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Everyone tends to think of goldfish as these small innocent fish that everyone and their brother has as a pet when they are growing up but most do not know that when they are released into larger waterways that they grow to enormous sizes.  I recently read an article that highlights Cleveland Metro Parks and their battle against these goldfish in their waterways (Johnston, 2017).  The representatives from the Metro Parks speak about how these goldfish can be found all over their waterways and cause problems for native species.  This is accurate with the idea that non-native introduced species like these goldfish take away resources for the native species (Nico et al., 2013). The Cleveland Metro Parks are especially unhappy with the goldfish being there because they tend to take the resources away from the pan fish and catfish and they reproduce very quickly.  Metro parks uses electrofishers to stun and then capture the fish for removal which is a very selective removal technique meaning that it can be used to collect the goldfish and leave the other fish alone.

This whole situation is a prime example of what happens when people release their pets into native waterways.  They do not always become this invasive or detrimental to the other species but when they do it becomes something that could have been easily avoided.  The lesson to be learned from this situation is that you should never release your pets into the wild because you never know what effect they can have on the native species.

Sources:

1. Johnston, C. L. (2017, October 26). Monster goldfish: What happens when you release that little pet into the wild. Retrieved October 31, 2017, from http://www.cleveland.com/metro/index.ssf/2017/10/monster_goldfish_what_happens.html
2. Lennox, S. (2016, April 9). Giant Goldfish Are Invading Alberta Waters: Reports. Retrieved October 31, 2017, from http://www.ecanadanow.com/science/2016/04/09/giant-goldfish-are-invading-alberta-waters/ (Pictures)
3. Nico, L.G., P.J. Schofield, J. Larson, T.H. Makled, and A. Fusaro, Carassius auratus(Linnaeus, 1758): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=508, Revision Date: 8/2/2013, Access Date: 10/31/2017

The American eel (Anguilla rostrate) is a state threatened species of freshwater eel, and the only freshwater eel found in North America. These eels are found in any Ohio stream and in Lake Erie, but their home range covers most of the eastern United States. They are most normally found in large rivers with continuous flow. The American eel is a nocturnal species. They tend to hide in deep pools during the day and feed on aquatic invertebrates and fish at night. They are a prey species to larger fish, like bass, reptiles, some mammals, and fish-eating birds. 

Adults have a long, cylindrical snake-like body with a single dorsal fin running along their body. They have short, round pectoral fins on the side of their body and a mouth filled with very small teeth. These eels are very muscular and secrete a slime that creates a protective mucus layer around their body. Adult American eels can have a wide color range, most being brown with yellow on the sides. They will then turn a black and silver or bronze eel during their reproductive phase. Males can get about 18 inches long while females are larger, averaging about 36 inches.

The American eel is a catadromous species, meaning they spawn in saltwater but spend most of their lives in freshwater (Ohio DNR Division of Wildlife). Little is known about the spawning of the American eel, as no one has witnessed it. What we do know is that adult eels migrate downstream to the ocean by using what is thought to be the Earth’s magnetism and their homing abilities. These eels spawn only in the Sargasso Sea, a warm region of water located in the southeast of the Atlantic Ocean. These eels will spawn and then die. The females can lay up to about four million eggs, who, once hatched, are small transparent larvae who float on the ocean’s currents for about 12 months (The Nature Conservatory). The surviving eels will then migrate their way back towards North America and into freshwater. These baby eels will then travel upstream into rivers, estuaries, and bays, spending as much as 20 years in freshwater before beginning the life cycle over again.

The American eel populations have been on the decline. Dams and other human-made obstacles in the rivers have had the largest impact on their populations. These obstacles prevent the eel from migrating upstream or downstream, sometimes preventing populations from reaching the Sargasso Sea to spawn. These obstacles also cause habitat loss, putting stress on the eels from predators as they are a easy prey species (USFWS). American eels are also very susceptible to low water quality, meaning that habitat degradation has also negatively effected populations. These eels are harvested for food, and the overfishing of juveniles have added to the overall decline of this species. This makes it very important to conserve the American eel so these fish don’t become extinct. They are such a unique species, with their distinctive life cycle and that fact that they are the only freshwater eel in North America. American eels are a treasure to have in Ohio, so help protect their habitat so that future generations can enjoy them too.

 

References:

“American Eel.” Ohio DNR Division of Wildlife, ODNR Division of Wildlife, wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish/american-eel.

“Information About the American Eel.” The Nature Conservancy, www.nature.org/newsfeatures/specialfeatures/animals/fish/american-eel.xml.

“American Eel Videos, Photos and Facts.” Arkive, www.arkive.org/american-eel/anguilla-rostrata/.

USFWS Northeast Region Division of External Affairs. “The American Eel.” National USFWS Website, www.fws.gov/northeast/americaneel/.

 

Images (In Order of Appearance):

Photo by Minnesota Department of Natural Resources

Photo by Cornell University

Photo by Melisa Beveridge

Ohio’s Living Fossils

Sturgeon are a group of around twenty-five fish species that are in the family Acipenseridae. They are found all over the world, from Europe to Asia to right here in North America. In the United States, they are native to the Great Lakes, the St. Lawrence, Missouri, and Mississippi Rivers, and can be found on both the east and west coast and in the Gulf of Mexico. Interestingly enough, there are no known native populations of sturgeon that exist south of the Equator (Fishbase 2017). This group of fish has been found in the fossil record as early as 245 million years ago, making them the oldest of the ray-finned fishes. However, what makes them “living fossils” is that they have not evolved much in the last 240 million years; the sturgeons that exist today are very similar to the sturgeons that lived during the same time of the dinosaurs (Gardiner 1984). The image below shows a tree of the relationships between modern fish groups. The placement of the sturgeon in relation to the teleosts (which contains 96% of all modern fish diversity) demonstrates its status as a “relict” fish, a living fossil, along with the gar, bowfins, and birchirs.

Image taken from the lectures of Dr. Suzanne Gray, The Ohio State University

 

The Life of a Sturgeon

Sturgeon primarily are benthic feeders, which means that they feed on the bottom of rivers and lakes. They usually feed on snails and mussels, but have also been known to eat fish and plants (ODNR Lake 2012). To have babies, sturgeon move into rivers to spawn. When this happens, females can lay thousands of eggs at a time into the water column that are then fertilized by the males’ sperm. This process is called “broadcast spawning.” However, very few of these eggs to adulthood. The baby sturgeon are slow-growing and can take a long time to reach sexual maturity (20-25 years in the case of Ohio’s own lake sturgeon). Unlike salmon, sturgeon can spawn multiple times throughout their life, but do not spawn every year, sometimes going multiple years between spawning events (lake sturgeon typically spawn every four to seven years). While they may take a long time to mature, sturgeon are incredibly long-lived. Their average life-span is 60 years, but some species, like the lake sturgeon, can live longer than a century (ODNR Lake 2012).

 

Now that you know a little bit more about sturgeon in general, let’s take a look at the two species that call the waters of Ohio home:

Lake Sturgeon (Acipenser fulvescens)

Photo by the Tennessee Aquarium

 

The lake sturgeon is native to the waters of Lake Erie and the Ohio River, as well as in some of the larger inland rivers that feed into these water bodies. A large fish, this sturgeon measures 6-8 feet in length and usually weighs around 100 pounds (Trautman 1981). The largest specimen recorded was caught in 1929, weighing 216 pounds (ODNR Lake 2012) The Lake Sturgeon is “sharply bicolored” meaning that the dorsal (top) half of its body is one color (in this case olive-yellow, grey, or bluish), and its underside is a different color (in this case milky/yellow-white). These fish have a series of bony plates that run along their back and sides, forming ridges on their body. While these plates are sharp in juveniles, they dull as the sturgeon ages, becoming blunt by the time they reach adulthood (Trautman 1981).

Shovelnose Sturgeon (Scaphirhynchus platorynchus)

Photo by Ohio Division of Wildlife

 

The other native Ohio species of sturgeon, the shovelnose sturgeon, is the smallest sturgeon species in North America, reaching lengths of about 2.5 feet long and weighing usually 1-5 pounds. However, the largest specimen recorded in Ohio was 32 inches long and weighed 10 pounds. The shovelnose can be easily distinguished from the lake sturgeon by its wide, flat snout that gives this species its name. It also is bicolored like the lake sturgeon, but the shovelnose is usually brown, olive, or grey dorsally, and whitish underneath. The shovelnose has a long, thin caudal peduncle completely covered in bony plates, whereas the lake sturgeon’s is much wider and only has plates on the side. The bony plates covering the caudal peduncle are also sharp in both juveniles and adults, and do not dull over time like the Lake Sturgeon. In Ohio, the shovelnose sturgeon is native to the waters of the Ohio River and its tributaries, having also been caught in the Scioto and Muskingum Rivers (Trautman 1981). Interestingly, while lake sturgeons have been reportedly able to live to be 150 years old, shovelnose sturgeon live much shorter lives, rarely living past the age of 12, and spawn fewer times in their lifetime (ODNR Shovelnose 2012).

