There are around 90 species of whales alive today, and they cover a wide range of sizes and shapes; from the smallest, measuring 3 meters and 135 kilograms, to the largest, 29,9 meters and 190 tons, whales live their lives in the ocean, and they are vital to survival on Earth.
Protecting the whales is essential to prevent the disappearance of these charismatic sea creatures with their peculiar evolutionary path. It is also crucial in the desperate fight against climate change. In fact, these cetaceans provide an invaluable ecosystem service: they are able to sequester large quantities of carbon from the atmosphere, helping to fight global warming.
In addition, whales have a key involvement in the ecosystem, and they play a critical role in maintaining the health of the ocean. Over the years, the decline of the whale population has altered the structure and function of the oceans, demonstrating the strong influence of these animals on marine ecosystems.
What are some threats faced by Whales?
Since the 17th century, industrial hunting of marine mammals has been practiced and it was only when the whale population declined significantly, around the 1980s, that environmentalists acted in the interest of defending whales.
Currently, only three countries in the world still practice whaling: Japan, Norway, and Island. However, just recently, this last declared that it will stop whaling in 2024.
Whaling is mainly practiced for meat, which is still a typical product in these countries, as well as in many populations living in the United States and Denmark; in these areas, communities hunt and consume some animals every year, as in the famous, controversial massacre of Faroe Island.
Today, there are other factors that impact the welfare of whales, some directly related to human presence, such as noise pollution and intensive fishing, and others related to the present environmental situation, such as pollution and climate change.
The role of whales in the ecosystem
Whales feed on plankton, krill, small fishes, and crustaceans. Krill are very important in the food chain, as fish, whales, seals, penguins, and many other species eat these small crustaceans.
Undoubtedly, the phenomenon known as the ‘Krill paradox’ describes well the importance of whales in the ecosystem. It could have been assumed that a decrease in the population of these cetaceans would lead to an increase in the number of krill and fish, but the exact opposite happened; in fact, whales increase the number of krill and fish in the ocean through fecal fertilization. Indeed, their feces contain iron and nitrogen, substances necessary for the growth of these organisms.
Areas that lost great whales had a decline of many species, such as sea otters and birds of prey. Studies have shown that also phytoplankton populations are correlated to whales’ presence. Furthermore, the carcasses of whales provide a deep-sea habitat for more than 100 species. All this shows how important whales are for the ecosystem and the survival of other species.
In addition, whales are important for nutrient cycling, as the physical movement of these large animals helps the distribution of nutrients and oxygen in the water. In fact, through the “Whale pump”, described as vertical movements from the bottom to the surface, and the “Whale conveyor belt”, the migration across the oceans, whales move the mineral around, fertilizing the sea.
Climate Regulation
Nowadays, carbon footprint, the release of carbon dioxide (CO2) into the atmosphere, affects our ecosystem and lives. CO2 is the most impactful pollutant gas, and it contributes to global warming through the so-called greenhouse effect.
Recent studies have found that whales are able to absorb huge amounts of carbon dioxide. It is estimated that a single cetacean accumulates in its body around 33 tons of CO2 each year, far more than the 21 kilos of a single tree. The average lifespan of a whale is very long and can easily reach 90 years; it becomes clear how important these massive marine animals are for maintaining the right CO2 balance in the Earth’s atmosphere. Furthermore, when whales die, the “whales fall” leads to organic carbon accumulation at the bottom of the sea.
In a study from 2019, the increase in whale population is considered a low-tech solution to reduce the amount of CO2 in the atmosphere; a long-term strategy to protect whales could limit greenhouse gasses and global warming. These animals would be the most natural and cost-effective solution to climate change. It is supposed that the entire ecosystem of a whale absorbs 40% of all the carbon dioxide produced in the world, corresponding to four Amazonian forests.
Beyond that, as already mentioned, it seems that whales have an important impact on the abundance of phytoplankton. Phytoplankton are tiny organisms that inhabit the oceans, and they are crucial for marine and atmospheric environments, contributing at least 50% of all the oxygen in our atmosphere and they capture about 40% of all the CO2.
Conclusion
Sadly, after decades of illegal whaling, biologists estimate that global whale populations are now less than one-fourth of what they once were.
A study published in November 2020 in Endangered Species Research shows that some of the most endangered cetacean species are slowly returning to their original habitats, particularly in the polar regions. However, there are new challenges, such as the glaciers melting due to global warming or the increased shipping traffic, that make it necessary to develop new strategies for the conservation of these majestic mammals.
Therefore, the benefits of whale ecosystem services to us and our survival are far less than they could be. If the number of whales could be restored, the impact on ocean balance and climate change could be massive.
Help us Help Them! Think Wildlife Foundation is a non profit organization with various conservation initiatives. Our most prominent campaign is our Caring for Pari intiative. Pari is a rehabilitated elephant at the Wildlife SoS Hospital. 25% of the profits from our store are donated to the elephant hospital for Pari. Other than buying our wonderful merchandise, you could donate directly to our Caring For Pari fundraiser.
Written by: Federica Scala