Helping kids understand what does McKinsey do?

McKinsey for Kids: Hungry fish, baffled farmers, and what happened next

October 29, 2020Interactive

You’re a kid. You’ve heard of McKinsey—maybe your parent even works here—yet you don’t quite get what we do all day. You’re not alone—many adults don’t either. Basically, we help solve problems. And many of those problems affect you directly: how to improve education, or tackle climate change, or design products that you and your friends might like. Let’s look at, say, fish: Have you eaten sushi lately, or fish sticks, or a fish sandwich? Here is how we helped some farmers in Latin America who might have grown that fish. Check it out.

Down on the fish farm

When you see the word “farming,” what do you think about? Maybe a farmer, a tractor, or a cow grazing in a field ... but probably not a fish.

But, yes, there are farms that raise the fish that we often eat—fish sticks, fish burgers, fish fillets—at home or in restaurants. There are farms for other types of seafood as well, such as shrimp and oysters.

What types of seafood are farmed?

Carp

Carp is the most farmed fish in the world, with 28 million tons harvested each year. Carp is mainly farmed in China and India, where people eat a lot of it. Those countries also send their carp to other countries across the world (this is called “exporting”).

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Fish farms are also called aquafarms. Fish farmers build enclosed spaces in oceans, lakes, and even in indoor greenhouses where the fish swim and live—and eat. These aquafarms need a lot of food for the fish and constant care to make sure the fish that live in them are healthy.

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Let’s dive in

Wondering how a fish farm works? Let’s take a deep dive into some of the machines, people, and equipment that help the fish we eat live, grow, and stay clean and healthy.

A barge is a large boat that holds feed tanks, a control room with sensors and cameras, living quarters for the farmers, and plenty of safety equipment. The barge is like a floating home and office in one.

Divers work on fish farms too. They can spend up to five hours per day underwater, where they monitor what’s going on with the enclosures where the fish are kept, and collect fish during harvest. Fish-farm divers have difficult jobs—they wear heavy equipment and work underwater for hours, rain or shine.

Fish enclosures come in many sizes, and the number of fish they can hold depends on what type of fish is inside. Some can be three times the size of an Olympic swimming pool. Enclosures have nets that keep the fish in the area where the farmers want them. Heavy weights are attached under the nets to keep the enclosures anchored to the sea floor and make sure strong waves don’t move them too much.

Much like our home fish tanks, a cleaning system is critical. It maintains proper oxygen levels, limits algae buildup, and reduces fish waste in the enclosures. Cleaning systems rotate water in and out of the enclosures, filtering impurities out of the old water before it’s released into the fishes’ living area again.

Feeding tubes release fish oils, minerals, vitamins, and plant proteins like soy and corn into the area where the fish live, so they can eat. Feed tanks are stored on the barge, and some tanks can even float on the surface of the water by themselves.

How much is 25 million tons of fish?

That’s almost one trillion fish sticks! And it’s how much experts say the amount of fish grown on aquafarms and caught in the sea will probably increase each year, by 2030.

When farmers are raising hundreds of thousands of fish that grow quickly, how do they know how much fish food to buy? The fish are underwater, so it’s not easy for farmers to know their exact ages or what they’re doing. All these things affect how much food the fish need. (Farmers who raise cows on land can find all this out much more easily just by looking at the cows or, simply, weighing them.)

Many fish farmers try to guess how much food to buy, but they often buy more than they need because they’re afraid of running out and leaving their fish hungry. But if they buy too much, a lot of food and money can also go to waste.

So what does this have to do with us? A company that sells fish food decided to try to help farmers understand how much food to buy. Everyone knew that the old system of buying food was not working, but they didn’t know how to solve the problem—so they asked us at McKinsey to come in and help.

The food company chose McKinsey.
But why us?

A lot of smart, curious people join McKinsey because they like helping people solve big problems. Some of us are engineers. Others are designers. Others are scientists, or doctors, or researchers, or even writers and editors. Companies usually ask us for help when they are dealing with a tough problem and aren’t sure what to do about it. We put together teams of McKinsey people who can help. We always look for a mix of skills—just like on a sports team, where athletes with different strengths play different positions. And we have a deep bench.

Some of the roles at McKinsey

Economist

An economist at McKinsey tells a company how it might improve its business and profits over the next five, ten, or even 20 years. You might like this job if you’re interested in how money is made and spent. In this example, an economist realized that farmers struggled to know how much food they should buy.

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To help this fish food company, we picked a team that included experts in agriculture (farming), business operations (such as how the fish makes its way from the farm to the supermarket), and sustainability (the environment), among many others.

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What do fish eat?

Like humans go from milk to baby food to solid food, fish have different feeding needs at different stages of their lives. Here’s an example of how a salmon’s diet changes as it grows up.

A salmon egg is the size of a pea, and it takes about three months to grow and develop. In the wild, eggs rest under loose gravel in freshwater rivers that connect to the Atlantic and Pacific Oceans. On an aquafarm, salmon eggs rest in a tray that resembles their natural freshwater environment.

