help database if you could go on-line and see these kinds of images? Does it grab your attention? Even if 20-30 people agreed to database 75 or so specimens, each, the Salticidae would be done! (and, of course, someone would have to take images, and edit them beforehand).

I am keen to have your feedback…. I want to know if it’s an idea worth pursuing.

Do you want to learn stories from specimens?