While deep space might seem like the ultimate mystery, we actually know more about the stars orbiting the supermassive black hole at the center of our galaxy than we do about the mysterious creatures living in the deep oceans on Earth. More than 60% of our planet is covered by water deeper than a kilometer, making it the most common environment on Earth, yet one we know very little about.
The creatures that live in these dark, cold, and high-pressure depths have developed incredible adaptations to survive. At a depth of one thousand meters, the pressure is more than 100 times what we experience at sea level. This pressure is so intense that it could compress the air in a soccer ball down to the size of a ping pong ball and a half!
Unlike most fish, deep-sea fish don’t have gas-filled cavities like swim bladders, which would collapse under such pressure. Instead, they have minimal skeletons and jelly-like flesh, relying on water as their structural support to withstand the extreme conditions.
For a long time, deep-sea fish were left undisturbed. However, as fish populations near the coast began to dwindle, fishermen ventured further out to sea, discovering large and tasty fish in deeper waters. As they depleted the fish near the surface, they started fishing deeper, which changed the game entirely.
Deep-sea fish are perfectly adapted to their environment but are not equipped to handle modern fishing practices. The cold temperatures and scarce food supply mean fewer fish live in the deep, and those that do grow slowly, affecting their reproduction rates. For instance, the orange roughy, a fish that can live over a century at depths of 500 to 1500 meters, can only replace 6% of its population each year. In contrast, fish like cod, mackerel, and herring can replace half of their population in the same time frame.
When commercial fishing for orange roughy began in the 1980s, the catches were initially abundant. However, within 25 years, the fish became scarce. This situation is similar to mining the oceans, which is unsustainable for both the fish and the fishermen who rely on them for their livelihoods.
If we could learn to fish at a rate that allows fish populations to replenish naturally, it would be beneficial for the fish, the fishermen, and our future food supply. While we might one day mine asteroids for minerals and precious metals, as far as we know, there are no fish in space. Therefore, it’s crucial to protect the ones we have here on Earth!
Using materials like clay, paper, and paint, design a model of a deep-sea creature. Think about the adaptations these creatures have for surviving in high-pressure, dark environments. Present your model to the class and explain how your creature’s features help it survive in the deep ocean.
Conduct an experiment to understand the effects of pressure. Use a plastic bottle filled with water and a balloon to simulate how pressure changes with depth. Discuss how deep-sea creatures adapt to such pressures and compare it to your experiment results.
Research the impact of deep-sea fishing on marine life and prepare for a class debate. One group will argue for stricter regulations on deep-sea fishing, while the other will argue for the economic benefits of fishing. Use evidence from your research to support your arguments.
Watch a documentary about deep-sea exploration and the creatures that inhabit these depths. After viewing, discuss in groups the new information you learned and how it relates to the need for sustainable fishing practices.
Design a campaign to raise awareness about the importance of sustainable fishing. Create posters, social media posts, or a short video to educate others about the impact of overfishing on deep-sea ecosystems and the importance of conservation efforts.
Deep space may be the final frontier, but we already know more about the orbits of stars around the supermassive black hole at the center of the Milky Way than we do about the behavior of the colossal squid and other creatures that live deep in the oceans here on Earth. In fact, water deeper than a kilometer covers more than 60% of the planet, which means we know very little about the most common environment on Earth.
Creatures that inhabit these depths have adapted to survive in constant darkness, near-freezing temperatures, and extreme pressure, all of which result in limited oxygen, food, and companionship. Surviving in this environment requires extraordinary adaptations. At a depth of one thousand meters, the pressure is over 100 times what we experience at the surface, enough to compress the air in a soccer ball to the size of a ping pong ball and a half.
Unlike most fish, those that live in these depths do not have gas-filled cavities like swim bladders, which would collapse under the extreme pressure. Instead, deep-water fish often have minimal skeletons and jelly-like flesh, as the only way to withstand the extreme pressure is to have water as their structural support.
Until recently, deep-water fish were largely left alone, but as coastal fisheries became depleted, fishermen began venturing further out to sea, where they discovered large, tasty fish. As they caught and depleted the fish near the surface, they simply fished deeper. However, fishing at these depths is a game changer. These fish are remarkably well adapted to the pressures of the deep ocean but are ill-equipped to handle modern fishing practices.
Cold temperatures and a lack of food mean that fewer fish inhabit the deep, and those that do grow slowly, which also affects their reproduction rates. For example, the orange roughy (Hoplostethus atlanticus) can live for over a century at depths of 500 to 1500 meters below the ocean’s surface. At their best, they can only replace 6% of their population each year, while shallow-water fish like cod, mackerel, and herring can replace half of their population in the same time frame.
When commercial fishing for orange roughy began in the 1980s, the catch was remarkably good, but within 25 years, most nets came up empty. Essentially, we are mining the oceans, which poses challenges for both orange roughy and other slow-growing but sought-after species, as well as for the fishermen whose livelihoods depend on them.
If we could learn to harvest fish at the same rate they can replenish their populations, it would benefit the fish, the fishermen, and our future cuisine. While we can always mine asteroids for minerals and precious metals, as far as we know, there aren’t any fish in space, so we should be protective of the ones we have here on Earth!
Deep – Extending far down from the top or surface, often referring to the ocean or sea. – The deep ocean is home to many unique species that have adapted to the high pressure and low light conditions.
Ocean – A vast body of saltwater that covers almost three-quarters of the Earth’s surface. – The ocean plays a crucial role in regulating the Earth’s climate and supporting marine life.
Fish – A cold-blooded, gill-bearing aquatic vertebrate that typically has fins and scales. – Many fish have developed special adaptations to survive in different environments, such as camouflage or bioluminescence.
Pressure – The force exerted by the weight of water above, increasing with depth in the ocean. – Deep-sea creatures have evolved to withstand the immense pressure found at the bottom of the ocean.
Environment – The surrounding conditions in which an organism lives, including air, water, and land. – Changes in the environment, such as pollution, can have significant impacts on marine ecosystems.
Adaptations – Changes in an organism’s structure or behavior that help it survive in its environment. – The polar bear’s thick fur and fat layer are adaptations for surviving in cold climates.
Fishing – The activity of catching fish, either for food or as a sport. – Overfishing can lead to a decline in fish populations and disrupt marine ecosystems.
Sustainable – Using resources in a way that meets current needs without compromising the ability of future generations to meet theirs. – Sustainable fishing practices help ensure that fish populations remain healthy and abundant.
Population – A group of individuals of the same species living in a particular area. – Scientists study the population of dolphins in the bay to understand their breeding patterns and health.
Supply – The amount of a resource or product that is available for use. – The supply of clean water is essential for the survival of all living organisms.
