Invasive Fish Species Releases Love Potion

Transcription

1 AN INITIATIVE TO MAKE SCIENTIFIC RESEARCH FROM THE UNIVERSITY OF WINDSOR ACCESSBILE TO SECONDARY SCHOOLS Invasive Fish Species Releases Love Potion by Jenny Delaney, Riverside High School Student Gayathri Sreedharan, Graduate Student, University of Windsor Chris Szpak, Riverside High School Science Teacher Based on the original science contribution Behavioural responses of female round gobies (Neogobius melanostomus) to odours of conspecifics 1 by Don B. Gammon 1. Gammon, D.B., W. Li, A.P. Scott, B.S. Zielinski & L.D. Corkum Behavioural responses of female round gobies (Neogobius melanostomus) to odours of conspecifics. Journal of Fish Biology 67:

2 Acknowledgments This document has been made available to high school science teachers for use in their classrooms through the ASPIRE (A Science Partnership in Research and Education) initiative of the Faculty of Science at the University of Windsor. The paper was developed in response to a request from local area high school teachers for scientific research conducted at the University of Windsor to be translated into material that could be easily understood by high school students. This represents the first such effort and is the result of a partnership between Biology graduate student Gayathri Sreedharan under the supervision of Dr. Lynda Corkum and Jenny Delaney a Riverside High School student under the supervision of Riverside HS science teacher Chris Szpak. The original science contribution was a paper authored by Don B. Gammon, a student in Dr. Lynda Corkum s research lab and published in 2005 in the Journal of Fish Biology. A PDF version of the original publication may be obtained by contacting Dr. Corkum at corku@uwindsor.ca. The Great Lakes Fisheries Commission and Dr. Geoff Steinhart (Lake Superior State University) are thanked for their permission to use the photographs appearing in the article. Julie Marentette kindly provided the drawing of the laboratory setup. The contribution and efforts of Dr. Lynda Corkum in the actualization of the final document were substantial and can not go unrecognized. Finally, we thank Don Gammon for his willingness to allow his research publication to be made available to high school science teachers and their students.

3 1 Invasive Species (Ecology/Biodiversity) Exotic fish and other aquatic organisms have been introduced into the Great Lakes and other water bodies of North America for several years. An introduced species is one found outside of its native range. The growth of some of these species such as zebra mussel (Dreissena polymorpha), quagga mussel (Dreissena bugensis) and sea lamprey (Petromyzon marinus), has been explosive. Both invaders have decimated local populations of invertebrates and fish, leading to great economic and ecological impacts. Others invaders include the spiny water flea (Bythotrephes longimanus), a marsh plant called the purple loostrife (Lythrum salicaria) and an aquatic plant, the Eurasian watermilfoil (Myriophyllum spicatum). Many invasive teleost fishes also pose a threat to Great Lakes communities. These fishes include the round goby, (Neogobius melanostomus), Eurasian ruffe, (Gymnophelaus cernuus), goldfish, (Carassius auratus), the common carp, (Cyprinus carpio) and several species of Asian carp [(grass carp, (Ctenopharyngodon idella); silver carp, (Hypophthalmichthys molotrix); bighead carp, (Aristichthys nobilis), and black carp, (Mylopharyngodon piceus)]. More recent invaders are the round and tubenose gobies, both native to the Black and Caspian Seas. The tubenose goby, (Proterorhinus marmoratus), has not spread as successfully and is limited to the St. Clair River, Lake St. Clair, the Detroit River and the Canadian shoreline of western Lake Erie. The round goby, on the other hand, is well established throughout the Great Lakes. The following photographs are of invasive fishes. The photographs were made available with permission from the Great Lakes Fishery Commission (GLFC) unless otherwise indicated. Bighead, black and silver carp, IL and IN Sea Grant Head of silver carp, GLFC Lake trout with sea lamprey, GLFC Parasitic mouth of the sea lamprey, GLFC Sea lamprey, GLFC Eurasian Ruff, GLFC

