Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 1 of 40

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1 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 1 of Hidden Valley Rd. Kitchener, ON N2C2S4 (519) Dynamic Patterns of Fish Production, Fish Exploitation and Ecological Change in Lake Erie Prepared by: Christopher Bunt, PhD and Heinrich Bier Prepared for: Frost Brown Todd LLC One Columbus 10 West Broad Street, Suite 2300 Columbus, OH APRIL

2 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 2 of 40 TABLE OF CONTENTS TABLE OF CONTENTS... 2 EXECUTIVE SUMMARY... 3 INTRODUCTION... 4 FISH PRODUCTION AND THE HISTORY OF COMMERCIAL FISHERIES IN LAKE ERIE... 4 LAKE ERIE MANAGEMENT UNITS... 5 HISTORY OF THE OHIO SPORT FISHERY IN LAKE ERIE... 6 HISTORY OF OVER-EXPLOITATION... 7 ENVIRONMENTAL FACTORS AND FISH PRODUCTION... 8 CARRYING CAPACITY... 8 ENVIRONMENTAL DEGRADATION... 9 POLLUTION... 9 EXOTIC SPECIES Dreissenid Mussels Round Gobies DISEASES AND PARASITES CHANGING CLIMATE CURRENT STATUS OF THE LAKE VALUE OF COMMERCIAL AND SPORT FISHERIES HARVEST QUOTAS DEMOGRAPHIC TRENDS IN OHIO SPORT FISHERIES SPORT ANGLING EFFORT UNDER-EXPLOITATION CAVEATS ABORIGINAL FISHERIES ON THE GREAT LAKES CONCLUSIONS REFERENCES FIGURES:

3 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 3 of 40 Dynamic Patterns of Fish Production, Fish Exploitation and Ecological Change in Lake Erie EXECUTIVE SUMMARY Lake Erie is the smallest, shallowest, warmest and most productive of the five Laurentian Great Lakes. The lake produces huge amounts of fish, many of which are important to commercial fisheries, sport fisheries and overall ecological structure and function. There have been significant changes in the lake ecosystem over the last 100 years related to pollution, habitat destruction, overexploitation, introduced species and climate change. These perturbations have been countered through pollution control measures and phosphate abatement programs, habitat creation and provision of fish passage facilities, Total Allowable Catch limits (TACs) for commercial fisheries, bag limits for sport anglers, size limits, spatial/temporal angling restrictions, adaptation of native fisheries to non-native (introduced) species through predation and thermally mediated shifts in behaviour and reproduction. Conditions in Lake Erie are dynamic and the fish community displays remarkable plasticity in its response to change. Significant declines of several major fish stocks were related to combinations of factors including pollution, habitat degradation, over-exploitation, the introduction of zebra mussels and round gobies, and climate change. The Clean Water Act reduced the amount of nutrients flowing into the lake and ideal environmental conditions in the mid 1980s caused the population of walleye to soar. In fact, it is likely that walleye in the late 1980s exceeded the carrying capacity of the lake. This coincided with a major influx of anglers from the baby-boomer generation. During the late 1980s invasive dreissenid mussels became well established and the changes they had on the lake were unmistakable. Populations of walleye, perch and several other species declined initially, but have since peaked to near record levels. This has occurred as a result of an exceptionally strong 2003 year-class that has likely resulted from ideal environmental conditions, pollution control, adaptation to invasive species, trophic shifts that have increased the abundance of benthic prey items such as Hexagenia, and effective fisheries management. Increased fish abundance has not been met with increased interest in sport angling in Lake Erie. Sport angling effort, particularly in Ohio has declined steadily since the 1990s (except for a slight increase in 2006). Walleye harvest is reserved for exclusive use by the sport angling industry in Ohio, while in Ontario the majority of walleye and yellow perch are harvested commercially. Ohio received 51% of the TAC for walleye (2.76 million fish) and 43 % of the TAC for perch (4.92 million pounds) in Ohio s allocation of the walleye TAC has been under-harvested since the late 1980s. Several species are underutilized in Lake Erie and following examples of well-managed aboriginal fisheries on the Great Lakes there is no logical reason to exclude participation of aboriginal, or tribal commercial fisheries that operate within scientifically-determined TAC allocations within the Ohio waters of Lake Erie. 3

4 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 4 of 40 Adhering to TAC allocations would mean that current and projected sports fishing stocks would not be negatively affected. INTRODUCTION Lake Erie is approximately million acres in size yet it is the smallest of the Laurentian Great Lakes (Ryan el al. 2003). It is also the shallowest and most southerly of the five Great Lakes, making it the most productive (Egerton 1987; Ryan et al. 2003). Lake Erie historically supported the world s largest freshwater fishery and currently still has the world s largest freshwater fishery by value of landed fish (Munawar et al. 2005). The history of the lake is one of drastic change related to human impacts which have subsequently caused the most dramatic ecological transformations experienced by any of the Great Lakes. This has generated a significant amount of local and international attention and it has forced all bordering states (e.g., Michigan, Ohio, Pennsylvania and New York), and the province of Ontario to work together to achieve the goals and desires of all of the different user groups. Currently the user groups that demand the most attention are the commercial and sport fishing industries. The sustainability of both of these industries is contingent on conservation practices predicated on reliable long-term scientific data and adaptable management recommendations. This report is an examination of the biological and ecological history of the commercial and sport fisheries of Lake Erie coupled with a review of pertinent fisheries data related to patterns of fish production, fish harvest, commercial fishing effort, sport angling effort and catch rates for selected fish species. Discussion is provided in the context of the potential for an aboriginal (tribal) commercial fishery in the Ohio waters of Lake Erie. FISH PRODUCTION AND THE HISTORY OF COMMERCIAL FISHERIES IN LAKE ERIE The historical and contemporary immensity of fish production in Lake Erie is well documented. By 1830, fishing in Lake Erie had begun to shift from catching fish for personal consumption to a commercial market. Ohio passed its first state commercial fishing laws in The industry steadily grew as transportation was enhanced through improvements to canal and railroad systems. By the 1870 s refrigeration also became a major factor in the expansion of commercial fisheries and it appeared that fish stocks in Lake Erie were limitless. By 1890, commercial fishing operations were large employers in Ohio (Loveday 2007). The first signs of declining fish stocks were documented in In 1873 the state of Ohio established a fish commission to deal with the declining fish populations (ODNR 2005). Since the 1900s, fisheries biologists have documented species shifts from lake herring (Coregonus artedi), lake trout (Salvelinus namaycush) and sturgeon (Acipenser fulvescens) to less valuable species such as carp (Cyprinus carpio), freshwater drum (Aplodinotus grunniens) and catfish (Ictalurus punctatus). The lake 4

