The Invasion of the Asian Carp 5/04/2010 Jerome Barner, Jesse Zastrow, Zachary Fournier, Eamon Harrity

Transcription

1 The Invasion of the Asian Carp 5/04/2010 Jerome Barner, Jesse Zastrow, Zachary Fournier, Eamon Harrity I. EXECUTIVE SUMMARY Silver carp (Hypophthalmicthys molitrix) and bigheaded carp (Hypophthalmicthys nobilis) are invasive plantivorous fish that have serious ecological, economic, and social impacts in the Mississippi and Missouri River Systems. The carp escaped from aquaculture ponds of Arkansas, where they were introduced to control plankton populations nearly 40 years ago, and have since rapidly expanded their range throughout the Midwest up the Mississippi River all the way to the banks of Lake Michigan. These fish (hereafter referred to as Asian carp) are natives of Eastern China and are extremely voracious planktivores. Known to eat all types of plankton, they disrupt the natural food web of aquatic systems wherever they go. Now that Asian carp have been sighted within miles of Lake Michigan, people are growing concerned. Many believe that they have the potential to invade the Great Lakes and cause extensive ecological, economic, as well as social damages; however, some argue that the lakes are not suitable habitat and will likely not be fully colonized by Asian carp. This report explores the susceptibility of the Great Lakes and Lake Champlain to the invasion of the Asian carp, taking into consideration life history and characteristics of the carp, environmental conditions of the lakes, and potential pathways of introduction. We conclude that, though not ideal for the carp, the Great Lakes and Lake Champlain would provide suitable conditions for population establishment. Should this happen, we believe that the ecological, economic, and social impacts will be severe. Accordingly, we explore the cost, effectiveness, and implementation of several existing and proposed preventative measures to keep Asian carp out of the Great Lakes and ultimately Lake Champlain. 1

2 Table of contents I. Executive Summary.. 1 II. Problem Statement III. Background... 3 IV. Purpose Statement... 3 V. Objectives. 4 VI. Approach... 4 VII. Findings The Carp Distribution Habitat Biological Requirements Behavior The Lakes Characteristics Pathways and Connections Canals Human Facilitated Introduction a. Ballast Waters b. Escape and Release Pathways and Connections between the Lakes a. Canals b. Human Facilitated Introduction Asian carp Preventative Measures Current Asian carp Preventative Measures a. CSSC Underwater Electrical Barrier b. edna Sampling c. Rapid Response Program d. Electro-fishing/Netting/Targeted Removal Alternative Asian carp Preventative Measures a. Physical Barriers b. Bubble Curtains c. Acoustic Deterrents.. 21 i. Sound Projector Array. 21 ii. Bio-acoustic Fish Fence.. 21 iii. Hybrid Systems d. Strobe Lights e. Modified Structural Operations 22 i. Modified Lock Operations 22 ii. Modified Bank Fortifications f. Chemical, Biological, Social Controls 22 i. Chemical Controls 22 ii. Biological Controls.. 23 iii. Social Controls 23 VIII. Conclusions and Recommendations Perceived Impacts Ecological Impacts of the carp Economic Impacts of the carp Recommendations. 24 IX. Acknowledgements X. Literature Cited 25 2

3 II. PROBLEM STATEMENT The spread of the silver and bighead carp poses a threat to many North American waterways and could have significant social, economic, and ecological impacts on the Great Lakes and Lake Champlain Basin. III. BACKGROUND The silver carp, Hypophthalmichthys molitrix, and bighead carp, Hypophthalmichthys nobilis (hereafter referred to as Asian carp) are filter feeders that consume zooplankton, phytoplankton, and other particulate matter (Cooke et al. 2009). They are very prolific fish that grow and mature quickly. They were first introduced to the United States for the use of cleaning southern fish farms in the late 1970 s and have since spread throughout the Mississippi River System all the way up to the Chicago Sanitary and Shipping Canal, a mere 7-70 miles from Lake Michigan (Asian Carp Work Group 2010). These hungry consumers can live up to 20 years and have been known to migrate 14 km/day, making it seem probable that they will soon enter Lake Michigan (Cooke et. al 2009). Once in the lake, it is likely that they will disrupt food sources for the native larva and adult fishes because,they feed on the plankton that form the bottom of the pelagic food web at an incredibly high rate (Hill 2008). The economy in this area could be greatly affected by the invasion of the Asian carp. The reduction of game fish would have a severe economic impact on the $7 billion sport fish industry of the Great Lakes (Hill 2008). In the Mississippi their effects on the fisheries have already been documented; many have shut down due to the disappearance of the native fish and ironically the overloading of carp. In some cases, the fishermen are simply not able to lift their nets out of the water due the weight of the carp. Lake Champlain may not be too far removed from this problem. A number of pathways connect the Great Lakes and Lake Champlain, including the Champlain Canal that runs between the Erie Canal and the southern end of the lake (Malchoff 2005). It is believed that invasive species such as the sea lamprey and zebra mussels have entered Lake Champlain via this route (Malchoff 2005). It is possible that once established in the Great Lakes, the Asian carp could also follow this pathway to Lake Champlain. It remains to be seen if the Asian carp will be able to survive in the mesotrophic environment of the lakes. They will certainly be able to survive in the wetlands, productive bays, and inlets where plankton counts are high, but their migration across the lakes may be hindered by the low numbers of plankton densities (Hill 2008 and Modley 2010). If this is the case, it may not be necessary to invest millions of dollars preventing the spread of the Asian carp as it will occur naturally. However, the potential impacts of their establishment coupled with the fact that many of the Great Lakes are facing eutrophication problems, make this too risky to leave to chance. IV. PURPOSE STATEMENT To evaluate the susceptibility of the Great Lakes and Lake Champlain to the silver and bighead carp invasion, examine perceived impacts and explore preventative measures. 3

