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Schamp B.,Algoma University | Horsak M.,Masaryk University | Hajek M.,Masaryk University
Journal of Animal Ecology | Year: 2010

1. We investigated whether coexisting snail species in 145 treeless fen communities in the Western Carpathian Mountains differed more in size and diet than would be expected by chance, as predicted for traits commonly associated with competition and differential resource acquisition under limiting similarity theory. 2. Contrary to expectations, coexisting snail species were no more different in body size than expected by chance under a null model. However, variation in body size played a significant role in structuring snail communities: coexisting snail species were significantly more similar with respect to body size. 3. We developed two new test statistics to expand our investigation of limiting similarity to include diet, a nominal trait. We tested whether communities of snails were characterized by a greater richness of diet, and whether different diets were represented more or less evenly within communities. Communities of snails were significantly less evenly distributed than expected by chance, with detritivores being over-represented relative to predatory strategies. 4. We also examined the effect of water pH and conductivity, herbaceous cover, and bryophyte and vascular plant richness, on these trends by examining how the effect size of our tests varied across these gradients. Convergence in species size increased with increasing habitat pH. Specifically, smaller snail species were over-represented in fen communities in general, and this effect was accentuated in increasingly calcareous fens. 5. Theory predicts that traits related strongly to environmental conditions are more likely to be convergent. Our findings support this suggestion, as small snail species have an advantage in tolerating freezing conditions over winter when refuges are limited. 6. These results add to the growing body of literature demonstrating that variation in body size and diet play a strong role in structuring communities, although frequently in ways not predicted by limiting similarity theory. Finally, our results increase our understanding of how species are assembled non-randomly into communities with respect to important traits. © 2010 The Authors. Journal compilation © 2010 British Ecological Society.


News Article | February 22, 2017
Site: www.gizmag.com

If you've spent much time around North America's Great Lakes, then you're probably familiar with the sea lamprey. The eel-like fish first made its way into the lakes from the Atlantic Ocean in the early 20th century, via shipping canals. Since then, it's become a destructive invasive species, depleting stocks of native fish by parasitically feeding on their blood. Thanks to recent research, however, there may be new hope for controlling lamprey populations – and it involves turning one of their natural defence mechanisms against them. Currently, the main approach to lamprey control involves adding a chemical "lampricide" to the tributary streams that serve as lamprey nurseries. The chemical is designed to kill larval lampreys, while not harming most other aquatic organisms. According to a team at Montreal's Concordia University, though, administering lampricide is a costly and labor-intensive process, plus there are concerns that it could harm the ecosystem. Low concrete dams have also been built across the mouths of the tributaries, which the poorly-jumping adult lampreys have difficulty getting past when swimming upstream to breed. Again, though, building dams isn't a simple or cheap process. Additionally, although the dams are typically equipped with sneak-around "fish ladders" at the sides, it's possible that native species of fish will likewise be thwarted by the structures. That brings us to the Concordia scientists' latest research. They've collected a compound that lampreys emit into the water when frightened or injured, which alerts other lampreys to stay away because danger is nearby. It had previously been suggested that this substance could be used to keep lampreys away from their own spawning grounds, thus stopping them from reproducing. In a recent test of that theory, a team led by Prof. Grant Brown tagged hundreds of lampreys with transponder tags, then released them near the mouth of a large stream – not far up that stream, a nursery tributary flowed into the main stream. Initially, 60 percent of the lampreys swam up the main stream, while 25 percent proceeded to swim up the tributary. The scientists then added the "alarm cue" extract to the water in the tributary, allowing it to flow down into the main stream. Once they had done so, only 40 percent of the tagged lampreys entered the main stream, and only 3 percent swam up the tributary. It is now hoped that the system could be combined with the use of pheromones that lampreys use to attract mates. In this way, the fish would be both scared away from their spawning grounds and drawn to another location, where they could then be trapped. The research, which also involved scientists from Ontario's Algoma University and the United States Geological Survey, was recently described in a paper published in the journal Fisheries Management and Ecology.