5 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 5 of 40 trout collapse at the turn of the 20 th century was the first major fishery collapse experienced by the commercial industry (Ryan et al. 2003; Munawar et al 2005). In the 1920 s lake whitefish (Coregonus clupeaformis) had all but disappeared from the Eastern Basin, where they were the main target of the fishery. This was following closely by the lake herring fishery collapse, from 32.3 million pounds in 1924 to 5.7 million pounds in 1925 (Loveday 2007). These stocks continued to do poorly through the 1940 s and early 1950 s (Ryan et al. 2003). During the late 1950 s the bluewalleye (Stizostedion vitreum glaucum) was extinct. This period culminated with large declines in the walleye (Sander vitreus) fishery in the 1960 s and early 1970 s (Ryan et al. 2003; Munawar et al. 2005). Harvest of sauger (Sander canadensis), a close relative of the walleye, also declined to near zero by 1960 (Ryan et al. 2003). By the 1980 s walleye and whitefish stocks began to recover and harvest levels once again increased. Yellow perch, currently the most important commercial species by weight has suffered from periods of instability, especially during the early 1990 s but over-all, remained a strong fishery (Ryan et al. 2003, LEYPTG 2006). In 1984 the state of Ohio banned the use of gill nets and bought out all the commercial gill net licenses, which meant walleye could no longer be commercially harvested in Ohio (Hushak et al. 1986). At present, the only commercial fishery for walleye is in Ontario. Since the early 1980 s, state and provincial regulating bodies have worked cooperatively, by sharing data and responsibilities to manage the fisheries and quotas for each management area of Lake Erie (Figure 1). By agreement, the Province of Ontario and four states (Ohio, Michigan, Pennsylvania and New York) annually establish and allocate the Total Allowable Catch (TAC) among themselves for all commercial fishing, based on scientific and quantitative studies of selected species of fish in Lake Erie. Ontario has by far the largest commercial fishing industry represented by the Ontario Commercial Fisheries Association that works in partnership with the Ontario Ministry of Natural Resources (OMNR) who in turn works with the four other state departments through the Lake Erie Committee (LEC). In Ontario, daily catch logs of walleye, yellow perch and whitefish are carefully monitored and quotas are strictly enforced by stiff fines and penalties. Smelt, white bass and white perch are also important to the Ontario commercial fishery and are considered non-quota species. Contemporary commercial fisheries employees realize that they must fish responsibly and work cooperatively with regulating bodies if they are going to have a viable and sustainable industry. LAKE ERIE MANAGEMENT UNITS Lake Erie is divided into a series of four management units (MU) for yellow perch and five management units for walleye (Figure 1). Over 2.24 million acres of Lake Erie is under the jurisdiction of the state of Ohio (ODNR 2006) and are in MU-1, MU-2 and MU-3. In the western basin of Lake Erie, walleye are considered to be one large stock. There is very little sport angler effort for walleye in Ontario and most sport harvest of walleye in Canada is in MU-1 (Figure 2). 5