4 V. OBJECTIVES Describe the ecological niche, origin, mode of introduction and current distribution in North America of the silver and bighead carp. Research and evaluate the ecological conditions of Lake Michigan, Lake Erie, and Lake Champlain. Identify and evaluate the potential pathways for the spread of the Asian carp. Explore the implementation and effectiveness of preventative measures (both already in place and hypothetical) to control the spread of the Asian carp. Theorize what the ecological, economical, and social impacts of the Asian carp would be. VI. APPROACH We took advantage of the library.uvm.edu website to search for relevant journal titles including Hydrobiologia, Journal of Great Lakes Research and Environmental Management. We utilized Academic Search Premier and Google.Scholar to locate pertinent journal articles and other online resources. Key words for our searches included but were not limited to ecological niche, bighead and silver carp, plankton FCUs, Lake Champlain invasive species, exposure pathways, aquatic nuisance species, preventative measures, electroshock barriers, Chicago Shipping and Sanitary Canal, New York Canal System, Champlain Canal, implications of Asian carp invasion, Mississippi River System, water quality, threat to sport fishing industry, Great Lakes integrity, and Asian carp respirometry. Another useful technique for locating useful resources involved scanning the reference sections of helpful articles for related topics. We contacted the State of the Lake and the Nature Conservancy of Vermont but were unable to meet with them. We were hoping to get an idea of the local experts opinions on the potential of the Asian carp spread, impacts, and likelihood of success in the Lake systems. We spoke with Ellen Marsden, a fish expert at the University of Vermont about the most likelihood of the Asian carp s spread to Lake Champlain as well as the most practical preventative measures. We spoke with Meg Modley, the Aquatic Nuisance Species Coordinator for the Lake Champlain Basin Program about the threat posed by the spreading Asian carp. We also spoke with Rebecca Gorney, a graduate student working with plankton and invasive fish here in Lake Champlain, about the potential impacts of the carp on the lake. VII. FINDINGS Here we present our findings. They include a discussion of the Asian carp, an evaluation of the current status of three lakes of concern, Lake Michigan, Lake Erie, and Lake Champlain, a look at potential vectors and pathways, and finally an in-depth analysis of preventative measures. 1. The Carp Silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis) 1.1 Distribution Silver carp (figure 1), Hypophthalmichthys molitrix, and bighead carp (figure 2), Hypophthalmichthys nobilis originate from large river and floodplain lake systems of Eastern Asia, particularly eastern China, southern Russia and northern North Korea (Kolaret. al. 2005). They have been transported throughout the world for their exceptional ability to filter 4

5 feed and control excessive phytoplankton levels (Lieberman, 1994). Unlike Common Carp which were imported from Europe to the US in 1831 and grass carp from Asia in 1963, Silver and Bighead were introduced from China in 1973 (Koel et al., 2000). These two carp were brought in to clean up aquaculture ponds primarily in Arkansas and were first documented in the Upper Mississippi River System in 1982 (Koel et al., 2000). Figure 1: Native range of bighead carp, mainly large rivers and lakes of southeastern Asia; eastern China, eastern Siberia, and the extreme northern range of North Korea (Kolar et al. 2005) Figure 2: Native range of silver carp, mainly large rivers and lakes of eastern China and eastern Russia that run into the Pacific Ocean (Kolar et al. 2005) In North America, the silver carp have been recorded in 12 states and the bighead in at least 18. They have spread through every major tributary of the Mississippi and Missouri Rivers, and are broadly established in the Upper Mississippi River System (figures 3 &4). The carp have made it to within 7 miles of Lake Michigan via the Chicago Sanitary and Shipping Canal. Figure 3: Range of silver carp in the US, as of August 2009 (Fuller, 2009) Figure 4: Range of bighead carp in the US, as of August, 2009 ( 1 Fuller, 2009) 5