4 2 Round Goby (Neogobius melanostomus) Round goby, MI Sea Grant Dr. Corkum, her undergraduate and graduate students at the University of Windsor are studying the round goby. The round goby, (Neogobius melanostomus), is a bottomdwelling fish, introduced into the Great Lakes presumably by ballast water of transoceanic vessels. The round goby is a small, soft-bodied fish with a distinct black spot on its dorsal fin and a characteristic fused pelvic fin which it uses as a suctorial disc to anchor itself to the rock or cobble substrate in fast flowing water and to assist in releasing gametes on nest surfaces. Round gobies were initially discovered on the U.S. side of the St. Clair River in April 1990 and were later found in Canadian waters in June They have since spread rapidly through all five Great Lakes and it has been reported that there are about 9.9 billion gobies present in western Lake Erie. There is concern that the round goby will spread from the Great Lakes basin to the Mississippi River basin where they may negatively affect native organisms. Round gobies have also spread into inland waters of Ontario such as Pefferlaw Brook, a tributary that enters Lake Simcoe, a lake with a significant recreational fishery and the Trent River System. Proliferation of this non-indigenous species (NIS) is due to its many features including its broad diet. For example, Dr. Corkum of the University of Windsor found that the round goby feeds mainly on bivalves and amphipods, but also consumes cladocerans, crayfish, dragonflies, isopods, mayflies, fish larvae and fish eggs (Corkum et al., 2004). They are aggressive nest defenders; guarding males typically extend their snouts out of the nest opening and nip at intruders (Wickett and Corkum, 1998). Parental males provide sole care for eggs, fanning to keep them well oxygenated and defending them against predators (Wickett and Corkum, 1998). In addition, most gobiids are iteroparous (i.e. the fish spawn several times each season and in more than one year). The round goby may spawn from three to six times from late April until the end of August (Corkum et al., 1998; MacInnis and Corkum, 2000). The long spawning season of the round goby overlaps with those of native fishes. North America Europe Likely Shipping Route Followed by Transoceanic Vessels Across the Atlantic Ocean Negative Impacts on Native Populations (Ecology) The round goby has had many adverse effects on native populations, including, altering ecological function by changing energy and contaminant pathways and transferring contaminants through the food web (Corkum et al., 2004). The most negative of these effects is the predation on eggs and larvae of native fish leading to a decrease in recruitment and ultimate reduction in population size. Dubs and Corkum (1996) suggested that the aggressive behaviour of round gobies may have forced sculpins to deeper waters where they had fewer spawning sites, less food and were more susceptible to large predators. The extinction of a local population of mottled sculpins in southern Lake Michigan is also believed to be due to recruitment failure, mainly brought about by round goby interference with spawning. It has also been predicted that gobies

5 3 will negatively affect the reproduction and hence, population recovery of lake trout, (Salvelinus namaycush). Round gobies also feed on benthic invertebrates such as zebra mussels which are exposed to contaminated sediments. When gobies are in turn consumed by piscivores such as burbot, (Lota lota) and yellow perch, (Perca flavescens), the fish diet of humans is a health concern (Corkum et al., 2004). In the Bass Islands in Lake Erie, video footage has shown that removal of nest-guarding smallmouth bass, (Micropterus dolomieu), results in the predation of embryos by round gobies. These eggs were not consumed for the most part in the presence of the parental male, but in its absence and while it recovered from angling stress, gobies consumed unhatched eggs (Steinhart et al. 2004). A round goby consumes 1,000 unhatched embryos and 400 hatched embryos during the average time (about 5 min) a smallmouth bass was away from the nest (Steinhart et al. 2004). Hence, goby predation coupled with catch-and-release angling has reduced survival of smallmouth bass embryos. Chemical Communication in the Round Goby (Nervous/Endocrine System) The chemosensory system in fish allows them to sense and respond to a local concentration change of a particular chemical compound. This helps influence important behaviours such as food-finding, recognition/location of familiar habitat, predator avoidance, and intraspecific communication. These systems can detect chemical cues, which are found everywhere in the aquatic environment, as odours are released in large quantities from aquatic organisms through the gills, urine and faeces. These chemicals are then allowed to dissolve and disperse in water making them available as biologically relevant cues detected by receptor systems found in aquatic organisms, usually resulting in five chemosensory behaviours: feeding, detecting danger, nonsexual social interaction, orientation and reproductive synchrony. Timing of reproduction usually occurs when sexually mature fish release specific chemical cues that 'signal' their condition to conspecifics. Conspecifics are individuals belonging to the same species. For example, round gobies are an aggregating species where many males occupy nests in the same area. Hence, males set up nests beside conspecifics. The chemicals, pheromones, are defined as an odour or mixture of odorants released by an individual the sender and evoking in conspecifics (the receivers) adaptive, specific, and species-typical response(s), the expression of which need not require prior experience or learning. Pheromones play an important role in various modes of communication such as recognition of one's own species, assessing an individual's relative dominant or submissive attitude, maintaining cohesion in a school, warning conspecifics of predators and for parentyoung interactions. A handful of these pheromones are chemically identified and all are remarkably potent. These pheromones are used naturally by organisms as reproductive attractants and behavioural stimulants, initiating the coordinated release of various hormones and steroids leading to successful reproduction and proliferation of the species. These characteristics make them ideal to use when trying to reduce numbers of invasive exotic species that have invaded the Great Lakes and are adversely affecting native fish populations. They may be used in the control of fish species such as the round goby, (Neogobius melanostomus) and sea lamprey, (Petromyzon marinus) which have reproduced successfully and colonized all the Great lakes (Corkum, 2004). In the round goby, males provide sole parental care, maintaining and defending eggs without feeding. Females arrive at the nests later and up to fifteen females may lay eggs in a single nest (MacInnis and Corkum, 2000). Since males usually occupy nests on complex substrates with low visibility, communication between the males and females likely occurs through chemoreception. Sex pheromones are released by males and detected by females which respond by searching for and arriving at the nests.