 

Conservation

While sturgeon are incredibly interesting as living fossils, populations of sturgeon species worldwide have been in decline. Both the lake sturgeon and shovelnose sturgeon are listed as “Endangered” in the state of Ohio. Information from the International Union for Conservation of Nature (IUCN) suggests that sturgeon are one of the most imperiled groups on the planet, with 85% of the species worldwide at risk for extinction (IUCN 2010). Two important human-induced factors leading to their declines are shown below: dams and caviar.

Left image from AS Food Studio, Right image from Popular Mechanics

 

While dams may be beneficial to us, they play havoc with a sturgeon’s life cycle. Many sturgeon species have migration routes and preferred spawning grounds. The construction of dams blocks a sturgeon’s ability to follow these routes or get to their spawning grounds, affecting their reproduction. Sturgeon are also harvested for their eggs, which are sold as caviar at high prices. In recent years, the market for this product has grown considerably, so more and more sturgeon have been harvested, both legally and illegally, to meet this demand (WWF 2017). Because it takes so long for sturgeon to reach maturity, and because they do not spawn every year, they are incredibly susceptible to overfishing, which has been shown in their species declines over the last few decades. Although they have been around for millions of years, unless action is taken to reduce sturgeon population declines, these living relics could potentially disappear into the fossil record for good.

 

Works Cited

Fishbase. 2016. Family: Acipenseridae. Fishbase. Online. Retrieved November 2^nd, 2017 from http://www.fishbase.us/identification/SpeciesList.php?famcode=32&areacode=&spines=&fins=.

IUCN. 2010. Sturgeon more critically endangered than any other group of species. IUCN. Online. Retrieved November 2^nd, 2017 from https://www.iucn.org/content/sturgeon-more-critically-endangered-any-other-group-species.

Gardiner, B.G. 1984. Sturgeons as living fossils. Pg. 148-152 in Living Fossils, Eldredge, N., and Stanley, S.M. Springer-Verlag, New York.

ODNR. 2012. Lake Sturgeon. ODNR Division of Wildlife. Online. Retrieved on November 2^nd, 2017 from http://wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish/lake-sturgeon.

ODNR. 2012. Shovelnose Sturgeon. ODNR Division of Wildlife. Online. Retrieved on November 2^nd, 2017 from http://wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish/lake-sturgeon.

Trautman, M.B. 1981. The Fishes of Ohio. Ohio State University Press, Columbus, OH.

WWF. 2017. Sturgeon. World Wildlife Foundation. Online. Retrieved November 2^nd, 2017 from http://wwf.panda.org/what_we_do/endangered_species/sturgeon/.

At approximately 9,940 square miles, Lake Erie is an incredibly important component of the Great Lakes¹. Whether it is due to the lake’s aesthetic value or its economic importance, Lake Erie is an ecosystem that is heavily monitored and researched. This monitoring has revealed a couple of very concerning trends that seem to be intensifying as a result of anthropogenic disruption and alteration.  Regardless of whether it is the well-known algae blooms caused by increasing levels of dissolved phosphorous finding its way to the lake from agricultural and urban management practices or the introduction of invasive species and their effects on native fish populations, humans are disrupting the natural ecosystem of the lake at concerning levels². One of the monitored aspects of the lake is the temperature of the water within the lake. Studies have shown that water temperatures have become warmer over the past 90 years⁶. Although the warming temperature is rather inconsistent in nature, resulting in up and downs in temperature on a year-to-year basis, linear trend lines indicate that water temperatures are getting warmer (refer to figure below). Water temperature readings are reaching all-time highs in the summer months and increased winter water temperature are resulting in decreasing ice cover⁴. Although a topic for debate, these increases in water temperature are largely a result of increased air temperatures resulting from climate change⁴. Understanding how these changes to the water temperature of Lake Erie may effect the organism within the lake is essential to future management and conservation strategies.

Short, Warm Winters Affect Successful Reproduction of Yellow Perch

The Lake Erie Yellow Perch (Perca flavescens) is a staple fish found in Lake Erie due to its relative importance ecologically, as well as, economically. With a harvest limit of 11.081 million pounds of total allowed catch in 2014, one can easily understand the importance of understanding the Yellow Perch physiological demands in order to best manage this species⁵. The Yellow Perch has a set of preferred reproductive traits and procedures that have proven essential to maintaining a healthy native population in Lake Erie. Female Yellow Perch develop ovaries in the cold winter months and spawn during the spring months³. With this in mind, studies have been conducted in order to understand how increases in water temperature resulting from warmer, shorter winters could affect the spawning success of this species. Results indicate that there are two main disruptions that arise from these shorter and warmer winter weather patterns. First, it seems that shorter and warmer winters are causing reduced size in Yellow Perch eggs, yielding smaller and less successful larvae³. In turn, this means that a reduced number of juvenile fish are advancing to the next life stage, potentially resulting in the reduction of overall surviving adult Yellow Perch in the lake. In addition, the spawning time of the Yellow Perch seems to be earlier than that of what it is typically seen under normal winter lake conditions. As seen in the figure below, spawning periods occurring around two weeks to a month earlier in shorter and warmer winter when compared to the typical longer and colder winters³. These unconventional spawning periods lead to increased food scarcity for surviving Yellow Perch juveniles, further impacting survival rates⁴. The study, run in an experimental setting and confirmed by actual lake conditions, show that the Yellow Perch is unable to adapt to the changing environmental conditions³.

 

Lake Erie Yellow Perch Population Dynamics & Impacts of Continuing Climate Change

            Research has confirmed that Yellow Perch are negatively impact by shorter and warmer winters resulting from climate change, therefore it is imperative to continue researching just how fast this species is able to adapt in order to avoid a drastic population crash. The figure below indicates that Ohio temperatures will continue to increase with the consequences occurring whether we decrease carbon emissions or not⁷. Since the Yellow Perch is such a prominent species within the seven-billion-dollar fishing industry in the Great Lakes, a decrease in the perch population or a potential behavioral response to move out of the warmer regions of the lake could have monumental consequences to regional economies⁴. In addition to Yellow Perch, further research as to how other species of fish may be impacted by these warming trends could inform conservation efforts for a wide range of operations, not just recreational and commercial fishing.      

References:

1. Lake Erie Facts and Figures. Retrieved November 1, 2017, from http://www.great-lakes.net/lakes/ref/eriefact.html

2. Michalak, Anna M. et al. “Record-Setting Algal Bloom in Lake Erie Caused by Agricultural and Meteorological Trends Consistent with Expected Future Conditions.” Proceedings of the National Academy of Sciences of the United States of America16 (2013): 6448–6452.

3. Farmer, T.M., Marschall, E.A., Dabrowski, K., Ludsin, S.A. (2015). Short winter threaten temperate fish populations. Nature Communications, 6 (7724)

4. Linn, M (2015, September 20) Climate change threatens perch, other warm-water fish. November 1, 2017, retrieved from http://greatlakesecho.org/2015/09/30/climate-change-threatens-perch-other-warm-water-fish/

5. Golowenski, D (2014, April 6) Lake Erie perch, walleye bag limits to stay same. Retrieved November 2, 2017, retrieved from http://www.dispatch.com/content/stories/sports/2014/04/06/lake-erie-perch-walleye-bag-limits-to-stay-same.html

6. Frankson, R., K. Kunkel, S. Champion and D. Easterling, 2017: Ohio State Summary. NOAA Technical Report NESDIS 149-OH,4 pp.

7. https://statesummaries.ncics.org/oh

Ohio has a variety of fish that have qualities that are considered ancient, retained from their ancestors, such as armored scales, jawless mouths, and a lack of paired fins. One such fish with ancient qualities is the Longnose Gar, in the Lepisosteidae family. A native Ohio fish, it has thick ganoid (diamond-shaped) scales that act like armor plating to protect them from other predators and an elongated, narrow snout full of sharp teeth. They look like the fish version of a crocodile and are just as deadly to their prey. They reach impressive sizes for a freshwater fish (the Ohio record is 25lbs and 49inches in length – Outdoor Writers of Ohio, 2017), and are terrifically successful ambush predators. With their heavy armor, they can’t sustain fast swimming besides a quick burst, so they lie in wait until small fish and minnows swim near and then they snatch them up with their formidable jaws. Their body coloration helps break up the shape of their body with the spots and blotches, similar to the way tigers and leopards use their coloration to their advantage in their habitats. They also display a type of coloration called countershading, which means they have a lighter stomach and a darker back. From below, the color of their stomach will allow them to blend in with the sky and from above, their back color allows them to blend into the substrate (Sea Grant 2013).  On another interesting note, Longnose Gar have poisonous roe (eggs). According to Burns & Stalling (1981), Longnose Gar roe shows negative effects on humans, lab mice, and domesticated animals. Their personal testing on natural predators of the roe showed it had a 77% mortality rate on crayfish (similar gar species had more or less of the same effect), but nothing noticeable happened to the bluegill that ate the roe. The crayfish that didn’t succumb to the poison still showed behavioral effects within 30 seconds to 4 minutes (depending on the species of gar roe eaten). The researchers noted that it made sense the crayfish were more susceptible since the timing of gar spawning coincided with peak crayfish young abundance. This would reduce the mortality of the gar spawn. Overall, this makes them deadly from egg to adult; truly an impressive species.