When a baby salmon hatches out of the egg, it is called an alevin for the first five weeks of its life. A yolk sac, filled with nutrients, is attached to the alevin’s body. The alevin feeds off the yolk sac until the sac is gone, so it doesn’t need to be fed fish food by farmers. Once the alevin uses up the yolk sac, the young fish swims to the surface to look for food.

For the fifth through tenth weeks of a salmon’s life, it’s called a fry. On an aquafarm, a fry is moved from a small tray to a larger tub called a freshwater hatchery.

A young salmon between three and 12 months old is called a parr. During this stage, the parr develops vertical stripes and spots for camouflage. In the wild, these patterns protect the growing salmon from predators.

Once the young salmon is about a year old, it is called a smolt and can survive in saltwater. On an aquafarm, the smolt is loaded onto a transport boat and moved from the freshwater hatchery to a large saltwater sea enclosure. A smolt is silver-colored, about five inches long, and only weighs about 80 to 120 grams.

A salmon is fully matured and considered an adult when it’s about three years old, but it continues to grow during adulthood. On an aquafarm, adult salmon are located in large enclosures that have lots of saltwater rotation to help keep the habitat clean. An adult salmon can grow to 28 to 30 inches long and weigh 8 to 12 pounds.

So what did people on this fish team do? First, they listened carefully to the folks at the client (the fish food company), to understand the problem they were trying to solve. The team also talked to fish farmers to understand the problem from their side, and got information from other McKinsey experts who know a lot about farming as a business. One of the first things the team learned was that fish farmers were spending more than half of their money buying fish food. And some of that food was never used because the farmers bought too much.

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Meanwhile, our client wanted to do more than sell food to the farmers; it really wanted to help the farmers know how much food to buy. Then the farmers would feel confident that they were buying the right amount. And because the company helped the farmers reduce waste, they would, hopefully, buy from that company again, rather than buy from someone else.

Knowing what the client was trying to do, the McKinsey team gathered more experts—who knew a lot about digital technology and analytics (solving problems with numbers)—to work with them. These experts built a computer “model” to accurately track the ages, weight, and movement patterns of different kinds of fish. We think of the model almost like a video game. By playing with it, the farmers could see how much food fish ate in past years and on other fish farms around the world. Then they could use that information to predict how hungry their fish would be. This could help the farmers save money and waste less food.

Delivering success

When we build computer models for clients, we want to make sure they are useful now—and that they stay useful well into the future. Folks at the client should be able to enter new information all the time and still solve the latest problem—even if the team that built the model has finished the “engagement,” which is what we call the time we spend helping them. So we work with the client to test the model and make sure it really helps. Often, we tweak the model based on such tests.

And that’s exactly what we did with the fish farm engagement. The project manager coached the client on how to continue to help the fish farmers for a long time, even after McKinsey handed off the final computer model.

Fast forward to today. The fish farmers are buying the right amount of food they need from the company that helped them, and they aren’t wasting their money or fish food. Even better, the model continues to learn how to adjust the amount farmers feed to their fish based on factors such as weather, sea currents, oxygen levels, and location. These affect the weight and size of fish, and they naturally change constantly. So the model keeps getting smarter, helping the farmers get better at their work. The farmers are expected to increase their productivity by up to 8 percent, which might not seem all that big to you after all this work, but it makes a huge difference to their incomes.

With the farmers happy and the client feeling like it solved a major problem, normally it’s time for the engagement to come to an end. McKinsey is paid for its work, and our colleagues typically move on to other projects around the world. But often things have gone so well that a client will want McKinsey to help them with other problems. And that is what is happening at this fish food company. This past summer, a McKinsey team has also started working with the client to develop new devices that use what’s called “Internet of Things” technology (analytics help the devices tell users what to do—or have the devices go ahead and do them automatically) to feed fish at the right times and in the right amounts. They also started testing computer-vision cameras that can help track fishes’ body mass, weight, and movement. And having spent all this time with the client, our team has also found other areas where they could improve their broader business portfolio. To be continued …

This interactive experience is based on a post on the New at McKinsey blog edited by Molly Katz, and a related article McKinsey published here on improving ocean fishing with technology. It was a collaborative effort from McKinsey Global Publishing, where Richard Johnson came up with the visual idea and created the illustrations, and Mike Borruso, Vanessa Burke, Nancy Cohn, Caroline Dudlak, Torea Frey, Marcelo Garza, Justine Jablonska, Eleni Kostopolous, Stephen Landau, LaShon Malone, Janet Michaud, Lucia Rahilly, Charmaine Rice, Dan Spector, and Nathan Wilson all helped bring it to you.

If you have read this far, we hope you have enjoyed it. Want to tell us what you thought and how we could have made it even more enjoyable and useful to you? And should we do more such stories? Drop a note to our Publisher, Raju Narisetti, at newideas@mckinsey.com.