6 Nest-guarding parental male smallmouth bass guarding young. Photos are courtesy of Dr. Geoffrey Steinhart, Lake Superior State University. 4 When the parental smallmouth bass is removed by anglers, neighbouring round gobies move in and feed on its young A study by Don Gammon at the University of Windsor (2004) was the first to use washings or male conditioned water (MCW) from reproductive males (RM) and measure the response of both reproductive (RF) and non-reproductive (NRF) females. Below is a detailed explanation of the procedures followed by researchers at the University of Windsor (Gammon et al., 2005) in conducting this experiment. The goal of this study was to investigate the behavioural response of female round gobies when exposed to various chemical cues from conspecifics. The response of both RF and NRF exposed to odours from 5 treatments:

7 5 conditioned water from RM, non-reproductive males (NRM), RF, non-reproductive females (NRF) and control (dechlorinated) water was measured. Male and female washings instead of steroidal compounds were used to ensure that no essential component of the pheromone blend was missing. Don Gammon predicted that RF would have a more pronounced response to water from RM than NRF. Experimental Design A Flow-through Trough Round gobies were captured by angling from the Canadian waters of the Detroit River and by trawling in the western basin of Lake Erie. All fish were stored in holding tanks at 18 C to mirror temperatures in the field and under constant photoperiod in the animal quarters facility of the University of Windsor (Department of Biological Sciences). All round gobies were fed daily with Nutrafin fish flakes. After 24 h, fish were separated into 4 categories (RM, NRM, RF and NRF) based on sex and reproductive status. Males and females were sexed by examining the urogenital papilla which is pointed in males and oval in females. RM were identified by their black nuptial colouration, enlarged cheeks and thickness of their papilla. RF were identified by their swollen abdomens. The reproductive status for both males and females was confirmed by determining their gonadosomatic index (GSI = Gonad weight/body weight x 100). Conditioned water from males and females were obtained by placing a single fish in 1 L of dechlorinated aerated tapwater for 4 h. Gonadosomatic Index (%) Used to determine Reproductive Status of Males and Females RM 1.3 NRM <1.3 RF 8 NRF < 8 Lab Study Laboratory experiments were conducted to determine if RF respond to control water or odours from RM, NRM, RF or NRF. Each behavioural fish was only used once. During each trial, a RF or NRF was placed in a shelter (0.16 m long x 0.11 m wide x 0.05 m high) at one end of the tank (0.88 m long x 0.28 m wide 0.28 m high) with 20 L of 18 C aerated dechlorinated water. Every shelter had a single opening facing the opposite end of the tank. The back of the shelter had a series of small holes that allowed water to flow through the shelter preventing build up of odour. An air stone was placed at the front end of the tank where odour water would be introduced in order to circulate odour quickly and evenly throughout the tank.