6 1.2 Habitat The Asian carp prefer slow-moving water at depths greater than 3 meters and usually reside in large rivers, ponds, lakes, reservoirs and large canals. However, the fish typically require a suitable riverine habitat for spawning and recruitment. Their life history involves moving downstream to fast-moving river reaches as adults in the spring to spawn, then return to lake or floodplain reaches (Kolar Chapman et al. 2005). Asian carp spend time in habitats with wing and spur dikes as well as tributary streams, which provide the low-velocity, tranquil waters while maintaining depths greater than 3 meters. Reaches in the Mississippi River Basin supports these habitats and can therefore contribute to the colonization throughout its upper reaches (Williamson 2005). 1.3 Biological Requirements Asian carp are exceptionally adaptable, which explains why they are such effective invasive species. One aspect of their environmental adaptability is their tolerance of water temperature; they have been documented as living in lakes that are frozen 4-6 months of the year, to as warm as about 40 C (Kolar et al. 2005). However, there are relatively narrow optimal ranges at which the carp eat and spawn. Bighead carp react best to temperatures of 25 to 26.9 C (Jennings 1998), whereas silver carp have been reported to do best at a range of C (Kolar et al. 2005). The implications of this are important, as typical summer surfaces temperatures in the Great Lakes can range from 15 to 22 C (Cooke, S.L. et al. 2009), which is below the optimal feeding level for these carp. Asian carp are ravenous consumers, eating from % their body weight in food for bighead to as much as 20% for silver carp per day (Kolar et al. 2005). Carp seem to have food preferences, but can easily switch prey if their primary food source lacks, therefore introducing intense competition for food with other planktivores (Williamson 2005). Bighead carp have an affinity for larger zooplankton, Daphnia magna in particular according to a study conducted by Cooke et al. (2009). Silver carp will primarily feed on larger phytoplankton; however both are extremely opportunistic if necessary, as outlined in Table 1. In the Mississippi River System the carp have out-competed the native fish such as the bigmouth buffalo, gizzard shad, and paddlefish for the phytoplankton and zooplankton communities (Wanner and Klumb 2009). Asian carp grow remarkably quickly and to a large body size; reaching weights typically around 20 kg and around 900mm in length. Bighead carp are thought to average around an 8 year life span while silver carp have been known to live up to 20 years (Kolar et al., 2005). 6

7 Table 1: Compared feeding habits of bighead (Hypophthalmichthys nobilis) and silver (H. molitrix) carps (Kolar et al, 2005). As adaptable, voracious eaters with similar feeding characteristics, among others, they have the potential to drastically change the plankton profile of inhabited waters. Bighead carp Silver carp Type of feeder Primarily a zooplanktivore, but highly opportunistic. Primarily a phytoplanktivore, but highly opportunistic. Food items consumed Zooplankton; phytoplankton; Phytoplankton; zooplankton; bacteria detritus. Will bite on dough (planktonic and in aggregations); balls used as bait. detritus. Can filter smaller particles than bighead carp. Will bite on bread paste and dough balls used as bait. Morphological characteristics specific to Long, comb-like gill rakers coated with mucus to help trap Special filtering apparatus on gill bars allows removal of small particles. feeding smaller particles. Many taste Suprabranchial organ consolidates buds on filtering organ aid detection of zooplankton. ingested materials by producing large amounts of mucus. Consumption rate High; voracious feeder High, but widely variable Feeding temperatures Most active at C. Will continue levels of feeding at 10 C or as low as 2.5 C. Most active at C. Will continue feeding as low as 4 C. More coldtolerant than bighead carp. Ecological niche for feeding Dietary overlap with indigenous species? Often at the water surface, but also feed throughout water column, including bottom. Yes Do not commonly feed at the surface. Yes 1.4 Behavior The behavior of Asian carp has proven to be surprisingly dangerous for boaters and water-skiers in the Mississippi and Missouri River Basin. Asian carp, more noticeably the silver carp, are known to jump from the water in schools when disturbed by boats in the area, particularly those with outboard motors (Kolar et. al. 2005). It is now commonplace to see these fish jump into boats, damage windshields, and injure drivers and passengers of motorized boats along the rivers these fish inhabit (Perea 2002). Eric Gittinger, a fishery biologist working with Asian carp interviewed in an article by P.J. Perea (2002), had been hit by the carp 12 times in two years, with one hit resulting in serious neck injury. In the article, Gittinger claims they can jump up to 10 feet high and 20 feet horizontally (Perea 2002). Image 1 below shows an example of silver carp leaping out of the water from being agitated by a motor boat. Although there is little evidence as to the biological causes of the unusual behavior, it has been cited that the Asian carp jump as a method of avoiding predation (Kolar et. al. 2005). With frequent use by boaters of all varieties on reaches throughout the Mississippi River Basin, the jumping carp pose a serious health risk to those traveling with motorized boats in waters inhabited with the carp. 7

8 Image 1: Jumping Silver Carp, Hypophthalmichthys molitrix. Photograph courtesy of R.D. Nelson, U.S. Department of Agriculture, Natural Resources Conservation Service, Lincoln, Nebraska (Kolar et. al. 2005) 2. The Lakes The ecological status and eutrophic conditions of the Great Lakes and the Lake Champlain region are a determining factor on the distribution of the Asian carp. The Great Lakes ecosystem is the largest freshwater ecosystem in the world with an extensive watershed encompassing 288,000 square miles consisting of 5,000 tributaries and 9,000 miles of shoreline. This region is continuing to be degraded due to an increase in human uses and an influx of invasive aquatic algae, invertebrates, fish and macrophytes that have devastated the native populations. According to Aquatic Nuisance Species Coordinator for the Lake Champlain Basin Program, Meg Modley, there are more than 180 invasive species currently inhabiting the Lakes, (2010). Asian carp pose another potential stressor to these already fragile ecosystems. It is still unclear if the Asian carp have the ability to grow and survive with the lower plankton densities of the open water regions of the Great Lakes basin. Cooke, et al. suggests that the threat of the planktivorous carp will be limited to certain littoral zones, bays, harbors, and back water regions that are likely to have higher plankton levels than pelagic zones, (2009). These areas may provide suitable habitat for dispersal of Asian carp further into the Great Lakes system. 8

