Two sterlet meat samples purchased in restaurants along the Danube showed strong indications of wild origin. The survey also identified shortcomings in caviar labelling, weaknesses in traceability and misleading information provided to consumers.
More than half of the sturgeon products tested in Bulgaria were found to have issues. This is one of the findings of WWF’s “TRANSPARENT STURGEON” report, published in October 2026, which examines compliance, traceability and illegal trade in the European sturgeon market.
The findings raise an important question for sturgeon conservation: how effectively can trade controls establish the actual origin of the caviar and meat being sold and prevent products from wild sturgeons from entering the market?
The survey covered Bulgaria, Romania, France, Germany, Italy and Switzerland. Between April 2024 and March 2025, a total of 158 samples — 133 caviar samples and 25 meat samples — were collected from restaurants, specialist shops, supermarkets and online platforms. Meat samples were included only in Bulgaria and Romania because of the two countries’ importance for wild Danube sturgeons and the risk of illegally caught fish being sold on domestic markets.
Three complementary methods were used: genetic analyses to identify species, isotope analyses to assess aquaculture or potential wild origin, and physical examinations of packaging and labels.
In Bulgaria, 25 samples were tested — 14 caviar samples and 11 meat samples. The results showed:
- 12 samples, or 48%, with no detected irregularities;
- 10 samples, or 40%, with one or more violations of requirements under CITES, the convention regulating international trade in endangered species;
- a further 3 samples, or 12%, with misleading species declarations but no detected CITES violations.
In total, 13 of the 25 samples — 52% of the Bulgarian sample set — had an identified issue. These percentages describe the specific products tested and should not be extrapolated to the entire Bulgarian market.
The most concerning finding for Bulgaria involved two sterlet (Acipenser ruthenus) meat samples purchased in restaurants along the Danube. According to the report, isotope analyses indicated a probability of wild origin exceeding 99%. This is a strong indication that wild sturgeons may continue to be offered for sale despite the ban on their capture and trade cited in the report.
WWF notes that similar findings were recorded in previous surveys. One of the restaurants appeared in both the current and an earlier study. In the present survey, a beluga sample from that establishment was assessed as originating from aquaculture, while a sterlet sample showed characteristics consistent with wild origin.
The sale of aquaculture products alongside products of likely wild origin makes inspections more difficult. As the report explains, documentation for legal purchases may conceal the occasional sale of illegally sourced fish. This highlights the importance of laboratory analyses alongside checks of documentation.
Several types of shortcomings were identified in the caviar purchased in Bulgaria:
- two samples lacked CITES labels;
- two samples carried incorrect species codes;
- six samples showed labelling deficiencies, primarily labels that could be removed.
These categories may overlap: a single product can have more than one issue.
Labelling is directly relevant to traceability. The CITES code provides information on the species, source, country of origin and other product characteristics. When a label is missing, contains incorrect information or can be transferred to another container, the reliability of verification is weakened.
The report also examines the international dimension of these problems. Products with irregularities linked to three registered Bulgarian caviar processors were identified both in Bulgaria and in France. All five tested products linked to one of these processors showed deficiencies in CITES labelling and/or coding.
Similar violations were detected in all six countries. Overall, 82 of the 158 products tested — 52% — showed at least one issue. The findings varied in severity, ranging from shortcomings in label attachment and inaccurate species declarations to strong indications of wild origin.
WWF recommends more frequent inspections throughout the supply chain, systematic use of genetic and isotope analyses, and better information exchange between the competent authorities. Particular attention should be given to operators with recurring violations and to online sales, where the origin of products and the identity of sellers can be difficult to establish.
For consumers, the practical takeaway is to seek clear information about the species and origin of sturgeon products. For caviar, a legible CITES label is an important element of traceability, while WWF’s findings show why checks must also establish the accuracy of the information provided.
The conservation of wild sturgeons also depends on what reaches shops, restaurants and online platforms. Reliable traceability and effective enforcement are essential parts of efforts to conserve these fish in the Danube and the Black Sea.
Source: WWF, October 2026, “TRANSPARENT STURGEON — Compliance, Traceability Issues and Illegal Trade in the European Sturgeon Market”. The findings for Bulgaria are presented on pages 12–13, with the comparative analysis and recommendations on pages 14–19.
Illustrative photograph: Parviz Hajizada / Pixabay.