 

PHOTOS SOURCE

Lyons, J. (2013). Longnose Gar. University of Wisconsin Sea Grant Institute. Accessed November 2017 (http://www.seagrant.wisc.edu/home/Default.aspx?tabid=605&FishID=83)

 

REFERENCES

Burns, T. A., & Stalling, D. T. (February 16, 1981). Gar Ichthyootoxin: Its Effect on Crayfish, with Notes on Bluegill Sunfish. The Southwestern Naturalist, 25, 4, 513-515.

 

Outdoor Writers of Ohio State Record Fish Committee (2017). Current Ohio Record Fish. Outdoor Writers of Ohio. Accessed November 2017 (http://outdoorwritersofohio.org/ current-ohio-record-fish/).

 

University of Wisconsin Sea Grant Institute. (2013). Longnose Gar. Accessed November 2017 (http://www.seagrant.wisc.edu/home/Default.aspx?tabid=605&FishID=83)

The Blue Catfish (Ictalurus furcatus) is one of the largest native fish in North America, behind only the Alligator Gar and a few species of Sturgeon. This fish can grow up to 6 feet in length and 120 pounds in ideal situations! Although fish this size have not been found in Ohio, the state record is still a whopping 96 pounds. Within the buckeye state they are usually found in the deep, fast flowing waters Ohio river and its tributaries, hover this has changed in recent years. In 2011, the Ohio Department of Natural Resources decided to stock Blue Catfish to Hoover Reservoir in Westerville Ohio. This was attempt to expand their range and bring them to an area where they could become a fruitful fishery.  The fish were produced and raised at the Hebron and St. Mary’s state fish hatcheries. Aged one year and younger, the fish were released into Hoover with the hopes that it would become a fishing destination within the state.

Fast forward to 2017. The Blue Catfish stocking program was revaluated through a series of electrofishing surveys and the results were very promising. These samples have shown fish ranging in size from 4 inches up to 33 inches with the largest fish weighing 17 pounds. Although these fish have yet to reach the size of some found in the Ohio River, Hoover Reservoir is well on its way to become a sought after fishery producing trophy sized fish. With the amount of success the fish are having at Hoover, other stocking programs have been initiated, one at Clendening Reservoir and one at Seneca Reservoir. Thanks to the positive results of this pilot study, be sure to keep an eye out for Blue Catfish coming near you!

 

Sources:

http://wildlife.ohiodnr.gov/stay-informed/news-announcements/post/blue-catfish-project-moves-to-hoover-reservoire

http://wildlife.ohiodnr.gov/stay-informed/online-articles-amp-features/your-wild-ohio-angler/post/blue-catfish-stockings

http://wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish/blue-catfish

http://www.dispatch.com/article/20140824/SPORTS/308249929

http://wildlife.ohiodnr.gov/hooverreservoir

Western Mosquitofish, Gambusia affinis, is a member of the Poeciliidae family, which is a family comprised of live-bearing fish. They are one of the few freshwater fish to bear live young. Because of this, the young are able to feed like adults and increase their population quickly. They are a dull colored gray with small dark spots on their fins. Mosquitofish also have an upturned mouth and flattened head. They are rather small in size, females typically at 2-3 inches long, while males only 1-1.5 inches long (ODNR, 2017). They can be found in many ponds or slow flowing streams throughout Ohio, however they are not native to Ohio at all!

So, how did these little guys get here? Well, as their name suggests, they feed on mosquito larvae, as well as other small aquatic insect larvae. Mosquitofish are great eaters, consuming about 42-167% of their body weight every day! Because of this, they were thought to be a great pest control and alternative to insecticide for controlling mosquito populations (USGS, 2017). They were introduced to Ohio in 1947 in western Lucas County, but their region has since been expanded sporadically throughout the state (ODNR, 2017). As most non-native species introductions are, this was quite controversial.

Why may these teeny little fish be an issue? They may be small, but they are mighty! Also, as mentioned earlier, they can increase their population very fast. Mosquitofish have an extremely aggressive and predatory behavior. This makes them a threat to other small fish species through predation and competition. Mosquitofish populations may even displace native Ohio fish species, which is not good for the health of our streams. They have been found to be the reason for declines in several topminnow species, other fishes, invertebrates, and even amphibians throughout the continental United States. Recent introductions of Mosquitofish in New Zealand and the Hawaiian Islands reduced genetic diversity within the community (Purcell et al. 2012).

This invasive species causes more harm than good! It has been reported that Mosquitofish are not very effective in reducing mosquito populations. In fact, they may even benefit mosquitos by decreasing competition from zooplankton and reducing predation from other invertebrates (Blaustein and Karban 1990). Mosquitofish can also potentially cause algal blooms by feeding on an abundance of zooplankton grazers (Hurlbert et al. 1972).

Mosquitofish are only one example of a non-native species, including many plant species, introduced to Ohio to serve some purpose. It seems to be a game of chance whether the introduction causes harm or good. It is clear that research and much consideration should be taken before altering the environment in such a drastic way.

Check out other invasive Ohio fishes here (under the heading ‘Invasive Fish’): http://wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish

Bibliography:

Blaustein, L., and R. Karban. 1990. Indirect effects of the mosquitofish Gambusia affinis on the mosquito Culex tarsalis. Limnology and Oceanography 35(3):767-771

Hurlbert, S.H., J. Zedler, and D. Fairbanks. 1972. Ecosystem alteration by mosquitofish (Gambusia affinis) predation. Science 175:639-641.

Ohio Department of Natural Resources (ODNR). 2017. Western Mosquitofish. Retrieved from: http://wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish/mosquitofish

Purcell, K.M., N. Ling, and C.A. Stockwell. 2012. Evaluation of the introduction history and genetic diversity of a serially introduced fish population in New Zealand. Biological Invasions 14:2057-2065.

United States Geological Survey (USGS). 2017. Gambusia affinis. Retrieved from: https://nas.er.usgs.gov/queries/factsheet.aspx?SpeciesID=846

Photo credits:

• https://media1.britannica.com/eb-media/17/162017-004-55658173.jpg
• http://wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish/mosquitofish

Background

Migratory fish are species that move to accommodate their reproductive, feeding and refuge needs. Many fish migrate during only a small period of their lifetime. For several fish, migration takes place annually on a seasonal basis. Fish can migrate between marine and fresh water (diadromous fish) or between different fresh waters (potamodromous fish).

In the Great Lakes region, migrations are potamodromous and take on several different patterns. Some species, including Lake Sturgeon, Walleye, and Coaster Brook Trout migrate longitudinally from lakes to tributaries to spawn. Others migrate from lakes to coastal wetlands to spawn, like the Northern Pike. There are also species, such as the Lake Trout, that migrate from pelagic areas to near shore and off-shore spawning reefs. Not all migrations cover long distances, migrations by Great Lakes species range from 10s of meters to upwards of 200km. The following table summarizes a subset of Great Lakes migratory fish and their coarse migratory behaviors:

Common Name	Scientific Name	Most Commonly-Referenced Migratory Behavior
American eel	Anguilla rostrata	Between lake and river
Atlantic Salmon	Salmo salar	Between lake and river
Bluegill	Lepomis macrochirus	Within river
Brook Trout	Salvelinus fontinalis	Within river
Channel Catfish	Ictalurus punctatus	Within river
Lake Herring	Coregonus artedi	Between lake and river / within lake
Lake Sturgeon	Acipenser fulvescens	Between lake and river
Lake Trout	Salvelinus namaycush	Between lake and river / within lake
Lake Whitefish	Coregonus clupeaformis	Between lake and river / within lake
Longnose Sucker	Catostomus catostomus	Between lake and river
Northern Pike	Esox lucius	Between lake and river
Shorthead Redhorse	Moxostoma macrolepidotum	Between lake and river
Walleye	Sander vitreus	Between lake and river
Source: Great Lakes Inform: An Information Management & Delivery System, https://greatlakesinform.org/knowledge-network/758

Role in Great Lakes

Migratory fish play important structural and functional role in the Great Lakes. They influence the Great Lakes through direct and indirect mechanisms as consumers, ecosystem engineers, modulators of biological and chemical processes, and transport vectors (Flecker et al 2010). For example, species moving from one area to another move nutrients and energy between and among lake and riverine habitats. When fish or unfertilized eggs decompose, those nutrients are then available to the local foodweb.