9 2.1 Characteristics of Each Lake of Concern Table 2: Comparison of the lake characteristics of each of the three lakes of concern, which are Lake Champlain, Lake Michigan, and Lake Erie to assess the potential establishment of the Asian carp. Lake Characteristics Lake Champlain Lake Michigan Lake Erie Drainage Area 8,234 sq. miles 45,000 sq. miles 30,140 sq. miles Surface Area 435 sq. miles 22,300 sq. miles 9,910 sq. miles Average Width 12 miles 118 miles 57 miles Length 120 miles 307 miles 241 miles Average Depth 64 feet 279 feet 62 feet Table 2 describes the characteristics of the three lakes that the Asian carp may invade. Lake Michigan and Lake Erie have similar drainage areas and lengths. The northern region of the Lake Michigan basin is covered with forests, sparsely populated, and economically dependent on natural resources and tourism. The southern portion of the lake is heavily populated with intensive development and rich agricultural areas along the 1,660 miles of shoreline, (Manninen, 2007). The southern lake is experiencing most of the urbanization within the Lake Michigan Basin. Lake Michigan is the only Great Lake that is within the United States border. The lake serves an array of resources for large commercial and sport fishing industries, a source of drinking water, and water for agricultural irrigation. It also provides transportation routes for fleets of cargo vessels, cooling water for industrial processes, and also a sink for municipal and industrial waste. ( 2006) Lake Erie is the southernmost, shallowest, warmest, and most biologically productive of the five Great Lakes. These are part of the reason it is the largest Great Lakes sport fishery, (Ohio Geological Survey, 2009). The 856 miles of shoreline and the surrounding basin of Lake Erie have been heavily utilized for manufacturing, transportation, industrial development and agricultural uses. These land use practices along with the physical characteristics explained above have created a nutrient rich environment in Lake Erie. Although the lake is the most biologically productive of the five Great Lakes it is considered to be the best walleye fishery in the world. Lake Champlain is the largest lake in New England. The 587 miles of shoreline are divided between Vermont, New York and Quebec, Canada. The lake boosts the local economies with the 50 public boat launches, thriving sport fishing industry, and the extensive state parks and public beaches. Lake Champlain is used for both public cruise lines and private recreational boating. Some of the bays within Lake Champlain have experienced nuisance algal blooms directly related to the nutrient overloading from the shoreline development and the agricultural runoff. The high nutrients and shallow littoral waters have caused areas of the lake to become mesotrophic. Figure 5 shows the eutrophication differences between Lake Michigan and Lake Erie. Although Lake Champlain does not compare to any features of the Great Lakes it is as deep as Lake Erie, which describes the eutrophic status of each lake. 9

10 Figure 5 Scatter plots of Milbrink s modified Environmental Index of the eutrophic conditions of the three regions of Lake Michigan and Lake Erie. Values ranging from indicate oligotrophic conditions; values from indicate mesotrophic conditions (shaded area); values above 1.0 indicate eutrophic conditions. Data points represent average of triplicate samples taken at each sampling site. (U.S. Environmental Protection Agency, 2006) The eutrophic conditions of the lakes illustrate the possible invasion of carp. Based on the impacts they have induced on the relatively eutrophic Mississippi River it is reasonable to suggest that they will have the ability to colonize the bays, backwaters and harbors of Lake Michigan and potentially invade most of Lake Erie. According to Cooke, et al. (2009) who conducted a mesocosm experiment on how zooplankton and phytoplankton density characteristics of eutrophic and oligotrophic conditions affect bighead carp growth, suggests the establishment of Asian carps may be more likely in the western and central basins of Lake Erie where there are more adequate food resources. These areas of the lake are also some of the shallowest regions of Lake Erie. Plankton communities within a water body are a very important indicator of water quality and a component of the lake s ecosystem since they are the base of the food web. The plankton density and species are highly variable in the lake depending on the depth of the lake, water temperature, availability of food, seasonal changes, and predatory pressures. Asian carp commonly thrive in the mesotrophic to eutrophic rivers, reservoirs and backwaters of lakes. After analyzing the eutrophic conditions presented in Figure 1 it seems that it may be possible that Lake Erie, being very eutrophic, shallow and having a history of dense algal blooms may be suitable habitat for the carp to establish a viable population, (Cook, et al. 2009). Although Lake Michigan is a very deep lake and considered oligotrophic, there are still many regions along the edges, in the bays, and potentially in the southern part of the lake where the carp have a potential to survive. Parts of the southern lake are considered eutrophic due to the intensive development and rich agricultural regions. There may be a suitable amount of phytoplankton, which causes the eutrophication in this region, for the demand of the carp to establish a population. Once the plankton in this area is consumed it may force the carp to migrate through the canals and river systems to Lake Erie where they will find an abundant source of plankton biomass to survive and establish a population. 10

