During the active season at QUBS we try to feature student researchers from different labs and universities so that you may come to know about the amazing research being undertaken at QUBS.
July 6 - 12 May 2013
Project title: Reduction of Turtle Bycatch by Means of Gear Modification in a Small-scale Inland Commercial Fishery.
(Supervisors: Steven Cooke, Dept. of Biology, Carleton University; Gabriel Blouin-Demers, Dept. of Biology, University of Ottawa)
April 7 2012 - July 5 2012
Project title: Microclimatic predictors of call phenology of eastern Ontario frogs.
(Supervisor: Dr. Stephen Lougheed - Queen's University)
Amphibians are considered indicators of ecosystem health because of their sensitivity to environmental change due in part to their semi-permeable skin and aquatic developmental requirements. Mirroring many other taxa, temperate frog species in recent years have increasingly initiated their breeding seasons earlier, presumably in response to higher mean daily temperatures and the earlier onset of spring. Conventional studies of climate change to date have used anecdotal records of environmental trends to interpret phenological events.
Despite the insight that this approach has provided, it is not ideal because the data are often too broad-scale or piecemeal to allow detailed insights into factors that affect breeding behaviour. For example, many species of frogs occur in a variety of semi-aquatic ecosystems, suggesting that different conspecific populations may be subject to different environmental influences. Studying climatic variation at a local and regional scale simultaneously could help to attain greater accuracy at predicting frog phenology and to understand which factors best predict the onset and peak of breeding. My master’s research aims to quantitatively assess the effects of multiple abiotic environmental factors on calling activity of an anuran community on a small scale (daily) for an entire breeding season. Variables of interest include how annual variation in temperature, dew point and relative humidity influences species’ abundance of calling males. Male chorusing intensity will act as a measure of reproductive effort for the species.
In 2008, 12 automated survey stations were established; each consisting of a digital audio recorder programmed to record choruses at dusk, and a data loggers to measure relative humidity and air temperature. In 2009 (beginning in March), the number of survey sites increased to 21. In 2010, 19 of the sites were revisited from the previous year. In 2011 the survey expanded at the northern and southern parts of the sampling area, totaling 25 sites, and included soil and water temperature gauges in 10 locations as well as rain temperature gauges at 3 locations. This year I have put out 26 stations beginning again in March and will be obtaining relative humidity, air, soil and water temperature readings at nearly all locations. Many of these locations across years have been placed in wetlands within and surrounding the biological station as well as in national parks.
I hope these long-term data will provide key insights into the proximate factors that control initiation of breeding for eastern Ontario anurans, and enhance the possibility for adaptive responses to changing temperature regimes. My study also will allow for more accurate predictions of anuran responses to continued climate change. If you would like to learn more about my research, you can contact me at firstname.lastname@example.org.
Sept. 1 2011 - April 7 2012
(Supervisors: Dr. David Green - Simon Fraser University & Dr. Joseph Nocera - Trent University)
Many species of migratory birds are experiencing population declines, but certain guilds appear to have been affected more than others. One such group is that of aerial insectivores, species that capture their prey, mostly flying insects, while on the wing. Aerial insectivores include species of swallows, flycatchers, swifts, and nightjars. Although species of aerial insectivores may differ in many of their life history traits, they all have one thing in common: their diet consists of flying insects. Given their shared diet, food availability could be a major factor in this guild-wide decline. There are, however, other shared characteristics that might contribute to population declines including migratory behavior and use of relatively open habitats.
One of the least studied of Ontario’s aerial insectivores is the eastern whip-poor-will (Caprimulgus vociferous). This nightjar was once abundant in rural Ontario, but has become rare in much of the south and less common on the shield of central and eastern Ontario. My PhD research explores possible causes of the decline in whip-poor-wills including habitat loss, food availability and changing climate. This spring and summer I captured whip-poor-wills and outfitted them with radios so I could track their movements on the breeding grounds. I fitted other whip-poor-wills with geolocation loggers for tracking them to their wintering grounds. I located nests at night using eye-shine of incubating birds and monitored those nests using video surveillance. Habitat characteristics and food availability will be sampled both here at the biological station, where whip-poor-wills remain abundant, and in sites in Ontario were whip-poor-wills have disappeared. Finally, chemical evidence of winter diet from claw and feather tissue samples and migratory routes identified using tracking devices will be used to assess potential threats to whip-poor-wills during the non-breeding season.
