As a new project partner, the Haus des Meeres has transformed a 13 000 liter aquarium into a Danube basin. Juvenile sturgeons are being raised here to serve as future broodstock, helping to sustain the sturgeon population in the Danube.

Bob Kreiken, a nature and biology enthusiast from the Netherlands, embarked a two-month expedition of 3.500 kilometers across Europe, along the Rhine by bicycle and Danube by kayak.

The Danube River Basin was formerly home to six sturgeon species, namely beluga, Russian, stellate, ship, European sturgeon and sterlet. All are highly endangered or, in in the case of ship and European sturgeon, already extinct in the Danube. In the past these ancient fish migrated nearly 2000 km from the Danube Delta to Vienna to spawn, a journey undertaken for millions of years.

With the largest mobile aquarium in Europe placed in the heart of Vienna from June 21st to 23rd, attention was drawn to the precarious situation of the sturgeons and the importance of preserving and protecting the unique habitat of the Danube.

The sturgeons from the project are stocked in various sizes to maximize survival rates, starting at sizes below 1 cm. The last batch of the 2023 year class was released at the end of February with an average size of 25 cm, equipped with PIT and color tags.

Sturgeons are the world’s most endangered group of animals. Two of the six sturgeon species that previously inhabited the Danube River Basin have already become extinct in the area.

This year a total of 35.380 sterlets were released into the Austrian Danube and tributaries. A couple hundred individuals are still in the hatchery and are kept for further reproduction and the living genetic databank.

In October, a mural action took place on the New Danube in Vienna under the project management of the University of Natural Resources and Life Sciences Vienna. Children from the mentoring organization younus created a mural with the artist RoxS. To create awareness for the precarious situation of the sturgeons, juvenile fish were also released into the Danube.

One important part of the LIFE Boat 4 Sturgeon project is the establishment of a standardized Danube-wide population monitoring for all four sturgeon species. In order to target different age classes, it is necessary to use different methods.

Each year, Danube Day invites around 79 million people in the 14 Danube countries to partake in a beautiful joint celebration and outdoor events throughout several Danube countries! Established in 2004, Danube Day has been an opportunity to commemorate the anniversary of the signing of the Danube River Protection Convention on 29 June 1994 in Sofia, Bulgaria and celebrates the Danube and its tributaries and their vital role in providing water, food, power, recreation, and livelihood.

One of the six rescue measures of the LIFE-Boat 4 Sturgeon project is the construction of a floating hatchery station on the Danube in Vienna.

A huge milestone was achieved at the beginning of May for the LIFE-Boat 4 Sturgeon project. After long preparations the team was finally able to obtain 21 mature beluga sturgeon (Huso huso) broodstock of Danube origin. The individuals were transported to a project facility in Hungary and will be tested for pedigree before being divided between locations in Austria and Hungary to minimize risks. Thereby, another step towards the projects conservation goals for sturgeons was made by creating the basis for a successful propagation of this endangered species.

The sterlet hatchery on the Danube Island in Vienna, which was built and operated in the previous project, was put back into operation in mid-April 2023. The larvae were already released in the Austrian Danube. This measure is intended to contribute significantly to the highly endangered population of this last sturgeon species that still occurs naturally in Austria. This allows a self-reproducing population to develop.