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My favourite photos from Guyana

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Sometimes, a lucky circumstance presents itself, and you are ready to seize the opportunity. I got many wonderful photos on my trip up the Rewa River in Guyana this spring, but ironically enough, my favourite set of shots came within the first hour on the boat!

We spotted this hawk on the left bank of the river, and we quietly motored over to it. This was a Roadside Hawk (Rupornis magnirostris), a small, primarily insectivorous hawk found from Mexico to northern Argentina. It has quite a boring name, but it is actually quite lovely and unusual, with a body form akin to an accipiter rather than its Buteo cousins.

Anyway, these were some of the loveliest bird pics I got on the whole trip, so please enjoy them!

The hawk was very obliging as a model, turning this way and that, and looking at us with curiosity.

This view shows how close in body form they come to an accipiter. Short wings, long tail, fine barring on the breast, broad bars on the tail.

In fact, other birds are convergent in form to accipiters, notably in America the forest falcons.

Such a lovely hawk! For larger versions of these images, click here.

Guyana: a myrmicine trapjaw ant

Jun8

Sometimes, I never really know just how special the subjects I photograph really are. During the second night we spent on the Rewa river, I was dealing with blistered, sunburned hands as well as moderate fatigue. After dinner, it was tempting to crawl into my hammock and snooze, but I forced myself to go out, at least for a bit, and try for some nighttime arthropods.

A leafcutter trail briefly caught my attention, but doing any elaborate setup for shooting was beyond me that evening.

Right in our camp, just a few metres from the cooking tarp, I found these amazing ants. At first I thought they were leafcutters, but when I got closer I realized that this was some kind of myrmicine version of a trap-jaw ant! I had never seen these in French Guiana, and in fact did not know of their existence. These were Daceton armigerum, one of only two species in the genus, related to the leafcutters, but tree-dwelling and predaceous. They have evolved these amazing, lightning-fast mandibles, like their ponerine equivalents, which they use for seizing prey. Their extremely crazy-shaped heads contain the heavy musculature needed for this strategy, and a trigger mechanism to release all of the force built up in a single stroke. For a great paper on this, showing the internal morphology, click here.

Unlike the ponerine trap jaw ants, they are quite fast and active, with seemingly large colonies contained in hollow trees.

Adult-adult trophallaxis is a difficult affair with these massive jaws, and the ants seem to use their maxillae for this.

I can’t get over these amazing heads!

A few of the ants walking towards nest entrances had prey, such as this pretty but unfortunate beetle.

Social life: most ants that passed each other on foraging trails up the tree at least antennated each other. It seems that other than tiny Crematogaster, no other ants are tolerated on this tree.

A few workers were carrying males, but whether these were alive or dead was hard to tell.

The males looked very different from the workers, as with most myrmicines, but really not that different from a lot of other mymicine males.

Nest entrances seemed to be scattered around the trunk, and these workers looking out show that there are definite castes in this species.

Some nest entrances were busier than others! Here are some males poking out along with a range of various-sized workers.

With a bit of waiting, the males came further out.

Daceton armigerum was certainly one of the oddest ants I had ever seen. If I had known how unusual it is to photograph them in situ, I probably would have devoted more time to photographing them.

The lesson is, even if something is big, obvious and odd, if it is from the rainforest, it may not have received much attention!

Gronenberg, Wulfila. “The trap-jaw mechanism in the dacetine ants Daceton armigerum and Strumigenys sp.” The Journal of experimental biology 199.9 (1996): 2021-2033.

Moffett, Mark W., and John E. Tobin. “Physical castes in ant workers: a problem for Daceton armigerum and other ants.” Psyche: A Journal of Entomology 98.4 (1991): 283-292.

Guyana: the other archosaurs

May23

On my trip to Guyana, I was not only on the lookout for birds, but also their relatives, the crocodilians. Guyana is home to 4 species of caiman, including the largest and smallest species in the world.

On the Rupununi and the lower Rewa, I was amazed at how many black caiman there were. Paleosuchus niger is the largest caiman, and in my mind I still thought of them as very rare. Conservation efforts and a reduction of hunting have caused a definite improvement for this beautiful species across their range.

These large caiman can be dangerous, so while in their territory we made sure to bathe in shallow water where we could see them coming. With predators such as this, you are probably safe if you do not enter a good ambush zone, such as a place with a steep dropoff.

Rambo holds a baby black caiman, which we found in an aggregation near our camp one night. In Rambo’s hometown, Yupukari, there is a conservation and research outfit called Caiman House where the locals participate in monitoring and study of black caiman. Rambo has experience capturing, tracking and nest monitoring these impressive animals.

