1) Andrea Erwin, Ecology, Dr. Tonn, M.Sc., oral presentation
Abstract Title: Evaluating ecosystem function before and after habitat compensation in the Canadian Arctic
A habitat compensation project, focused on improving ecological connectivity within a small 3-lake, 3-stream ecosystem, is underway for the Lac de Gras, NWT watershed as a result of diamond mine development. Our research project is assessing ecosystem functioning before and after compensation efforts and thereby the effectiveness of the compensation project using a BACI design. Habitat manipulations involved the construction of a series of step-pool structures at two streams, and one choke-and-pool structure at the third stream; three reference streams were also studied. CPOM decreased at manipulation sites after construction but to a lesser extent at the choke-and-pool site, relative to the reference sites. Woody debris decreased at the step-pool sites, and increased at the choke-and-pool sites. All three sites showed similar decreases in rates of leaf litter processing after construction. The choke-and-pool system appears more similar to reference sites than step-pool systems.
2) Julie Saby, Dr. Rebecca Case, B.Sc – Biology (499), Oral Presentation
Abstract Title: Testing Algal-Bacterial Co-culture Health with PAM Fluorometry from Small Volume Samples Grown in Microtiter Wells
Conventional methods for culturing algal strains required large volumes of culture and precise nutrient ratios. However, culturing volumes of 20 to 2 thousand milliliters can be problematic in several ways: 1) subsampling leads to variation in nutrient concentrations, 2) experiments are costly, and 3) replication with accuracy is difficult to achieve. The use of microtiter plates enables researchers to culture algae in 1 mL of media, thereby decreasing cost and allowing for extensive replication. Additionally, this technique can be modified to fit a variety of experimental aims including: algal physiology tests, bacterial-algal co-cultures, toxin screening, and vitamin screening, etc. Algal and/or co-culture samples can then be drawn from the microtiter plate wells for use in numerous laboratory procedures including microscopy, flow cytometry, and Pulse-Amplitude-Modulated (PAM) fluorometry. The combination of the microtiter plate format and PAM fluorometry allows for non-invasive multiple rapid measurements of health and chlorophyll content of algal and bacterial co-cultures.
3) Joshua Miller, Systematics & Evolution Coltman, PhD, Oral presentation
Abstract Title: Identity disequilibrium and its relation to heterozygosity fitness correlations
Heterozygosity fitness correlations (HFCs) have often been used to detect inbreeding depression, under the assumption that heterozygosity is a good proxy for inbreeding. However, meta-analyses of the association between fitness measures and individual heterozygosity have shown that often either no correlation is observed, or the effect sizes are small. One of the reasons for this may be the absence of variance in inbreeding, a requisite for generating general-effect HFCs. Recent work has highlighted identity disequilibrium (ID) as a measure that may capture variance in the level of inbreeding within a population, however, no thorough assessment of ID in natural populations has been conducted. In this meta-analysis we assess the magnitude of ID from 50 previously published HFC studies, and its relationship to the observed effect sizes of those studies. Across the majority of studies ID values were not significantly different than zero. Despite this, we found that the magnitude of ID was associated with the average effect sizes observed in a population. These low values of ID translated into low expected correlations between heterozygosity and inbreeding, and suggest that many more markers than typically used are needed to robustly detect HFCs.
4) Jason Gardiner, Plant Biology/Enrico Scarpella, Ph.D, Poster and presentation
Abstract Title: Control of leaf vein formation
The beautiful and diverse patterns of veins in plant leaves have fascinated biologists for centuries. In developing leaves, files of cells that will differentiate into veins are selected from within a population of cells of similar shape and size. Molecular details of the selection process are scarce, but available evidence suggests that the process terminates with the activation of expression of the HOMEODOMAIN LEUCINE ZIPPER III gene Arabidopsis thaliana HOMEOBOX8 (athB8) by the Auxin Response Factor MONOPTEROS. I will present and discuss new evidence to define more precisely the role of MP-dependent auxin signaling and athB8 in leaf vein formation.
5) Christopher L. Cahill, Ecology-Evolution, William M. Tonn, M.Sc., Oral
Abstract Title: Modeling the Potential Effects of Climate Change on Arctic Grayling in Alberta
Concerns regarding effects of climate warming on aquatic ecosystems often focus on stenothermic coldwater organisms near the southern limits of their distribution. Arctic Grayling (Thymallus arcticus) is a northern coldwater fish that reaches its southern geographical limit in Alberta (except for disjunct remnant populations in Montana), where it is a species of special concern. Our objectives were to 1) project future air temperature trends across the range of grayling in Alberta, 2) identify the resulting thermally suitable habitat, and 3) relative to its current distribution, quantify landscape level losses of thermally suitable habitat for grayling over three time periods (2010-2039, 2040-2069, and 2070-2099), using an ensemble of 15 General Circulation Models recommended for use in Alberta. Modeling results suggest anthropogenic warming will greatly reduce the amount of thermally suitable habitat available to Arctic Grayling in Alberta during this century, and could increase its extirpation risk in many areas.