Threats to Migratory Fish

• Tributary connectivity. Barriers that restrict upstream movement, such as dams and road crossings, can limit migration. If fish are unable to migrate to an ideal spawning habitat, they may be forced to spawn in sub-optimal conditions that result in reduced egg survival.
• Habitat degradation. Poor land-use practices in surrounding watersheds and pollution from urban or industrial sources contaminates migratory fish habitat.
• Invasive species. Invasive species stress migratory fish through competition and associated shifts in food web dynamics. They can prey on native fish and potentially out-compete native fish for food sources, resulting in sub-optimal diet for native fish.

Conservation Efforts

Several agencies are working to combat threats to migratory fish. These efforts include restoring tributary connectivity by removing dams, improving road crossings, and constructing fish passageways around barriers. Efforts also include restoring habitat by returning forest cover to riparian zones, recovering key native migratory fish species by stocking hatchery-reared fish and restricting harvest, and stopping the spread and controlling established invasive species.

Tracking Migratory Fish in Lake Erie

Tracking migratory patterns of fish is important for conservation efforts. The Great Lakes Fishery Commission established the Great Lakes Acoustic Telemetry Observation System (GLATOS) in 2010, with the goal of understanding fish behavior in relation to Great Lakes ecology and to provide useful information to fish managers. Acoustic telemetry is used to track fish movement. An acoustic tag that transmits a unique signal is implanted in the target species, and an acoustic receiver is used to decode the signal (Figure 1). Some transmitters can incorporate biological and environmental information such as pressure (to determine depth), temperature, and acceleration (to determine swimming behavior). Lake Erie migratory fish projects shared on GLATOS include studies of Lake Sturgeon, Muskellunge, Walleye, Grass Carp, Lake Trout, Sea Lamprey.

Figure 1: Acoustic tag and receiver. Source: http://glatos.glos.us/projects.

Case Study: Assessing adult Muskellunge movement in Buffalo Harbor, Lake Erie, and the Niagara River

Recently, Justin Brewer from the New York State Department of Environmental Conservation and the Niagara Musky Association partnered with the Habitat Enhancement and Restoration Fund to determine migratory patterns of muskellunge in Buffalo Harbor, Lake Erie, and the Niagara River. Knowledge of the seasonal use of these areas will help fishery managers better understand the habitat requirements of Muskellunge and will be used to direct habitat restoration projects. They are using the GLATOS array to document Muskellunge movement. Electro-fishing techniques were used to secure 10 viable musky samples from the Niagara River and Buffalo Harbor, 5 males and 5 females. Acoustic tags were surgically implanted into the musky and 6 acoustic receivers were planted to track them. These receivers are few of many that are updated to the GLATOS database, so if a musky is picked up outside of their study region, it will be detected. This is an ongoing study that will answer important questions about prime Muskellunge spawning habitat, viability, and whether it can be expanded.

References

Great Lakes Inform: An Information Management & Delivery System. Migratory Fish. Available at https://greatlakesinform.org/knowledge-network/758 (Last accessed 29 October 2017).

Great Lakes Acoustic Telemetry Observation System. Available at http://glatos.glos.us/ (Last accessed 29 October 2017).

The Buffalo News. Why this musky study is an investment in the future. Available at http://buffalonews.com/2017/06/14/musky-study-investment-future/ (Last accessed 29 October 2017).

Flecker AS, McIntyre PB, Moore JW, et al (2010) Migratory Fishes as Material and Process Subsidies in Riverine Ecosystems. American Fisheries Society Symposium 73:559–592.

Everyone knows that pollution is bad. We all do it to some extent, despite our efforts to minimize it. Often, we can get caught up in the mindset that a little bit of pollution or one littered item can’t hurt anything. However, this isn’t true. Scientists have discovered that even the smallest amounts of plastics in a fish’s habitat can cause major health problems (1). For instance, you drop a water bottle into the water from a boat. You’d think that this would have no effect on the fish that inhabit that water, but it does. Bits of plastic as small as half a millimeter can be eaten by small fish (1). In fact, fish tend to eat these bits quite often. They are unable to distinguish the difference between food and these bits of plastic. These pollutants not only affect adult fish but also prevent eggs from hatching, stunted growth, and increase their chances of being predated (1). These effects can cause major harm to not only an individual, but an entire population, community, and ecosystem. Populations can easily dwindle due to exposure to plastic. This can have a large effect on a community or ecosystem in many ways. For instance, if Northern Pike in Lake Erie prey on perch and the perch population is dwindling due to plastic, then the pike population can also begin to decline (2). This can then have an effect on other fish populations that are no longer predated by the pike, causing their population to soar and throwing the balance of the ecosystem out of whack. So next time you don’t care about that bottle falling out of a boat or you miss the trash can and don’t want to pick it up, think about the effect that you are having on our fish and their ecosystem!

Bibliography
1. Plastic cups found in fish. (1975). Marine Pollution Bulletin, 6(10), 148. doi:10.1016/0025-326x(75)90178-2
2. What do Northern Pike Eat? (2017, February 13). Retrieved September 26, 2017, from http://exc-adventures.com/what-do-northern-pike-eat/

Sturgeon-2eerk85

Lake Erie is a popular fishing spot due to the abundance of sport fishes that can be found in its nutrient rich waters.  Many fishermen and women flock to the shallowest of the Great Lakes every summer to see how many fish they can bring home for a tasty dinner.  Did you know that each year the Ohio EPA compiles a list of fishes in Ohio that they have observed to contain dangerous levels of pollutants like polychlorinated biphenyls (PCBs) and mercury (OEPA, 2017)?  These contaminants often enter waterways near disposal sites or near factories which use them for production.  Once PCBs and mercury enter a stream, river or lake, they bind with the sediment or disperse throughout the water column, where they are easily available for uptake by fish.  At this point, fish absorb or ingest the contaminants and because they do not easily dissolve, they are stored in the fish’s fatty tissues.  When predators like other fish (or people!) eat the affected fish, the fatty tissues within the predator absorbs the PCBs or mercury (James and Kleinow, 2014).   Watch the video below for a fun visual representation of this concept.  The brown shading represents the contaminants within the fish and you’ll notice that as each fish gets eaten, the consumer adds to the stores in their own fatty tissues.

Above video made by Krystal Pocock using iMovie for iPhone 7.

PCBs and mercury accumulate in fatty tissues and have a negative impact on human health (Hanrahan et al., 1997; Watras et al., 1995).   To prevent adverse health effects, the Ohio EPA makes recommendations as to the frequency and number of fish that are safe for consumption based on the average level of pollutant (e.g. mercury or PCBs) that a particular fish species has been found to contain.  In 2017, the biggest listed offender in Lake Erie was the common carp.  The OEPA recommends that individuals should only consume one common carp (over 27″) every two months.  For a list of other recommendations for common sport fishes (including Small Mouth Bass), please check out the 2017 Ohio EPA Fish Advisory Pamphlet.  If  you decide to consume any of the fish included on this list, the OEPA also recommends that you trim as much of the fat off of the fish as you can to potentially decrease the amount of the contaminants you’ll be consuming (OEPA 2017).  See the drawing below for an idea of where to trim the fat!

References:

Hanrahan, L. P., Falk, C., Anderson, H. A., Draheim, L., Kanarek, M. S., & Olson, J. (1999). Serum PCB and DDE Levels of Frequent Great Lakes Sport Fish Consumers—A First Look. Environmental Research, 80(2), S26–S37. https://doi.org/10.1006/enrs.1998.3914

James, M. O., & Kleinow, K. M. (2014). Seasonal influences on PCB retention and biotransformation in fish. Environmental Science and Pollution Research, 21(10), 6324–6333. https://doi.org/10.1007/s11356-013-1611-3

OEPA. (2017). Ohio Sport Fish Consumption Advisory. Retrieved from http://www.epa.state.oh.us/portals/35/fishadvisory/fishadvisory_pamphlet.pdf

Watras, C. J., Morrison, K. A., Host, J. S., & Bloom, N. S. (1995). Concentration of mercury species in relationship to other site-specific factors in the surface waters of northern Wisconsin lakes. Limnology and Oceanography, 40(3), 556–565. https://doi.org/10.4319/lo.1995.40.3.0556

 

Reel in the Culture

For the average Ohio angler, there’s nothing quite like spending a beautiful day casting your line out on Lake Erie and coming home to eat a delicious walleye or perch meal. The fishing tradition on Lake Erie has persisted for generations, with happy fishermen and women returning year after year to harvest the highly diverse fishing stock and enjoy the regional culture. But what happens if the quality of this fish stock were to suddenly be diminished? Would the strong fishing culture of the Lake Erie region be lost with it? This concern has become a little too real in recent years leaving many citizens and scientists alike very worried. Luckily, there are steps that you can take as an Ohio citizen, angler, or even just a lover of fish cuisine to ensure that the Great Lakes Region remains a fertile fishing ground for generations to come!