Jonathan posing with a beautiful little caiman. The babies tend to stick to protected “nursery” areas, as they are easy prey for birds and large fish.

If you want a juvenile caiman to open its jaws, a little tickle on both sides of the base of the lower mandible will produce this posture.

Above the major rapids, the Rewa is devoid of black caiman, and instead spectacled caiman and dwarf caiman abound. Here is a Schneider’s dwarf caiman cruising by our camp. I had seen Cuvier’s dwarf caiman in French Guiana (small ones living in small fast creeks), but seeing the adult Schneider’s was a revelation. These guys get fairly large, and inhabit even slow-moving sections of the river.

Brian tossed a piranha piece at this dwarf caiman, and it seemed to know exactly what was going on. It has probably seen several fishing groups upriver and has learned that when a boat pulls in, fish pieces from cleaning are often tossed out. This one had some fishing line attached, so we could try to haul the beast into shallower water. By the time the caiman got it’s feet planted, any further movement of the caiman was impossible!

All of the crocodilians we met were quite shy, and even large black caiman would flee if we caught them in shallow water. This dwarf caiman was willing to come for tossed fish, but not if we were too close to the water’s edge.

Some of the bolder caiman would stay on the bank as our boat passed, but most of them would flee for deep water.

If you go out in the woods in the tropics, be sure to look out for the local crocodilians! They are fascinating and beautiful animals.

Guyana Riverside Birds

May17

A juvenile Great Black Hawk, Buteogallus urubutinga. These large buteos are probably the most visible raptor along the rivers, although they are often quiet. In French Guiana, they are called “Buse Urubu”, or “vulture hawk”.

Travelling by boat offers many advantages over walking, not only in saved energy and efficiency, but also in that approaching wildlife is often much easier. I have covered many of the fish-eaters we saw along the riverside before, but here are some other species that we saw quite often along the Rewa.

Here the Great Black Hawk appears in adult garb. The long bare legs are well-suited to their habit of foarging on the muddy shoreline. They prey on frogs, lizards and snakes, as well as fish occasionally. I actually did a camera trap study a few years back at a great Black Hawk nest, but the data are pretty sparse due to death of the nestling after a few days.

Another Great Black Hawk juvenile looks ready for action, but probably isn’t. Mostly they sit and call for food from their parents!

A Muscovy Duck in flight. These treehole-nesting ducks are the progenitors of the domestic strain, and are large and impressive birds. They seemed to travel long distances along the river, and spend the night on quiet ponds and branches of the river. None allowed close approach.

Red and Green Macaws (Ara chloroptera) nuzzling on a tree. These macaws, along with two other species, were loud and obvious along the river. They also travel large distances, and sometimes engage in playful mock combat on high branches.

The Blue and Yellow Macaw (Ara ararauna) was also quite abundant. They are a bit larger and deeper-voiced, but sometimes seem social with the other species.

The Swallow-tailed Kite is an amazingly beautiful raptor, which also occurs in Florida. Guyana has both migrants and resident birds.

Black Skimmers, also quite cosmopolitan, breed along the river. We often saw them in company with Large-billed Terns.

The Large-billed Tern (Phaetusa simplex) could be found nesting on sandbars. Sometimes they would dive-bomb our boat.

Three species of swallow were super abundant. We saw White-winged Swallows and White-banded Swallows most commonly, but also Barn Swallows high up on the Rewa.

Dead wood in the river was the favorite perch of most of the swallows. In the evenings, swallows would be replaced by bats and swifts, and sometimes all three taxa would fly together. .

We also saw a lot of nightjars perched on the river, in their usual cryptic fashion.

Here is a Blackish Nightjar, recently disturbed from her nest.

And here is her offspring! Can you see it?

A closer view.

A Green Ibis. These ibises were always a bit disturbed at our approach, and would scramble noisily into the forest.

Rambo checks out some tanagers high in a tree. We didn’t often see smaller species along the river, and in fact I found sedentary camp life in French Guiana was better for seeing these types of birds. What an awesome job it must be to guide people upriver in such an awesome place. If I had the means to do so, I think this is something I might like to do one day.

A journey to meet the Red-throated Caracara in Guyana

Apr16

Recently, I made a long journey in South America, up the Rewa River in Guyana, in search of caracaras and other Amazonian fauna.

The story of this trip takes a bit of explaining. Last year, after our abortive research mission to Honduras, Catherine and I were holed up at my mom’s in Victoria writing our respective theses. We had little occasion to go to Vancouver, but in April we both needed to go over to take care of some administrative details at the university. While sitting in the lab after managing our red tape, the phone rang. As usual, no one in the lab jumped up to get the phone, so I picked it up and found that the person on the other line was looking for me, and wondering if I wanted to talk about caracaras.