8 6 Behavioural fish introduced here Stimulus or control water introduced here Each trial was 1h and 15 min and had three sequential periods: acclimation, control and stimulus. The acclimation period, during which no water was added was 30 min long, the control period during which dechlorinated aerated water was added was 15 min long and the stimulus period during which either conditioned water or control water was added was 30 min long. Only the last 15 min of the acclimation period and the first 15 min of the stimulus period were used in analysis. These time periods enabled the trials to begin and end without disturbing the fish as previous observations have shown that the presence of an observer can significantly change round goby ventilation rates. The control period was used to verify that movement of fish during the stimulus period was in response to odours in the water, not due to the addition of fluid into the tank. Fish response to dechlorinated tapwater in the control and stimulus periods was examined to determine of there were any possible changes in fish behaviour over time. During the stimulus period of each trial, conditioned water or control water was introduced through an intravenous bag (600 ml) secured above the experimental tank, attached to Tygon delivery tubing. Flow from the valve was regulated at 6 ml/min by a valve and outflow was removed from the opposite end of the tank so that total volume of water remained constant throughout the tank. Preliminary trials showed that an air stone placed at the front end of the flume near the odour source distributed dye evenly throughout the tank. Tubing and tanks were flushed with dechlorinated water between experiments. Experimental Apparatus for Behavioural Trials (Diagram prepared by Julie Marentette)

9 7 Behavioural Analysis Fish response to treatments was videotaped using a colour camera mounted overhead. Videotapes were analyzed using a 2-D image analysis system to measure three dependent variables: 1) time spent in the far half of the tank near the odour source, 2) mean swimming velocity of the female, 3) pathway of movement by the female Results Time spent near the odour source Analysis of data showed that there were significant differences between stimulus and control periods among the five treatments for the time that females spent in the far half of the tank near the odour source for both RF and NRF. Further analysis showed that RF spent more time in the far half of the tank when exposed to odours from RM than control water. There was however, no statistically significant difference in the time that RF spent near the odour sources for the remaining four treatments (NRM, RF, NRF and control). On the other hand, NRF spent significantly more time in the far half of the tank when exposed to RF conditioned water compared to control water. Time Spent Near the Odour Source by Reproductive Females Mean Time Spent (s) Control Stimulus 0 RM 1 NRF 2 RM 3 NRM 4 Control5 Odour Time Spent Near the odour Source by Non- Reproductive Females Mean Time Spent (s) Control Stimulus 0 RM RM 1 NRM NRM 2 RF NRF 3 Control NRF 4 Control 5 Odour

10 8 Velocity of Fish Movement Data analysis showed there were significant differences in swimming velocity of RF between stimulus and control periods among the five treatments. Results showed RF swam faster during the stimulus period (exposed to RM water) than the control period. On the other hand, NRF exhibited no differences in swimming velocities between the control and stimulus periods among treatments. Mean Swimming Velocity of Reproductive Females 12 Mean Swmming Velocity (cm/s) RM 1 NRM NRM 2 RF RF NRF 3 NRF Control 4 Control 5 Odour Control Stimulus Mean Swimming Velocity of Non-Reproductive Females 7 Mean Swimming Velocity (cm/s) RM 1 RM NRM 2 RF 3 NRM NRF 4 Control 5 RF NRF Control Odour Control Stimulus

11 9 Direction of Movement Although no quantitative comparisons were performed for swimming pathway of RF, pathways were clearly different between control and stimulus periods when the treatment odour was that of RM. During the control period, RF usually swam near the shelter with occasional movement to the opposite end of the tank. When exposed to RM water, RF exhibited a dramatically different swimming pathway. They swam directly from the shelter to the odour source at the opposite end of the tank, followed by a rapid back and forth-movement parallel to and along the width of the tank where the RM-conditioned water was added. The pathways of NRF were different only when the stimulus odour was that of RF. Similar to RF, NRF stayed near the shelter during the control period but exhibited directed movement to the opposite end of the tank within minutes of the odour being added. Back and forth-movement displayed by RF along the far wall of the tank was also exhibited by NRF. Overview of Position of Fish, Odour Source and Direction of Flow Direction of flow Behavioural fish placed inside shelter at this end Stimulus and control water added at this end Swimming Pathway of Reproductive Female in Response to Control Water Tank width Control Tank length Tank width Swimming Pathway of Reproductive Female in Response to Reproductive Male Water RM water Tank length Swimming Pathway of Non-Reproductive Female in Response to Control Water

