A Thanksgiving meal, right out of the field

We are so excited to welcome Jennifer MacMillan back to the blog today. Earlier in 2015, Jennifer told us about her time spent on exchange in New Zealand. Now she is back, and this time tells us a rather appropriately-timed story about enjoying a Thanksgiving meal, right from the field. Happy Thanksgiving to Jennifer, and all of our American readers/posters! We are so thankful for all of you. For more about Jennifer, see the end of this post. 

Thanksgiving is my favourite holiday. Everything about it is awesome: the food, the family, the fun times. But the main reason I love this day is because I get to celebrate it twice a year.

I have dual Canadian and United States citizenship. Along with other perks, this means I have the pleasure of over-eating on the second Monday in October and the fourth Thursday in November every year.

Since graduating from a Canadian university, I have been working in the States. I am currently in Alaska working for the Division of Agriculture as a Field Technician at the Plant Materials Center (PMC). The main focus of the PMC is the production of native plants and traditional crops. I spend my days on a 400 acre farm where I maintain greenhouses and fields while assisting with the Horticulture Program’s Observation Variety Trials. We evaluate cauliflower, broccoli, apples, asparagus, and potatoes to see how well they hold up in the Alaskan climate.

Our Potato Greenhouse getting started.

Our Potato Greenhouse getting started.

 A bucket of Romanesco that was measured for Broccoli Trials.

A bucket of Romanesco that was measured for Broccoli Trials.

Conveniently, harvest came just in time for Canadian Thanksgiving. Lucky for me, I helped plant pretty much every side dish you can imagine and was definitely excited to collect my reward. Also, the PMC has a staff full of avid hunters so between moose, caribou, and sandhill cranes, there were more than enough meat options on the table. I even helped add fish to the menu!

Small Halibut are called “Chickens”, a perfect substitute for turkey.

Small Halibut are called “Chickens”, a perfect substitute for turkey.

Regardless of where I am for the holidays, I am lucky that I always have a diverse group of interesting and entertaining people around to break bread with on Thanksgiving. No matter which month we celebrate.

Small Halibut are called “Chickens”, a perfect substitute for turkey.

Jennifer is currently working  for the Division of Agriculture as a Field Technician at the Plant Materials Center in Alaska. Jennifer completed her BScH at Queen’s University in Kingston, ON, Canada, studying masting in sugar maple trees. She is an avid cyclist and nature-lover.

Studying guppies in Trinidad

For National Fishing Week, Dispatches from the Field welcomes Tim Hain, a biologist at the University of Western Ontario to tell us about his fieldwork studying the not-so-fancy-looking (but very cool for evolutionary studies) guppies in Trinidad. To find out more about Tim and his fieldwork stores, check out the end of this blog for a link to a book he recently published!

Many North Americans have heard of guppies – perhaps because they or a friend had guppies as pets, perhaps because they have watched Bubble Guppies on television. Aquarium hobbyists have an enthusiasm for guppies because these fish have natural variation in colouration and fin size or shape that breeders have exploited to develop many different beautiful strains with descriptive names like tuxedo, sunrise, mosaic, snakeskin, or swordtail. Although “guppies” have name recognition with the public, many people do not realize that these little fish are a favourite among researchers in evolutionary ecology. In fact, guppies are one of the best vertebrate species for studying evolution in the wild, particularly on the island of Trinidad in the West Indies. Because guppies have short generation times and waterfall barriers that restrict migration, there is variation in behaviour, life history, physiology, and appearance among populations that can often be attributed to variation in the local predator community.

Image 1

Image 2The classic story is that guppies below waterfalls are subjected to predation by large vision-oriented predators, so male guppies in these populations tend to be cryptic in colour to avoid being eaten.Image 3

 

 

 

 

Above waterfalls, the predators are either smaller and cannot eat adult guppies Image 4or eat using tactile or chemical signals,Image 5

so male guppies from these populations are free to evolve conspicuous bright colours to attract females.Image 6Many evolution students will have heard all about this. But “science-world famous” is very different from “world famous.”

 

 

In fact, most people do not know how important these insignificant-looking fish are. When I first went to Trinidad in 2006 as a Ph.D. student, I had been studying guppies for three years. At its most fanciful, my imagination pictured monuments to guppies at important sites around the country.

Of course, I did not truly expect to find statues of guppies, but I was amazed by how common guppies were in the country. My first ‘wild’ guppy sighting was in a sewer along the major east-west road, and this was not unusual.Image 7 In fact, they are so common that many locals were surprised that someone would travel from Canada to study them. In some locations where I collected guppies, I would attract a small crowd. Because I neither looked or sounded like I was from around there, local people would ask me what I was doing. One middle-aged Trinidadian that I spoke to was confused when I mentioned guppies, but when I described them, he said “Oh, you mean canalfish.” In Trinidad, guppies have this common name because they are frequently found in sewers and ditches alongside roads. Several times I used this name with Trinidadians to refer to guppies, and they knew what I meant.