Schamp B.S.,Algoma University | Aarssen L.W.,Queen's University
Journal of Vegetation Science | Year: 2014

Question: Experimental evidence suggests that competition among plant species is generally hierarchical and that relatively large species are at a competitive advantage when competition is predominantly above-ground. However, regional species pools are dominated numerically by relatively small plant species, and small species generally have higher local densities of resident plants within natural communities. One explanation is that larger plant species suffer disproportionately more under effects of intra-specific competition (i.e. greater density dependence). We tested this prediction using ten herbaceous plant species in a competition experiment. Location: Kingston, Ontario, Canada, glasshouse. Methods: Using a glasshouse experiment, we tested whether relatively large species suffer disproportionately more in monoculture relative to mixtures of all ten herbaceous plant species. We measured the effects of competition on biomass production and survival by monitoring both in monocultures and mixtures of our species. Results: Larger plant species suffered more under intra-specific relative to diffuse inter-specific competition in terms of survival; however, the slope of this relationship was not significantly greater than one, indicating that larger species did not suffer disproportionate density-dependent suppression. Conclusions: Our results support a role for size in plant competition, but also indicate that this role is reduced because relatively larger species suffer greater density-dependent mortality when competing with other, equally large plants. As such, size-based competitive hierarchies may not function as clearly in natural systems because the increased negative density dependence for larger species contributes to balancing out competition across size hierarchies. © 2013 International Association for Vegetation Science.


Hornstein H.A.,Algoma University
International Journal of Project Management | Year: 2015

Project management processes and the training of new project managers (PM) must consider the impact of organizational change on the success and failure of project implementations. The case for requiring project managers to be conversant with organizational change management (OCM) is made by the author by reviewing supportive literature. In addition, PM certifying agencies like PMI and IPMA are strongly encouraged to include education on OCM to the certification process for new PMs. © 2014 Elsevier Ltd and Association for Project Management and the International Project Management Association.


Terrion J.L.,University of Ottawa | Aceti V.,Algoma University
Research in Learning Technology | Year: 2012

While technology - in the form of laptops and cellphones - may be the cause of much of the distraction in university and college classrooms, some, including the personal or classroom response system (PRS/CRS) or clicker, also present pedagogical opportunities to enhance student engagement. The current study explored the reactions of students to clicker implementation in a large, introductory chemistry class. During the final class of the semester, 200 students in an introductory chemistry class responded to an attitudinal and informational student survey using both Likert-type and non-Likert type questions to evaluate their perception of the implementation of the clickers and their impact on student learning and engagement. The results demonstrated that, when implemented effectively, clickers contribute to greater student engagement and, ultimately, an opportunity for professors to enact best practices in higher education pedagogy. This study points to the importance of effective pedagogy in making clickers worthwhile. © 2012 J. Lennox Terrion and V. Aceti.


Zhang C.,Algoma University | Kovacs J.M.,Nipissing University
Precision Agriculture | Year: 2012

Precision agriculture (PA) is the application of geospatial techniques and sensors (e. g., geographic information systems, remote sensing, GPS) to identify variations in the field and to deal with them using alternative strategies. In particular, high-resolution satellite imagery is now more commonly used to study these variations for crop and soil conditions. However, the availability and the often prohibitive costs of such imagery would suggest an alternative product for this particular application in PA. Specifically, images taken by low altitude remote sensing platforms, or small unmanned aerial systems (UAS), are shown to be a potential alternative given their low cost of operation in environmental monitoring, high spatial and temporal resolution, and their high flexibility in image acquisition programming. Not surprisingly, there have been several recent studies in the application of UAS imagery for PA. The results of these studies would indicate that, to provide a reliable end product to farmers, advances in platform design, production, standardization of image georeferencing and mosaicing, and information extraction workflow are required. Moreover, it is suggested that such endeavors should involve the farmer, particularly in the process of field design, image acquisition, image interpretation and analysis. © 2012 Springer Science+Business Media, LLC.