Are there really plenty of fish in the sea?

If you’re an angler targeting big sport fish such as walleye and perch in the Great Lakes, this can be a bit of a loaded question. Walleye populations have been preforming differently in different regions of Lake Erie, and yearly trends from the past few decades bring a lot of practices into question. Media sources from the more eastern regions of the lake report that Lake Erie’s sport fishing industry has a long and bright future ahead of it. Just this past summer angler reports from Buffalo, New York indicated a strong diversity of species within the fish stock as well as several juvenile walleye that will allow this sport stock to persist (The Buffalo News). However data collected from Lake Erie’s western basin shows slightly different and less optimistic results. Summer trawling surveys conducted in 2016 indicate that the population numbers for yellow perch are nearly average while walleye populations have fallen below their yearly average (ODNR). In an environment such as Lake Erie that historically has been known for its abundant fish populations, this may come as a surprise. Why aren’t these fish populations in the western basin performing as well as they used to?

Something’s Fishy

            It may seem odd that a fish population such as walleye can be successful in one section of a lake and declining in another. However, this trend starts to make sense when you consider the surrounding watersheds and characteristics of the eastern and western basins. While the eastern basin of Lake Erie is relatively deeper and a good portion of its natural surrounding watershed has been maintained, the western basin is very shallow and its watershed has become increasingly urbanized and agricultural. Suddenly the answer becomes very clear; algal blooms are the likely cause of these declines.

Harmful algal blooms (HAB’s) are defined as any large increase in algal density that is capable of producing harmful toxins. These HAB’s are caused when large amounts of phosphorous and fertilizers enter the lake through surface runoff such as during a big rainstorm (Ohio Sea Grant). These toxins are of major concern to people who recreate in Lake Erie and depend on it for drinking water. But they are also a major concern and threat to the many fish and aquatic organisms that call the lake home, and perch and walleye are not excluded from this threat. Not to mention that no one wants to consume a fish that has been living in a toxic environment.

What’s Happening to Our Fish?

When these HAB’s occur, the increased algal populations deplete the supply of oxygen that is dissolved in the water, which is necessary for fish survival. This low oxygen condition is known as hypoxia, and can result in massive fish kills where fish just start popping up dead. Fish rely on dissolved oxygen in the water to maintain their metabolic activity and overall energy. This being said, it is likely that a fish that can survive slight hypoxic conditions will still be under some stress and thus won’t grow or perform to its full potential. This can be highly unfavorable for anglers. Knowing all this, it can be assumed that these recent increases in the occurrence of HAB’s probably is playing a role in the declining fish stocks being observed in the western basin of Lake Erie.

How Can You Help?

All this information might come off as dismal and hopeless, but there are several ways to fight the occurrence of these HAB’s and make easy decisions to help our fish friends survive and thrive…

Reduce the amount of fertilizers entering the waterways

This practice can be as simple as using less fertilizer on your personal lawn or garden. Putting less fertilizer out on the landscape guarantees that less will be washed into the sewer and then into a nearby stream the next time it rains. You can also talk to your local politicians regarding fertilizer application laws to ensure that big agricultural operations are also following these rules. Everyone has a voice in their community and it should be used to lobby for solutions to wide-spread problems such as this.

Prevent surface runoff

Again this goes back to reducing the amount of pollutants entering the waterways. Planting shrubs, trees, and other plants can establish a solid root system that acts as a buffer on your property that will suck up excess fertilizer before it can make it into local waterways. Investing in a storm barrel to collect rainwater from your gutters is another easy solution.

Be kind to the environment

We all have heard the phrase ‘go green’, and now its time to do it. Simply making smart environmental decisions can help to reduce the urban stresses being placed on surrounding ecosystems such as water and air pollution. Reduce, reuse, and recycle; three simple actions to improve the state of Lake Erie and its many fishes.

Buy local and sustainable

As a consumer you have the power to vote with every dollar you spend at the super market. By supporting local and sustainable fisheries, you will ensure that your money is going to organizations that value fish conservation and sustaining fish stocks for the future.

While every Ohioan has their favorite spot to get a walleye sandwich, fishing is much more than just a way to get a meal. Fishing is essential to a region’s culture and can bring billions of dollars to the local economy through business and tourism. Fighting for the conservation of Lake Erie’s walleye industry is a fight for fish conservation and sustainability on the large scale, and luckily you can play a role in the persistence of this great Ohio pastime.

 

Sources:

“Algal Blooms in Lake Erie (North America).” Earth Watching , ESA, earth.esa.int/web/earth-watching/environmental-hazards/content/-/article/algal-blooms-in-lake-erie-north-america-.

“Free Family Fun in Lake Erie Shores & Islands: Eight Free, Fun Things to Do.” Lake Erie Shores and Islands , Lake Erie Shores & Islands, 26 July 2016, www.shoresandislands.com/blog/2016/07/26/free-family-fun-in-lake-erie-shores-islands-eight-free-fun-things-to-do.

Hilts, Bill. “Spreading the Good Word on Lake Erie Fishing.” The Buffalo News, The Buffalo News, 16 Aug. 2017, buffalonews.com/2017/08/16/spreading-good-word-lake-erie-fishing/.

“Initial Results of 2016 Lake Erie Walleye and Yellow Perch Hatches Released.” Wildlife News, ODNR Division of Wildlife , 28 Sept. 2016, wildlife.ohiodnr.gov/stay-informed/news-announcements/post/initial-results-of-2016-lake-erie-walleye-and-yellow-perch-hatches-released.

“Research in Focus – HAB’s .” Harmful Algal Blooms, Ohio Sea Grant , ohioseagrant.osu.edu/research/issues/habs).

Did you know that fish are one of the most popular pets in America? And of species of fish, Goldfish are the most popular (American Veterinary Medical Foundation). There is only one problem with having goldfish as pets; dumping them! Properly disposing of Goldfish, whether alive or dead, can cause issues for ponds, streams and lakes in Ohio. Goldfish are a non-native and invasive species of fish, meaning they are not from this area originally and pose many problems to other native species in Ohio (Beatty 2017). An established Goldfish population has already been established in Western Lake Erie and could inhabit bodies of water near you if they are not properly disposed of (Trautman 1981).

Dumping or flushing of live Goldfish into toilets or into bodies of water can directly introduce them to our streams and lakes. By doing so, a non-native species is added into the food web among native species. These invasive Goldfish can grow to massive sizes by taking food resources from native species of fish (Moyle 1976). They have also been found to eat the eggs of other native fish species even further so hurting their future populations (Moyle 1976). Goldfish also occupy habitats that native fish use for reproduction as well as shelter and are even able to reproduce with the Common Carp to produce larger, hybrid species that are equally as detrimental to native populations (Moyle 1976).

 

Dumping or flushing of live Goldfish can also be detrimental to bodies of water as these non-native species can introduce parasites and other diseases that our Ohio fish are not accustomed to (Washington Department of Fish and Wildlife). These fish, originally from Asia, as long as the water they live in inside tanks, carry potentially harmful diseases that we do not want shared with our native species of fish and if introduced, could spread these diseases!

As Lake Erie has already been affected by Goldfish, there is an even greater threat to highly sought-after game species of fish (Washington Department of Fish and Wildlife). Alongside this, there is also a threat to smaller bodies of water in Ohio that are currently unexposed to Goldfish. There have been cases in Colorado and other states where a few Goldfish in a small lake escalated to over 3,000 in just a few years (Block 2015). With Ohio having so many streams and other bodies of water, it is important that we keep Goldfish out of them, whether dead or alive to ensure the safety of our native species of fish.

In an NPR article, fish biologist Ben Swigle, recommends to humanly dispose of these fish. The method he suggests is to freeze the deceased fish overnight and dispose of it in the trash (Block 2015). There are also options to see if pet stores will take the fish back or pass on the fish to a new home.

No matter which option you choose, it is important that these highly desired pets are properly disposed of and do not end up in Ohio’s bodies of water as they have the potential to have long term effects on our native ecosystems and species. So, next time you or a friend goes to toss a Goldfish in a lake, think twice!