This research will continue through 2013 and will require tracking of birds both on QUBS-owned land and surrounding properties; therefore if you live in the vicinity of QUBS and would like to offer permission for me and my field crew to conduct research on your property please contact me at email@example.com.
May 29 - Sept. 1
(Supervisors: David Sherry and Scott MacDougall-Shackleton, Advanced Facility for Avian Research, University of Western Ontario)
Project title: Intersexual differences in brood parasites: psychological and hormonal correlates of sex stereotyped behaviour.
During B.Sc. (Hon) and M.Sc. degrees at the University of Manitoba, I studied the anti-parasite defences used by hosts of avian brood parasites. Primarily, I examined cues used by yellow warblers (Dendroica petechia) to reject eggs of brown-headed cowbirds (Molothrus ater). Now, for my PhD, I am studying the parasites themselves. The female brown-headed cowbird produces the egg and is the only the member of the pair to search for nests, whereas males provide only sperm, competing for females. Because of these behavioural differences, female brown-headed cowbirds have a larger hippocampus relative to males. The avian hippocampus is responsible for spatial memory performance. The goal of my research is to examine the spatial memory differences between the sexes and hormonal correlates that may influence performance in a spatial task.
First, I plan to train the cowbirds to use touch screens. A delayed matching to sample task will assess the birds’ ability to remember the location of a shape on the screen. Second, I plan to test the birds’ performance in a food cup exercise. An array of cups will be presented to the birds with their contents hidden. For each bird, only certain cups will contain food rewards. This task is meant to test how long birds can remember a certain location. Females are predicted to outperform males on both tasks. Additionally, hormone levels, such as estradiol and testosterone levels, are predicted to influence spatial memory performance, as has been shown in another avian species.
My research is meant to examine the effects of differential selection between the sexes in a single species. Also, by better understanding brood parasites, it is possible to better protect species they parasitize.
April - May 28
(Supervisors: Steven Cooke, Carleton University and Gabriel Blouin-Demers, University of Ottawa)
Project title: Bycatch, or the incidental capture of non-targeted organisms, is a common occurrence in commercial fisheries.
Aside from the sustainability of the targeted catch, reducing bycatch and the associated mortality is one of the most pressing conservation issues for fisheries worldwide.
Bycatch mitigation efforts are mostly focused on marine systems, yet inland fisheries also documents bycatch mortality, specifically with air-breathing organisms (e.g., birds, mammals, and turtles).
My research focuses on an inland hoop net fishery in southeastern Ontario, in which the capture and mortality of freshwater turtles, including at-risk species, have occurred. Life-history characteristics of turtles make them very susceptible to population declines and the additional adult turtle mortality from fisheries is a conservation issue. Thus my main research goal is to determine ways to mitigate or reduce freshwater turtle mortality that is associated with inland hoop net fisheries.
During this spring, summer, and fall, I have been looking at modifying hoop nets to either restrict turtles from entering nets, to allow access to air, or to allow turtles to escape, all without affecting target fish catches. I am also using blood physiology of the turtles to determine the best method to release a captured, alive turtle.
By setting nets over the year, I will be gathering seasonality data to determine the most vulnerable time for turtles to be captured.
Finally, I have been marking/recapturing painted turtles to obtain a population estimate to use towards modeling the long-term effects of fisheries related mortality on turtle populations.
This work will hopefully contribute towards reducing the impacts of commercial fisheries on freshwater turtles, specifically at-risk turtle species.
August 19th - November 29
(Advisor: Mark Forbes; Carleton University)
Evolutionary ecology of a multiple parasite-host system; damselflies, larval water mites and gregarines
Parasitism is documented in most living organisms. Most parasitic work has been done on vertebrates. However invertebrates are also parasitized and these parasites could be potentially successful bio-control agents for pests. However, with the lack of knowledge about these parasites, we need base line data. Damselflies become an excellent study system because they are host to many different types of parasites both external and internal and they span aquatic and terrestrial habitats. Most commonly they are infected by larval water mites (arachnids) and gregarines (protozoan apicomplexans), but also no-see-ums (diptera), trematodes, cestodes and nematodes.
