Weekend Expedition 54: Burns Bog and Centennial Beach


This past weekend, The Spider Crew (Sam Evans, Catherine Scott, Samantha Vibert and Gwylim Blackburn) and I set out to find an elusive and rare gnaphosid in the vast wetness of Burns Bog. Gnaphosa snohomish is supposed to be the only peatland specialist gnaphosid in Canada, and was a great reason to go out to the bog.


Believe it or not, we all piled into Daisy, a 1984 Toyota Tercel on loan from Sofi Hindmarch. Yeah, it’s got a hemi!


Samantha examines some riparian flowers on the walk in.



The Labrador Tea was fragrant and abundant.


The wild blueberries were in full swing!



I liked the way the fern was projected on this skunk cabbage.


In the bog proper, there was evidence of spiders. This belongs to a Hahniid, which Catherine will cover in an upcoming post.


A very odd construction indeed. An egg sac?


Sam managed to find a jumper on some blueberries.


and a crab as well.


Under the trees, in rotted logs, amaurobiids were common.


Interestingly, they seem to show a curious “legs up” posture when blown on. We had seen a similar reaction among Ctenids in Honduras.


An Uloborid with its amazing silk trap set.


A gorgeous linyphiid on her web. Check out her weird epigynum!



Samantha and Catherine consult the primary literature in the field. The article in question is: Bennett, R. G., S. M. Fitzpatrick & J. T. Troubridge. Redescription of the rare ground spider Gnaphosa snohomish (Araneae: Gnaphosidae), an apparent bog specialist endemic to the Puget Sound/Georgia Basin area. J. Ent. Soc. Ont. 137: 13-23.


Our hunt was turning up nothing gnaphbosid like, so we stopped for lunch.


Spidering makes for healthy appetites, especially when goat cheese, hummus tomato and basil are available.


Shortly after lunch, it was evident that the black dog of spidering failure had visited us, so we made a move for our second objective: confirmation of a population of black widows at Centennial Beach in Tsawwassen.


We were shocked at the similarities between this beach and Island View Beach. Each has a shallow bay, a large foreshore protected from high tide, abundant driftwood, sloping fields behind, and a bluff overhanging. The human traffic is a bit more intense at Centennial though.


Rolling over logs, and what did we find?


Black widows! Just look at this absolutely gorgeous overwintered male!


This guy was so spectacular… Almost the size of a young female.


Females with egg sacs and hatchlings were also around.


Here is a youngster near an egg sac.


And a large female with a new egg sac.


We ended the day back in Vancouver with some ice cream. Overall, a good effort, with 1/2 of our objectives met. We will get you next time Gnaphosa snohomish!

A wider view of Ammophila


A “normal” focal length of 27 mm (about equivalent to 43 mm on full frame, so a tiny bit on the wide side).


A focal length of 39 mm (about equivalent to 62.4 mm on full frame, so still actually a telephoto shot). Much wider than the 100 mm lens though!

One of the tasks I have set for myself this season is to start experimenting with wider closeups, a style best demonstrated by great photographers such as Piotr Naskrecki, Clay Bolt and Paul Harcourt. Shooting close and wide has the advantage of showing the subject in the context of its surroundings, and can be surprisingly effective. In fact, a vast proportion of wildlife photography contest winners are shot on wide lenses, as seeing animals in these perspectives can really make for some stunning compositions.

I have been in my 100 mm comfort zone for too long, and I feel the need to get a bit more creative with my composition. In addition, I feel like the context is missing from many of my macro shots, and going wide will help me to centre my subjects in their habitat.

While I can get wide and close with a couple compacts I have, the only SLR lens my kit capable of wide shots is the EFS 18-55 “kit lens”. It is not a bad lens at all, stabilized and light, it is easy to pack around. Last night I made good on my resolution and tried it out on some sleeping Ammophila at McDonald Beach in Richmond.


Here is the same Ammophila cluster at 18 mm, bringing in yet more of the surroundings.


Again at 18 mm, stepping back about 3 cm further from the subject. Small differences in subject distance make a dramatic effect on the picture. Also, here you can see another Ammophila cluster down below and to the right! One of the disadvantages to working with a kit lens is the hexagonal highlights in the out-of focus areas of the background. Pricier zooms have rounded aperture blades that yield a more pleasing “bokeh“.


For all of these shots, I shot handheld in aperture priority, with the subject lit with a diffused manual flash held just overhead. Mostly I dropped the exposure compensation down 2/3-1 stop to emphasize the darkening evening. This shot is at 21 mm.



And here is one shot back in my comfort zone with the 100 mm and the flash held using the Monster Macro Rig at full extension of the rail and friction arm. Be sure to check out the larger versions of all this in this flickr set.



Weekend Expedition 53: celebrating being done!


A beautiful longhorn! Stictoleptura canadensis on Tansy at Iona Beach.

This weekend, to celebrate being done with my PhD defence, I made sure to get out on both Saturday and Sunday morning. I went somewhere close by, as it has been very hot and clear here in Vancouver and the shooting gets pretty bad pretty quickly. Thus,I went to Iona and McDonald Beaches in Richmond.