11 Figure 6 The net zooplankton density of the thousands of organisms per square meter in Lake Champlain sampled throughout the 15 stations. Figure 6 suggests the highest densities of zooplankton in Lake Champlain appear to be in the southern region, along the edges, and within the larger bay areas of the lake. At lake station number 50 there were on average 250 organisms per cubic meter, with as high as 450 organisms/cubic meter. Along with lake station number 51, which is located within the same region as number 50, there were on average 190 organisms per cubic meter, with maximum counts exceeding 500 organisms per cubic meter. Lake stations 50 and 51 are both located within the Mississquoi Bay area, where there are repeatedly high algal communities during the summer months as the water warms and the phosphorus inputs increase. There are many common species of game fish that exist in each of the three lakes such as walleye, trout, small and large mouth bass, yellow perch and northern pike. Each of these recreationally and economically important species could be adversely affected if the Asian carp were introduced. The livelihood of the native fish are of major concern due to the significant overlapping diets between these fish and the planktivorous Asian carp. As indicated in the Mississippi River there is a high potential of competition for plankton biomass with the larval and adult stages of many fish species in the three lakes of concern. 3. Pathways and Connections As discussed before, Asian carp are currently present throughout the Mississippi River System and much of the Midwest but it has not quite infiltrated the Great Lakes themselves. They stand poised to do so and a number of vectors may allow them access to the lakes. 3.1 Canals The Chicago Shipping and Sanitary Canal (CSSC) is widely accepted as the most likely vector for the Asian carp (Hill 2008, Modley 2010, and Asian carp Working Group 2010). This 28 mile long canal was constructed in the early 1900s as a sewage canal to carry the waste from Chicago away from Lake Michigan and into the Des Plaines River 11

12 ( It has expanded in the last century and is now the principal connection between Lake Michigan and the Mississippi River System. As one can image, it is a major shipping canal and of high economic importance- a fact that has significant implications for the prevention of the Asian carp invasion. This will be discussed later. The Asian carp was rumored to be as close as 7 miles away from Lake Michigan but the latest monitoring results (released 3/29/10) showed the closest carp to be 70 miles downstream from the Lakes (Asian carp RCC 2010). Given that these carp have been known to migrate as many as 10 miles/day, 70 miles is not much of a buffer (Cooke et al. 2009). The CSSC is regulated by a series of locks and dams which will undoubtedly hinder the movement of the carp but few believe they will prevent their movement entirely. Meg Modley, Aquatic Nuisance Species Coordinator for the Lake Champlain Basin Program, believes that they will be able to move through these barriers because of the frequent overland flooding in the area (2010). The Des Plaines River runs close to the CSSC and is devoid of physical barriers. In events of flooding, it is feasible that the Asian carp could move between these two waterways, effectively bypassing many of the physicals barriers. The ability of these carp to travel overland in very shallow flood water is well documented and has implications for management (Degrandchamp 2006 and Wisconsin DNR 2010). 3.2 Human Facilitated Introduction If not by this canal and river system, the Asian carp may be intentionally or unintentionally introduced to the Great Lakes by humans. 3.2a Ballast Waters As an important shipping center in the USA, the Great Lakes receive heavy traffic from both domestic and international sources. These cargo ships bring with them foreign ballast waters that often get released, along with whatever else is in the holding tanks, into the lakes. Of the 184 invasive species in the Great Lakes today, 33% are believed to have come from ballast waters (Marsden E and Hauser M 2009). It is possible that with all the traffic between the Mississippi River and Lake Michigan, juvenile Asian carp could be transported in the ballast water and released into the Lake. 3.2b Escape and Release Humans, for better or for worse have facilitated significant movement of organisms throughout the world (Marsden E & Hauser M 2009). Whether it be through intentional stocking, as is the case of the Rainbow Trout and Brown Trout (Marsden and E Hauser M 2009), or bait fish release (the case of Alewife (Good S and Cargnelli L 2004)), or aquarium release (i.e some goldfish populations in Lake Champlain (Marsden and E Hauser M 2009)), humans are effective at spreading non-native species around. As previously mentioned, both the silver and bighead carp were originally introduced into US waterways as biological controls algae. This practice has decreased significantly but the potential remains and it is possible that a private landowner, unaware (or aware for that matter) of the implications, introduce these fish into the Great Lakes basin. The grass carp, another nonnative, is still utilized for biological weed control of aquaculture ponds and as juveniles they are hard to distinguish from silver carp (Stone 2008). It is plausible that in the transport of these grass carp, the silver and bigheaded get moved around as well. A final and recent potential vector is the expanding culinary market. In their native range in Asia, the carp are extensively consumed and that market is slowing getting established here (Hood 2010). As this market continues to grow it is likely that the live trade 12

13 of this fish will as well which would increase the potential for live specimens to be dumped into one or more of these lakes. Should the Asian carp become established in the Lake Michigan, Meg Modley, (Aquatic Nuisance Species Coordinator for LCBP) believes they will have no problem expanding their range to the other Great Lakes, at which point it becomes important to ask, will they make it to Lake Champlain? 3.3 Pathways and connections between the lakes Historically, these two water systems would have could have been considered isolated systems but anthropogenic activities and changes to the land have changed this. We have constructed canals, increased traffic between the lakes and developed markets for which we transport organisms all around. The potential vectors between these systems are numerous; however, for the purpose of this report we will focus on 2 main categories, canals and waterways, and human facilitated introduction. 3.3a Canals The 19 th century was a time of canal building in the Northeastern United States (Daniels 2000). From the early 1800 to the late 1870s a complex system of 22 navigation canals was constructed in New York State alone (Daniels 2000). The backbone of this system, the New York State Canal System (NYCS), extends 524 miles and connects the waters from Lake Erie, Lake Ontario, Lake Champlain, the Mohawk River and the Hudson River System (Pimentel 2005). Many authors believe that these canals have permitted the range expansion of many aquatic organisms (Daniels 2000, Pimentel 2005, & Marsden 2008). In fact, in 2000 the state of NY created a list of 39 species of fish that were believed to have expanded their ranges by migrating through these waterways (Daniels 2000). Today, the NYCS is a tourist attraction, drawing sight seers, sport enthusiasts, and anglers by the thousands every year. The miles of canals support large populations of small and large mouth bass, walleye, panfish, northern pike, blueback herring and Coho Salmon. ( The waters of the canals are nutrient rich and warm- conditions not unlike those of the Mississippi River System where the Asian carp have been thriving for the past 40 years. Meg Modley (personal interview 2010) believes that they will be able to migrate through these canals and into Lake Champlain. The network of 54 electric locks may inhibit the movement of these fish but the presence of the aforementioned species (walleye, panfish, etc) throughout the entire expanse of the canal, suggests that the locks are not impassable barriers. The fact that the Asian carp have had little problem moving past the locks in the Chicago Shipping and Sanitary Canal also suggests that they are capable of overcoming these physical barriers. Of particular concern for this study is the Champlain Canal. Constructed in 1823, this 60 mile canal connects Lake Champlain with the Hudson River and the Erie Canal (Fig. 7). One study, found that as many as 20 aquatic nuisance species arrived in the lake through canals, 12 of which are believed to have come through Champlain Canal (Marsden 2009). The Zebra Mussel and White Perch are perhaps the best known invasive species thought to have migrated into the Lake Champlain system through this canal (Malchoff 2005). 13