Because female guppies give birth to live young, a single pregnant female can establish a population. This makes guppies master colonizers, and I saw them in a huge range of environments. Image 8The best-studied guppies are native to the Northern Range of forested mountains, where waterfalls break up narrow streams, but they are also founder in wider, dirtier rivers and some unique geographical features, like Pitch Lake in the southern part of the country.

Image 9a

My mother and a guide.

Pitch Lake was formed when pitch – a resin once used for waterproofing ships – bubbled out of the ground and now covers 40 hectares of area . It resembles a naturally-formed parking lot, but without lines and full of fissures that give the tarmac area structure. Rain filled these fissures, and guppies have found their way to the lake and become established. The unusual water chemistry of Pitch Lake and the black substrate (leading to high water temperatures) means that it is very difficult to rear these guppies in the lab.

One environment where I did not find guppies was in the brackish estuaries along the northern coast. Guppies can tolerate light saline environments, but in one tea-coloured estuary that I visited, I instead found the congenic Poecilia picta fish. Image 10The low visibility in the water of that river might explain two unusual observations I made: low colouration of P. picta males, and transparent bodies of their predator, a prawn.
Image 11

 

Transparent bodies are also found in deep-sea fish, which live in low-light (or no-light) environments: an interesting example of convergent evolution.

Perhaps the reason why guppies are such an appealing textbook example of evolution is in how intuitive and simple the explanation is: the same geographical barriers that restrict predator presence also restrict gene flow, and predation as a selection pressure drives trait differentiation. Guppy researchers know that the story is a little more complex than that, but these wrinkles in the story seldom make it into textbooks. So, I was left to independently discover these things for myself.

One variation on the story is that waterfalls are not the only feature that restrict large predators. For example, I found one ‘low predation’ environment located between two ‘high predation’ environments because the water in one stretch of the river was too shallow for the larger predators to enter. Male guppies in this stretch were more colourful than males I found upstream.Image 13Image 12

A second under-discussed variation on the story is the presence of avian predators. I often saw striated herons or little egrets walking alongside narrow streams, looking for guppies to eat. I also saw or heard kingfishers around my collection sites. Image 14These birds were skittish and difficult to photograph in the act of feeding, but their intention was clear. What is less clear is if they exert a selection pressures on guppies to be more cryptic in colour, or if their feeding habits are random with respect to colour. I do think that avian predators are important to guppy evolution – I suspect that guppies colonize new environments by escaping these flying predators after being given a short trip.

My fieldwork in Trinidad taught me many things about guppy evolution that I could not have learned from a textbook. Who knew that such small and common fish could be so interesting?!

Tim Hain is a biologist at the University of Western Ontario in London. He completed his PhD on kin recognition and multiple mating in guppies and bluegill sunfish, and he did his fieldwork in Trinidad and at the Queen’s University Biological Station. His first trip to Trinidad was for eight months, and he recently published his memoirs (Fieldwork: Stories from Trinidad) of his time living in the country on Amazon. Tim currently teaches at UWO. You can follow him on Twitter (@tjahain).

The unpredictability of working with wild animals

Even though I am mostly in the lab these days, somehow I am still subject to the unpredictability of working with wild animals. The research project I am currently working on uses yellow perch eggs collected within under 24 hours after fertilization. I was lucky to find a fish farm in central Ontario that had “wild” yellow perch. I say “wild” because although they live on this fish farm, they still live in a fairly natural habitat. Achieving the right timing of egg development was the tricky part. I had to wait until I heard that the adult yellow perch were spawning and drive up there to collect the eggs within a day. Essentially I was like a doctor on call waiting for a delivery (of yellow perch eggs).

ponds at the fish farm

Natural ponds at the fish farm are a great habitat for yellow perch.

I originally spoke with the owner at the end of February and he said he would give us some perch eggs. However, he was reluctant to give up much detail about the fish. When I asked when they usually spawn, he replied, “I can’t tell you when those little buggers are going to spawn; I’m not God”. Yellow perch in this area typically do not spawn until mid April so I was not surprised, given the cold February we had, that they would not be near ready.

At the end of March, I received a phone call from the owner who explained that he had caught two females that were “as big as footballs” and that they could spawn any day now. (Side note – I think it is very interesting how people describe their study species. For example, the seabirds I was studying for my master’s thesis were often described as “flying tennis balls with wings”.) I was not ready for the fish to be ready; I thought I had two more weeks to prepare for the experiment! I scrambled to get all of the equipment together so that at any point I was ready to go collect the eggs.

Big tanks in front of the ponds.

From eggs to fry: the yellow perch are collected and kept in big tanks until they are old enough to be put back into the ponds.

