The oceans are one of the main reserves of biodiversity in the world. They make up more than 90% of the planet’s habitable space and contain 250,000 known species and many more yet to be discovered.
Healthy oceans are critical to the healthy functioning of the planet, as they supply half of the oxygen we breathe and absorb a large portion of the anthropogenic carbon dioxide emissions emitted into the atmosphere.
Therefore, maintaining the balance of marine ecosystems is very important. For this, it’s necessary that the marine food webs function correctly. All species are equally necessary. However, there are some whose absence can have more rapid and drastic effects. This is the case with sharks. As top predators in food chains, they regulate the populations of their prey. Without sharks, the populations of other species would multiply and excessively prey on other species causing an imbalance in the marine ecosystem.
“Without sharks, the populations of other species would multiply and excessively prey on other species until causing an imbalance of the marine ecosystem.”
What are some interesting facts about sharks?
Sharks don’t have bones.
- They are known as “elasmobranchs”, which translates into fish made of cartilaginous tissues. Their cartilaginous skeletons are much lighter than true bone and their large livers are full of low-density oils, both helping them to be buoyant.
Sharks have special electroreceptor organs.
- Sharks have small black spots near the nose, eyes, and mouth. These spots are the ampullae of Lorenzini, which allow sharks to sense electromagnetic fields and temperature shifts in the ocean.
Sharks are one of the oldest species on the planet.
- Fossil records show that they were cruising our oceans at least 400 million years ago. They have survived massive extinctions and evolved into many different species.
What are some of the misconceptions surrounding sharks?
We believe that sharks are attracted to human blood and attack when they detect it.
False. Although sharks can detect scents from miles away, humans are not part of their diet, and we do not smell like food to them. Every year there are less than 10 fatal shark attacks in the world, an insignificant number compared to deaths caused by other animals such as dogs.
Many people think that sharks have to eat constantly.
False: if they get a prey that gives them enough energy, they can go days without eating.
Sharks biggest threats
Despite being on the planet for more than 400 million years and having survived massive extinctions, sharks are reaching their limit: some of their populations have decreased by more than 90% during the last decades. There are many threats that are causing this situation. The main problem is overfishing, followed by the degradation of coastal habitats where they breed or feed, and, of course, marine pollution.
“Sharks are reaching their limit: some of their populations have decreased by more than 90% during the last decades.”
Sharks have certain characteristics that make them very vulnerable: they reach sexual maturity very late, have long gestation periods, and generally have few young. This is because, being predators, it would not be good for the balance of ecosystems if there were too many of them.
Using technology to address threats and spread awareness
Communication is the most powerful tool for marine conservation. Of course, science is an essential tool, but we must not limit it only to the scientific field, but rather it is important to bring knowledge to all audiences, in a universal language. Past generations did not have the access to information that we now have thanks to technology.
In addition, all the scientific procedures that I carry out as a marine researcher require technology. From the tags that we put on the sharks to locate them, to the processing of data obtained in the laboratory.
Small steps to protect and #savethesharks
In the same way that movies managed to create an idea about sharks in our minds and made us fear them, now we have the mission to demystify that erroneous image we have of these incredible animals. We can all make small changes in our day-to-day towards a more sustainable life. Some changes are uncomfortable and involve a longer path to achieve certain goals. But we only have one planet, one home, so it’s worth taking care of.
- Spread awareness about sharks and the importance of their conservation.
- Do not consume products that contain shark.
- Share initiatives that promote the conservation of sharks and donate to projects and NGOs.
“We only have one planet, one home, so it’s worth taking care of.”