Do you know what’s in your fish? It sounds like a weird question since most people just think it is just fish. For the most part, we buy it and eat it, not considering where it comes from or what harmful chemicals may be in the meat. For many Ohioans who live around Lake Erie, catching fresh fish or eating fish from the lake is common and enjoyed by many. However, pollution from the surrounding infrastructure has been allowing chemicals into the lake. One of these chemicals is mercury.
What is Mercury?
Mercury is a naturally occurring element that is used in thermometers and industrial practices. It is toxic to humans and wildlife if ingested or the fumes inhaled. If a person or animal is exposed to enough mercury, it can damage the nervous system and can cause birth defects or infertility. Once the element enters the water, filter feeders such as clams and mussels filter it out of the water. The feeders are in turn eaten, passing along the mercury up the food chain. This process is repeated until it reaches the fish that are popularly consumed by humans.
In regards to fish caught and eaten from Lake Erie, the Ohio Environmental Protection Agency maintains a consumption advisory list for the state of Ohio. According to their list, Some fish, such as Yellow Perch and sunfish, are safe to eat for multiple meals a week. Other fish, such as Steelhead and Walleye, should only be consumed once a month due to their high mercury levels. For more information on fish that are safe and the recommended consumption levels, visit the Ohio EPA at the following link: http://epa.ohio.gov/dsw/fishadvisory/index.aspx#145214734-statewide
Spending a day near Lake Erie can be a refreshing experience from the breeze to the small towns along
route 6, and is best finished off with a perch sandwich. You sit down on a dock and your food arrives, but what you may not realize is that the breaded filet may not be native yellow perch, but invasive white perch instead! Although the meat on the sandwich may taste quite similar regardless of species, White Perch are a considerable problem in Lake Erie.
White Perch (scientific name Morone americana image from ODNR 2012) is a species of fish that is part of the temperate basses family, originating from the Atlantic coast. These fish usually live in waters that are a mix of salt water and fresh water, also known as being brackish. Despite originally being from the coast ranging from South Carolina to Maine, they have fully established themselves in Lake Erie (see map, taken from USGS 2017). The largest issue with white perch is that they will eat the eggs of many natives Walleye.
It is also theorized that White Perch compete with the native Yellow Perch for microscopic food sources known as zooplankton. Overall, since the invasion of White Perch into the Lake Erie basin, growth rates of Yellow Perch have declined, especially in the western basin where fishing for them is most prevalent (USGS 2017). When White Perch have made their way into inland reservoirs such as LaDue, East Fork, and Sippo Lake, they will spawn quickly and over populate the area (ODNR 2012). This leads to a condition known as stunting where fish grow very slowly due to a lack of resources. This can be concerning for managers because the large amount of small fish are neither fun to fish for nor easy to get rid of.
With a trend towards warmer winters due to climate change, there will be even more dramatic effects from the white perch. In an interview with Cleveland News, Dr. Ludsin from Ohio State said, “warmers winters benefit White Perch, which are sensitive to cold temperatures.”(Egan 2013). This has a lead to an increase in White Perch numbers and therefore increased predation upon yellow perch. To help combat the problem, there a some things that the public can do. Looking to the future it is unlikely that the white perch population will ever be removed from Lake Erie, but it’s effects will continue to be monitored and fish will still be taken to create a companion for tartar sauce.
Egan, D’Arcy. “Changing Lake Erie, invasie white perch threaten popular yellow perch in Western Lake Erie.” March 29, 2013. http://www.cleveland.com/outdoors/index.ssf/2013/03/changing_lake_erie_invasive_wh.html. Accessed 9/28/2017
USGS. “NAS -Nonindigenous Aquatic Species Morone americanus.” January 26, 2017. https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=777. Accessed 9/28/2017
Giant pandas, snow leopards, blue whales, and whooping cranes… What do all these species have in common? They are all endangered and well loved by many people. Most people are willing travel far and wide to see some of the world’s most endangered species, when they had one swimming right in their back yards here in Columbus, Ohio.
