Save the underwater treasures

Coral reefs are among the most diverse and fascinating habitats in the world. But they are threatened by a range of stressors, including climate change, pollution, and overfishing. In the last thirty years, almost half of all coral worldwide has disappeared. That's why we are joining forces with the University of Amsterdam to conduct research on coral reef stress. Behind the scenes, in the laboratory of our Oceanium, there is a setup. Here, scientists analyze coral to understand their tolerance to heat and acidification. The goal is to better predict how coral reefs will respond to changes in their environment and how we can deal with them.

This collaboration is crucial because we are addressing a problem that affects all coral reefs worldwide. Currently, experts predict that if global climate warms by two degrees by the year 2100, 99% of all coral will disappear. This would have serious consequences for all underwater biodiversity. It is therefore crucial to investigate whether these predictions are accurate so that we can intervene better. The more we know about what is really going on, the better we can act.

In various oceans, seahorses hide among reefs, algae, and seagrasses. You can also find them along the Dutch coast. Here, for example, short-snouted seahorses live. Unfortunately, short-snouted seahorses are increasingly washing up on our beaches, undercooled and weakened.

Due to increasing climate change, more and more short-snouted seahorses live along the Dutch coast. Their habitat shifts because African waters are becoming too warm. In addition, due to their limited swimming ability, they have difficulty holding onto seaweed during stormy weather. The result: a growing number of stranded seahorses on our beaches.

This is where Blijdorp comes to the rescue. We shelter short-snouted seahorses in special tanks behind the scenes. The water is precisely warm and salty enough, and they are fed shrimps and given seaweed to hold onto and hide in. This way, they regain strength for the upcoming spring. When the seawater is warm enough again, a special diving team releases the seahorses back into the Eastern Scheldt. By releasing them, we contribute to the preservation of short-snouted seahorses!

Plastic pollution is a growing problem and poses a serious threat to all life in the seas, oceans, and beyond. Every year, tons of plastic waste end up in the oceans. Animals get entangled in plastic or ingest it. Plastic hardly decomposes but breaks down into minuscule particles: microplastics. These particles spread through the food chain and eventually end up on our plates. Plastic pollution, therefore, has consequences for both marine and terrestrial life.

Fortunately, there are glimmers of hope. To combat plastic pollution, we collaborate with organizations like The Ocean Cleanup. Their mission is not only to restore oceans but also to raise awareness about the urgency of this global problem. They develop innovative technologies to clean up. Diergaarde Blijdorp has provided facilities in the Marine Lab, behind the scenes in the Oceanium. Here, The Ocean Cleanup conducts research and tests new techniques. This way, the technology is optimized in a controlled environment, minimizing any unwanted side effects when applied in the wild.

By working together to find solutions, we ensure the protection of our oceans and preserve all the unique life forms of the magical underwater world, including those on land.

In an unexpected turn of events, multiple sea turtles have washed up on Dutch beaches in the autumn of 2023 and the winter of 2024. This is remarkable since it did not happen so often before.

With the official authorization to rescue and release sea turtles, Blijdorp provides these unexpected guests with a refuge. When a report comes in, for example, from hikers or fishermen, our team sets out. The animals, often weak and undercooled, are sheltered behind the scenes of the Oceanium. The veterinarian and animal caretakers work hard to nurse the animals back to health. Once they are strong again, they are prepared for return to their natural habitat.

During their stay at Blijdorp, the sea turtles are not only cared for but also studied. Scientists from the Vrije Universiteit Amsterdam, for example, study the mussels that were on some shells to eventually determine where the animals come from and which route they took before they washed ashore. With this knowledge, we can better prepare to rescue more sea turtles in the future and release them in the right place.

Rivers and streams are important habitats for many plant and animal species. Many fish, for example, use rivers to lay their eggs, then return to the sea. One such species is the iconic European sturgeon, a large migratory fish that swam in Dutch rivers until 1952. Unfortunately, the sturgeon died out in the Netherlands due to overfishing, poor water quality, and the construction of dams.

The water quality of our rivers has improved since then, and large dams, such as the Haringvliet Dam, are now slightly open. This allows migratory fish to return to their old spawning grounds. This applies, among others, to the European sturgeon. Together with organizations such as ARK Rewilding and WWF, Blijdorp is committed to reintroducing the sturgeon to Dutch waters.

Diergaarde Blijdorp is the only zoo in the Netherlands where you can admire the sturgeon. We consider it important to introduce people to this ancient giant. The sturgeons swimming in our Oceanium later depart for Germany to contribute to a breeding program for young sturgeons. Our partners then release these sturgeons back into Dutch rivers. When they are fully grown after about twelve years, they will hopefully return on their own to lay eggs again.

With a passion for species conservation and nature restoration and our dedication to protecting vulnerable habitats, we continue to work daily for the underwater treasures of rivers and ensuring a healthy future for these valuable waterways.