14 Lake Erie Figure 7. Erie, Champlain and Chambly Canals (Malchoff 2005) Like the NYCS, the Champlain Canal has shallow nutrient rich waters that seem to favor the growth of the Asian carp. It has been the principal vector the migration of invasive species into Lake Champlain in the past (Marchloff 2005) and it seems reasonable to assume that it could serve as the principal pathway for the arrival of the Asian carp. 3.3b. Human Facilitated Introduction In respect to the movement between the lakes, ballast waters and shipping don t play as important a role because of size limitations with Lake Champlain; large cargo ships can t make it up the canals or tributaries so it doesn t receive much of this traffic. However, accidental release with grass carp or intentional use as biological control agents still present potential transport methods for the Asian carp. The expanding culinary market is another potential vector for the movement of this aquatic species. The bighead carp is of particular concern because it is shipped live as a specialty food item and anytime live organisms are transported around the country there is risk of accidental escape and/or release (Kolar et al 2005). 4. Asian Carp Preventative Measures Current Asian carp preventative measures being pursued in the Great Lakes basin focus on the following four areas: 1) CSSC Underwater Electro-barrier 2) edna Sampling 3) Rapid Response Plan 4) Electro-fishing, Netting, and Targeted Removal The four main preventative measures currently being pursued will be broken down into the following sub-sections: background information, implementation, effectiveness, cost, and time scale. Following analysis of these techniques, alternative preventative measures compiled from agency documents, peer-reviewed literature, and on-going research, will be discussed as potential alternatives for Asian carp control. 14

15 4.1. Current Asian Carp Preventative Measures 4.1a. CSSC Underwater Electric Barrier The CSSC is a man-made waterway connecting the two basins, and has been identified as a known vector for transport and establishment of non-indigenous aquatic species such as the Round Goby (Neogobius melanostomus) and Zebra Mussel ( Dreissena polymorpha)( Minnesota Department of Natural Resources 2010). Figure 8: Overview of CSSC Electro-barrier System (source: USACE) In response to the identification of the main vector of transport between the Great Lakes and Mississippi River basins, the US Army Corps of Engineers constructed an aquatic nuisance species dispersal barrier which has been in operation in the CSSC since April The dispersal barriers consist of a series of steel cables that run the width of the canal and are secured to the bottom. A low voltage current is passed through electrodes at both ends of the cables creating a gradual, non-lethal electric field underwater which fish will avoid crossing (USACE 2009). The aquatic dispersal barrier in the CSSC is composed of two separate dispersal barriers maintained at different pulsating voltages, resulting in a graded electrical field. Implementation The first barrier, known as Barrier I or the demonstration barrier, is located at river mile and generates an underwater electric field that does not exceed 1 volt/inch pulsing every 4 ms at 5 Hz. Barrier I was constructed as a pilot project under the Nonindigenous Aquatic Nuisance Prevention and Control Act of Completed in April of 2002, Barrier I encompasses a 54 foot long stretch of the CSSC and spans the entire 160 foot width of the canal (USACE 2009). Barrier I was built with temporary materials and was not meant to last longer than five years (USACE 2007). Referring to Figure 8, Barrier II is a permanent barrier composed of two separate barriers, Barrier IIA and Barrier IIB. Only IIA is currently operational, while IIB is under construction and slated for operation by October Barrier II was built with several design improvements attained from testing on the demonstration barrier. It is capable of generating a more powerful electric field over a larger area. Structural modifications include the construction two sets of electrical arrays and control houses capable of functioning independently and in unison upon completion of both barriers in the fall (USACE 2007). 15

