5 Things you Might Not Know About Fish Feeding

September 30, 2019 Giacomo Abrusci, SEVENSEAS Media Editor-in-Chief Stories from the Sea, Sustainable Travel

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One of the amazing things about snorkelling is being surrounded by so many beautiful, brightly coloured tropical fish. To encourage the fish to come a little closer, some people might throw bread or food scraps into the water. But did you know feeding the fish is actually harmful to them and their environment?

On behalf of the team at The Reef-World Foundation, here are five things you might not know about fish feeding:

Fish feeding is damaging to the natural balance of the ecosystem

Marine ecosystems are all connected. So, feeding the fish – which is also dangerous to the health of the fish too – can disrupt the natural balance of the ecosystem. Through the simple act of fish feeding, you’re changing natural behaviours which can lead to the destruction of coral reefs and the incredible marine life they support. When a diver or snorkeller feeds bread, rice or food scraps to the fish, reef fish rush to them to try and get a nice bite to eat. But when species that are usually solitary show this type of group predatory behaviour, they leave their territory and nests unguarded and vulnerable to predators.

Fish feeding can lead to starvation

It might sound strange but being fed by humans could lead to fish starving to death. That’s because most marine animals have a very specific diet and a very specific range of digestive bacteria. If they’re fed the wrong food, the wrong type of bacteria can become dominant in their stomachs meaning they’re no longer able to digest their natural food and could starve to death.

Algae smothers the coral

Many fish normally eat algae; helping to control its growth. When they are fed by humans, the algae no longer has the fish to control is growth and may spread too quickly, smothering and suffocating the coral and causing it to die.

Crown-of-Thorns sea stars can grow out of control

Many divers have seen the catastrophic effects of a Crown-of-Thorns outbreak decimating the reef. These sea stars are natural predators of coral but, normally, fish grazing upon algae accidentally eat the eggs of Crown-of-Thorns and other coral predators; keeping them in check. When fish are being fed and stop grazing, predator populations can increase and damage the reef.

Throwing your lunch scraps overboard can be a problem too

You know the feeling: you’ve finished a great morning’s diving, had your fill of a delicious lunch and now you’re dozing in the warm sunshine. The crew are preparing to head back to the dive shop: collecting everyone’s tupperwares, tossing the scraps overboard and starting the engines to head back to shore. But throwing scraps overboard – even if your intention isn’t to draw in the fish – can have the same effect. Rather than throwing any leftovers, fruit peels or other food into the ocean, it’s best to collect all your scraps and take them back to the shop where they can be composted or disposed of responsibly.

The Reef-World Foundation leads the global implementation of the UN Environment’s Green Fins initiative, which focuses on driving environmentally friendly scuba diving and snorkelling practices across the industry globally. To keep up with our latest news and developments, please follow Reef-World on Facebook, Instagram and Twitter. You can also follow the Green Fins initiative on Facebook, Instagram and Twitter to keep up to date with new materials, updates and sustainability insights from Green Fins members.