Gala T.S.,Algoma University | Melesse A.M.,Florida International University
Catena | Year: 2012

The provincial wetland ("status quo") maps of the Prairie Pothole Region, Central Canada, do not adequately depict wetland resources and properties. Using satellite remote sensing data from both LANDSAT Enhanced Thematic Mapper Plus (ETM+) and RADARSAT-1 Synthetic Aperture Radar (SAR) results in a more complete picture, although using both sources together is better than when either source is used alone. This study integrates LANDSAT ETM+, RADARSAT-1 SAR, and LIght Detection And Ranging (LIDAR) data, taking advantage of the synergy in their integration. A simple density slicing of the ETM-5 band was used to map inundated areas from LANDSAT ETM+. A fuzzy thresholding technique was used to map wet areas using RADARSAT-1 SAR data after information from LIDAR-DEMs had been used to correct confusing radar backscatter overlaps between open water and dry, flat, smooth surfaces. Compared to the "status quo", the integrated approach mapped 113% to 600% and 217% to 467% increases in the size of wet areas and pond densities, respectively. Maps based on the ETM-5 band alone detected 133% to 333% and 50% to 350% increases in the size of wet areas and pond densities, respectively over the "status quo" map, while maps based on the RADARSAT-1 SAR data detected 63% to 450% and 100% to 333% increases. The improved mapping capability is attributed to a combinatory power of the integrated approach in detecting small, transient and saturated wet areas. © 2012 Elsevier B.V.


Shaw N.T.,Algoma University
Healthcare Informatics Research | Year: 2012

This paper provides an introduction to Geographical Information Systems (GIS) and how they can be used. It reviews the current state of GIS use in health care before identifying the barriers to more pervasive use of GIS in health. Finally, it makes recommendations for the direction of health GIS research over the next decade and concludes with a call to action to health informatics researchers to stop ignoring a tool and methodology that has such immense potential for improving the health of our communities. © 2012 The Korean Society of Medical Informatics.


News Article | February 21, 2017
Site: phys.org

For years, scientists and policy-makers have been trying to devise strategies to curb this population, which first arrived from Europe through shipping channels in the early 20th century. Now, in a collaborative project with Istvan Imre of Algoma University and Nicholas Johnson of the United States Geological Survey, Concordia biology professor Grant Brown has developed a promising—and natural—solution. Their findings, which focus on the species' own alarm cues, were recently published in Fisheries Management and Ecology. "Lamprey cause estimates of millions of dollars of damage in lost commercial and recreational fisheries," says Brown, whose work in the Faculty of Arts and Science focuses on aquatic behavioural and chemical ecology. "And since they've been introduced into the Great Lakes, they've also caused huge ecological problems." An effective solution is all the more pressing, given the limitations of current approaches. A chemical lampricide, intended to kill the predator at its larval stage without harming other fish, is very labour- and cost-intensive and poses potential harm to the watershed. A slightly more eco-friendly solution is a low-barrier concrete dam that takes advantage of the lamprey's inability to jump upstream. But this also prevents some salmon and trout from getting through, and deters minnows and other swimmers. The researchers have found a substance that could be a successful deterrent. Unfortunately for the sea lamprey, it actually comes from inside the invader itself. Like many fish, upon injury, the lamprey release a compound into the water with a smell that warns others in their species that danger is near. After identifying and confirming these cues under lab conditions, Brown and his colleagues investigated whether they were an effective deterrent in the real-world setting. In an intensive project, they tagged hundreds of sea lamprey with passive transponder tags and then found a testing ground. "By applying these naturally occurring alarm cues to the tributary stream just above the mouth of the main stream, we wanted to determine if we could prevent migrating sea lamprey from going up into that stream. In other words, could we make a chemical barrier to stop the lamprey?" In control tests, over 60 per cent of tagged lamprey swam up the main stream and around 25 per cent went up the tributary stream. But when they employed the alarm cue barrier, fewer lamprey swam upstream (less than 40 per cent) and 2 lamprey (3 per cent of tagged fish) entered the tributary. The group repeated the study with some variations and found the same dramatic difference. Brown notes that the findings are even more exciting when coupled with research by scientists at Michigan State University, who are working on pheromone cues to attract the species. "So we can set up traps in streams, and by using these mating pheromones to attract adults combined with the alarm cues to prevent them from going up tributary streams, we can push them away from areas we don't want them, and pull them into areas where we do." Additional future directions that Brown would like to take with the study include experiments with a synthetic compound, with the goal being to manufacture it on a larger scale. He also wants to look at different stages in the lamprey's cycle, and even test out the successful approach on other invasive species such as the round goby and Asian carp. More information: R. T. Di Rocco et al. Sea lamprey avoid areas scented with conspecific tissue extract in Michigan streams, Fisheries Management and Ecology (2016). DOI: 10.1111/fme.12198