16 Completed in April 2008, Barrier 2A is 130 feet in length and located 1300 feet upstream of the demonstration barrier. Capable of generating an electric field of 2 volts/inch pulsing every 6.5 ms at 15 Hz, Barrier IIB is located 800 ft upstream of the demonstration barrier and spans the width of the CSSC. Slated for completion in October 2010 to coincide with the decommissioning of Barrier I, Barrier IIB will come online at the same operating capacity as Barrier IIA, generating an electric field of 2 volts/inch pulsing every 6.5 seconds at 15 Hz (Asian Carp Working Group 2010). Effectiveness Underwater electrical barriers have been tested in their effectiveness and have proven efficient in keeping unwanted aquatic organisms from passing the barrier. However, the exact effectiveness of such electrical barriers depends upon factors including current velocity, temperature, conductivity (Dettmers et al. 2009), and age-specificity to carp life stage (Brammeier et al. 2008). Studies conducted on the effectiveness of underwater electrical barriers have yielded positive results in their ability to stop carp from moving upstream. One study conducted by the Illinois Natural History Survey found that a hybrid integrated system consisting of an electrical barrier, coupled with an acoustic bubble current system was 83% effective in preventing adult Bighead carp from passing the barrier (MDNR et al. 2004). Another study compiled by the Minnesota Department of Natural Resources in 2004 puts the effectiveness of the barrier between 90-99% effective (Brammeier et al. 2008). University of Vermont fish expert Ellen Marsden stated upon interview in March 2010, that when properly constructed, an underwater electrical barrier should be completely effective in preventing Asian carp from entering the Great Lakes basin. An underwater electrical barrier has been proven to be an effective means to prevent aquatic invaders, especially when integrated with other behavioral barriers. However, there are documented failures of the electrical barriers and there is a large amount of uncertainty surrounding the method. Mechanical operations pose the greatest threat to the effectiveness of an underwater electrical barrier. Because the barriers are generating an underwater electric field, there is a need for a constant input of energy. If these energy inputs were to cease due to a malfunction or a power outage, the CSSC would be left defenseless to aquatic invaders (Marsden 2010). There have been documented failures associated with the locality of the barriers. In 2008, a 125 year magnitude flood enveloped the region and there was obvious overland flow from the Des Plaines River into the CSSC above the electro-barriers (Brammeier et al. 2008). Following the overland flow between the two water bodies, edna testing above the electrobarriers yielded a positive result for Asian carp (Asian Carp Working Group 2010). Although the electro-barriers may provide sufficient separation between the two water bodies, all other aquatic pathways into the Great Lakes must be capped to prevent infiltration around the barriers. Questions have also arisen pertaining to the effectiveness of the electro-barrier on different age classes of Asian carp. A preliminary feasibility study on the ecological separation of the two basins conducted by the Great Lakes Fisheries Commision in 2008 revealed that an electro-barrier is non-effective against carp in their planktonic stages (Brammeier et al. 2008). Fish at earlier developmental stages are typically much smaller than adults and require a larger current to deter their movement. According to the Army Corps of Engineers, the electro-barrier has the capacity to increase its electrical field, but this comes at the cost to human safety. Electro-barriers are currently operating at optimal capacity for deterring Asian carp while maintaining a voltage safe to boaters (USACE 2009). Also, Asian carp are known to leap several feet in their air when startled, so the potential for passing the electro-barrier through the air is a very valid concern. 16

17 Cost Barrier I has been fully funded by the federal government. As of fiscal year 2007, approximately $4 million has been spent on the demonstration barrier for design, construction, maintenance and operation. There is no set price ceiling on this project. Barrier II has been funded 75% by the federal government, while the other 25% funding is being provided by non-federal sponsors. Through Fiscal Year 2007, $8.5 million of the estimated $16 million it costs for construction and operation of the barrier had been spent (USACE 2009). Time scale Barrier I was completed with its temporary status as of April Current legislation has upgraded the status of Barrier I to be slated to become a more permanent structure. Preliminary action is in motion and Barrier I is slated to be completed in 2013 with permanent status. Barrier IIA was completed in April 2004; Barrier IIB is under construction and slated for opening in October 2010 (Asian Carp Working Group 2010). 4.1b. edna Sampling Current preventative measures being undertaken around the electro-barrier system in the CSSC have been pursued as a last line of defense separating the two basins. The electrobarrier system is in fact the only physical barrier, beyond locks and dams, preventing the spread of Asian carp into the Great Lakes. In order to determine the effectiveness of these preventative measures, a comprehensive monitoring system in all water bodies adjacent to the Great lakes is needed. One method of detection for the presence of Asian carp in water bodies has been recently developed, known as environmental DNA sampling, or edna sampling. This form of sampling was developed under the edna Program located at the University of Notre Dame (USACE 2010). edna testing analyzes water samples for trace amounts of Asian carp DNA retained in the environment. This test determines the presence of Asian carp in a water body by detecting suspended carp DNA contained in mucoidal secretions, feces, and urine. Testing involves extracting DNA fragments found in 2 L samples collected from water bodies adjacent to the Great Lakes, and identifying Asian carp based on several unique genetic markers. This method of testing does not depend upon direct observation of carp to determine their presence in a given water body, and testing can encompass a greater area and it is also more sensitive to fish presence than previous techniques (Lodge 2010). Implementation This form of testing is currently used as the basis for determining the presence or absence of Asian carp in water bodies adjacent to the Great lakes basin. edna samples have been collected and analyzed for the presence of Asian carp in areas surrounding the electrobarrier system. As of January 2010, edna results from the North Shore Channel, in close proximity to Lake Michigan, yielded positive results for Silver carp, although no specimens of Asian carp have been collected above the electro-barriers to date (USACE 2009). Currently, methods of increasing the capacity of edna sampling are being pursued by federal agencies to sample for Asian carp in target areas. As defined by the Great lakes Fishery Commission, target areas adjacent to the electro-barrier system and canal system connecting the two basins are being extensively monitored utilizing the edna method. Coupled with the increased effort in sampling, further calibration methodology is needed, and sample analysis capacity must increase. With $940,000 in funding granted under the current control strategy framework, the US Army Corps of Engineers is currently partnering with the 17