6) Kyle Welsh, Ecology/Paszkowski, M.Sc., oral presentation
Abstract Title: The Influence of Terrestrial Habitat on Western Tiger Salamander (Ambystoma mavortium) Distribution in Central Alberta
It is well known that Ambystomatid salamanders require terrestrial foraging and overwintering habitat adjacent to natal breeding ponds. However, current knowledge of their terrestrial requirements remains scant and of limited scope. Populations in Alberta are of special concern and to date there has been little work on this species in the province and in Canada. In this study, I examined salamander presence in 43 known and potential breeding ponds in relation to adjacent land cover, soil characteristics, and mammal burrow density. Ponds were selected to ensure minimal aquatic habitat variation and a wide range of terrestrial variation. Each pond was sampled three times from May through July to account for variation in detectability. Salamanders were detected at 23 sites. Results were analyzed with logistic regression and models were selected with AIC. Presence at a site was associated with mammal burrow density and sandy soil, suggesting that access to the subterranean influences salamander distribution more so than land cover in a region that is not limited in aquatic habitat.
7) Emily Durkin, Dr. Lien Luong, Ph.D., Oral
Abstract Title: Effect of host sex on the chewing louse community found on a population of brown-headed cowbirds
Chewing lice (Phthiraptera) are permanent residents of their hosts and are transferred nearly exclusively through direct forms of body contact such as copulation and care of young. For most bird species, direct contact generally occurs with those of the same species. Brown-headed cowbirds (Molothrus ater) are brood parasitic and thus have the opportunity to come in contact with different bird species and their lice. The sexes engage in different behaviors that could affect louse exposure. I investigated the effect of host sex on chewing louse prevalence, intensity and diversity of brown-headed cowbirds. Four hundred and one brown-headed cowbirds were collected in Michigan and examined for lice. Lice were collected by blowing compressed air on euthanized brown-headed cowbirds in an enclosed chamber. Lice that had fallen from the brown-headed cowbirds within the chamber were counted and identified. Sixty percent of the brown-headed cowbirds in this population were infected (242/401) with at least one genus of chewing louse. Five louse genera (Brueelia, Philopterus, Menacanthus, Myrsidea and Machaerilaemus) were identified. Significantly more males were infected (189/293) with chewing lice than females (53/108). Although not statistically significant, the male population had greater louse intensity than female. Chewing louse diversity was similar between the sexes.
8) Nathan Lauer, Dr. Zwiazek, PhD, Oral presentation
Abstract Title: Assessing the relationship between seagrass health and habitat quality with wasting disease prevalence in the Florida Keys
Marine pathogens of the genus Labyrinthula have been identified as the cause of wasting disease in seagrass systems in both temperate and subtropical regions. An understanding of the association between environmental factors and the prevalence of wasting disease in seagrass meadows is important for elucidating plant–pathogen interactions in coastal environments. We conducted a survey of 7 turtle grass-dominated beds within the Florida Keys National Marine Sanctuary to assess the relationship between environmental and biological parameters on seagrass health. All sites contained Labyrinthula spp.; the most pathogenic strain was obtained from an anthropogenically impacted site. Leaf and total biomass, in addition to root/rhizome carbon content, canopy light and % light transmitted, all displayed strong negative correlations with a wasting index (WI). It was noted that many of the same environmental measurements that showed negative correlations with WI also isplayed strong positive correlations with canopy light levels. These data suggest that light availability may be an important factor that has previously been understated in the seagrass disease literature yet warrants more attention with respect to turtle grass susceptibility to infection.
9) Melanie Dickie, Ecology/Stan Boutin, M.Sc., presentation
Abstract Title: Understanding and mitigating grey wolf (Canis lupus) use of linear features
Human disturbances can impact predator-prey relationships by influencing the numerical and functional response, consequently affecting predation rates. For example, oil and gas exploration in Northern Alberta is hypothesized to increase wolf (Canis lupus) predation on boreal woodland caribou (Rangifer terandus caribou) by increasing spatial overlap, increasing wolf populations, and increasing foraging efficiency. Wolves use linear features such as seismic lines, pipelines, and roads disproportionately to increase movement efficiency which impacts their functional response by increasing prey encounter rates. Restoring linear features is one option to mitigate an increased foraging efficiency, but first it is imperative to understand which features are preferred, how they are used, and their impact on the functional response. My research aims to assess if wolves select linear features, and if so which types of linear features, which biophysical attributes are important in determining their use, and how the use of these features impacts their movement behaviors. This knowledge can aid mitigation strategies by targeting specific features for reclamation and linear deactivation, allowing for more effective use of conservation resources.
10) Greg Funston, M.Sc. Program. Supervisor: Philip Currie (Systematics and Evolution) Oral Presentation
Abstract Title: Understanding Alberta’s caenagnathids: insights on anatomy and taxonomy from a new, articulated specimen.
The Caenagnathidae (Dinosauria: Oviraptorosauria) is a family North American dinosaurs that was poorly known until recently. Although the first specimens were described in 1924, only now have we begun to understand their anatomy and biology. Isolated fossils representing nearly every element of caenagnathids are known, but understanding how they relate to each other taxonomically is difficult. Only two partial skeletons (TMP 1979.20.1 and ROM 43250) have been described, and their diagnostic elements do not overlap, making relationships unclear. Many mandibles, phalanges, and metatarsals are known, but vary greatly in morphology and size, and are isolated or fragmentary. A new specimen (TMP 1993.051.0001), however, may change our view of caenagnathid taxonomy. First uncovered in 1993 and initially mistaken for an ornithomimid, the specimen sat unprepared for 15 years, until it was finally prepared in 2008. Besides being articulated, the specimen is well preserved and nearly complete. The talk will compare TMP 1993.051.0001 to other caenagnathid specimens, particularly ROM 43250 and TMP 1979.20.1, and will present preliminary ideas regarding Alberta’s caenagnathids and their taxonomy. Furthermore, the talk will present the first complete reconstruction of an Albertan caenagnathid.