Fish are friends AND food

Many people don’t think about fish beyond what’s in their tanks or on their plate. Fish are actually a valuable and important focus for research efforts. I have trillions of reasons why!

I have always loved fish. The diversity in visual splendor and quirky behaviors drew me to them when watching ocean documentaries as a child. However, the explanation “because they’re awesome!” doesn’t cut it when you want to conduct research. Research costs money, and whether that money comes from private industry or the government, it’s essential that researchers can justify the use of their study organisms. Today, I’m going to break down the equation of why fish are worthy and need research funding.

There are at least 33k living species of fish, accounting for over half of living vertebrate species [1]. This incredible diversity includes jawless lamprey, cartilaginous sharks, rare deep-sea coelacanths, colorful clownfish, and so much more (Fig. 1)! Fish around the world have adapted to all types of habitats, from the freezing waters of the Arctic to the deepest trenches of the ocean. There is much to learn from fish about how vertebrates were able to survive in changing and even inhospitable environments.

Figure 1. Can you name all these different fish?

(Answers: top left – lamprey by Northwest Power and Conservation Council, top right - stingray by Flyon Like a Lion, bottom left – coelacanth by Greg Morrow , bottom right – parrotfish by David)

Fish have inhabited the earth for over 500 million years (ancient and awesome). In this time, fish have become an integral part of the marine and aquatic food web (Fig. 2). Some fish feed directly on low-trophic level organisms like plankton, algae, and marine plants. These fish usually serve as food for larger fish and marine mammals. As a result, significant changes in fish abundances can cause a trophic cascade, affecting levels of prey (like algae, plankton, jellyfish) and/or predators (like tuna, swordfish, sharks). Maintaining healthy levels of fish is integral to maintaining a healthy ecosystem.

Figure 2. An example of an aquatic food web in Lake Superior (Source: NOAA Great Lakes). Make your own trophic cascade: pick a fish and trace all of the species that would be directly and indirectly affected if that species was removed from the ecosystem.

Worldwide coastal tourism was valued to be $161 billion in 2008 [2]. Fish are beautiful to see in their natural habitat and also are a popular target for people who like to eat delicious and nutritious food. Tourism concerning marine and aquatic ecosystems includes recreational fishing, snorkeling/scuba diving, and boating (Fig 3). It is difficult to know what percentage of this is attributable to fish. Even so, consider that even if fish are not what people came to see while on vacation, fish are likely to affect local animals (prey for birds, sea lions), habitat (cleaner of corals), and even quality of beach sand under your feet (see parrotfish poop).

Figure 3. Snorkeling is one of my favorite ways of feeling close to the ocean. There’s nothing like looking a fish in the eye to take your breath away! (CC0 Public Domain)

In 2012, fish products contributed $137.7 billion in aquaculture and $129.2 billion in exports worldwide [3]. Many people in developed countries greatly enjoy the taste and nutrition that fish provide. In developing countries, catching fish is a way of putting food on the table or providing for your family. Fish are an incredibly important source of protein for the world. The global population is predicted to increase to 9.6 billion people by 2050, meaning that we must continue developing methods and technologies to produce enough food to feed all those mouths. Fish are a natural food source, but they are by no means unlimited. Implementing sustainable fishing practices and maintaining healthy ecosystems worldwide will be essential to foster productive populations of fish. You can read more about sustainable seafood here and learn how anyone can contribute toward building this food source for the future.

Last but not least, evolution’s gift to me: there is a cowfish, and it has horns (Fig 4).

Figure 4. Couldn’t help myself. Look at that cutie! (CC0 Public Domain)

Let’s add up the value of fish research:

33,200 + 500,000,000 + 161,000,000,000 + 266,900,000,000 + 1 = 267,561,033,201

(Please send in the form of a fish-shaped check to the poor graduate student fund (my bank account)!)

Fish are a vital part of ecosystems and economies around the world. Therefore, it is important to support scientific research to understand and maintain an environment that sustains healthy fish populations. Go fish!

References:

[1] Hastings, Philip A., Walker H. J., and Galland Grantly R. Fishes: A Guide to Their Diversity. University of California Press, 2014. http://www.jstor.org/stable/10.1525/j.ctt9qh2k9.

[2] An Overview of the State of the World’s Fresh and Marine Waters 2008. http://www.unep.org/dewa/vitalwater/article168.html

[3] FAO. 2014. The State of World Fisheries and Aquaculture 2014. Rome. 223 pp. http://www.fao.org/3/a-i3720e.pdf

Fish are friends AND food

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