6 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 6 of 40 A quota system is used to regulate harvest of commercially and bag limits are used in the sport angling fishery for important fish species in each of the Lake Erie management units. The quota system involves the establishment of annual TACs and proportional division across interstate and international boundaries. In Ontario, the provincial share of the TAC for walleye is met annually almost exclusively through the commercial fishery (Figure 3), while in Ohio, all of the walleye are harvested through the sport fishery (Figure 4). In contrast, the share of the TAC for perch is met annually in Ohio by both commercial (trapnet) and sport anglers, while in Ontario, the TAC allocation is met almost exclusively through the commercial gillnet fishery. Since 1984, TAC allocations have been effective in controlling harvest to minimize the potential of overexploitation of quota species. HISTORY OF THE OHIO SPORT FISHERY IN LAKE ERIE Sport fishing has a relatively short history in Lake Erie. During the late 1970 s and early 1980 s the sport fishing industry grew almost exponentially. Walleye were the most exploited sport fish in Lake Erie (Hushak et al. 1986; Kuehn et al. 2005) followed by yellow perch. Pollution control and subsequent improvements in water quality were attributed to two exceptional year classes that caused walleye stocks to rebound in the 1980 s to a point where they appear to have overshot the carrying capacity of Lake Erie (Lichtkoppler 1992; Knight et al. 1999). The charter fishing industry in Ohio responded on a massive scale, by growing from just 46 licensed charter boat operators in 1975 to 694 in The number of licensed operators finally peaked at 1211in 1990 (Lichtkoppler 1992; Kuehn et al. 2005). The profusion of anglers overexploited the walleye fishery and exceeded the TAC by % in the late 1980s (Lake Erie Walleye Task Group 2006). By 2002 there were 765 licensed charter boat operators targeting walleye and perch on Lake Erie (Kuehn et al. 2005). Sport anglers harvested far more walleye than the commercial industry in Ontario during most of the 1980 s (LEWTG 2006). Furthermore, population estimates and harvest estimates of walleye do not consider delayed mortality of undersized of unwanted fish that are released by sport anglers (Lester et al. 2005). Even though gill nets were banned in 1984, TACs were implemented, commercial harvest of walleye was banned in Ohio, and size limits were established, walleye stocks again declined in the late 1990s. The decline in perceived quality of the Ohio sport fishery was felt most severely by the commercial fishing community in Lake Erie, particularly in Ontario. The size and influence of the Ohio Charter Boat Association in particular, overshadowed the influence of the commercial industry in terms of political leverage and lobbying power. The Ohio Charter Boat Association blamed the Ohio commercial industry for perch declines, which at this point had less than 40 trapnet licenses in Ohio (OLSC 2006), and the Ontario commercial walleye fishery, for the most recent collapse. The Ohio Charter Boat Association failed to recognize demographic shifts and the fact that the over-all economy in the United States was relatively weak during the early 1990 s. Public concern related to fish consumption health advisories and fish diseases (Kuehn et al. 6

7 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 7 of ) also contributed to reductions in angler effort. The Ohio Charter Boat Association also failed to recognize that the similar declining trends were occurring at all of the other Great Lakes, despite the fact that the charter boat industries on the other Great Lakes were focused primarily on trout and salmon and not walleye (Kuehn et al. 2005). Clearly, declining walleye stock in Lake Erie was only one piece of the puzzle surrounding reduced sport angler effort in Lake Erie. The sports fishing industry in Ohio has recently lobbied for all existing trap-net fisheries in Ohio to be bought by the state. Bill 609 would have seen the existing 40 commercial licenses purchased for approximately $4 million based on recent dockside landings of yellow perch (OLSC 2006). The bill proposes the purchase of the remaining licenses at a modest price of $1.92/lb of yellow perch. This price based on weight harvested and not the TAC. By some estimates, the buyout could cost as much as $20 million. Although this bill was defeated in December 2006, a second bill designed to restrict the commercial fishing industry was introduced in March HISTORY OF OVER-EXPLOITATION The first major changes in Lake Erie were noted in the 1872 Milner Report that indicated that there was the impression of an alarming diminution of food fishes (Loveday 2007). By the turn of the 20 th century populations of certain species had begun to crash. Since then overexploitation, pollution and poor fishery management practices have been major factors that contributed to the decline of several other fish stocks. As the human population expanded, human reliance on the lake grew, while the environment was simultaneously being degraded physically, chemically and biologically. The completion and successive improvements of both the St. Lawrence Seaway and Welland Canal facilitated commercial fisheries but also caused the introduction of many parasites, diseases, as well as non-native fish and other invasive species (Koonce et al. 1996; Munawar et al. 2005). Historically, stocks were not assessed until harvest levels were in dramatic decline. Lake trout, lake whitefish, sturgeon, herring, walleye were all harvested to near extinction. Blue walleye, or blue pike, as they are sometimes referred to, went extinct in Lake Erie in the 1950s. Since the early 1970 s agreements and cooperation between the governing agencies surrounding the lake, have lead to reliable stock assessment techniques and the establishment of quotas that have largely eliminated over-exploitation of fish in Lake Erie. There has been no commercial overfishing since the establishment of ITQs (Individually Transferable Quotas) in In contrast, the TAC has been exceeded several times since 1984 by sport anglers in Ohio (Figure 9). In 1985, the TAC for walleye was overharvested by approximately 1 M fish, and the TAC was exceeded each year from by Ohio sport anglers targeting walleye (LEWTG, 2006, Figure 9). In 1985, and 1987, Ontario sport anglers also exceeded the TAC by 0.5 M and 0.75M fish, respectively. 7

