The black bullhead is an invasive species that forms dense populations and has a negative impact on the native ichthyofauna. Recent studies indicate that it is one of the most dominant invasive fish species in Serbian waters. Feeding habits based on stomach contents of individuals caught in Lake Sava were analyzed as a first step towards evaluating its possible negative impact on the native fish fauna of the lake. The following indices for diet analysis were applied: vacuity index, frequency of occurrence, numerical abundance and prominence value. Trophic niche breadth and seasonal trophic diversity were calculated using the Shannon?s index. The diet spectrum comprised 16 different prey categories from five groups: Mollusca, Crustacea, Insecta, Teleostei and plants. Fish were the main prey in all seasons, followed by aquatic invertebrates. Plant material and terrestrial insects were used as food in relatively small quantities. Predation on fish eggs was also detected. Our research confirmed that this species is an opportunistic generalist. An ontogenetic diet shift was also detected. The lowest value of trophic diversity was found in age 1+ individuals (H=1.39), while the highest was found in age 3+ individuals (H=2.00). The widest niche breadth was recorded in spring 2011 (H=2.12).

This study explores the potential of utilizing black bullhead (Ameiurus melas Rafinesque, 1820), an invasive freshwater species, as a stocking fish for aquaculture. Fish were mass-removed from Ponjavica Nature Park during two periods (2018–2019 and 2020–2021), with selected individuals reared to evaluate growth, survival, and meat quality. A total of 20,145 individuals were removed in the first period (168 reared), and 15,921 in the second (120 reared). Two rearing systems—cages and recirculating aquaculture systems (RAS)—and four feed types were tested. Results demonstrated the species’ adaptability to intensive aquaculture, with good growth, resilience to high-protein diets, and tolerance to high stocking densities. Cage systems generally showed superior growth performance, while RAS produced higher survival rates. Both systems achieved favorable feed conversion ratios. Meat analysis revealed optimal levels of polyunsaturated fatty acids (PUFAs) in RAS and cage-reared fish, enhancing the species’ nutritional value for human consumption. These findings demonstrate the feasibility of repurposing black bullhead as a sustainable aquaculture resource. This dual-purpose approach addresses ecological concerns while offering economic benefits through increased fish production and affordable, nutritious food availability. Further technological development is needed to optimize production systems for broader implementation.

In recent decades, the Amur sleeper (Perccottus glenii) is one of the most impressive east-to-west invaders of European inland waters, but there are insufficient data on its biology in the countries it has entered. Specimens of two sets of samples from November 2015 (n=25) and October 2016 (n=39) were caught in the Danube River channel near Veliko Gradiste (Serbia) by electrofishing. Thirty morphometric and eight meristic characteristics of the collected fish were measured with the aim of describing the general body shape in more detail using the ?point-to-point? method. This is the first attempt to obtain morphometric and meristic characteristics of Amur sleeper caught in Serbia. The results revealed a relatively low variability in the morphometric and meristic characters of the studied population. When compared to other studies, there was a great variability of the studied characteristics between geographically distant European populations that inhabit different water body types. Female fish had more robust bodies compared to males of the same length, while males had longer pectoral, anal and dorsal fins. Additionally, 2+ individuals had more robust heads and jaws, as well as longer anterior parts of the body compared to 1+ individuals of the same size

This study aims to evaluate the black bullhead Ameiurus melas, an invasive alien fish (IAF) in Serbia, as a bioindicator organism and assess the safety of natural and aquaculture specimens for human consumption. A set of biomarkers was analysed to assess the bioindicator potential at a site exposed to agricultural activities. The genotoxic response was determined by an alkaline comet assay and micronucleus assay in fish erythrocytes, and the metal pollution index (MPI) was calculated to assess the toxic element burden on fish. Water quality was evaluated using physicochemical parameters and faecal indicator bacteria, while sediment was analysed for the presence of pesticides. The concentration of metals and metalloids in fish muscle was monitored to assess the safety for human consumption, and the corresponding indices (MAC, THQ, HI) were calculated. All biomarker responses were linked by the integrated biomarker response (IBR). Water analyses indicated the absence of communal wastewater, while sediment analysis revealed the presence of paclobutrazol, bifenthrin, and cyfluthrin. The IBR showed that June and September had the highest stress indices, coinciding with peak pesticide use and precipitation. All indices confirmed the safety of black bullhead for human consumption. This study highlighted the uses of nature-based solutions to the problem of IAF.