And then I waited. The owner told me not to call him for updates as it would take a lot of his time. But no sign of eggs. So I waited longer. Still no eggs. At this point, it was now the end of April and I started to get worried. Did the owner forget to call me? Did he lose my number? Would the perch ever lay their eggs? Was the project ruined!? (Questions in field biologists’ heads often escalate quickly).

The owner finally called me last week and told me that the yellow perch had spawned and there were a few strands of eggs that I could collect.

Using a net to scoop the strands of Yellow perch eggs out of the pond.

Scooping eggs out of the pond. Don’t fall in!

The next day I drove a total of 6 hours to retrieve the eggs and bring them back to our lab (Believe it or not, 6 hours driving for 1 hour of fieldwork does sound appealing when you sit behind a lab bench most of your time!). However, even though I had over a month to prepare, I still forgot my rain boots and ended up with a wet foot. The owner kept saying “This is a fish farm you know. You’re going to get wet.” and “Don’t you go falling in there, I don’t want to have to come in after you!”.

strands of yellow perch eggs in baskets.

Yellow perch eggs come out in long gooey strands.

Although it seemed that I was an inconvenience to the owner most of the time, when I arrived at the fish farm, he was surprisingly very interested in the research that we do and said “I just want to know that you are learning something”.  In addition to learning more about yellow perch, it turns out that interactions with people in the field can also surprise you!

To sink or swim – wet waders and heavy rocks

During the Fall of 2013 I was in between contracts for work and was really itching to get outside into the field. I decided I would reach out to the Rideau Valley Conservation Authority (RVCA) to see if they needed any volunteers. Luckily, fall can be a busy time for them. The water keeps flowing and there are projects in the field that still need to be done but their summer students have left for school.

I was super excited to have the chance to be in the field again. Also, I would be in the field as a volunteer, meaning the whole project wasn’t resting on my shoulders and my decisions. This was going to be easy right??

One project I helped out with was monitoring benthic invertebrates (or “bugs”) that inhabit streams. We put on our waders and used a net to “sweep” the bottom to catch whatever bugs were living in the stream. The composition of species found in the streams can help determine the health status of a stream. We sampled in streams that were in a natural state and ones that were impacted by residential areas (guess which type was my favourite to sample!). A lot of the natural streams were fast flowing which made it hard to stand upright at times. However, I didn’t mind tipping over when the water was clear – it was only in the human impacted streams where I hoped that I did not take a wrong step.

On the boat with buckets of gravel.

Ready to lift heavy rocks – still smiling!

There was one artificial stream where the water level didn’t look too high. So as the eager volunteer, I said I would bring the measuring tape to the other side. I took a few steps and my boots started to stick a bit to the bottom. I didn’t think too much about it, as I didn’t want to be that volunteer who couldn’t make it across this small stream. As I got closer to the middle of the stream, the bottom dropped off quicker and I was sinking more into the clay bottom. At the deepest point, the water level was almost at the top edge of my waders. It was a good thing that I could not move very fast, otherwise the waves might have gone over the top (not the type of water you want to be soaked with)! Unfortunately, even though I was very careful about the top of my waders, somehow they ripped at the knee and I ended up with boots full of water anyway. In the end, wet socks were worth it to be able to say I helped sample “bugs”!

Another very cool project I helped RVCA with was The Otty Lake Fish Habitat Enhancement Project. They were improving habitat by putting gravel in small piles in the lake and fixing old branches and trees in cement to sink into the lake. This created gravel piles that fish species such as bass could use as nesting sites, while the cemented branches and trees provided shelter from predators. Needless to say, my arms were very sore after filling and carrying buckets of gravel all day! There were many times throughout the day that I thought I should quit – I was just a volunteer anyway. But there was a moment in the afternoon where a couple of the cottagers were questioning what we were doing to their lake. I do not blame them, as it must have looked very odd to see a team of about 15 people dumping buckets of something into the lake. However, once we explained to them what we were doing, they were very pleased about the efforts RVCA was taking to protect their lake and told us many stories of the fish they had seen swimming around. Being involved in these conservation efforts first hand reminded me how even the smallest thing can make a big difference in the greater story.

Two volunteers dump buckets of gravel over the side of the boat.

Dumping the big buckets of rocks in a pile in the water to create nesting sites for fish species such as bass.

 

Julia and Rachael’s excellent Muskoka adventure

This week, Dispatches from the Field welcomes guest blogger Julia Colm, a Masters student at Queen’s University with lots of stories to tell about working in Ontario’s beautiful cottage country.  For more about Julia, check out the end of this blog!

My project began as the 2014 Grass Pickerel Survey but soon became the 2014 Grass Pickerel Hunt, as my favourite Species at Risk had proven elusive. As we prepared to travel to the Muskoka region for the next leg of sampling, I felt both excited and discouraged, knowing that this population is difficult to sample because there are few Grass Pickerel and it is found in the heart of cottage country. I thought that shoreline alterations would be our biggest problem with the cottagers. I thought wrong.

