The Arachnophile: hunting the wolf

Rabidosa

A wolf in the genus Rabidosa (photo by Sean McCann)

 

Hunting the wolf

 

In summer’s forest.

Armed with hand lens,

Forceps, vials, eyes and field book.

Up. Down. Under rocks, leaves, rotten logs.

Just look.

Behold! Scurry, pause, dash, dart.

Find that dark place.

All in eights: all is right.

Pedipalps and spinnerets; chelicerae and pedicel.

Chevrons? Eye shine? Perhaps a sac of treasures?

Pardosa, Trochosa, or Rabidosa?

Envisioning authors, keys, maps, habitus.

Line drawings come alive.

A marvelous wolf, hunted.

What a find! The Arachnophile’s delight!

Into the vial, destined for deep freeze.

Wait, think, imagine.

It is precious.

Not Tolkien’s monsters, or a reclusive terror.

It is Anansi, Charlotte, and Darwin’s gossamer.

Nature and natural.

History beyond our own.

Preserve? Conserve? Observe?

Catch, release, smile.

 

Agelenopsis webs

A hot, humid summer forest, with evidence of spiders.

 

 Notes:

1) The Lycosidae are impressive spiders, and go by the common name of “wolf spiders”. Here are some facts about wolf spiders.

2) This was inspired by daydreaming. Winter can be long and I’ve been thinking a lot about summer field work, and collecting arachnids in a hot, humid forest. I’ve been thinking about observing, collecting, preserving specimens. Bringing specimens back to a lab isn’t always necessarily. Sometimes watching is enough.

Frozen spiders

Winter has arrived here in the Montreal area. Brrrrrr. Last night was below -25C, there’s a bitter wind, and about a foot of snow on the ground. I found my warm mitts and down jacket, but our arthropod friends don’t have this luxury! This time of year really gets me thinking about how spiders are handling the weather….

What do spiders do in the winter?

Some spiders don’t overwinter at all, and instead die at the end of the Fall, with their hardy egg cases doing the overwintering. Many other spiders, however,  do remain active under the snow, in a little zone called the ‘subnivean zone‘ – between the snow and the ground. Others hunker down, nestled in leaf litter, under bark, or in otherwise concealed locations. On slightly warmer winter days, spiders can also become quite active on the snow surface. But all of this is generally not enough to guarantee survival, because even subnivean zones and hidey-holes can get very cold.

Maybe they freeze, and come back to life after it warms up? You may be inclined to think so – it certainly happens with a lot of insects. And, check out this photo that popped up on Twitter a week or so ago, by Nash Turley. It shows a fishing spider under a layer of thin ice, and it was still alive after Nash helped it out of its icy tomb. What the heck?

Capture

A fishing spider, under ice.

Did this spider  ‘flash freeze’, and like a good science fiction movie, pop back to life once it warmed up?

Probably not… I think ‘flash frozen’ spiders probably won’t survive. The literature generally suggests that spiders are not freeze tolerant. In other words, their tissues cannot survive the process of freezing, and ice will cause irreparable damage. Instead, I suspect Nash’s spider was already prepared or preparing for winter, and got trapped under the ice, but hadn’t yet frozen. It’s physiological adaptations involve some nifty and super-cool tricks.

Spiders are generally thought to be freeze avoidant* (e.g. here’s a paper on this), and through the process of accumulating glycols in their blood (i.e., antifreeze), are able to supercool. This means their tissues remain unfrozen at temperatures well below freezing, because they have physiologically adapted via the production of special antifreeze compounds that stops them from turning into ice. It’s a neat trick, and one that is relatively common in the invertebrate world. Of course, supercooling alone doesn’t ensure survival at extremely cold temperatures, and that’s where other adaptations come into play. Spiders will therefore find their way to the relatively insulated subnivean zone, or deep down in soil or leaf-litter. These behavioural adaptations (i.e., selecting overwintering sites), combined with supercooling superpowers, helps them get through the cold seasons. 