 

 

American Veterinary Medical Foundation. 2012 U.S Pet Ownership & Demographics Sourcebook. https://www.avma.org/KB/Resources/Statistics/Pages/Market-research-statistics-US-pet-ownership.aspx

Beatty, S. J., Allen, M. G., Whitty, J. M., Lymbery, A. J., Keleher, J. J., Tweedley, J. R., Morgan, D. L. (2017). First evidence of spawning migration by goldfish ( Carassius auratus ); implications for control of a globally invasive species. Ecology of Freshwater Fish, 26(3), 444-455. doi:10.1111/EFF.12288

Block, S. (Host) 2015, April 8. From Pet to Pest, Goldfish Tip Scales of Survival in Lake’s Ecoystem [Radio Broadcast episode]. http://www.npr.org/templates/transcript/transcript.php?storyId=398342023
Washington Department of Fish and Wildlife; Aquatic Invasive Species. Carassius auratus (Wild Goldfish). http://wdfw.wa.gov/ais/carassius_auratus/

Larimer, S. 2015, June 25. Discarded pet goldfish are multiplying. The Washington Post.

Moyle, P.B. 1976. Inland fishes of California. University of California Press, Berkeley, CA.

Trautman, M.B. 1981. The Fishes of Ohio. Ohio State University Press, Columbus, OH.

Addressing the issue of invasive sea lamprey within the Great Lakes ecosystems has always been complicated. According to Bryan et al., the introduction of the non-native species into Lake Erie was through the creation of the Welland Canal, which created an opening from the Atlantic Ocean to the Great Lakes in the early 1800s (2005)—however, the existence of sea lamprey was not considered a threat until the 1970s (Sullivan et al., 2003). It is due to the implementation of water protections policies, such as the Clean Water Act in 1972, and restoration of various game fish species during that time created an environment in which allowed sea lamprey populations to flourish where they could not before (Steeves et al., 2012).

While there are no formal policies regarding sea lamprey control, the Great Lakes Fishery Commission (GFLC) along with other informal interest groups, such as recreational anglers and commercial fisheries, have cooperated to address the detrimental presence of sea lamprey on the native wildlife of the Great Lakes. In recent years, the GLFC has begun to advocate for the reduced use of lampricide in favor of physical barriers, which have less of an effect on non-target species that may be sensitive to the chemicals; the downside of barriers is that they are easily swept away by flooding and rain, and are unable to cover wide areas (Bass Fishing, Sea Lamprey Control, n.d.). An alternative method recently approved by the U.S. Environment Protection Agency was the utilization of sea lamprey pheromones as a bio-pesticide dubbed “3kPZS”, its purpose being to attract sea lamprey toward traps (“Sea Lamprey Mating”, 2016), This proves to be an advantage to non-target species because unlike lampricides and physical barriers, which are either selectively applicable or run the risk of capturing or injuring non-target species, it involves the use of a “naturally-occurring, non-toxic chemical” that is specifically targeted for sea lamprey (Klein, 2016). Other methods such as sterile-male-release, in conjunction with the promising outlooks on 3kPZS, are directed toward sea lamprey explicitly and pose little harm to non-target organisms, which is a course of action that I recommend for sea lamprey control in the future.

Current popular methods of sea lamprey control, such as lampricides (a type of highly selective pesticide that target sea lamprey in the larval stage before becoming parasitic), several types of physical barriers that deter adult sea lamprey from reaching breeding grounds, in addition to various others have been highly effective in reducing the sea lamprey presence. The financial burden of maintaining and actively controlling sea lamprey populations, however, can be costly: in 2003, GLFC received $16,037,800 in federal funding from both the United States and Canada (Great Lakes Fishery Commission, n.d.); approximately $3 million of that budget alone was spent on registered-use pesticides (Kinnunen, 2015). The reason why I would advise pushing for strictly sea lamprey-targeted methods of control is due to the non-discriminatory nature of lampricides, barriers, and traps: there is the possibility of capturing federally protected species under protection policy, and thus the actions of the GLFC and other groups need to be closely monitored by the EPA to not cause harm to listed species that may co-inhabit ecosystems with the sea lamprey (Sullivan et al., 2003; Steeves et al., 2012). The use of lampricides has already decreased, and so further steps should be taken to minimize its use as much as possible and focus more efforts onto individual-type methods like sterile-male-release and pheromone manipulation.

Previously addressed, there have been severe conservations about the continued use of lampricide, as lampricides are cost-intensive (Lavis et al., 2003) and its effect on nontarget organisms, raising the concern of environmental protection policies such as EPA and NEPA, which requires agencies to review their methodologies and make sure that they align with the interests of species protection laws. In the past, lampricides have been a great success in reducing the sea lamprey population in Lake Erie to just 10% of its original numbers (Lavis et al., 2003); however, the long-term negative effects have driven the GLFC to pursue alternative methods. One idea that has been minimally tested thus far is the utilization of pheromones to attract sea lamprey to traps, confuse their migration patterns, and further prevent spawning (Steeves et al., 2012; Christie & Goddard, 2003). The most popular alternative method of sea lamprey control, arguably, would be the erection of physical barriers to prevent adult sea lamprey from accessing spawning habitats, and has proven to be the most successful method, other than lampricide (Sullivan et al., 2003). The general public’s perception of using chemicals to treat Lake Erie’s sea lamprey invasion have further supported the idea of reducing the use of lampricide even further (Lavis et al., 2003). Steeves et al. (2012) additionally addresses conflicts that arise from using lampricides during the same time as angler fishers would like to fish game, and in several areas where Lake Erie opens its waters for public consumption may bring forth negative connotations.

Several advantages of the proposed method of constructing more barriers than investing financial resources in lampricide are that building barriers are more affordable and requires relatively little of the sea lamprey control program’s budget, plus barriers have minimal effect on non-target organisms within the same areas of interest of the sea lamprey, falling into compliance with species protection policies (Lavis et al., 2003). Another benefit would most likely be an improved public perception of the sea lamprey control program. A disadvantage of shifting attention from lampricide to barriers would be the intensification of knowledge of sea lamprey migration patterns and places of interest such as sea lamprey-heavy streams within which barriers would most effectively be used (Lavis et al., 2003). The minimally tested method of manipulating sea lamprey with pheromones may yield negative consequences regarding non-target organisms, but has yet to be researched thoroughly; the fiscal requirements of this alternative method have also not been released, and so this may pose an economic dilemma in the future.

References

Bryan, M. B., Zalinski, D., Filcek, K. B., Libants, S., Li, W., & Scribner, K. T. (2005). Patterns of invasion and colonization of the sea lamprey in North America as revealed by microsatellite genotypes. Molecular Ecology, 14(12), 3757-3773.

Great Lakes Fishery Commission. (n.d.). Sea lamprey control in the Great Lakes. Retrieved from http://www.glfc.org/aboutus/budget.php#pr

Kinnunen, R. E. (2015). Sea lamprey control in the Great Lakes. Michigan State University Extension. Retrieved from http://msue.anr.msu.edu/news/sea_lamprey_control_in_the_great_lakes

Klein, K. (2016). So long suckers! Sex pheromone may combat destructive lampreys. Science. Retrieved from http://www.sciencemag.org/news/2016/01/so-long-suckers-sex-pheromone-may-combat-destructive-lampreys

n.a. (2016). Sea lamprey mating pheromone registered by U.S. Environmental Protection Agency as first vertebrate pheromone biopesticide. U.S. Geological Survey. Retrieved from https://www.usgs.gov/news/sea-lamprey-mating-pheromone-registered-us-environmental-protection-agency-first-vertebrate

n.a. (2016). Sea lamprey: The battle continues. Regents of the University of Minnesota. Retrieved from http://www.seagrant.umn.edu/ais/sealamprey_battle

n.a. (Writer), & n.a. (Director). (n.d.). Bass Fishing, Sea Lamprey Control [Television series episode]. In J. Merone (Producer), Outdoor Journal. Colchester, VT: Vermont PBS. Retrieved from http://www.vpt.org/show/11244/1003

Steeves, M., Mullet, K., Slade, J., & Sullivan, P. (2012). Lake-level, five-year plans for achieving sea lamprey control targets in each Great Lake. Great Lakes Fishery Commission. Retrieved from http://www.glfc.org/pubs/SpecialPubs/LL_5YearPlan.pdf

Sullivan, W. P., Christie, G. C., Cornelius, F. C., Fodale, M. F., Johnson, D. A., Koonce, J. F., … Ryan, P. A. (2003). The sea lamprey in Lake Erie: A case history. Journal of Great Lakes Research, 29, 615-626.