This endangered critter is called the Scioto madtom (Noturus trautmani). It is a small species of catfish in the family Ictaluridae. Unfortunately, the Scioto madtom has been listed as extinct on the IUCN Red List since they haven’t been found since 1957. Even if the Scioto madtom is labeled as extinct, they are still kept on the Endangered Species List so that if they are found again they get automatic protection. A total of 18 of these fish were found, the first being discovered in November of 1943 by Miltom Trautman. All of them were caught in a small section of the Big Darby Creek, which is a tributary of the Scioto River. The Big Darby creek is very high quality, making it a perfect habitat for pollution intolerant species, as most madtoms are. They were caught in a gravel bottomed riffle, which are shallow parts of a stream that causes ripples.
The Scioto madtom is small, only about 1.4 – 2.4 inches long. Their body is brown with four darker saddles across their back. They have a white or cream colored belly with sensory barbels hanging from their chin. Their caudal (or tail) fin is squared with a dark brown bar in the center (Ohio DNR Division of Wildlife). Like all madtoms, they have fin spines that contain a mild stinging venom.
Not much is known about this madtom, but researchers have been able to discover some traits. This fish would be a bottom feeder that uses its sensory barbels to find aquatic invertebrates (U.S. Fish and Wildlife Service). Not much is known about how the Scioto madtom reproduces, but scientistsbelieve that they spawn upstream in the summer and move downstream in the fall, as all of the 18 specimens were caught in the fall.
So go out and explore the natural world here in Ohio, because you never know, you might end up finding a new species or even catching one of these possibly extinct little catfish.
Sources:
Ohio DNR Division of Wildlife. “Ohio.gov / Search.” Ohio DNR Division of Wildlife, wildlife.ohiodnr.gov/species-and-habitats/species-guide-index/fish/scioto-madtom.
U.S. Fish and Wildlife Service. “Scioto Madtom (Noturus Trautmani).” Official Web Page of the U S Fish and Wildlife Service, www.fws.gov/midwest/endangered/fishes/sciot_fc.html.
Figure 1: Captures two children enjoying the outdoors with some quality fishing time.
For many Ohioans fishing is a hobby that they were brought up on and continue to share with their children, friends, and family. Although not all fishermen plan to consume their catch, many enjoy the satisfaction of putting a fresh meal on the table knowing they are the ones who caught it. Where I come from in north west Ohio fish fries are a common thing that bring a big crowd ready to gorge on as much fish as they can. The fish served at my local fish fries is often locally caught catfish. Catfish along with all other sport fish in Ohio are currently under a state wide consumption advisory.
A consumption advisory is set by the EPA based on sampling done in bodies of water throughout the state. There are thirty-six contaminants that are found in fish tissues that the EPA evaluates when determining if a location, species, or species within a location should have a consumption advisory. The EPA puts out specific advisories for each individual species and each specific location. Ohio is currently under a state wide consumption advisory for all sport fish. Currently in Ohio, the state advisory urges all adults to avoid eating more than eight ounces and children three ounces of state caught sport fish more than once a week. There are only two kinds of fish, yellow perch and sunfish that in most locations are deemed to be safe to each twice a week. However, several kinds of fish and fish within specific locations in Ohio have higher toxin levels and individuals are advised to eat them only once every month, once every couple months, or even not at all. The only way to know if the fish you are catching are safe to eat is to either test them yourself upon catch or simply look at the list the Ohio EPA posts.
Fig. 2: PCBs were mainly used for electrical equipment such as the one shown above.