12 10 Tank width Control water Tank width Tank length length Swimming Pathway of Non-Reproductive Female Tank length RF Water Discussion This study demonstrates that RM round gobies release chemical cues which initiate behavioural responses in RF with observable changes in time spent near the odour source, swimming velocities and swimming pathways. NRF spent more time near the odour source when exposed to RF odour compared to a control. These results suggest that the round goby uses both inter- and intra-sexual pheromonal communication. These findings were however, supported by physiological assays, where electro-olfactogram (EOG) studies showed that RM water was a potent olfactory stimulus to RF, but not to NRF (Belanger et al., 2004). In addition, NRF also exhibited elevated EOG values when exposed to RF conditioned water but not to water from NRF, RM and NRM. Sex and reproductive status are also important in other fish species such as fathead minnows and African catfish exhibiting chemical communication. The attraction of RF to RM water suggests that male sex pheromones rather than visual cues are used by females to find nesting sites, which are often located in dark areas (Wickett and Corkum, 1998). Pheromone-based mate attraction is important in ovulating female sea lamprey (Petromyzon marinus), in which females can improve their chances of reaching nesting sites upstream by responding to male-based chemical stimuli through active swimming against currents and searching behaviour. Round goby males that attract RF increase their chances of mating and the females benefit because their eggs have been deposited in nests guarded by parental males. Intra-sexual as well as inter-sexual pheromones have been studied in several species of fishes. However, the present study is the first to demonstrate pheromone-based attraction of females to other females in the Gobiidae. This female intra-sexual attraction may be linked to the development of aggregations of conspecifics as proposed in other species. For example, female zebrafish (Danio rerio) are known to attract other females and this may be associated with shoaling behaviour. Female guppies (Poecilia reticulata) have also shown preference for water containing the odour of sexually mature females over that of odourless water and this attraction is also thought to be involved in shoaling. Although round gobies are a non-shoaling species, they are often found in large aggregations in their benthic environments. Hence, this attraction between females may function in facilitating aggregations of round gobies. Studies have shown that female bluehead wrasse (Thalassoma bifasciatum) follow other females to learn the routes of mating sites. During reproductive season, males are the first to leave deeper waters and move inshore where they establish nests and are later followed by females. Odour plumes from colonial nesting males may guide RF to nests and NRF may play follow the leader, tracking them. Although many researchers have measured dependent variables such as time spent near the odour, turning movements or ventilation changes to examine response of individuals to conspecific odours, swimming velocity is seldom used. The increased swimming velocity of RF exposed to RM odours is important because fishes that are negatively buoyant and slow swimmers, such as the round goby, may incur high energy losses trying to stabilize their swimming trajectories. The analysis of RF swimming pathways not only helped determine the

13 11 type of response but also gives indications of how the animal detects it. Although quantitative analysis of the locomotor behaviour of round gobies is beyond the scope of this paper, several clues indicate that they may use chemotropotaxis, directed turns based on simultaneous comparison of the intensity of a chemical stimulus on either side of the body. Females responding to RM and RF odour exhibited back and forth-movements, keeping their bodies perpendicular to the wall of the tank, near the odour source. A study on the locomotor responses of male channel catfish (Ictalurus punctatus) to female pheromones suggested that the males may be using chemotropotaxis to locate the source of the odour. Round gobies may have the ability to actively sniff their surroundings by maintaining constant flow of water over their olfactory epithelium through the pumping mechanism of accessory nasal sacs. Ultimate Goal The ultimate goal of these studies is to gather background information to develop pheromone traps to capture RF where they co-occur with native fish populations on spawning grounds where round gobies prey on the eggs of native species. This management tool will have many advantages: 1) fish response to sex pheromones is largely instinctual and hence can be expected from a large number of adults; 2) very small amounts of the pheromone odour will be needed in the environment for the desired response; 3) these pheromones are unlikely to have any negative effects on the environment at these low concentrations; and, 4) this method of pheromone trapping can be used to control other invasive species since sex pheromones are used by a wide variety of species. Questions 1. Why is it necessary to hold experimental fish at a temperature of 18 C? 2. Why were small holes drilled into the back of the shelter? 3. What was the importance of the acclimation period (no water is added) and the control period (dechlorinated water was added)? 4. Graph 1 shows the RF response to the five treatments. In which of the treatments did RF show a pronounced response? Does this provide evidence to support the hypothesis we are trying to test? 5. To which of the treatments did NRF show a more pronounced response? What benefits would this behaviour provide for NRF. 6. Graph 3 and 4 show similar responses of RF and NRF in terms of swimming velocity. In the field, what behaviour would swimming velocity represent? 7. Name the dependent and independent variables? 8. This study has shown that RF detect and respond to odours from RM. If a study was conducted to test whether RM respond to RF odours, would you expect to see a RM response to RF odours, if yes, why would this be important? 9. What was the purpose of adding a control treatment when each trial has its own control period? 10. If a successful management tool was developed to capture and remove RF, what would be the advantage of targeting RF instead of RM? References Arbuckle, W.J., A.J. Belanger, L.D. Corkum, B.S. Zielinski, W. Li, S-S. Yun, S. Bachynski & A.P. Scott In vitro biosynthesis of novel 5B-reduced steroids by the testis of the round goby, Neogobius melanostomus. General and Comparative Endocrinology 140:1-13. Belanger, A.J., W.J. Arbuckle, L.D. Corkum, D.B. Gammon, W. Li, A.P. Scott & B.S. Zielinski Behavioural and electrophysiological responses by reproductive female Neogobius melanostomus to odours released by conspecific males. Journal of Fish Biology 65: Corkum, L.D Pheromone signalling in conservation. Aquatic Conservation: Marine and Freshwater Ecosystems 14: Dubs, D. & L.D. Corkum Behavioural interactions between round gobies (Neogobius melanostomus) and mottled sculpins (Cottus bairdi). J. Great Lakes Res. 22:

