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Don’t feed the fish!

By November 17, 2018August 24th, 2020Blog, Food for thought, PADI, Scuba, Underwater Life

There’s something fishy going on

Once of the best parts about island life is being surrounded by plenty of wildlife in the Ocean. Indonesia is extra special because of the diversity around the islands of Lembongan. Nusa Ceningan and Penida also share in this biodiversity. We love to take our guests diving and show them the aquatic life and underwater buddies we meet every day. Unfortunately, as the island becomes more popular, the number of people visiting increases. While this is good for tourism, it can have a down side for the local ecosystem.

The instant entertainment problem

What is this down side I hear you ask?
Not this time, though that is a problem too. I am, in this case, talking about the much more innocently seeming practice of fish feeding.
This blog actually came about because I was sitting at a local coffee shop and overheard a couple of new divers. They were talking about how the dive operator they chose was throwing food in the water to attract the fish. They thought it was amazing because fish surrounded them in a feeding frenzy. It seems so harmless so what’s the problem?
scissor tail sergeant being fed

A school of Scissortail Sergeant being fed.

Eating as nature intended

Whether it’s a local captain throwing a few biscuits in the water. Or a large scale operator with divers feeding fish in front of windows of glass bottom boats. It’s done to attract fish to the boat and entertain the tourists. Odd then, that a lot of people seem unaware that this is not only bad for the fish, but also the coral reefs as well.
Now before I go on, I’m not being a killjoy. When visitors to the islands were few, it made little difference. Now with so many daily, if not hourly visitors, you can see the change happening before your eyes.
fish feeding in St Thomas

This is an actual promo shot from a company advertising fish feeding.
(with dog biscuits!)

The fish don’t seem to mind so what’s the problem?

Sounds obvious I know, but like humans, fish need the right type of food in their diet. Croissants, chocolate biscuits or even slices of fresh fruit are bad. While delicious to us, they are not part of a fishes natural diet. Bread in particular is bad. It swells in the fishes stomach causing them to expand and suffer serious health issues. At best, they may get sick. At worst, they will die or a predator will take them as they unable to act in a natural manner.
As this unnatural food source becomes more common, it can cause a decline in some species. It can also cause an overpopulation in others.

Its not only the fish that suffer

Further, foods that don’t get eaten by the fish, fall to the ocean floor and pollute the reefs . Adding food to the water around reefs increases nutrient levels. This in turn, increases the growth of harmful algae that damage corals. Algae can and should be a natural food source and is normally eaten and removed from the reef. In fact, the majority of reef fish are grazers, meaning they only eat algae. They keep the growth of the algae on coral reefs under control so that the reefs aren’t smothered.
When we fish feed, their behaviour changes so that they no longer graze on the harmful algae. So, the algae doesn’t get removed. This results in the algae becoming overgrown. Over time, the reef will die and the habitat of many species will be lost as the reef is literally choked.
green reef
Beautiful reef

A reef with excess algae buildup, (from excess nutrients and warming), compared with how it should look… You decide.

(no copyright infringement intended)

Walking on the wild side

Ocean fish (and all wild animals) should be wary of interactions with humans. Though not always, our interactions with them tend to be detrimental to the animal involved. There’s an argument that any snorkeling or diving is affecting the animals behaviour. Sometimes this may indeed be true. So lets try to minimise our impact when interacting with these animals.

Diver and turtle

The kind of interaction we like. Let nature do it’s stuff.
(Incidentally, the turtle was THIS big!)

Let nature take its course

Feeding fish is conditioning the animals to associate humans with food. This affects the animals natural instincts. From the feeding cycles of famine and fast to giving predators a further advantage. ‘Tamed’ fish awaiting human interaction in one area are a great spot for a predatory lunch.
A healthy reef relies on competition for food and space. Old or sick fish will die while the strongest survive. While it may sound dramatic, in some cases, feeding the fish may allow weaker specimens to live longer. This can and does have a negative effect on the health of the environment.

Eat your own snacks

So next time you are on a dive or snorkel trip, be aware of the aquatic life. Remember not to throw that banana skin or handful of biscuits over the side. Aside from the general pollution it causes, the marine life really doesn’t need it.
Have you heard the Sirens Call
Darren Warburton

Author Darren Warburton

Aquatic bodyguard, chief tank filler and biscuit dunker.

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