18 University of Notre Dame to increase sample analysis capacity and calibrate methodology (Asian Carp Working Group 2010). Effectiveness Although the edna method of sampling allows for greater ease of detection and greater area of detection, there are pitfalls to this approach. While edna sampling can determine the presence of Asian carp, there is no method of determining the logistics of the specimen(s) the sample was collected from. edna sampling currently cannot determine the number of Asian carp present in a water body or pinpoint their exact location, it can only tell if they are present. Also, demographic population parameters are not addressed, this form of sampling does not yield information on age, size, or sex of the fish present in the water body (Lodge 2010). These factors are critical in determining the best possible management practice to be utilized during management, and techniques for determining these factors are currently being developed. Cost Current costs associated with increasing the sampling efforts in water bodies adjacent to the two basins total to $2,600,000. Costs associated with increasing the analyzation capacity and calibrated methodology at the University of Notre Dame and USACE Research Laboratory totals to $940,000 (Asian Carp Working Group 2010). Time Scale This is the current method of Asian carp detection utilized for Asian carp identification in the Great Lakes basin. Methodology if being further refined as delineated by the current control strategy framework. 4.1c. Rapid Response Program We believe it is still critical to support and defend the electric barrier while it is down for maintenance, said IDNR Assistant Director John Rogner. The barrier remains our most effective weapon against this very aggressive invasive species (IDNR 2009). The electro-barrier system present in the CSSC remains the only physical barrier impeding the spread of Asian carp into the Great Lakes. Due to the nature of the structure of electro-barriers, maintenance is required every 4-6 months (USFWS 2010). This routine maintenance requires the electro-barriers be turned off for personnel safety issues. To protect the Great Lakes from invasion during this maintenance period, a Rapid Response Program has been initiated. The Rapid Response Program, as outlined by the Asian Carp Rapid Response Working Group in its February 2010 report, is a simple but effective means to quell the spread of Asian carp past electro-barriers during routine maintenance. Rotenone was chosen by the US EPA as the most effective means for control of Asian carp in the CSSC. Rotenone is a chemical derived from the roots of tropical and subtropical plants which inhibits biochemical processes in fish at a cellular level, resulting in death. Although it is not targeted specifically to Asian carp, Rotenone is non-persistent and rapidly breaks down following application into water and carbon dioxide (USEPA 2007). The Rapid Response Program was first implemented in December 2009 during routine maintenance. 2,200 gallons of Rotenone was applied along a 5.7 mile stretch of the CSSC surrounding the electro-barrier to exterminate Asian carp present in the region. Resultant from this Rotenone application was the recovery of only one Bighead carp out of 90 tons of dead fish, found nearly 500 ft above the Lockport Lock (USFWS 2010). 18

19 Implementation Rapid Response Plans are laid out by the Asian Carp Rapid Response Working Group in response to routine maintenance on the electro-barrier system. Implementation occurs approximately every 4-6 months. Effectiveness The implementation of the Rapid Response Plan in December 2009 yielded only one Asian carp, although others were reportedly killed by the Rotenone application but not recovered post-response. Rotenone is highly effective in killing all fish in a targeted area, with minimal downstream impact. It rapidly degrades into carbon dioxide and water, ceasing to effect fish after a few hours, and becoming non-toxic after 4-6 weeks (USEPA 2007). Rotenone has been tested and determined to be highly effective in its purpose of killing target fish species. One study puts the effectiveness of piscicides, such as rotenone, at 65-95% effective (Brammeier 2008). Cost The current cost of rotenone is very high, with one figure from Wildlife Review putting the cost of Rotenone at $1/acre foot (Gebhards). Expected costs for large scale application can be derived from the implementation of the December 2009 Rapid Response Program, applying 2,200 gallons of Rotenone at a cost of $3 million (Hood 1999). Time Scale Rotenone degrades fairly rapidly after application, ceasing interactions with fish after several hours and ceasing to be toxic following a 4-6 week period (Gebhards). Application of Rotenone in accordance with the Rapid Response program will be in concert with prescheduled maintenances of the electro-barriers. 4.1d. Electro fishing, Netting, and Targeted Removal In response to the Control Strategy Framework published in February 2010 and in conjunction with the development of edna identification methods, an aggressive regiment of electro fishing and netting has been instated to suppress Asian carp populations above the electro-barrier system. The USFWS and the Illinois Department of Natural Resources (IDNR) have utilized data collected by the edna method to identify areas above the electrobarrier system where Asian carp have been detected (Asian Carp Working Group 2010.). Likely areas that have been identified as hotspots, include areas adjacent to: warm water discharges, wastewater treatment plant outfalls, tail waters of locks and dams, marina basins, barge slips, and other slack water areas (Asian Carp Working Group 2010). Once target areas have been established (indicated by a positive presence of Asian carp edna), efforts will be concentrated to confine individuals into an area where they will be susceptible to removal via Rotenone or nets (Asian Carp Working Group 2010). Methodology will consist of driving Asian carp into confined areas utilizing electro fishing gear, light, or sound systems. Commercial fishermen will be enlisted to set block necks to prevent flight of the Asian carp. Carp will then be confined utilizing block nets and removed with the application of rotenone. 19