8 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 8 of 40 ITQs are designed to reduce the probability of overexploitation and are designed specifically to protect fish stocks. There are also gear restrictions (mesh sizes, net dimensions) as well as seasonal restrictions to protect spawning fish and spatial restrictions to protect spawning areas. For sport anglers there are bag limits, size restrictions and spatial/temporal regulations designed to for fish protection and conservation. Stocking has also enhanced introduced fish populations such as rainbow trout (Oncorhynchus mykiss) in some areas of Lake Erie. ENVIRONMENTAL FACTORS AND FISH PRODUCTION Most evidence suggests that large year classes of yellow perch and walleye are driven by environmental factors and are the result of increased egg/larval survivorship and not simply the number of spawning fish in the standing population. Environmental factors such as spring freshet volume and duration, rainfall intensity and duration and the liberation of nutrients are considered to be more important than harvest on year class strength and walleye production (Madenjian et al. 1996, LEC 2005). Other factors that limit year class strength include predation by other fish, forage biomass and forage availability (LEC 2005). The importance of spawning stock size is masked by environmental factors such as variation in water temperature, rainfall and severe wind events. Recently, large year classes of walleye have been produced by moderate to large populations of adult fish and ideal environmental factors have contributed significantly to year-class strength (LEC 2005). CARRYING CAPACITY A thorough discussion of factors affecting the carrying capacity of Lake Erie for yellow perch, walleye or any other fish species is beyond the scope of this report. In general, however, the carrying capacity of Lake Erie has been significantly impacted over the past century. The most important factors that have affected carrying capacity for walleye include 1) direct competition and interference competition from invasive and non-indigenous species such as dreissenid mussels and gobies, 2) environmental changes resulting from phosphate abatement programs, increased water clarity and global warming and loss of habitat from pollution, development, 3) barriers to migration and the implementation of fishways (Bunt et al. 2000), spawning shoal damage etc. Several shifts in trophic dynamics in Lake Erie have been attributed to these and other sources (Ryan 2003). According to the LEC (2005) the maintenance level of walleye in Lake Erie is between 25 M and 40 M fish. Population sizes less than 15 M fish indicate that the fishery is in crisis, while a population size > 40 M walleye (not dominated by a single year class, and older than 2+ years) indicates a high quality fishery (LEC 2005). The numbers of walleye estimated from Lake Erie have increased from 2000 to 2005, to the point that in 2005, the walleye fishery is rated as high quality (LEC 2005) with a population size of 46 M fish. The apparent increase in walleye population is not 8

9 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 9 of 40 necessarily a reflection of an increased carrying capacity, but may be more indicative of improvements in fisheries management, improvement in access to fish habitat, changes in trophic dynamics and/or increased availability of forage, as well as a strong 2003 year class. ENVIRONMENTAL DEGRADATION Habitat loss has played a large role in the decline and shift in the composition of Lake Erie fish stocks. Since the early 1800s, fish populations in the western and central basins of Lake Erie have experienced loss and alteration of significant habitat (Koonce et al. 1996; Ryan et al. 2003; Munawar et al. 2005). Physical changes include the damming, deterioration, channelization and deforestation of many of the streams, rivers and tributaries that flow into Lake Erie. These changes have had significant impacts on walleye since this species typically spawns in rivers. Further changes in Lake Erie include shoreline modification, loss of wetlands, deterioration and loss of nearshore spawning and nursery areas due to siltation, nutrient loading, infestation of dreissenid mussels (zebra and quagga mussels), invasion of round gobies, and finally sand and gravel extraction (Koonce et al. 1996; Ryan et al. 2003; Munawar et al. 2005). Pollution is considered to have had one of the largest and most significant impacts on the fisheries of Lake Erie. POLLUTION By the turn of the 20 th century it became clear that water quality and overall conditions in Lake Erie were deteriorating (Loveday 2007). By the 1960 s the lake was in serious trouble and nutrient enrichment was cited as one of the major problems (Koonce et al. 1996; Ryan et al. 2003). In fact, phosphorus levels doubled between 1942 and 1958 (Ryan et al. 2003). Urban runoff, domestic sewage, industrial wastewater and agricultural runoff (mostly fertilizer) were all principle sources of phosphorus and nutrients that resulted in eutrophication (Ryan et al. 2003; Munawar et al. 2005). Eutrophication caused a lake-wide shift in ecosystem type from mesotrophic (presettlement), to hyper-eutrophic in the western basin, eutrophic in the central basin and from oligotophic to mesotrophic in the eastern basin. Research conducted in the 1950 s and 1960 s showed that elevated phosphate resulted in a proliferation of algae and bacteria that decompose algae. In fact, the concentration of algae near Cleveland increased by a factor of 12 between 1930 and 1960 (Eos, 1971). Bacterial decomposition of algae consumed oxygen in the bottom waters of the lake and this negatively impacted species that require high oxygen concentrations as well as important native benthic organisms. This resulted in a species shift and major decline of species that required more mesotrophic conditions (walleye, blue pike, sauger and yellow perch) and oligotrophic conditions (lake trout, sturgeon, whitefish and herring). Simultaneously, species that were tolerant of low oxygen flourished (such as worms, midges, catfish, carp etc.). By the 1970 s it was clear that something had to be done and in 1972 the Great Lakes Water Quality Agreement was signed by Canada and the US to curtail the flow of 9

10 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 10 of 40 polluted effluent. By the 1980 s the lake began to show signs of recovery as phosphate levels dropped and fish stocks (walleye and whitefish) began to increase along with benthic macro-invertebrate communities (Koonce et al. 1996; Ryan et al. 2006). EXOTIC SPECIES The most serious threat to the Great Lakes other than declining water levels, are nonindigenous and invasive species that affect all trophic levels within an ecosystem (Munawar et al. 2005). Some estimates place the number of invasive species in the Great lakes as high as 170 (Munawar et al 2005). The completion and improvements to the Welland Canal during the first half of the 20 th century and the opening of the St. Lawrence Seaway in 1959, resulted in the introduction of many exotic species through increased shipping traffic and ballast water discharges in the Great Lakes (Munawar et al. 2005). Some of the more notable exotic fish introductions have been smelt, white perch, alewife and the round goby. Some of these species have become important commercially and in the sport angling industry either by being targeted directly, or through their function as a food source for other fish species (Ryan et al. 2003; Munwar et al. 2005). Invertebrate invaders include spiny water fleas (Bythotrephes longimanus and Cercopagis pengoi) and dreissenid mussels (Dreissena polymorpha) (Koonce et al 1996; Ryan et al. 2003; Munawar et al. 2005). Although many other species have been introduced, dreissenid mussels and round gobies have had the largest and most profound effects on food-web structure in Lake Erie. Dreissenid Mussels Dreissenid mussels (zebra mussels and quagga mussels) were reported in Lake St. Clair in the mid 1980 s and were found in the Eastern Basin of Lake Erie by 1989 (Schloesser and Metcalfe-Smith 2005). Zebra mussels were established in 1988 (Munawar et al. 2005, Depew et al. 2006) throughout Lake Erie, beginning in western basin. The introduction of zebra mussels changed the lake to a more oligotrophic rather than eutrophic ecosystem (similar to pre-pollution conditions). The increase in water clarity caused another shift in the fish community structure. Furthermore, the colonization of zebra mussels shifted nutrient cycling in the lake to a more benthic, as opposed to pelagic food web. Zebra mussels filter large amounts of phytoplankton and small zooplankton (Bunt et al. 1993) and have caused a significant transformation in the plankton community structure of Lake Erie (Depew et al 2006). Dreissenid mussels sequestered a large proportion of the lake s nutrients and overall biomass into the benthos (Johnson et al. 2006). This caused significant changes in fish stocks (Figure 5), causing many species to decline or move to different areas of the lake (Ryan et al. 2003). Stock declines of yellow perch, walleye, smelt and whitefish - all commercially important species - were documented following the invasion and proliferation of zebra mussels (Ryan et al. 2003; Munawar et al. 2005). 10