So what contaminants do these fish have in them? The two most common contaminants in Ohio fish are polychlorinated biphenyls (PBCs) and methyl mercury. According to Environmental Defense Fund, “PCBs are man-made chlorinated industrial chemicals…” These chemicals are oily so they tend to not dissolve in water rather getting stuck on the bottom or staying in tact within the water. PBCs were banned in the US in 1979 however, since they take so long to break down we are still reeking the consequences today. With PCBs the oil is absorbed by the fatty tissue in fish. This is why leaner fish like Yellow Perch and Sunfish tend to be safer to eat. Methyl mercury however is a metal that fish absorb over time in their meaty tissue. Older fish and predator fish often have higher levels of mercury.
Figure 3: A basic model showing how methyl mercury enters water ways, and why predators tend to have higher levels of methyl mercury in their bodies.
So what can this do to people? People of all ages can be effected by these contaminants however, pregnant women and the fetus and young children are the most vulnerable. The contaminants in fish are often relatively low and don’t cause health risks if ate just once or twice it is the accumulation of being exposed. It is thought that PBCs can cause babies to be born under developed if their mothers consumed fish with high levels of PCBs. In young children PCBs are thought to stunt the developing nervous systems. In adult it is possible to effect memory and learning abilities. PCBs are speculated to be human carcinogens which means it is possible they they could cause cancer. Eating fish contaminated with mercury can cause you to develop mercury poisoning. According to Blue Voice “even low-level mercury poisoning has been found to cause memory loss, hair loss, fatigue, depression, difficulty concentrating, tremors and headaches. Because it is hard for the body to eliminate, it can build up and may affect the nervous system.”
So in conclusion, sport fish all throughout Ohio are contaminated at some degree. Most fish in Ohio however are safe to eat at some regularity. It is important to know the suggested serving sizes, which is eight ounces for adults and three for children, and the suggested regularity at which a fish is deemed safe to eat. If you are an angler who enjoys the satisfaction of catching your own meal, there are plenty of fish in Ohio that you can safely do that with. Just be aware that not every tasty looking fish that you may come across is safe to eat.
Figure 4: This example chart shows how the EPA lists species, locations, and contaminants on their website.
Work Cited
“Fish In Your Diet – Not Health Food Anymore: Mercury in Fish.” Edited by Troika Studio, Health Risks from Eating Mercury Contaminated Fish – BlueVoice.Org, www.bluevoice.org/news_toxicfish.php. Accessed 27 Sept. 2017.
“Ohio Sport Fish Consumption Advisory .” Ohio EPA Division of Surface Water, Apr. 2017, epa.ohio.gov/portals/35/fishadvisory/fishadvisory_pamphlet.pdf. Accessed 27 Sept. 2017.
“PCBs in fish and shellfish.” Seafood Selector, 19 Feb. 2013, seafood.edf.org/pcbs-fish-and-shellfish. Accessed 27 Sept. 2017.
Images:
“Are Children Spending Enough Time Outdoors?” Are Children Spending Enough Time Outdoors?, Eartheasy, 13 Apr. 2012, learn.eartheasy.com/2012/04/are-children-spending-enough-time-outdoors/. Accessed 27 Sept. 2017.
“Upper atmosphere facilitates changes that let mercury enter food chain.” Upper atmosphere facilitates changes that let mercury enter food chain, 19 Dec. 2011, Upper atmosphere facilitates changes that let mercury enter food chain. Accessed 27 Sept. 2017.
“Ohio Sport Fish Consumption Advisory .” Ohio EPA Division of Surface Water, Apr. 2017, epa.ohio.gov/portals/35/fishadvisory/fishadvisory_pamphlet.pdf. Accessed 27 Sept. 2017.