My research is focused on determining the patterns of parasitism at different spatial and phylogenetic scales. The main questions in my research revolve around whether parasites follow their hosts in the evolutionary sense or an ecological sense. Is the host-parasite relationship based on phylogenetic relatedness between the host species or based on ecological variables, such as habitat preference by the parasite and host? In order to determine phylogenetic relatedness, I am sampling species pairs across the zygoptera to see how parasitism loads and assemblages differ. For the ecological relatedness, I will focus on bog and marsh damselflies, and will determine whether parasite loads and assemblages are more similar when the host populations are in closer proximity. For example, I am interested in knowing whether the parasite communities in a particular host species is more similar in two bogs that are geographically closer together from one that is further away. In order to do these projects, I will need to use a slew of techniques; ranging from morphological identification tools to molecular methods.
This summer, I am undertaking three main projects. My first focus is to discern whether nymph (larval) damselflies are infected by the same internal parasites as the adults. Second, I am collecting host species pairs to begin comparing parasitism loads and parasite assemblages. Third, I am comparing at what rates and with what kind of success the host is able to defend itself from external and internal parasites. We are determining melanisation rates, the main defence mechanism of insects, to external and internal parasitism.
I look forward to determining the patterns of evolution of this multiple-parasite host system.
July 12th - August 19th 2010
(Supervisor: Dr. Andrew Mason, University of Toronto)
Night flying insects face the risk of predation by bats, who hunt at night using ultrasound to sense their environment. Many insects can detect and evade bats with ears tuned to the high frequency echolocations calls. The neurologically simplest insect ear belongs to moths in the notodontid family. By examining physiological and physical properties of the ear I am researching how the ear produces a signal, how this signal encodes sound, how bat echolocation calls are identified by the CNS, and how that information affects flight behaviour.
In a recently published study conducted at QUBS from 2007-2009 (| here |) we showed that local notodontid moth Nadata gibbosa is capable of listening for all 7 local bat species. We also discussed how a moth with such a simple ear would be able evade or avoid bats of each local species, based on the peak frequency of their calls. Moths can evade bats by diving out of the way of close (loud) bats and avoid them by more calmly turning away from bats that were further away (quieter).
Using three-dimensional flight path reconstruction of moths responding to bat-like ultrasound and microphone arrays to measure source level intensity of local bats we are now hoping to gain further insight into the bat avoidance response. We hope to further define the sensory response properties responsible for both avoidance and escape responses.
Finally, we are also experimentally manipulating notodontid tympanic cavity volume in order to determine the extent to which its resonance properties tune the ear.
May 22nd - July 11th 2010
(Advisor: Beth MacDougal-Shakleton; University of Western Ontario)
Across taxa we observe sexual dimorphism, in which males have some elaborate secondary sexual characteristic and females are the choosy sex. Indicator models of sexual selection propose that these elaborate ornaments may advertise direct and/or indirect benefits for females and thus serve as honest indicators of male quality. This may extend to the advertisement of a males ability to resist infectious disease. My research is based in sexual selection and ecological immunology. I am examining how song complexity, a sexually selected trait in song sparrows (Melospiza melodia), may predict disease resistance and relative current health status. I am assessing this by performing a variety of complementary assays which measure various components of constitutive immune function.
This spring I have been recording male song and performing assays in a rudimentary laboratory set up in the field. One assay is a microbicidal assay that looks at the ex vivo ability of blood to kill a given pathogen. The other examines the phagocytic activity of macrophages. Later this Summer I will be quantifying other immune system components from samples collected.
Spending time recording the song of this species has lead to an enormous appreciation for the complexity of this vocalization. I look forward to further analyzing this multi-component signal.