Jonathan Meiburg, looking at home far up the Rewa, in the heart of the Amazonian forest region.

Well, after a good 90 minute conversation about my favourite loud birds and their relatives, I found out that the fellow I was speaking to was Jonathan Meiburg, a professional musician and a student of the biology and biogeography of striated caracaras (the fabled “Johnny Rook” of the Falkland Islands). I found out that Jonathan was a great student of caracara biology, and had written a wonderful thesis on the Johnny Rook (which he should really put online…I am not kidding, it is an absolute pleasure to read!) which also covered the biology and paleontology of the other caracaras.

We continued to keep in touch from that time, until last fall when Jonathan invited me to accompany him on a journey to the Amazonian forest to meet the Red-throated Caracaras, which he and I agree are the oddest of a very odd group of birds. The plan was to go to the Republic of Guyana, where Jonathan had some acquaintances working, and to journey up the Rewa River to the heart of Ibycter territory: the primary rainforests of the Amazonian bioregion.

In the following posts covering the trip, I will not stick to a travelogue format, but rather will skip around, introducing the characters (human and otherwise) we met along the way. As I write this, Jonathan is still out there in the forests of Guyana, hunting for the elusive heart of Amazonia, no doubt being serenaded by the harsh screams of the Red-throated Caracaras.

A very spidrous summer planned

May4

So this is where I find myself: I am currently employed as a field assistant to my partner Catherine Scott, as she spends the spring and summer of 2016 doing thesis research on Vancouver Island. Over the winter and early spring, I had several interviews for postdoc positions, but ultimately did not get any offers. I am still in the market, as this field gig is not paying much, but this is where my employment situation stands.

Dang, that’s a long trip!

The fieldwork may not pay much, but it sure has been exciting. The first stage of the work involved a ridiculously long roadtrip from Toronto to Texas, and out to LA, up the coast and across the Strait of Juan de Fuca to Victoria. Our objective in this was threefold: 1) we had to collect some beautiful “Texas widows”, a variety of western black widow (Latrodectus hesperus) for later lab research, and 2) we had to attend a wedding in Los Angeles and 3) we needed to get our vehicle to BC for the fieldwork.

Of course, this roadtrip was a great opportunity to get some cool shots of the natural world along the way. In the following shots, you will get a taste of what we encountered.

Catherine taking notes on spiders we collected.

Joseph Lapp, an arachnologist in Austin graciously took us out for some spidering and lunch near the UT Austin field station. We met up with many great people along the way, including Bekka Brodie and Viorel Popescu in Athens OH (former labmates), Alex Wild in Austin, Terry McGlynn in Pasadena, Christy Pitto in southern Oregon, and Thomas Shahan and Kathleen Neeley in northern Oregon, who spent the day with us shooting photos and wandering the canyons. I apologize for not taking more people pictures!

Catherine collects a Texas widow in the boonies of southern Texas.

Here is what the Texas widows look like: the adult females retain the juvenile colour pattern, with flamboyant reds and yellows on the dorsal surface of the abdomen. The extent of this red varies, but this is pretty typical.

Southern Texas is awesome for birds. We saw a great many Crested Caracaras, which was a big highlight of the trip. I last saw these birds in Guyana.

We got to see 3 species of recluse spider. This one is the Big Bend recluse, found about 100 km east of the Pecos River valley.

Another highlight was finding Scytodes spitting spiders. We saw both Scytodes thoracica as well as this unknown (to us) species from southern Texas.

In the Seminole Canyon, we found the only Aphonopelma tarantula we saw on the trip.

It was extremely frustrating to have to burn through Arizona and New Mexico to get to the wedding, as there is absolutely stunning mountains and countryside to explore. Here we are passing by a wonderful region…

After the wedding in LA, we got some opportunity to change the oil, hang out with Terry McGlynn and see some hawks at Palos Verdes.

In Laguna Seca, near Monterey CA

The beautiful Diaea livens, a green crab spider found on oaks in California.

In Monterey, we met up with the invasive Badumna longinqua, a desid spider that makes messy cribellate capture webs very close to the ocean.

While searching for Badumna near the docks in Monterey, we came upon this sea lion chilling out. They are really quite tame in the harbours!

The $500 spidermobile passes north through the Golden Gate

Out for the day with Christy Pitto, at the headwaters of the Rogue River in southern Oregon, we found this beautiful Tibellus, and I found a new angle to shoot it from.