11 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 11 of 40 The reduction of turbidity has had some positive effects. For example, the benthic macro-invertebrate community and has experienced a massive return of Hexagenia (burrowing mayflies) (Ryan et al. 2003; Bridgeman et al. 2006). Hexagenia are a major food source for percids, including young walleye and yellow perch. (Richie and Colby 1988; Ryan et al. 2003; Bridgeman et al. 2006). Increased water clarity and increased penetration of sunlight has also facilitated the growth of large aquatic macrophytes beds that fish use for habitat. Zebra mussels have declined since the 1990 s in Lake Erie partly due to population stabilization, fish predation and the introduction and rapid spread of the round goby (Depew et al. 2006). Round Gobies Like many other exotic species, the round goby was introduced into the Great Lakes via ballast discharges during the 1990 s (Ryan et al. 2003; Johnson et al. 2005). Since then, gobies have become established in high densities in near-shore habitats (Johnson et al. 2005; Munawar et al. 2005). Zebra mussels are the main diet for adult gobies and this has once again resulted in a feedback related ecosystem shift in Lake Erie (Johnson et al 2005; Munawar et a. 2005). Energy that was previously locked up in zebra mussels is now being integrated into the food-web via gobies (Ryan et al. 2003; Johnson et al. 2005; Munawar et al. 2005). There has been a shift to a more benthic oriented fish community as many fish, including but not limited to walleye, yellow perch, burbot and smallmouth bass, are increasingly including gobies as a large portion of their diet (Ryan et al. 2003; Johnson et al. 2005; Munawar et al. 2005). There is some evidence that fish populations have responded with increases in abundance (Figure 5). DISEASES AND PARASITES The removal of natural barriers such as Niagara Falls has allowed Lake Erie to be colonized by parasitic species such as sea lamprey. Sea lamprey was first discovered in the 1950 s after completion of the Welland Canal (Munawar et al. 2005). Efforts to control sea lamprey did not begin in Lake Erie until 1986 and survival of lake trout (note that there is still no evidence of natural reproduction of lake trout in Lake Erie) increased noticeably only one year later (Ryan et al. 2003). More recently, the lake has been experiencing problems with botulism and viral haemorrhagic septicaemia (VHS) that has been causing fish kills among some species in some areas of the lake, particularly yellow perch and freshwater drum in the central basin. Sea lampreys have been partially controlled through sterile male releases, lampricide programs and lowhead barrier dams. VHS remains an issue of concern, despite the lack of epidemiological or population-wide impacts. It is possible that VHS is a densitydependent source of natural mortality and recent fish kills are evidence of high fish biomass of species that have overshot the carrying capacity of the lake, coupled with stress related to some other factor such as water temperature or pollution. 11

12 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 12 of 40 CHANGING CLIMATE The effect of climate change on the Great Lakes is in the process of being studied and modelled. Jones et al. (2006) presented data that shows water temperature in Lake Erie has increased from , particularity in the winter and summer months. Models predict lower lake levels, less ice cover and lower annual runoff, but as with any type of forecast, certainty remains low (Jones et al. 2006). The overall effect of rising water temperatures on fish stocks must be evaluated in concert with all of the other known factors that affect fish production. A multitude of components related to changing habitat need to be integrated in order to fully understand the overall effect of climate change (Jones et al. 2006). The potential for effect or ability to predict the real effect of climate change on the fisheries of Lake Erie is beyond the scope of this report. However, Lake Erie is dynamic and as history has shown, the fish community will adapt accordingly. CURRENT STATUS OF THE LAKE VALUE OF COMMERCIAL AND SPORT FISHERIES In Ontario, the estimated value of commercial fisheries is significant. For example the landed value for freshwater fish in Ontario is between $30 M and $40 M per year, with a large portion coming from Lake Erie (Kinnunen 2003). In the US, the landed value is approximately 1/10 th of the Canadian landed value. In contrast, the US valued its sport fishery in the Great Lakes at over $1 B in 1998 (Loveday 2007). It was reported that total overall expenditures from Great Lakes trips were $1.27 billion in down almost $300 million from 1985 (Kuehn et al. 2005). These figures should be treated with caution since they are a sum total of all expenses incurred by sport anglers during fishing excursions and may therefore be artificially inflated. These values do not necessarily reflect the true value of the fishery but may be more indicative of the value of the perceived potential for the fishery to incite excitement that encourages the pursuit of the angling experience. HARVEST QUOTAS The quota system has been developed on a species by species basis within the Great Lakes. From a commercial perspective, there are two groups of species. The first group includes current quota species such as whitefish, yellow perch, white perch and white bass in Ohio. In Ontario current quota species include whitefish, smelt, yellow perch and walleye. The second group of species is the non-quota species and this includes the remainder of exploitable fishes in Lake Erie. Walleye are a prohibited commercial species in Ohio to conserve stocks for sport fishery exploitation. 12