Introduced species have been a hot topic in the United States for quite some time regarding their abilities to disrupt native populations and cause environmental and economic harm. These plants and animals are introduced in a variety of ways and are generally the result of ignorance and lack of general knowledge on the subject. Fish, in particular, can be introduced in a variety of ways including; being released as a pet, exotic fish markets, or to control vegetation as is the case for carp. Carp were introduced in the United States in 1963 and are one of the most popular fish in the Midwest as they can be found in most of the Mississippi river basin and are used in lakes and ponds to control vegetation (Sutton, 1997). Efforts have been made to keep these animals out of waterways where they are not wanted like in the case of Lake Erie. Fish biologists and engineers have implemented electrical systems that keep the larger fish like carp from passing through but allow smaller fish to swim through freely. This system and systems like this have been used in many tributaries of Lake Erie trying to keep its waters free of unwanted pests like grass carp. With these systems in place, only a few individuals have ever been found in Lake Erie (Cudmore & Mandrak, 2004).
Sources:Grass carp, Ctenopharyngodon idella, are a larger carp species that can decimate areas from their aggressive eating habits (Leslie Jr et al., 1987). Researchers have recently found grass carp eggs in a Lake Erie tributary putting officials on guard. These carp are especially dangerous in this situation because of the damage they could do to the wetland restoration projects in the area (Miller, 2017). Wetlands are not only important for water quality but are home to many different animal and plant species. The introduction of the grass carp could destroy spawning grounds for some fish species and could have an impact on Lake Erie fisheries. They could also destroy possible nesting habitat for wetland bird species which include hunted birds like ducks and other species that are important to bird watchers which makes stopping the carp from getting to the lake extremely important. The team working on the case is using an electric current to stun the fish and net them. Their plans are to capture the fish before they get to the lake and spawn (Miller, 2017). This effort is why conservation is so important to the waterways in the United States. These efforts to keep grass carp out of Lake Erie are not only to benefit the wetland and its inhabitants but also for the good of the people. Lake Erie is a large diverse system with many connected waterways and wetlands. These are home to many fish, bird, and terrestrial animals that we hunt, watch, and photograph. These efforts to conserve the native fish species and vegetation in Lake Erie are imperative to the future care of our waters. This situation and situations like this are how we begin to become more proactive and protective of what we love dearly. I encourage all readers to be proactive in situations like this one and educate those who may not know about these issues to prevent future issues in our waterways.
Cudmore, B., & Mandrak, N. E. (2004). Biological synopsis of grass carp (Ctenopharyngodon idella). Canadian manuscript report of fisheries and Aquatic Sciences, 2705(7).
Sutton, D. L. (1977). Grass carp (Ctenopharyngodon idella Val.) in North America. Aquatic Botany, 3, 157-164.
Leslie Jr, A. J., Dyke, J. M. V., Hestand III, R. S., & Thompson, B. Z. (1987). Management of aquatic plants in multi-use lakes with grass carp (Ctenopharyngodon idella). Lake and reservoir management, 3(1), 266-276.
Porter, M. (2007). Controlling Aquatic Vegetation with Grass Carp. Retrieved September 26, 2017, from https://www.noble.org/news/publications/ag-news-and-views/1997/june/controlling-aquatic-vegetation-with-grass-carp/ (Picture)
Miller E. (2017). Grass carp eggs discovered in Lake Erie tributary. Retrieved September 26, 2017, from https://www.northcountrypublicradio.org/news/story/34656/20170914/grass-carp-eggs-discovered-in-lake-erie-tributary
People who consume caviar are usually considered “rich” or “having class.” How did this come to be? Did a royal chef somewhere run out of ideas and present this as an exotic new food and just get lucky? Actually, sturgeons, belonging to the family of Acipenseridae, were extremely abundant and easy to catch. Because they are also benthic, meaning bottom feeders, their meat and eggs was considered peasant food. In the early 1900s, caviar was actually served for free in American bars because of its salty taste to help sell more drinks.
The American species of sturgeons quickly became overfished at the same time that people were learning of the long amount of time necessary to harvest the caviar. This switched the eggs from being peasant food to part of “champagne wishes and caviar dreams.” The Caspian Sea was home to the Beluga sturgeon, the most sought after caviar. In the 1940s – 1950s, the Russians began initiatives to enhance the carrying capacity of the Caspian Sea for Belugas by introducing more biomass for them to feed on. This increased the population until the late 1980s, when the population dropped, and continued to drop. Russia banned commercial fishing of sturgeons over 10 years ago to help repopulate the species; but the black market for caviar rivals that of the drug dealers. Demand for Beluga caviar is strong across the globe and the price can range from $7,000 – $10,000 per kilogram.