Our coolest spider find was with Christy Pitto, a gorgeous Mecicobothriid from near her cabin.

Catherine spidering with awesome macrophotographer Thomas Shahan in Salem, OR

Catherine giving an impromptu spider lecture to Thomas Shahan and Kathleen Neeley. The $500 spidermobile is in the background.

We embark on the MV Coho from Port Angeles to Victoria

Catherine in the field at Island View Beach. We are working on the lands of the Tsawout First Nation, who have a large reserve near Sidney on the Saanich Peninsula.

initial mapping points for female western black widows we will monitor and observe over the next several months.

This is what we will be watching this summer: a male black widow courting on the web of a female at Island View Beach

We will shift to a largely nocturnal schedule to match the widows. Here Catherine observes courtship on the beach.

Drifting on the Rewa

Nov28

To get back to my posting on the trip to Guyana I made this spring, I should get some of the most charismatic megafauna out of the way.

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OK! Are you still with me? Let’s talk about drifting on the Rewa! When we reached our highest-upstream camp on the Rewa, Josey, Brian and Rambo took Jonathan and I out “drifting” several times, basically motoring upstream a few kilcks and then drifting and paddling the boat downstream, in the hopes of seeing wildlife that would otherwise be scared by the motor. We did this several times, most often in the evening to get views of all the animals that come to the river to bathe or drink.

Using the drifting technique, we were able to see several family groups a capybaras, a species I had not previously seen in daylight!

The boat was not as quiet as a canoe, but after days of motoring on the river, this was pretty nice!

The capybaras were often accompanied by large horseflies. Surprisingly, none of these flew over to us, even when their hosts slipped into the river.

The capybaras take to the river when disturbed, and can even navigate extremely fast currents. I remember many times at Parare in French Guiana being startled by big capybaras splashing into the fast-flowing Arataye. This stretch of river was much more sedate, so allowed us to see the animals swimming quite well.

As usual, some of teh capybaras has things perched on them. This is a giant cowbird, which feeds on ectoparasites on the large rodent. Even Black Caracaras do this, but we did not see one doing so.

Drifting quietly also allowed us to spy wildlife we might have missed from going to fast: this iguana was well-concealed at most angles.

We also saw a number of tapirs, which often come to water to bathe in the morning an evening. These are the largest of the South American ungulates, and are very impressive see!

The tapir is a very shy creature in the wild, probably because they are hunted by anybody who can kill them! Unlike capybaras, which breed rapidly, tapir are one of the many species that quickly drop in population with even moderate hunting.

Here was a female tapir we saw at noon, not drifting. I did not get a shot of it, but she had big wounds in her flank, likely from a jaguar or puma. Rather than a relaxing bath, this poor tapir was likely hiding from a predator in the water.

This is what a tapir looks like shaking off!

They look much more elegant when their snout isn’t flapping madly!

Gorgeous animals! We felt really lucky to be able to see so many of these shy and magnificent creatures!

Cheapskate Tuesday 27: the Yongnuo 35 mm F2

Jun30

So my soujourn in Guyana was not entirely without casualties. Although I avoided getting eaten by the jaguar, my Canon 50 mm 1.8 II died. I have no idea what happened, but the whole front assembly became detached from the rest of the lens. Everything still works, aperture, focus motor, but I cannot figure out how to snap it back together.

The carnage: maybe the jaguar attacked it!

Anyway, I needed a new fast prime, and it just so happened that when got back from the jungle, the YN 35 mm f2 was announced. It was retailing for 110 bucks, the same for the 50, and since i have a crop-frame camera, a 35 sounded like a nice focal length for a fast lens. After all, the legacy of the fast 50 mm prime is a holdover from film days, where it would be a “normal” lens on a 35 mm frame. With my 1.6X crop frame Canon, 35 mm is just about a normal focal length, so what I am really getting is not a wide lens, but a fast normal lens. I ordered one!

The waiting for shipment took way longer than expected, as it was on the slow boat from China, but when it arrived last week, I immediately tried it out. The first few images I took with it were OK, but not stellar. Then I remembered to take the protective plastic off the rear element!!!

OK, this lens is pretty cool, it is nice, fast focusing and decently well built (seems on par with the el cheapo Canon 50 anyhow, and is quite reminiscent). It does have a metal mount, and the autofocus switch feels way nicer than that of the Canon. So far so good. What about the images?

I intend to use this for a number of things I used to use my 50 for: documenting social events, fieldwork, and sometime putting it on tubes for macro. Here are my results so far:

Social documentation

Nice and sharp details, and the real advantage of this lens for me is that I do not have to run backwards to frame up a shot. It sees what I see!