Last summer, I touched a fish for the first time since I was a little girl. Not only did I touch it, but I was in charge of getting it off the hook. (!!!) I looked down at the little girl holding her rod and fish, looking up at me expectantly, waiting for me to take it off the hook, just as my dad had done for me when I was a little girl. So, thinking back to my younger days, I thought I could just grab the fish and wriggle it around a little bit and it’d come off the hook. So I grabbed the fish and wriggled it around. I got it off the hook!! Then, to my dismay, it flopped around, in my hand ended up pricking me, and I jumped back and dropped it. (I learned later it was a Rock Bass-a spiny little fellow!) I didn’t know what to do. I started freaking out because I didn’t know how long it could be on the ground flopping around, and I didn’t want to grab it again because THAT HURT MY HAND.

So where was I and why was I “teaching” this little girl how to fish? I was at Stone Laboratory on Lake Erie in Ohio, and this was my summer job. It was apparently assumed the student workers knew what they were doing, but I certainly did not. SO…here I was, with a fish flopping around on the ground, with no idea what to do. I started screaming for another one of the student workers to come over and help. Thankfully, my fellow coworker knew what she was doing: crisis averted.

FAST FORWARD ONE YEAR: Fish are now my friend! And I now think they are really cool.

I have since learned a great deal about not only how to handle fish, but so much more. This summer, I had another job that involved fish. Fish were a part of just about everyday, and I learned to love them. Now, any time I walk by water, and see tiny fish darting around, I want to know what it is!

I’m also taking classes about fish at the Ohio State University, where we learn all sorts of fun stuff about fish. Did you know that freshwater fish comprise 30% of all vertebrate species, even though available freshwater habitat makes up less than 1% of the Earth? Crazy!!

Some other cool stuff we are learning are the major groups of fish, how these fish evolved, the morphology and anatomy, how to ID Ohio fish, morphological and behavioral adaptions, how humans effect fish, and so much more!

So here are some of the coolest things I’ve learned about fish this year, and things I would have loved to know last year:

• There are 181 species of fish just in Ohio! (154 native) Listed below are the species of Ohio.

 

 

 

 

 

 

 

 

 

• Lake Erie contains only ~2% of the water of the Great Lakes, but supports ~50% of the fish diversity of the Great Lakes. Conversely, Lake Superior contains ~50% of the water of the Great Lakes, but only 2% of fish diversity.
• Lake Erie tends to be much more productive (more life!) because of how shallow and far south it is compared to the other lakes, (meaning it stays warmer and more supportive of life). It is also surrounded by more farms and human residential areas (meaning more nutrients are coming off the land into the water) compared to other lakes, like Superior, which is largely surrounded by forest (meaning less nutrients). These nutrients cause the growth of things at the bottom of the food chain, such as algae and phytoplankton, which fish eat!
• Lake Erie is SOOO shallow! At it’s deepest it is only 210 feet. Lake Erie’s western basin (about 1/5 of the lake) is usually less than 25 feet. This is why the lake is so warm and productive! Look below to see how shallow Lake Erie is compared to the other Great Lakes!

• Humans have such a major impact on fish. I never realized how much humans could impact fish and water ecosystems until recently. That new parking lot they’re building down the street? The waterfront apartment building on the river? It affects the fish! But how?

Fish lives in all types of water throughout Ohio. Whether it’s a stream or a pond or a lake, humans have major impacts on fish ecosystems. Impermeable surfaces (parking lots, a sidewalk, a highway, or a building rooftop,) can raise the temperature of streams. When rainwater lands on an impermeable surface, it is warmed by sunlight. Heat is dissipated from the asphalt in the water, which is directed off the surface rather quickly, via a drain or gutter, and is funneled into urban streams, resulting in higher stream temperatures.

When humans build near water, it also decreases shade on the river, increasing river temperature. When trees are taken down, for a better view or for a waterfront apartment building, it opens the water up to direct sunlight, and an increase in stream temperature.

These increases in impervious surface area and reduction of tree buffer zones along streams, as well as other modifications to stream hydrology, impact the conditions in streams. This is known as “urban stream syndrome”. Unnatural spikes in water temperatures are seen in urbanized areas after rainfall. And these water temperature changes can have wide-ranging impacts on fish.

These increases and spikes in stream temperature can have big impacts on the fish that can inhabit the area, as certain fish can only survive within certain temperature ranges. If the temperature spikes too much throughout the day or during rainfall events, it has the potential to stress out the fish, causing issues or even death.

I’m doing research on the stress response of fish to these thermal shifts in streams caused by urbanization, and I am excited to see the results. My lab at Ohio State will be putting fish into tanks and raising and lowering the temperature throughout the day over a period of several weeks, and then testing the stress response of these fish at the end of the treatment. I’m thrilled to be doing work in such a cool field. I think it’s important that we learn how to take care of our aquatic friends as well!

Ironically, the other day while out in a stream doing fieldwork, we found another Rock Bass! (The fish from the beginning of this blog post.) It was the first Rock Bass I had seen since the one that had freaked me out so much last summer. It made me think about what a full circle I had come. It is my hope that you have picked up a thing or two about fish, and hopefully are not as clueless as I was about fish last year! Fish are incredible, and the more I come to learn about them, the more I appreciate what a diverse and amazing species they are.

 

 

 

Sources:

• Lake Erie cross sectional picture:
  • Michigan Sea Grant
• Ohio fish species list
  • ODNR
• Fish facts:
  • Eugene Braig’s and Suzanne Gray’s class lecture slides
• Other fish facts:
  • Herb et al. 2008
  • Sabouri et al. 2013
  • Klein 1979
  • Wang & Kanehl 2004
  • Walsh et al. 2005

 

SEA LAMPREY, SCOURGE OF THE GREAT LAKES

SEA LAMPREY 101

Sea lampreys (Petromyzon marinus) are an eel like fish prevalent in the Atlantic ocean, but have since become an invasive nuisance in the Great Lakes. The lamprey order, Petromyzontiformes, is an ancient one having lasted for 340 million years, surviving four major mass extinction events (GLFC, 2016). Sea lampreys are a fish parasite and have a long tubular body composed of cartilage a large sucker like mouth filled with teeth. They are the largest and most predacious of all their family, using their sucker to cling to a fish and teeth to penetrate the fish’s tissue. Once ruptured, the raspy tongue pulls scales away as their saliva secretes an anticoagulant to prevent the blood from clotting. After feeding, the fish is left with a hole in its tissue prone to infection (IDNR, 2017).

Left: Sea Lamprey mouth (NCRAIS, 2017).

Right: Lampreys attached to a trout (GLI, 2017).

 

WHAT IS THEIR LIFE CYCLE?

Larval lampreys hatch from eggs buried in the substrate of inland streams. Once they hatch, the current carries them further down stream until they burrow into the silt. Once planted they remain in this stage for about 4-6 years as bottom feeders, eating algae and other organic material. After this stage, the adult parasites leave and move out to sea or other open water to feed on fish. After a period of 12-20 months, they return into the tributaries to spawn and die (GLFC, 2016).

Right: Sea Lamprey life cycle (GLI, 2017).

HOW DID THEY ENTER?

Most researchers speculate the lamprey gained entrance to the Great Lakes area by means of man made locks in shipping canals. Niagara Falls blocked the lampreys entrance, but with the construction of the Welland Canal and its refurbishment in 1919, lampreys had a path around the natural barrier Niagara Falls presented, gaining a new source of open water to expand. New populations were first noted in Lake Erie in 1921, spreading into all the rest in just 25 years (IDNR, 2017).

WHY ARE THEY SIGNIFICANT?

In the Atlantic, the lamprey’s targets have co-evolved so that their parasitism does not kill the host. This is not the case in the Great Lakes, where lamprey attack any fish and kill 6 out of every 7 hosts (GLFC, 2016). If a host fish does not die of blood loss, the open wound usually becomes infected causing mortality. The high mortality rates of lamprey hosts in the Great Lakes has lead to serious financial harm in the fisheries economy. Lampreys will feed on almost any fish in the lakes and the high mortality has caused significant population collapses. For instance, lake trout, whitefish and chub populations declined to extirpation in the 1940’s and 1950’s from lamprey predation. Given that a single lamprey is capable of killing over 40 pounds of fish within its lifespan, their pressure continues to affect the lakes today (GLFC, 2017).

HOW DOES THAT AFFECT ME?

Over the decades lamprey populations have grown in size and impact. For instance, the US and Canada used to collect around 15 million pounds of lake trout a year, but this number was reduced to 300,000 pounds a year in the 1960’s. This lack of product forced many out of a job in an industry that was shrinking (GLI, 2017). Currently, the government has managed the populations and advance of sea lampreys costing $14 million annually for conservation. If these efforts were to cease, the losses would be over $500 million a year in the fisheries economy (NCRAIS, 2017). There are close to 6,000 tributaries in the Great Lakes, and at least 433 of them have sea lampreys, and 250 are treated. The methods used include dispersing lampricide, installing low head dams and setting traps. All of which cost money a portion of which is subsidized by taxes (GLI, 2017).