For me, I’ll stick to my down jacket, and enjoy how Hydro Quebec helps keep our buildings warm!
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* actually, we don’t know nearly enough about spiders and their overwintering physiology. I should state that I assume most spiders are freeze avoidant, based on the current literature on the topic – there’s a LOT more species to study, though!

A naturalist and his moquitoes

This is another in the “meet the lab” series – here’s a feature by MSc student Chris Cloutier:

I can’t remember a time when I wasn’t fascinated by the world of creepy crawly things. For as long as I have been able to grasp and crawl I have been collecting and observing insects and spiders. Although my mother wasn’t always fond of the critters I would trek through the house, my parents were very supportive of my curiosities and did their best to nurture my interests. As a family we would go camping and fishing often, introducing me to the world outside of our backyard and ultimately landing me where I am today.
My passion for studying insects began many years ago with my first entomology course in CEGEP. After completion of that program I enrolled at Macdonald campus of McGill University. Before I even started my first semester I got my first real taste of applied entomology, when Chris Buddle hired me for several months during the summer to be his field and lab technician. Let’s just say that from that point onward I was hooked.

While studying at Mac I really started to discover where my interests were in this very diverse field. I was intrigued with the ecology and natural history of insects and the amazing things that they do. I really enjoyed learning about insect-human interaction, and for some reason I was very interested in disease transmission and parasitism and the amazing enzootic pathways they can take.

Chris Cloutier: the man, the naturalist, the legend.

Chris Cloutier: the man, the naturalist, the legend.

My Master’s research began in early 2014. I had been working for several years at the Morgan Arboretum, a forested property owned by McGill, when my employer, and now co-supervisor, Dr. Jim Fyles approached me with the idea of performing some graduate research using the Arboretum as a study area. I jumped at the idea of doing this, and we got Chris Buddle on board right away. My thesis will be analysing the temporal variation of mosquito community composition across a habitat gradient which includes suburban areas, fields and various forested sites within the Morgan Arboretum. One of the reasons for this research is the fact that in many suburban and forested areas around Montreal, mosquito densities reach near intolerable levels during the summer months. This, coupled with the increasing number of cases of arbovirus (arthropod-borne viruses) infections, such as West Nile Virus, the importance of understanding where mosquitoes are located, and when, as well as which species are present is becoming more and more important.
Collection of mosquitoes takes place for 24h once a week for the entire frost free period, typically from April to November in Montreal. The traps I use to collect mosquitoes are quite specialized and are designed to capture only females which are seeking a blood meal (the ones that we worry about on our strolls through the woods!). These traps use a combination of LED light and carbon dioxide to attract the insects. The LED lights draw in mosquitoes from quite some distance, and the CO2, produced with the help of a few kilograms of dry ice, draws them ever closer to the trap. Once in range, a tiny fan sucks them into a mesh catch-bag and they are trapped.

Chris in the field, checking a trap.

Chris in the field, checking a trap.

When not out in the field, I spend most of my time with my eyes firmly attached to a microscope, sorting, identifying, and counting mosquitoes. After my first field season, I have collected just over 43,000 mosquitoes representing 9 genera and approximately 28 species. I am now faced with the task of analysing the data and making sense of all those numbers, which in fact has revealed some interesting patterns already. I’m looking forward to heading out next spring to start all over again.

The hard work.

The hard work.

I consider myself to be a “geek of all trades” with interests in everything from birding, to plants, herps and pretty much everything in between. I rarely leave home without my binoculars, and during the summer I almost always carry some vials, an aerial net and several field guides (yes, I often get some strange looks…). I’m also a husband and more recently, a father too. My wife still hates mosquitoes but I feel her coming around slowly, and my daughter doesn’t know it yet, but she will be spending an awful lot of time outdoors with us.
Follow me on twitter @C_Cloutier15 or email me at christopher.cloutier@mail.mcgill.ca if you would like to know more about what I am up to and how things are going with my research.