I like the way colours are rendered (although a better body would help with the greens!)

The lens is decently fast in focus response, and hence feels fun to use.

The lens is not so wide as to significantly distort faces in close-up shots.

Most importantly, it captures the expressions of huskies well, especially that moment they discover there is a bag of chicken skewers nearby.

Because the lens is bright, getting focus right in the dark is way easier than using a slow zoom.

Field Documentation

Again, I like the focal length. If I want a snapshot of a GPS and a pitfall trap, it works great.

For documentation of habitat, it is wide enough to show the scene.

It can even work for a bit wider view of larger insect phenomena!

Macro

It does focus pretty close for a wide lens, but the magnification sort of sucks for macro.

With a Raynox DCR 250, it can be used for closeups, even in natural light. It gets to about 1:2. With 31 mm of extension tubes, it gets a bit better than 1:1. With more extension, the working distance gets pretty darn short. i will experiment with this kind of thing, but for anything approaching 2:1, I would be better off with the 100 mm as a starting point.

“Native” magnification. Not too impressive.

With 31 mm of tubes. A usable macro setup, though subject distance is small.

The seven bladed aperture definitely renders out of focus highlights better than the Canon 50 mm 1.8 II.

Verdict

Well, this is certainly a usable and enjoyable replacement for my 50 1.8. In fact, with its focal length, it will likely be way more useful to me. I am impressed with the decently close focus, the fact that it is fast and light, and that it fits my budget! One thing to keep in mind about this versus the Canon 50 is that the front element is much less recessed, and hence ghosts and flare may be more common. I did not notice anything other than small blue ghosts when the sun was right in the frame.
I would say if you can afford to, one of the Canon versions of this lens would undoubtedly hold value way better, and perhaps offer an edge in build quality or some aspect of performance. But this is definitely a usable lens, and is quite sharp even wide open (I will post some samples soon!). I will certainly be making a lot more use of this lens than my 50 got, as this is a more valuable focal length for documentation and snapshooting. Look forward to seeing more from this lens in the future!

Accumulation: excess photos from the past few weeks

May27

Myrmica rubra tending aphids, Annacis Island.

I am working again with ants this summer, and have been getting out a bit for work and on the weekends for special outings. I have been accumulating a number of excess photos over the past few weeks that don’t really fit in with the special topics (Guyana, Expeditions, Okanagan) so I have put them together here. I hope you enjoy them!

Myrmica specioides ascends a blade of grass.

Carabus nemoralis in the hand…Worth two in the bush!

Formica oreas workers cutting some grass for their roof. These are “thatching ants” and the top of their nest is insulated with cut grass. Annacis Island

I see you, sac spider! South Burnaby.

A tetragnathid on a flower. Iona Beach, Richmond.

Myrmica incompleta, moving larvae to safety. Iona Beach, Richmond.

A damselfly, still sleepy in the early morning. Iona Beach.

Trying for a bit more detail with the Raynox DCR 250.

Phidippus johnsoni. Iona Beach.

A wolf spider with a great egg sac. Iona Beach.

A gorgeous Sialis alderfly, Chilliwack.

The Ammophila are out again! McDonald Beach, Richmond BC.

And speaking of sleeping Hymenoptera, here is my first Coelioxys of the year! Iona Beach, Richmond.

With fingertip for scale.

A gorgeous sawfly from Maplewood Flats, North Vancouver.

You can get some really diffuse, wrappy light with just a handheld reflector!

A big, likely gravid Dysdera. Iona Beach.

Speaking of Dysdera, Catherine and I had some dysderalings! (Well, one of our captive females did).

Local badass cat! Super friendly though! Vancouver.

Here is an amazing mite, probably an undescribed species of Lasioerythaeus! McDonald Beach, Richmond BC.

Going on Vacation!!!!

Apr24

So Catherine and I have a week off this coming week, so we are planning to go for a bit of a vacation in the Okanagan. We will be mostly in the boonies, camping and searching for critters, so will be out of contact for a bit. It also means I will have to interrupt my series on the Guyana trip. When I come back it will be all Guyana, all Okanagan, all the time!

Our transport will be a venerable old Honda Civic that Catherine picked up for 500 bucks! It has new brakes and everything so should be a safe and reliable steed to carry us eastwards.

We are going to look for a long list of interesting animals, from scorpions and rattlesnakes to a few special spiders (Argiope, Antrodiaetus, Latrodectus [of course!)). Catherine and I will be trying to get some shots of rubber boas as well. Who knows what we will see! This will be a time for us to get out and get busy searching for whatever we can find. I think it will be awesome.