Article by: Nicola' Aguis, SOK Student
Many people perceive sharks as absolutely terrible species with large piercing teeth which destroy anything they want; however, the reality is far different. Just like other top predators, they keep a healthy balance in the ecosystem and this is why shark conservation measures need to be taken. What will we do when there are no more sharks left?
Sharks as predators
Predation is a density-dependent factor that occurs when a predator catches, kills and consumes a prey. For example, sharks that feed on a specific fish species that are slow and unable to hide are usually regulating the fish population. Like any other predator, the shark community ensures to remove those organisms in their food chain who are weak or sick to keep balance with competitors helping to ensure species diversity. Studies are already indicating that regional elimination of sharks can cause disastrous effects including the collapse of fisheries and the death of coral reefs. They provide one third of our world with food, produce more oxygen than the rainforests combined, remove half of the atmosphere’s anthropogenic carbon dioxide, which is a greenhouse gas, and so controls our planet’s temperature and weather (Oceana, 2016)
Can an ecosystem survive without sharks?
Like in every other food chain, there would be disastrous effects if the number of one species decreases or worse, ceases to exist. A study was carried out in Australia which indicated that when sharks were removed from an ecosystem, oxygen quantities in our atmosphere would decrease. This is because when algae die, they use oxygen in the water to decompose, hence limiting the amount of oxygen for other life in the ecosystem (Operation Apex Harmony, 2015). Thus, fish which consume algae are of utmost importance as they eat the algae before it dies. With no sharks, fish like snappers would increase since they were predated by sharks and they would in turn predate on algae-eating fish.
Sharks survived the five mass extinctions but are they going to survive the wrath of humans?
Sharks have been living and evolving for about 450 million years. They have survived the five mass extinctions including that which lead to the dinosaurs’ demise however, can they survive humans’ wrath of for example overfishing or shark finning? According to the International Union for the Conservation of Nature, 64 out of 400 known species of sharks are endangered, these include the Angel Shark (Squatina squatina) which was once abundant all around the coasts of Western Europe and the Daggernose Shark (Isogomphodon oxyrhynchus) (IUCN, 2014).
How to help in the conservation of sharks
It would be a shame to lose these species from the face of the Earth forever. There are multiple ways by which one could help out, some being; spreading awareness, joining an organisation, being smart when eating sea food, buying fish which are caught without risking sharks, and not buying shark products.
Unfortunately, the shark population is on the decline and so the risk of endangerment continues to increase. The importance of sharks in the ecosystem is still prominent, even in the Maltese ecosystem, and it is for this reason that we must help in the conservation of sharks by the mentioned ways (Shark Angels, 2015)
There are so many great things that you could do and as I write this, my mind is bursting with ideas. So, here's a list and I hope it will help you :)
The list is endless so if you have any ideas, please get in touch. We are happy to hear more from you.