SURGEONFISH ‘DORY’ RETURNS FROM FORCED CANNIBALISM TO ITS NATURAL HERBIVORE STATE
Worldwide herbivorous fish in aquaria are fed with fish food which contains high amounts of animal ingredients. As this is not a healthy matter, Rotterdam Zoo decided to make their own, more natural, diet for the herbivorous fish in the aquarium. The main focus is raising the welfare standards of the fish.
Ingredients in fish feed
The fish food currently available for marine herbivorous fish in aquaria differs from the diet of their relatives in the wild. All over the world, these fish are fed with food based on animal ingredients, like fishmeal. The vegetable ingredients in these feeds are agricultural products, such as corn, wheat, soy and other beans, instead of aquacultural products. This is quite strange. Consequences of this diet mismatch for fish health is practically unknown, but an adequate diet could at least suppress diseases like Head and Lateral Line Disease.
100% vegan and aquacultured
In this new food we leave out the animal and agricultural products. It is solely made of aqua cultured products. These adjustments in our fish diet are a step in the right direction to a more natural diet for herbivorous fishes. Furthermore it is a good method to avoid the unsure base of fish material and vegetables in our current fish meal and food.
Most herbivorous fish are ‘grazers’. Surgeonfish for example (known as `Dory` from the Disney movies), eat algae that coat the hard surface on reefs. This natural grazing behaviour is also promoted in our Oceanium. Our fish food is not bound with commonly used gelatine of animal origin but made with agar which is made of red and brown seaweed. In liquid form we spread the food over our artificial corals. This ensures us the fish can show their natural grazing behaviour. For other fish in these tanks it is harder to get this food because their beaks are not suitable to scrape or pull the feed. This ensures that the herbivorous fish graze for longer periods as they would do in their natural habitat. In the `Coral tunnel tank` of our Oceanium there is a diversity of herbivorous fish like surgeonfish, spotted scats, bannerfish and batfish.