One of the biggest chalcidoids: Leucospis affinis (Leucosppidae). Check out those rear legs!


A green lacewing, missing its antennae.


A nice megachilid with a cool moustache.


This sphecid is covered in dew and looking cool in the morning.


A tachinid picking up the rays of the rising sun.


A tetragnathid eating prey. It looks like this one might have a mantispid larva attached to its abdomen, something I have never seen before in Vancouver.


Things are not going well for this tetragnathid either!


A pretty Ammophila against the sky.


Skippers are out in abundance, although I have not seen them ovipositing yet.


This and the next photo show the dramatic effect of the background light using the Monster Macro Rig.


The background is at a sweet spot to blur at f13.


And of course, with any morning walk on the beach, I found some Coelioxys!


A cluster of Ammophila against the sky.


A tiger moth carcass being stripped by Tetramorium ants (Pavement Ants). I have been seeing more and more of these!


Defending my PhD thesis


Thursday morning last week was a pretty special day; it was the day I defended my PhD thesis. For those of you who don’t know, a thesis defence is a formal examination, wherein the candidate (me) gives a public seminar on their thesis, and then is questioned by an examining committee, generally composed of their supervisory committee, plus an internal and external examiner, and all headed by a chairperson selected by the department.


Here is the room I defended in. We figure it had 45-50 people in total.


Catherine made some great caracara cookies to go with the coffee and water (which is required at defences!).

My examining committee was headed by Dr. Margo Moore, who did a great job keeping the event rolling and the atmosphere relaxed. Dr. David Lank was my internal examiner, a great guy I have always gone to with questions on bird research (we do not have a lot of institutional experience to draw on in a chemical ecology lab). My external examiner was Dr. Keith Bildstein, a researcher at Hawk Mountain Sanctuary, with decades of experience in raptor research and in particular experience studying Striated Caracaras in the Falkland Islands and Patagonia.  My advisory committee consisted of Dr. Sean O’Donnell, who was absent for the defence, but there in spirit (he is doing fieldwork in Costa Rica), Dr. Ron Ydenberg, an expert in bird foraging behaviour, and of course my supervisor Dr. Gerhard Gries.

I gave my 40 minute presentation, outlining my research on Red-throated Caracaras, focusing on several aspects of their biology:


It is not clear that Red-throated caracaras build nests, as our observations in 2008 and 2009 showed that they nest in cleared areas of large epiphytic bromeliads. They seem to have only a single chick per nesting, and have some of the most extreme cooperative breeding in the bird world, with up to 6 or 7 adults providing care to a single chick.


They are specialist predators on social wasps, and probably are responsible for a lot of brood mortality in these animals. They prey on a wide range of genera, mainly swarm-founders and almost invariably aerial nesters.


They are extremely social, vocal and territorial, with a repertoire of calls and displays, and even use physical conflict in territorial disputes.


Contrary to previous hypotheses, we found no evidence of a chemical wasp repellent, but discovered that the caracaras exploit the absconding response of their swarm-founding prey to avoid harm when attacking wasp nests.


The work in my thesis was not done single-handedly. I had great help from field assistants, granting agencies and the CNRS is Guyane. Here is Onour Moeri, my assistant in 2008 and 2011 with a Red-throated Caracara we had radio-tracked.


This is Tanya Jones, a biology graduate who is now a triathlon coach, who came to French Guiana with me in 2009 and 2010.


Catherine Scott, also known as @cataranea, came in 2012 for help with the army ant portion of the thesis (soon to be published!).



Patrick Chatelet, of CNRS Guyane was our good friend and host for much of our fieldwork. He has been at the Nouragues station for longer than most of the monkeys.

Picture 115

Philippe Gaucher of CNRS Guyane, is a great guy to have on your side when doing raptor or frog research in the rainforest. Here he is climbing the 2008 nest tree for the first-ever glimpse into a Red-throated Caracara’s nest.


My mom attended the defence, and it was great having her there. She has encouraged me through all the years of this process!


A bird in the hand: at the end of the seminar, I was questioned for about 1.5 h. Most of the questioning was more in the form of a discussion and I found I had quite a bit to say to everything thrown at me. In the end, the decision of the committee was to accept the thesis with minor revisions. When that is complete, I will have fulfilled all the requirements for the PhD program, and the school will award my degree.

After the defence, we had lunch with teh committee, and then went to Trout Lake for a bit of a celebration. Here are some shots from the defence and the after-party. I know I have missed some important faces (Gerhard and Regine and Keith Bildstein!), but I hope you will forgive me, as I was just feeling relief!

This slideshow requires JavaScript.











Back to the beach!


Catherine and I had to make a quick run back to Iona Beach last night to retrieve a fallen Raynox DCR-250 and to search out some Micropezid flies for Morgan Jackson. It was a quick trip, but we succeeded on both counts! Of course, I also took the opportunity to do some shooting as well. Here is what we got.


A Tibellus (Philodromidae) feasts on a damslefly.


A damselfly feasts on a chironomid midge.

IMG_3028 IMG_3049 IMG_3056 IMG_3064 IMG_3082 IMG_3094 IMG_3096