Luckily for all of the caviar-lover’s out there, the Acipenseridae family also houses the Paddlefish. Once Americans realized that the Paddlefish caviar was just as good as the sturgeon caviar, the fishermen went wild. Once again, the Paddlefish were abundant in many of the waterways and were easy to catch. This made the Paddlefish caviar much cheaper, around $700 – $2500 per kilogram. By 1990, the American Paddlefish (Polyodon spathula) was on the verge of local extinction in many areas of the United States. Some states took action and began putting limitations on commercial fishing and began reintroduction programs to help the populations.
The Paddlefish is now listed as a Threatened species in Ohio, which means that all commercial and recreational fishing is prohibited. Even with this listing in Ohio and other states such as West Virginia, the population is still declining. How is this possible? For one thing, the Ohio river is not only in Ohio and Kentucky does not recognize the threatened status of the Paddlefish. So theoretically, you could catch all of the Paddlefish that you wanted to and claim the catch in Kentucky and it would be ‘legal.’ The second problem is that fish don’t have to stay in the state that they are protected, since the waterways are connected. The last major problem is that even though they may be protected from fishing, they are not protected from habitat fragmentation by dams and toxic waterways from pollutants.
Why care so much about the Paddlefish? Other species are suffering from overfishing and habitat fragmentation too, so why do the Paddlefish deserve our attention? There are two main answers to this. The first is that this species takes ten years to mature. That means that if a nine-year-old fish is accidently caught and killed, its life was wasted because it was not even able to reproduce. The second reason is that this species is a living dinosaur…they swam on this planet 75 million years ago! We cannot let this fish go extinct because we have to fulfill our caviar dreams.
So, what can we do? You can start by not eating caviar, but if you must, make sure that it is from a farm raised establishment that has been certified. Renee and Keith Koerner run Big Fish Farms outside of Cincinnati, where they raise and harvest their Paddlefish in the only sustainable fishery. By using farmed Paddlefish, this lets the wild populations regenerate, hopefully. There is some worry that the Paddlefish are going “the way of the buffalo” since they have been extirpated from much of the western United States. Reintroduction is an option, but it can be costly and time consuming, given they will not be able to sustain their own levels until at least ten years afterward. In South Dakota, they recently released 79,000 paddlefish into two of their lakes. For this fishing community in Southeast South Dakota, they are committed to bringing back their Paddlefish population for the health of their waterways and for recreation. However, the black market for caviar does not seem to be going anywhere, as Missouri has been named the “caviar smuggling capital.” To battle the illegal catch of paddlefish on a civilian level is simply to just “see something, say something.” This action is more helpful than most people think and can be helpful in saving the species.
So to recap, if you…
don’t eat caviar/only eat farmed caviar
release any accidental paddlefish caught
see illegal fishing and say something
Then you help bring back a living dinosaur from the edge of extinction! If you want to do more with reintroduction efforts and volunteer work with Paddlefish, contact your local Department of Natural Resources office and ask for more information. Needs and strategies vary among states and regions.