13 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 13 of 40 Furthermore, minimum size limits exist for white bass, white perch and yellow perch to protect fish stocks in Ohio. Little effort is made to monitor instantaneous harvest through the sport fishery. As such, the quota system and stock assessment techniques are not rapidly adaptable and may require at least a two year lead time to implement new conservation strategies if required. According to the Great Lakes Fishery Commission there is the potential that large numbers of yellow perch and walleye are being removed from Lake Erie without detection (i.e., effective harvest). This is occurring through catch and release practices that result in delayed mortality associated with handing, hooking injury and barotrauma (Lester et al. 2005). Minimum size limits of walleye (15 implemented in Ohio in 2004) as well as the popularity of controlled-depth angling (downrigging) results in the release of large numbers of undersized fish that may succumb to hooking mortality, handling mortality, barotrauma and post-angling predation. These fish, as well as fish caught by shore-based anglers, are unaccounted for when estimates of harvest and biomass are calculated (Lester et al. 2005). In contrast to the commercial fishery, there is no control of effective harvest by the sport angler. DEMOGRAPHIC TRENDS IN OHIO SPORT FISHERIES Currently, one out of every 10 Americans has a fishing license. The state of Ohio sold 1, sport fishing licenses in 1997 which generated 74 % of the $16, used to operate the state s fisheries management program (Epifanio 2000). The number of anglers in America peaked in the mid-1980s at 31.5 million. At the time, anglers represented approximately 19 percent of the U.S. population. The number of sport anglers in 1985 was million for the entire Great Lakes Region (Kuehn et al. 2005). By 1991 this number decreased to million and by 2001 there were only million licensed anglers (Kuehn et al. 2005). Even though the sport fishery in Ohio s portion of Lake Erie is unique in that it is focused primarily on walleye (Lichtkloppler 1992), while the remainder of the Great Lakes sport fisheries are focused on trout and salmon, the decreasing trend in participation of sports fisheries was evident throughout the Great Lakes for primarily the same reasons (Kuehn et al. 2005) and not necessarily because of a decrease in fish stocks as indicated by the Ohio Charter Boat Association. The decreasing trend of participation in Ohio s sport fishery in Lake Erie can be attributed to the following: 1) The Baby boomer generation was aging. This segment of the human population was retiring in large numbers in the 1980s and angling became a popular past-time for nearly a decade. In many cases, angling did not become popular among the children, grandchildren, nieces, nephews etc of the babyboomer anglers. Angling does not appear to be an overly common past-time among the so-called Video game generation 2) Escalating cost of fuel and insurance significantly increased the overall expense of sport angling on Lake Erie. Over 79 % of charter boat customers 13

14 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 14 of 40 traveled over 50 miles, each way for a day of fishing on Lake Erie in Ohio (Kuehn et al. 2005). These increased costs have resulted in the observed declines in the number of charter boat licenses as well as resident fishing licenses sold since the early 1990s. 3) There is a perception among some members of the population that consuming fish from the Great Lakes is unhealthy due to pollution and contamination. Discussions related to fish contamination have created much controversy. Many consumers err on the side of caution and avoid eating fish (Knuth et al 2003). The omega-3 fatty-acids and proteins in fish have been shown to significantly reduce the risk of cardiovascular disease and facilitate neurodevelopment, meaning it is important for nursing mothers and women of child-bearing age to consume fish (Knuth et al. 2003; Mozaffarian and Rimm 2006). Most studies have shown that health benefits achieved by consuming fish far outweigh the risks from contamination, even for children and pregnant women (Knuth et al. 2003; Mozaffarian and Rimm 2006). Some agencies set guidelines on safe levels for fish consumption and adjust recommendations to more modest quantities for children, women of child-bearing age and pregnant/nursing women. For example, the Ontario Guide to Eating Sport Fish includes the following recommendations for the most sensitive members of the human population who consume fish from Lake Erie in (MOE 2007): Management Unit 1: Yellow perch, up to 8 meals a month, walleye 55cm (22 ) or less 4 meals a month, whitefish 45cm (18 ) or less up to 4 meals, Smelt - zero, rainbow trout - zero and coho salmon - zero (the chance of caching one in MU-1 is low). Management Unit 2: the consumption size and/or limits of all these species increases. This is likely due to the relative proximity of MU-1 to the Detroit River and its associated contaminant load. SPORT ANGLING EFFORT Figure 3 and Figure 9 shows changes in the walleye sport fishery in Ohio and Ontario and Figure 2 indicates no response in angler effort despite the biggest year class for walleye in history during There was a slight increased in sport fishing effort for walleye in There was no increase in angler effort as occurred during the large year classes of the 1980 s. This is largely due to the demographic shift of the sport angler population of Ohio (as previously discussed). Figure 6 shows walleye CPUE from 1975 to present and shows that catch rates have jumped to levels similar to those in the 1970s and 1980s. Figure 2 and Figure 8 shows no significant increase in angler effort despite significant increase in catch rate of yellow perch for example (Figure 7). Yellow Perch stocks declined in the early 1990 s (Ryan et al. 2003) but soon recovered. The commercial fishery responded with increased effort in both Ontario and Ohio (Figure 8). As a result the overall catch of yellow perch in the late 1990 s and early 2000 s also increased, (Figure 10 and Figure 7). Effort in the sports 14