April 1st - May 22nd 2010
(Supervisor: Paul Martin, Queen’s)
Recently diverged species often share many ecological traits and strategies inherited from their common ancestor. Because of this, recently diverged species may use the same habitats and cluster spatially within communities. Alternatively, fitness costs resulting from overlapping resource needs may lead to recently diverged species segregating by habitat. As a result of differing degrees of similarity, patterns of spatial and habitat overlap between closely-related species should change through time. My research investigates how recently diverged species partition space and habitat, and how those patterns of spatial partitioning and habitat use change over evolutionary timescales. I work with the Dendroica wood-warblers, a group of small insectivorous passerines that have featured prominently in the ecological literature.
During the spring/summer of 2008 and 2009 I mapped territories and quantified habitat characteristics for nine sympatric species of Dendroica at QUBS. I found that recently diverged species frequently overlapped their breeding territories and habitats. By contrast, more distantly related species did not overlap their breeding territories or their habitats as often. Patterns of overlap among Dendroica appear to change as time since divergence from a common ancestor increases. When recently diverged species come into sympatry they do not differ in habitat, but over time differences in habitat arise and more distantly divergent species do not overlap.
This year I will work with Paul Martin and Raleigh Robertson using a combination of point counts, song playback, colour banding, and GIS mapping to estimate the population size and density of cerulean warblers (D. cerulea) across all QUBS properties. Although my research focuses on birds, I have a wide interest in many aspects of natural history, particularly trees, pteridophytes, orchids, dragonflies, orthopterans, butterflies, beetles and any wild edible.
(supervisor: Chris Eckert, Queen's).
Plants are often viewed as passive and perhaps boring organisms, but their sessile nature is in fact an opportunity for bewildering adaptations. I am interested in how sessile organisms such as flowering plants determine the fate of their gametes. Flowering plants have been widely studied because they often have intricate floral structures that help constrain and control its interactions with pollinating vectors.
My on-going Ph.D. thesis project investigates just one of these floral structures and its effects on the reproductive success of the Red Columbine (Aquilegia canadensis). Herkogamy is the spatial separation of male and female reproductive organs, and this trait functions to reduce selfing (the plant producing offspring through its own ovules and pollen). The Red Columbine has substantial variation in herkogamy even though producing selfed offspring is very disadvantageous because they almost never survive till reproduction. The maintenance of this variation may be due to contrasting directional selection on herkogamy for male and female reproductive fitness components. Within-individual sexual conflict may explain the seemingly sub-optimal large variation in herkogamy.
May 22nd-June 1st
(Supervisor: Laurene Ratcliffe, Queen's).
Transitive inference (TI) is a psychological task one thought to be exclusive to humans. It involves a subject being given a transitive (i.e. linear) relationship between three or more objects (e.g. A > B, B > C) and then subsequently inferring the relationship between two of those objects not compared directly (i.e. A and C). However, after three decades of research, some species of animals have been able to demonstrate TI tasks in laboratory-based experiments. But these experiments are fairly far-removed from the natural settings in which the ability evolved in the first place, perhaps as a useful tool for living in groups (if you can reason that your groupmate Bob dominates you, but Steve dominates Bob and therefore must dominate you, then you can avoid costly fights with Steve in the future).
Black-capped Chickadees (Poecile atricapillus) may be an ideal species to test for TI in a more natural setting as they utilize linear dominance hierarchies (one bird is dominant, with descending ranks for the rest of the birds in the flock). For my Masters work I will be attempting to see if chickadees can demonstrate TI in semi-natural conditions by judging the relative rank of individuals they’ve seen competing separately, but not together. To do this, I will be running both aviary trials during the winter and playback experiments during the spring, using banded chickadees from the QUBS property and surrounding areas. If I can demonstrate TI in these conditions, it would be some of the first evidence for its natural role in wild.
(Supervisor: Steve Cooke, Carleton).