 

Left: Lowhead dam (GLI, 2017).

Right: Lampricide application (GLI, 2017).

 

SO WHAT?

Invasive Sea Lampreys are causing a lot of problems in the lake biota, that has environmental and economical impacts. The cost to mitigate their damage, and conserve the natural species in part comes out of the tax payer’s pocket, showing that lampreys are a nuisance affecting everyone, even those who do not interact with the Great Lakes.

REFERENCES

Great Lakes Fishery Commission (GLFC). Great Lakes Fishery Commission – Sea Lamprey. 2017 [accessed 2017 Sep 28]. http://www.glfc.org/sea-lamprey.php

Great Lakes Fishery Commission (GLFC). Sea Lamprey a Great Lakes Invader. 2016 [accessed 2017 Sep 28]. http://www.glfc.org/pubs/FACT_3.pdf

Great Lakes Inform (GLI). Sea lamprey (Petromyzon marinus). Great Lakes Inform. 2017 [accessed 2017 Oct 1]. https://greatlakesinform.org/knowledge-network/1077

Indiana Department of Natural Resources (IDNR). Sea Lamprey. Aquatic Invasive Species. [accessed 2017 Oct 1]. http://www.in.gov/dnr/files/SEA_LAMPREY1.pdf

Michigan Department of Natural Resources (MDNR). Michigan Invasive Species. [accessed 2017 Oct 1]. http://www.michigan.gov/invasives/0,5664,7-324-68002_73845-374989–,00.htmloutput–1edq1f5   

NOAA Great Lakes Environmental Research Laboratory. NOAA National Center for Research on Aquatic Invasive Species (NCRAIS). Nonindigenous Aquatic Species. [accessed 2017 Oct 1]. https://nas.er.usgs.gov/queries/greatlakes/FactSheet.aspxSpeciesID=836&Potential=N&Type=0

In 1943, Ohio ichthyologist Milton Trautman made a rare discovery in a small riffle  in Big Darby Creek.  While seining along the downstream edge of a small riffle, he caught two madtoms that until that day, had never been described.  Today, the rare fish is known as the Scioto madtom (Noturus trautmani).  In total, four specimens were found between 1943-1945, all in the same stream section of the Big Darby Creek in a series of four riffles.  The area was searched extensively for a period of years in hopes of finding more of the rare madtoms, but no luck was had for over a decade.

In 1957, a glimmer of hope appeared.  Specifically, it appeared in the form of 14 Scioto madtoms, all caught between September and December of that year, and in the same riffle where the discovery had been made 14 years prior.  This hope was misplaced, however, as not a single Scioto madtom has been seen since, leading to the species being declared officially extinct in the early 2000’s.  As Trautman says in his book, Fishes of Ohio, “Since 1924 no stream section in Ohio has been seined more assiduously and intensely than have these riffles, and few species of Ohio fishes have been more consistently sought after than this one.”

Initially, several explanations were put forth to explain the difficulty in finding more organisms.  Today, it’s widely accepted that the rare catfish species known to be unique to the Scioto watershed is now extinct, likely as a result of habitat changes from a growing agricultural industry.  But at the time of the Scioto madtom’s discovery and subsequent loss, water quality was at a low-point in the United States.

A lot has changed since the last sighting of Noturus trautmani, including the passing of the Clean Water Act and creation of the EPA.  Water quality seems to have recovered in Ohio over the past 50 years, evidenced as recently as last week when students from Ohio Dominican University uncovered tippecanoe darters in Alum Creek.  The Big Darby Creek, where the Scioto madtom once thrived and was eventually lost, now has a near-perfect QHEI rating from the state EPA.  In these ways, the ghost of the Scioto madtom lives on through environmental legislation and education, saving species who otherwise may suffer a similar fate.

• Trautman, M. B. (1981). The fishes of Ohio: With illustrated keys. Columbus: Ohio State University Press.

New methods of DNA screening are allowing for detection of invasive fish species in the bait trade and outreach to anglers may help to stop the spread of invasive species into Ohio and the Great Lakes region.

An invasive species is one that has moved into an area it is not native to and damages the environment and organisms that are already established. Invasive species can drive native species out and the damage done can often be economic as well as environmental. Some Aquatic Invasive Species (AIS) already have a significant presence in Ohio, such as Zebra Mussel, White Perch, and Round Goby. There are two species of Asian Carp, Silver Carp and Bighead Carp, that are of particular concern to Ohio wildlife managers. While not yet established in the Great Lakes, Asian Carp are abundant in the Mississippi and Illinois, through which they pose a serious threat of invasion (Nathan et al. 2015). These voracious carp have the potential to decimate an ecosystem, and the Silver Carp can even jump out of the water and strike fisherman (http://ohiodnr.gov/asiancarp).

Silver Carp jumping out of the water in the Illinois River

Photo by Nerissa Michaels, Illinois Natural History Survey

 

Invasive species can be introduced to an ecosystem in a number of different ways. Ballast water from ships, the exotic pet trade, and even habitat managers purposefully introducing a non-native species are sources of AIS. One invasive pathway many people may inadvertently contribute to, is the bait trade. When anglers buy live bait it may contain other invasive species that can be released into the ecosystem.   White Perch, Tubenose Goby, and Ghost Shiner are some examples of established non-native fish in the Great Lakes that are used as baitfish. Baitfish are sometimes sourced from other regions of the country where other AIS are and may result in movement of AIS to new parts of the country (Nathan et al. 2015). To help track the threat of AIS, DNA test have been conducted to track the prevalence of infected baitfish stocks across the region.

Instead of visually searching every bait store for individual organisms, Environmental DNA Surveillance can be used to passively determine if a baitfish supply is infected with AIS. Environmental DNA (eDNA) Surveillance is a method where small strands of DNA are extracted from a water sample, in this case water taken from bait stores. These bits of DNA are not pulled directly from an organism, but rather have been excreted or left behind in the water. These small samples are amplified in a lab using a process called Polymerase Chain Reaction. The amplified strands are then checked against a database of known samples to identify what species of fish were present in the water sampled (Nathan et al. 2015, Mahon et al. 2014).

One study looked at 576 eDNA samples taken from 525 bait shops across all 8 states bordering the Great Lakes. AIS DNA was detected 27 times, including three instances of Silver Carp along the coast of Lake Erie in Ohio (Nathan et al. 2015). Similar studies have also detected White Perch, another species whose sale and possession is banned in a number of Great Lakes states (Mahon et al. 2014). Closing this pathway of invasion poses some challenges though.

Ohio Department of Natural Resources, Division of Wildlife. QuickID Features for Baitfish [Digital image from Powerpoint presentation]. Retrieved from http://ohiodnr.gov/Portals/0/pdfs/invasives/Pub%205487-D_Baitfish%20ID_WEB.pdf

 

Bait sellers are very often unaware of the species of baitfish they are selling, let alone whether it is invasive or not.  And anglers often don’t know that throwing unused bait fish in the trash and not the water is the preferred method of disposal (Nathan et al. 2014).

Preventing the spread of AIS through baitfish is further complicated since many states have different laws as to what constitutes legal baitfish. The issue crosses international borders as well. The Threespine Stickleback is listed as an invasive but is allowed in Ontario (Nathan et al. 2014). Efforts are underway to inform fisherman and bait sellers of the potential for introduction of AIS into the Great Lakes through baitfish (http://ohiodnr.gov/invasive-species/aquatic-invasives/bait-trade). Any sightings of Asian Carp in Ohio can be reported at http://ohiodnr.gov/asiancarp. Further outreach to anglers, consolidation of bait laws and potential regulation of the bait industry may be needed to seal up another avenue through which AIS can enter and devastate ecosystems.

 

 

Text Citations

Mahon, A. R., Nathan, L. R., & Jerde, C. L. (September 01, 2014). Meta-genomic surveillance of invasive species in the bait trade. Conservation Genetics Resources, 6, 3, 563-567. https://doi-org.proxy.lib.ohio-state.edu/10.1007/s12686-014-0213-9

Nathan, L. R., Mahon, A. R., Jerde, C. L., & McVeigh, M. (January 01, 2014). An assessment of angler education and bait trade regulations to prevent invasive species introductions in the Laurentian Great Lakes. Management of Biological Invasions, 5, 4, 319-326. doi: http://dx.doi.org/10.3391/mbi.2014.5.4.02

Nathan, L. R., Jerde, C. L., Budny, M. L., & Mahon, A. R. (April 01, 2015). The use of environmental DNA in invasive species surveillance of the Great Lakes commercial bait trade. Conservation Biology, 29, 2, 430-439. doi:10.1111/cobi.12381

http://ohiodnr.gov/invasive-species/aquatic-invasives/bait-trade

http://ohiodnr.gov/asiancarp