Grass Pickerel (Esox americanus vermiculatus)

Grass Pickerel (Esox americanus vermiculatus)

We had spent hours canoeing a shoreline looking for a nice, weedy spot to sample, but were finding few areas that were not directly in front of someone’s cottage and had not been cleared of all aquatic vegetation. We finally found a spot off of an island that had no cottages (though it did bear a ‘No Trespassing’ sign). Since we would not be venturing onto the island itself and had no way of knowing who owned it to offer a courtesy explanation of our work, we figured we were safe to sample.

Just as we got our seine net deployed, a concerned cottager boated over to us and yelled “what are you doing?!”. We politely explained that we were from Queen’s University doing a fisheries survey of the lake. The cottager then informed us that all of the neighbours had been watching us and were ready to call the OPP; they thought we were poachers. I’ve been called many things in my life (including “homeless looking” later that day by a total stranger), but for two people who have devoted the last few years to working with Species at Risk and have been passionate about conservation their entire lives, being called a poacher was truly insulting. We kept our smiles on and apologized for worrying them, offered to show our permits, and suggested that they call the MNR tips line and alert a Conservation Officer if concerned about poachers in the future. The cottager lightened up, and generously offered to let us launch our canoe from her cottage the next day, but suggested we try to look more official and somehow make our net look less like a net. I wasn’t sure what to do with that last bit of advice, but I’m now trying to figure out how we can fly a “Queen’s University Research Vessel” pirate flag from our canoe. We apologized again and said goodbye, and as we paddled away began laughing at the thought of poachers using a canoe as a get-away vehicle. “The OPP are coming! GO! GO! GO!” [Frantic paddling]

The bugs were bad, but maybe we did look like poachers.

The bugs were bad, but maybe we did look like poachers.

Although this was our only negative interaction with cottagers, it was certainly not our only difficulty. Finding spots to launch our canoe on lakes praised for their ‘excellent boating’ proved to be an unexpected problem. One lake in particular, Grass Lake, which if the name is any indication, should offer perfect habitat for Grass Pickerel, was particularly difficult to access. The first day, we sampled a tributary of Grass Lake and caught three Grass Pickerel, and I was convinced we would not be disappointed when we got to the main body of the lake… if we got to the main body of the lake. We had driven all around the lake without any success. The closest we got to it was reaching a dead end road, and having the man who lived at the end tell us he has lived one kilometer from Grass Lake for 15 years and has yet to see it. That was upsetting. He then said that horses have gone missing in there. That was disturbing.

We concluded that we would have to access Grass Lake from the Trent-Severn Canal, an option we had been avoiding as canoeing through the canal isn’t exactly safe. We found a road that led very close to the mouth of Grass Lake, and we should only have to cross the canal to get in. Well, it turns out Grass Lake is connected to the canal through a tiny underpass below the CNR train tracks. So we now not only had to cross the canal, but then portage across the tracks with all of our gear.

Not your standard portage.

Not your standard portage.

When we crossed the canal and entered Grass Lake, we realized why it had been so difficult to get to: it was literally a lake of grass, a giant marsh. There were no cottages, and no way for non-motivated people to get to it. It was a totally undisturbed, undiscovered piece of paradise. The banks were lined with trees displaying a range of colours normally reserved for autumn, and the variety of aquatic macrophytes created a breathtaking underwater display. Fish representing almost every family were easily observed from the canoe, and I could not wait to pull up my first seine haul teeming with Grass Pickerel. Then I put my paddle in the substrate to test its firmness and my vision evaporated. My paddle slid through that silt as easily as it had slid through the water above it, and there was no way a person could stand without sinking. No wonder horses got lost. It might have been harder to get over my frustration about expending all that effort to find the lake and then having no way to sample it, except that it was such a beautiful, serene place, and even though we knew we were defeated, we paddled around the entire lake taking in its beauty.

Grass Lake, Gravenhurst, Ontario

Grass Lake, Gravenhurst, Ontario

In the end, we were redeemed at Grass Lake as one of the banks close to the mouth was clay and allowed us to do our three seine hauls. We caught several Grass Pickerel, including the first Young-of-the-Year of the year. So Grass Lake not only provided me with half of the Grass Pickerel captured during our Muskoka visit, it has also inspired me to develop new gear types for sampling fish in remote areas full of weeds and soft substrate. Canoe electrofisher, perhaps?

Julia Colm

Julia Colm completed her B.Sc in Ecology at the University of Guelph in 2010 and is currently working on her M.Sc at Queen’s University. She is interested in management and conservation of freshwater fisheries and her work at Queen’s focuses on the biology of Grass Pickerel across Ontario.