Predation is considered one of the greatest costs of reproduction. Many animals become more prone to predation due to behaviours associated with reproduction such as mate searching or mate signaling. Predators have become specialized and will often capitalize on these signals, while reproducing individuals have also evolved avoidance tactics. Alternatively, there are systems where reproducing individuals provide parental care to developing and vulnerable offspring and have low risk of individual predation. Here, parents invest heavily into offspring in order to increase the probability of offspring survival. My PhD research uses the paternal-care providing smallmouth bass (Micropterus dolomieu) as a model to examine the effects of varying nest predation. Using a natural gradient in nest predation pressure across 6 lakes in close proximity to QUBS, I am testing whether this gradient influences the behaviour and physiology of parents as well as offspring.
To date, I have shown that males from lakes with higher nest predation pressure spend more time engaged in antipredator activities relative to males from lakes with low predation pressure. Physiologically, males from lakes of low and high predation pressure do not differ in anaerobic or aerobic muscle capacities. Currently I am using electromyogram transmitters to compare the overall swimming activity of males in high and low nest predator systems. There is evidence that parents in lakes with high predation pressure must invest more heavily into their offspring than males in low nest predation pressure. In a laboratory setting, offspring from lakes with high predation pressure are better able to avoid a natural nest predator. This predator avoidance behaviour is lost in lab-reared offspring. We are still examining the physiological differences among offspring across the natural nest predation gradient, as well as their escape responsiveness.
Together, my PhD research will contribute to parental care theory by providing a novel model with which to examine individual and intergenerational effects of nest predation pressure.
June 19th-August 4th
(Supervisor: D. Dudley Williams, University of Toronto).
Food webs depict consumer-resource interactions between individuals within a habitat. Food webs have long been considered static entities without the incorporation of temporal and spatial variability or the influence of the surrounding landscape. A current paradigm in food web ecology is to understand how environmental variation influences food web structure and function and why, mechanistically, food chain length changes within an ecosystem. Temporary waters are diverse, abundant in the landscape, extremely heterogeneous in time and space, and they host numerous species of plants, invertebrates, and amphibians. Therefore, these habitats make excellent arena’s to study food web dynamics.
My research has three main objectives, one; to characterize food web structure and function using stable isotopes of nine water bodies along a hydroperiod gradient ranging from temporary woodland ponds to permanent marshes. The hydroperiod gradient determines species composition and predation pressure, which may influence food web structure. The second objective is to document the niche variation and ontogenetic diet shifts of amphibian larvae from ponds along the hydroperiod gradient to understand how hydroperiod influences diet and food web structure. The third objective is to quantify the energy flow from temporary ponds via amphibian metamorphosis and insect emergence and the incorporation of aquatic-derived energy into the terrestrial food web.
Results from my first field season (2008) show ponds vary considerably in food chain length, species composition, and productivity. Ponds having an intermediate length hydroperiod had the longest food chains and species exhibited higher nitrogen stable isotope signatures resulting in higher trophic positions. Ontogenetic diet shifts are common in tadpoles but each species exhibits differing magnitudes of change.
August 5th 2009 - April 11th 2010
(Supervisor: Beth MacDougall-Shackleton, Western).
The relationship between genetic diversity and fitness has been and continues to be a source of interest and debate amongst scientists. Inbreeding has been associated with decreased reproductive success and immune system strength, but evidence for individual heterozygote advantage and inbreeding avoidance is mixed. I aim to study whether there is a correlation between heterozygosity and fitness in a population of song sparrows near Queen’s University Biological Station.
To assess the influence of genetic diversity on fitness and behaviour I will use 18 genetic markers and several indicators of survivorship and reproductive success. If heterozygosity is associated with increased fitness, I will study how this might influence behaviour. Specifically, I will look at whether females are choosing more genetically dissimilar males for their social or extra-pair mates, and whether parents will invest more time and energy in offspring who are more heterozygous. To assess parental care, I banded all adults with a unique Passive Integrated Transponder (PIT) tag, and then placed an antenna at each nest for two days. The antennas record when each parent visits the nest and for how long, allowing me to have a comprehensive account of the time males and females are spending at their nests. Nest visitations to incubate, feed or defend young are very energetically expensive for parents, but essential for the nestlings’ development. Greater parental care in the nest will increase the nestlings’ chances of successfully fledging and surviving their first winter.
Through this project I hope to contribute to our understanding of how genetic and environmental factors shape fitness and behaviour.