Author: Alec Dumbauld

 

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

     As an angler, I would contest that carp are not the prettiest fish or the most prestigious but they are a heck of a lot of fun to catch.  As a young boy, my brother (shown on the left) and I always loved to go to the nearby lakes and ponds and catch whatever we could. We would hear tales about released pet fish that grew to gigantic sizes that ruled the lakes and ponds.  We would always go for our friend’s goldfish that they released into the city lake to no avail.  Catching fish and understanding their importance grew on my brother and I from a young age and fueled us to catch as many different fish as we could.  This thrill for the catch is what fuels conservation efforts and education from the very kids who grew up having this childhood.

Recently in Pymatuning Lake in northeastern Ohio, thousands of carp have washed up on the shore for what looks like no reason.  Upon investigation, it was determined that these fish all died because of Koi herpes virus (KHV), a virus that causes mass mortality in carp (Kempter et al., 2012).

As I have become older I have realized how bad it is to release pet fish into the wild.  These fish can transmit diseases to the wild populations and can have terrible effects on the local population numbers.  Once a pet fish is released it can infect carrier fish in the wild so that even if the pet fish gets eaten or dies, that KHV is still alive in the environment.  Common carriers in Pymatuning lake are other species of carp along with northern pike and possibly pet fishes released into the lake.  Officials on scene at Pymatuning are saying that the virus has a mortality rate of between 80-90% which is very high for a contagious lake virus (Knoedler, 2017).  This is increasingly important because carp make up a good portion of most bodies of water when they are present with percentages ranging up to 96% of all fish biomass in some areas (McColl et al., 2007).  The good news in this situation is that the virus is very specific to carp so there is little concern that it will spread to other fish types.  It is believed that this year’s cold weather should kill the virus over time (Knoedler, 2017).

Conservation and public education are important for the public in situations just like this which is why when things like this happen experts are very reactionary and will throw a great deal of information into the public light to educate the public as much as possible.

This situation just goes to show that the tales about fish being released into lakes should stay tales and should not become a reality.  From this situation, the severity of releasing fish becomes more apparent to those who may lack knowledge of how bad the activity really is.  So just keep in mind that next time a pet goldfish is released into a pond or lake it could spell the end for the native species that call the body of water home.

Sources:

Kempter, J., Kielpinski, M., Panicz, R., Sadowski, J., Mysłowski, B., & Bergmann, S. M. (2012). Horizontal transmission of koi herpes virus (KHV) from potential vector species to common carp. Bull Eur Assoc Fish Pathol, 32, 212-219.

Knoedler, M. (2017, September 21). Dead carp test positive for virus in Pymatuning Lake. Retrieved September 25, 2017, from http://www.erienewsnow.com/story/36426536/dead-carp-test-positive-for-virus-in-pymatuning

McColl, K. A., Sunarto, A. G. U. S., Williams, L. M., & Crane, M. S. T. J. (2007). Koi herpes virus: dreaded pathogen or white knight. Aquaculture Health International, 9, 4-6.

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.

1. Cudmore, B., & Mandrak, N. E. (2004). Biological synopsis of grass carp (Ctenopharyngodon idella). Canadian manuscript report of fisheries and Aquatic Sciences, 2705(7).
2. Sutton, D. L. (1977). Grass carp (Ctenopharyngodon idella Val.) in North America. Aquatic Botany, 3, 157-164.
3. 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.
4. 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)
5. 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