News Article | February 21, 2017
Site: www.eurekalert.org

Montreal, February 21, 2017 -- Of all the fishy predators in the Great Lakes, few are more destructive than the sea lamprey. There's something of a horror movie in their approach: jawless, they attach to prey such as salmon, whitefish or trout with a sucker mouth and drain the victim of its blood and lymph. For years, scientists and policy-makers have been trying to devise strategies to curb this population, which first arrived from Europe through shipping channels in the early 20th century. Now, in a collaborative project with Istvan Imre of Algoma University and Nicholas Johnson of the United States Geological Survey, Concordia biology professor Grant Brown has developed a promising -- and natural -- solution. Their findings, which focus on the species' own alarm cues, were recently published in Fisheries Management and Ecology. "Lamprey cause estimates of millions of dollars of damage in lost commercial and recreational fisheries," says Brown, whose work in the Faculty of Arts and Science focuses on aquatic behavioural and chemical ecology. "And since they've been introduced into the Great Lakes, they've also caused huge ecological problems." An effective solution is all the more pressing, given the limitations of current approaches. A chemical lampricide, intended to kill the predator at its larval stage without harming other fish, is very labour- and cost-intensive and poses potential harm to the watershed. A slightly more eco-friendly solution is a low-barrier concrete dam that takes advantage of the lamprey's inability to jump upstream. But this also prevents some salmon and trout from getting through, and deters minnows and other swimmers. The researchers have found a substance that could be a successful deterrent. Unfortunately for the sea lamprey, it actually comes from inside the invader itself. Like many fish, upon injury, the lamprey release a compound into the water with a smell that warns others in their species that danger is near. After identifying and confirming these cues under lab conditions, Brown and his colleagues investigated whether they were an effective deterrent in the real-world setting. In an intensive project, they tagged hundreds of sea lamprey with passive transponder tags and then found a testing ground. "By applying these naturally occurring alarm cues to the tributary stream just above the mouth of the main stream, we wanted to determine if we could prevent migrating sea lamprey from going up into that stream. In other words, could we make a chemical barrier to stop the lamprey?" In control tests, over 60 per cent of tagged lamprey swam up the main stream and around 25 per cent went up the tributary stream. But when they employed the alarm cue barrier, fewer lamprey swam upstream (less than 40 per cent) and 2 lamprey (3 per cent of tagged fish) entered the tributary. The group repeated the study with some variations and found the same dramatic difference. Brown notes that the findings are even more exciting when coupled with research by scientists at Michigan State University, who are working on pheromone cues to attract the species. "So we can set up traps in streams, and by using these mating pheromones to attract adults combined with the alarm cues to prevent them from going up tributary streams, we can push them away from areas we don't want them, and pull them into areas where we do." Additional future directions that Brown would like to take with the study include experiments with a synthetic compound, with the goal being to manufacture it on a larger scale. He also wants to look at different stages in the lamprey's cycle, and even test out the successful approach on other invasive species such as the round goby and Asian carp. Department of Biology http://www. Faculty of Arts and Science http://www. Grant Brown http://www.

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