15 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 15 of 40 fishing industry did not increase (Figure 8) and consequently there was no increase in harvest (Figure 7). The increased catch by the commercial industry (Figure 11) suggests that fish are available for harvest. This notion was tacitly reiterated by the fisheries management agencies through increased TACs. The sport fishing industry in Ohio has been enjoying catches almost as high as Ontario s commercial fishery and much better than any other state/provincial sport fishery. There has been an overall decline in effort by sport anglers to catch walleye since the late 1980 s and early 90 s (Figure 2). Despite this, catch per unit effort (CPUE) for walleye has recently risen as high as the peaks experienced in the 1980 s (Figure 6). This indicates that the status of the current sports fishery for walleye is excellent and considered high-quality. Despite arguments to the contrary from the Ohio charter-boat industry, the fishery appears to be as good, or better than it has ever been. Figure 11 and Figure 12, also shows that in 2005, walleye and yellow perch abundance returned to near historical levels, indicating that there are as just as many fish available to the sport fisheries as there have ever been. UNDER-EXPLOITATION Lake Erie fisheries are generally underexploited or moderately exploited depending on recruitment dynamics. Despite this, several species are underutilized including walleye, whitefish, yellow perch, white bass, white perch, smelt, freshwater drum, carp and catfish. In 2006 Ohio received 51.4% of the TAC for Lake Erie walleye for a total of million fish out of million fish (Lake Erie Committee 2006). Ohio received by far the largest portion of the TAC despite the fact that there is no commercial harvest of walleye. The Lake Erie Walleye Task Group (2006) reported that million walleye or about 61.6 % of the million 2005 TAC were harvested. They also noted that Ohio Sport anglers harvested 20 % of the state s TAC which was the lowest harvest since Angler effort again decreased as it has since 1988 to the lowest amount since 1976 (LEWTG 2006). Ohio has harvested significantly less than its TAC allocation since 1990 (LEWTG 2006), which equates to a potential loss of $3-$15 million a year. In Ontario, the commercial fishery is geared to harvest as much of their TAC allocation as possible by regularly monitoring commercial harvest. The result of this can be seen in Figure 3, where TAC and harvest are almost identical. In contrast, the harvest of walleye in Ohio has been significantly less than their TAC since 1990, see Figure 9. As previously discussed, this equates to a huge loss of potential revenue and employment opportunities. Figure 11 shows harvest of walleye relative to TAC and predicted lakewide abundances. It is clear from these data that many walleye are available for harvest in Lake Erie. The TAC for yellow perch was set at million pounds in 2005 and lakewide harvest was 9.7 million pounds. Ohio only filled 52 % of their quota in Management Unit 1 and 43 % in Management Unit 2 and Management Unit 3 of the central basin 15

16 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 16 of 40 (Lake Erie Yellow Perch Task Group 2006). At a modest $2/lb this equates to a potential revenue loss of $10 million landed value for yellow perch in Figure 12 shows harvest of yellow perch relative to TAC and predicted lakewide biomass. It is clear from these data that yellow perch are abundant and available for harvest in Lake Erie. For non-quota species, white bass generated almost $2 million in dockside value in Ontario and only $250,000 in Ohio in Whitefish and smelt are not target species for Ohio sports anglers but are worth close to $2 million a year to the Ontario commercial fishing industry (Kinnunen 2003). White perch, freshwater drum, channel catfish and carp collectively generated less than a half million dollars dockside in Ohio (Kinnunen 2003). These species are all non-quota and not generally pursued by sports anglers, suggesting that once again, Ohio is losing out on potential revenue generation. CAVEATS If walleye and/or yellow perch populations in Lake Erie crash, then even with reduced angler effort, the full share of Ohio s TAC could be harvested. Otherwise, a commercial fishery in Ohio will likely never exceed the TAC allocation. The ability for Ohio to harvest their total share of walleye and yellow perch is currently reduced due to lobbying and other political pressures. If fish stocks remain strong there will be a surplus of fish in Ohio waters of Lake Erie. The largest year classes of walleye and yellow perch ever recorded were in It is unlikely that license sales will spike as occurred in the late 1980 s due to reasons discussed in the section titled DEMOGRAPHIC TRENDS IN OHIO SPORT FISHERIES (i.e, excessive costs associated with fuel, excessive costs of insurance, lack of interest in sport angling in Lake Erie, perception that fish from Lake Erie are not healthy to consume, etc.). Despite this TAC allocations must be adhered to in order to ensure that the fishery remains sustainable. ABORIGINAL FISHERIES ON THE GREAT LAKES There has been a long standing conflict between aboriginal commercial fisheries and sport anglers despite the fact that several well managed native commercial fisheries exist within the Great Lakes (particularly Lake Michigan and Lake Huron). Lake Erie is the only Great Lake that does not have an aboriginal commercial fishery (Kinnunen 2003). In Canada, aboriginal fisheries are usually termed First Nations fisheries, while in the US, aboriginal fisheries are referred to as tribal fisheries. Several examples of well managed tribal commercial fisheries are revealed through an examination of the activities of CORA (Chippewa Ottawa Resource Authority). CORA works with federal and state agencies as well as the Chippewa Ottawa people to 16