14 12 MacInnis, A. J Fecundity and reproductive season of the round goby Neogobius melanostomus in the Upper Detroit River. Transactions of the American Fisheries Society 129: Steinhart, G.B., E.A. Marschall & R.A. Stein Round goby predation on smallmouth bass offspring in nests during simulated catch-and-release angling. Transactions of the American Fisheries Society 133: Wickett, R.G. & L.D. Corkum Nest defense by the exotic fish, round goby, Neogobius melanostomus (Gobiidae), on a shipwreck in western Lake Erie. Canadian Field-Naturalist 122: Appendix Reproductive Male Round Goby (Neogobius melanostomus). This nest-holding male is black with puffy cheeks. Photo by Lynda Corkum. Tubenose Goby (Proterorhinus marmoratus). Note the long nostrils. Photo by Lynda Corkum. Ventral view of a tubenose goby. The fused pelvic fin (arrow) is characteristic of all species within the taxonomic family Gobiidae. Photo by Lynda Corkum.

15 13 About the Authors Jennifer Delaney Jennifer Louise Delaney, attended elementary school at M.S. Hetherington, and is currently a student at Riverside Secondary School. She loves Biological Sciences, and Psychology, especially topics on the brain and behaviour. Jennifer plans to attend the University of Windsor and would like to obtain an Honours degree in Arts and Science with a major in Biology and minor in Psychology. Ultimately, Jennifer would like to enter the Optometry program at the University of Waterloo. Don Gammon Although Don Gammon was born in Oakville, Ontario, his schooling began in Tecumseh, where he attended A.V. Graham Elementary School and Belle River District High School. Having found an interest in biology during high school, Don pursued a Bachelor of Sciences degree at the University of Windsor. In his second year at university he attended ecology courses taught by Dr. Lynda Corkum. During this course work, he became interested in how animals interact with each other and their environment, and soon began his research career when he obtained a summer research position in Dr. Corkum s laboratory. Don studied in Dr. Corkum s laboratory for the next two years. His undergraduate thesis research at the University of Windsor led to the work presented here. In 2004, Don graduated from the University of Windsor and moved to the University of Alberta where he is pursuing his PhD in a new research interest, medical virology. Gayathri Sreedharan Gayathri Sreedharan is a Master s student working in Lynda Corkum s laboratory at the University of Windsor. Before moving to New Brunswick in 2000, Gayathri completed her schooling in the United Arab Emirates, where she developed an interest in Biology. At University of New Brunswick, Gayathri became interested in the behavioural ecology of fishes. She joined Lynda s lab in Gayathri s research examines round goby response to food odours, which is part of a larger project, focusing on a pheromone trapping system to capture this invasive species. Chris Szpak Chris Szpak graduated from Sandwich Secondary School. He received an Honours B.Sc. in ecology from the University of Windsor and a B.Ed. from the University of Calgary. He began his teaching career in Alberta in He taught grades 7 to 12 teaching general science, biology, chemistry, physics and math. He was involved in Alberta Provincial Exam item writing, exam evaluation and marking for biology and grade 9 science. He began teaching for the Greater Essex county District School Board in He has taught general science, biology and math at W.D. Lowe and Riverside Secondary Schools. He is currently a vice-principal at Vincent Massey Secondary School.