Billard, Roland and Guillaume Lecointre. (2001). Biology and conservation of sturgeon and paddlefish. Reviews in Fish Biology and Fisheries 10:355-392
Campbell, Polly. (2017, March 21). Cincy caviar ranchers bringing indulgence to your plate. The Enquirer, Retrieved from http://www.cincinnati.com/story/entertainment/dining/2017/03/21/cincy-caviar-ranchers-bringing-indulgence-your-plate/98260684/
Cooper, Katherine. (2016, March 30). Why the Caviar-Producing American Paddlefish Is a Symbol of Luxury and Scarcity. Kansas City Star, Retrieved from https://www.eater.com/2016/3/30/11250870/american-paddlefish-caviar
Preston, Geoff. (2017, Sep 14). Over 79,000 paddlefish released in Lake Francis Case and Lake Sharpe. Rapid City Journal, Retrieved from http://rapidcityjournal.com/sports/over-paddlefish-released-in-lake-francis-case-and-lake-sharpe/article_9ae66c0e-25ad-50b3-92de-a3c607ee6d30.html
Secor, D. H. et al. (2000). Restoration of sturgeons: lessons from the Caspian Sea Sturgeon Ranching Programme. Fish and Fisheries 1:215-230
Zabyelina, Yuliya G. (2014). The “fishy” business: a qualitative analysis of the illicit market in black caviar. Trends in Organized Crime 17:181-198
In Ohio, we have bodies of water everywhere! Whether it’s coming down from the sky in buckets, or is in our streams, rivers, or Lake Erie up north, people who live here see it all the time. Have you ever wanted to know how clean the water that you come across is? The best “people” to ask are the fish that live in it! Some species of fishes are picky about the water they live in, so you only find them in water that is pretty clean. Other species can survive in water that is quite dirty! Scientists often study the types of fish they find in a body of water to help them see how clean or polluted that water is. These types of fishes are called “indicator species” because they indicate the cleanliness of the water.
The three fish pictured below are from the family Ictaluridae, which is often called the catfish family. Since catfish are so well known across Ohio, I’ve chosen three species from this family that can tell you a little bit about the quality of the water they live in. So if you find these guys in the wild, you’ll have an idea of how clean the water might be!
Species #1: Brown Bullhead Ameiurus nebulosus
This guy is definitely not a finicky fish! Brown Bullheads are good at surviving in all kinds of environments, clean or polluted. This is why scientists have classified them as a “tolerant species.” If you are only catching fish of this species, there’s a good chance that the water isn’t super clean.
Species #2: Channel Catfish Ictalurus punctatus
The Channel Catfish is a bit pickier than the Brown Bullhead, so scientists have classified this species as “intermediately tolerant.” It doesn’t need extremely clean water to survive, but it doesn’t like super polluted water either. If you catch a bunch of these catfish, the water is probably so-so in terms of cleanliness.
Species #3: Brindled Madtom Noturus miurus
This is definitely a finicky fish! Brindled Madtoms don’t survive well in polluted water at all. Scientists have classified this species as “intolerant” of pollution for this reason, and this make them a great indicator of water quality. If you find a Brindled Madtom out in the wild, there’s a good chance that the water you’re in is pretty clean!
Sources:
DNR Cornell. (n.d.). Brindled Madtom [Illustration]. Retrieved from http://www2.dnr.cornell.edu/cek7/nyfish/Ictaluridae/brindled_madtom.html
Washington Department of Fish and Wildlife. (n.d.). Brown bullhead [Illustration]. Retrieved from http://wdfw.wa.gov/fishing/washington/Species/1165/
Reece, M. (n.d.). Channel Catfish [Illustration]. Retrieved from http://www.iowadnr.gov/Fishing/Iowa-Fish-Species/Fish-Details/SpeciesCode/CCF
United States Environmental Protection Agency, National Service Center for Environmental Publications. (2008). An Introduction to Freshwater Fishes as Biological Indicators. Retrieved from https://nepis.epa.gov/Exe/ZyPDF.cgi/P1002J1W.PDF?Dockey=P1002J1W.PDF
This site is dedicated to telling fish tales to encourage respect for and awareness of the fishes of Ohio and beyond. All #scicomm posts are created by students of ENR 5350.02 Taxonomy and Behavior of Fishes.
Students sampling the Olentangy River at the Wilma H. Schiermeier Olentangy River Wetland Research Park, The Ohio State University.