17 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 17 of 40 maintain a viable commercial fishery in Lakes Michigan, Huron and Superior. During the 1970 s CORA and the Chippewa Ottawa, went to court to regain fishing rights in waters agreed to under a treaty signed in 1836, in which land rights were relinquished in order to maintain fishing rights in adjacent waters. CORA plays a key role in all areas concerning the fishery, including management, enhancement, law enforcement and monitoring environmental issues (CORA 2007). A second example of a tribal commercial fishery in the Great Lakes, is the Saugeen Ojibway fishery in the Ontario Waters of Lake Huron and Georgian Bay. In 1993 the Province of Ontario filed criminal charges against an aboriginal fisherman (Jones- Nadjiwon). Charges were dismissed by Judge David Fairgrieve on the grounds that both the sales ban imposed by Ontario and the Province s application for quota for aboriginal people were unconstitutional. He also ruled that the Saugeen Ojibway s exclusion from fisheries research and management was a major source of the many problems surrounding this case. His ruling re-affirmed treaty rights for the Saugeen Objibway to fish/trade or barter in their traditional waters. In 2000, the Chippewas of Nawash Unceded First Nation and the Saugeen First Nation came into an agreement with the Ontario Ministry of Natural Resources (OMNR) to coordinate fisheries management in these waters. A further agreement was signed in 2005 that gave the First Nations responsibility to designate community fishers and to monitor the commercial fishery through catch sampling. Both parties agreed to share all data collected and set safe harvest levels through a joint biotechnical committee. They also agreed that gill-nets would not be used near the town of Owen Sound and that certain areas would remain closed to commercial fishing during the month of August to avoid conflict with increased traffic due to a large fishing derby (OMNR 2005). Order of priorities of Great Lakes fisheries management are: 1) Conservation 2) First Nations, 3) Sport Fishery 4) Commercial fishery (Strategic Plan for Ontario Fisheries 2006). As such, conservation issues for SARA species such as sturgeon, lake herring supercede First Nations fishing rights as well as sport fishing and commercial fisheries quotas. Currently, there is not a single First Nation with official standing on the Great Lakes Fishery Commission, its Secretariat, Board of Technical Experts, Lake Committees, or the Lake Technical Committees which are responsible for basin-wide fisheries research and management planning (Saugeen Ojibway Nation Territories 2004). CONCLUSIONS There have been several fluctuations in abundance of percid species such as walleye and yellow perch since the early 1900s related to ecological perturbations in Lake Erie. Unregulated discharge of nutrients (largely from industrial and urban effluent containing high levels of phosphates from detergents and other sources) as well as unregulated overexploitation of several different species of fish resulted in dramatic declines in fish stocks from the 1950s to the 1970s. Ideal environmental conditions resulted in recruitment of two large year classes of walleye in the mid 1980s, 17

18 Case 3:05-cv JZ Document 90-2 Filed 06/29/2007 Page 18 of 40 coinciding with mass recruitment of the baby-boomer generation into the angling population. The sale of fishing licenses as well as sport angling effort soared in Lake Erie. By the mid 1980s, dreissenid mussels were firmly established in Lake Erie and these benthic organisms shifted the flow of large amounts of energy and nutrients from the pelagic food web to the benthic food web. These shifts in trophic dynamics were further exacerbated in the early 1990s by the invasion of round gobies. This adversely affected walleye and yellow perch until the late 1990s, and sport angler effort, especially in Ohio, began to decline. By the mid 1990s, water clarity increased penetration of sunlight, enhanced macrophytes growth and thereby increased the amount of available habitat despite reductions in lake level. Furthermore, dreissenid mussels and gobies became an increasingly important component of the diets of many fishes in the lake including walleye, yellow perch, smallmouth bass, freshwater drum etc. Abundance of burrowing mayflies (Hexagenia) has increased dramatically in recent years in response to reduced turbidity and reduced eutrophication. Hexagenia are a major component in the diet of yellow perch. In 2003, ideal environmental conditions produced the strongest walleye year class on record, as well as a very strong yellow perch year class. Despite this, sport angling effort is near an all time low and is the lowest it has been since the mid 1970s. TACs are carefully determined and fluctuate in response to index data indicative of actual abundance of fishes in Lake Erie. TACs are risk averse and designed to protect fish stocks. The majority of evidence indicates that the quota system and TACs have successfully limited the degree of overexploitation occurring in Lake Erie. Considering current patterns of fish abundance (Figure 11 and Figure 12) and reductions in sport angler effort (Figure 2), there is no reason to limit TAC allocations in Ohio to the sport fishery exclusively. The economic potential of underutilized species could be greatly enhanced through investment in value-added processing capabilities and development of a commercial market. There is the potential for significant revenue generation through increased commercial fishing without compromising the apparent value of the sport fishery in Lake Erie. As long as TACs are adhered to, it does not matter whether tribal enterprises or other commercial fishing operations harvest the fish. REFERENCES Bridgeman, T.B., Schloesser, D, and A.E. Krause Recruitment of Hexagenia mayfly nymphs in western Lake Erie linked to environmental variability. Ecological Applications. 16(2): Bunt, C.M., MacIsaac, H.J. and G. Sprules Pumping rates and projected filtering impacts of juvenile zebra mussels (Dreissena polymorpha) in western Lake Erie. Canadian Journal of Fisheries and Aquatic Aquatic Sciences. 50(5):