Understanding Sharks and Their Role in Ocean Conservation

sarah88492
Jul 29
4 min read

Updated: Sep 2

Sharks are one of the most ecologically significant animals in our oceans, yet they’re one of the most misunderstood. Many species are now facing serious population declines, and their disappearance carries consequences for marine ecosystems, global ocean health, and climate stability.

Sharks and Ecosystem Balance

Sharks are apex and mesopredators, meaning they often sit at the top or near the top of the food chain. Their presence shapes the behavior and population size of species below them. This regulatory effect, known as top-down control, is critical for maintaining ecosystem balance.

For example, in coral reef systems, sharks help control populations of mid-level predators such as groupers or snappers. When shark numbers decline, these species can overpopulate and reduce the number of herbivorous fish, which are essential for grazing algae that would otherwise overwhelm the reef. Without sharks, the entire reef system can shift out of balance, leading to coral degradation and loss of biodiversity.

In open ocean systems, pelagic sharks regulate prey like tuna and squid, preventing overgrazing on smaller fish and invertebrates. Some sharks, such as tiger sharks, even influence the movement and behavior of species like sea turtles and dugongs, which in turn affects the health of seagrass beds—important carbon sinks that store large amounts of atmospheric CO₂.

Nutrient Cycling and Habitat Health

Beyond predation, sharks contribute to nutrient cycling in the ocean. Species like whale sharks and basking sharks feed on plankton and microscopic organisms, helping to regulate their abundance. Scavenging sharks consume dead or dying animals, preventing the spread of disease and recycling nutrients back into the ecosystem.

When sharks move through different zones of the ocean—deep sea, reefs, open water, coastal areas—they help redistribute nutrients vertically and horizontally. This movement supports productivity in low-nutrient environments and enhances habitat resilience.

The Global Decline of Shark Populations

Despite their importance, shark populations are in steep decline. A 2021 study published in Nature found that the global abundance of oceanic sharks and rays has declined by over 70% since 1970, primarily due to overfishing.

Key drivers of this decline include:

Bycatch: Sharks are frequently caught unintentionally in nets and longlines targeting tuna or other commercial species. Many are discarded dead or dying.
Shark finning: This practice involves removing the fins (used in shark fin soup) and discarding the body at sea. It's illegal in many countries but still widely practiced due to lack of enforcement.
Slow reproduction rates: Most sharks are K-selected species, meaning they mature slowly, produce few offspring, and have long gestation periods. This makes population recovery especially difficult.
Habitat degradation: Coastal development, pollution, and climate change are impacting nursery grounds and migratory routes, making it harder for sharks to breed and survive.
Poor management and data gaps: Many countries lack accurate data or adequate conservation policies for sharks, making it difficult to protect vulnerable populations.

Ocean Conservation Starts With Apex Predators

Healthy oceans depend on intact food webs. Removing apex predators like sharks has ripple effects. Their absence can trigger trophic cascades, where the loss of one species causes major shifts in ecosystem structure and function. These changes can reduce fishery productivity, increase disease transmission, and accelerate habitat collapse.

Furthermore, ocean health is tied directly to climate regulation. Oceans absorb about 25% of the world’s carbon dioxide emissions and over 90% of excess heat from global warming. Ecosystems like seagrass beds, kelp forests, and coral reefs help store carbon and protect coastlines—but they’re all connected to species that sharks help regulate.

In other words, conserving sharks means preserving the entire marine system they help sustain.

What Science Tells Us (and What Still Needs to Be Done)

Modern research uses satellite tagging, genetic analysis, and AI-powered data modeling to better understand shark migration, behavior, and population trends. Scientists have identified critical habitats, migratory corridors, and reproductive patterns for dozens of species.

Still, over one-third of all shark and ray species are now threatened with extinction, according to the IUCN Red List. Many of these species remain poorly studied, and new ones are discovered every year. The more we learn, the clearer it becomes: conservation efforts must be science-based, globally coordinated, and culturally informed.

What Students and Educators Can Do

Ocean conservation is a complex, interdisciplinary challenge—but education plays a central role in solving it. Here are a few ways students and teachers can take part:

Study marine science: Learn about ecology, climate systems, and environmental policy. Platforms like Thea can help make these subjects accessible and engaging.
Stay critical of media: When sharks are portrayed as violent or expendable, ask why. Seek out research-based documentaries and articles.
Support sustainable seafood choices: Overfishing impacts more than just sharks. Choosing sustainably sourced fish helps reduce bycatch and protect marine food chains.
Raise awareness: Talk about sharks in the classroom. Share what you learn with peers and on social platforms. Awareness leads to action.
Engage in citizen science: Organizations like Shark Trust and eShark collect data from divers, boaters, and students to support conservation.

Final Thoughts

Sharks are older than the dinosaurs. They’ve survived mass extinctions and global climate shifts—but they might not survive us. Protecting sharks means securing the future of our oceans, our climate, and our planet.

Shark Week is the perfect time to look past myths and focus on science. At Thea, we believe that curiosity leads to understanding—and understanding leads to change.