DOI: 10.3897/saddi.31.196822

Authors: Ümit Dokuzparmak, Ömerhan Dürrani

Abstract: The sharpsnout seabream, Diplodus puntazzo (Walbaum, 1792), is a demersal sparid that has recently established populations in the Black Sea, where the basin represents the northern margin of its known distribution. This study documents a new maximum size record for D. puntazzo in the Black Sea and provides an additional observation on its autumn feeding ecology. On 29 November 2025, a single female specimen was captured by spearfishing at 14 m depth over rocky substrate off Yomra, Trabzon, in the southeastern Black Sea. The specimen measured 47.6 cm in total length and weighed 1,452.0 g, exceeding the previously reported regional maximum total length of 45.4 cm and maximum body weight of 1,186.5 g. Although the increase in length was moderate, the substantially greater body weight may be partly associated with the specimen’s greater maximum body depth, rather than reproductive condition, as the gonads were not macroscopically prominent at the time of capture. Stomach content examination revealed only macroalgae, identified as Ulva rigida and Ceramium spp., indicating recent macroalgal ingestion during late autumn. This finding contrasts with previous summer observations of D. puntazzo feeding on egg capsules of the invasive veined rapa whelk, Rapana venosa, in the same region and may reflect seasonal dietary flexibility. The capture of a record-sized individual by spearfishing further suggests that large specimens encountered in recreational fisheries may be insufficiently represented in conventional fishery records; however, this inference remains preliminary due to the opportunistic nature of the observation and the single-specimen basis of the study. Overall, this record extends the known maximum size of D. puntazzo in the Black Sea and provides a useful biological reference for future studies on growth potential, trophic ecology, habitat use, and fishery interactions of this increasingly relevant sparid in the region.

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DOI: 10.3897/saddi.30.160476

Authors: Vasile Oțel, Aurel Năstase, Iulian Fomici

Abstract: In the period 2018–2024, new species of fish belonging to the order Siluriformes (silurids) were reported in the freshwater habitats of the Romanian part of the Danube Delta Biosphere Reserve (DDBR). These species were: Ameiurus melas (black bullhead) and Ictalurus punctatus (channel catfish), which are both American catfish species belonging to the Ictaluridae family, as well as Clarias gariepinus and its hybrid, Heteroclarias (North African catfish, a cross between Clarias gariepinus and Heterobranchus longifilis, belonging to the Clariidae family). These two American catfish species have been present in the DDBR for several years, following the first recorded appearance of the species in Romanian freshwater upstream of the Danube Delta. However, the North African catfish (Clarias gariepinus and the C. gariepinus × H. longifilis hybrid) should not be included in the list of alien species in the DDBR because they appeared accidentally in the DDBR and cannot withstand the low water temperatures in temperate zones during winter. The DDBR’s list of alien freshwater fish already includes seven species, such as Hypophthalmichthys molitrix, H. nobilis, Ctenopharyngodon idella, Pseudorasbora parva, Perccottus glenii (all five fish species are native to Asia) and Lepomis gibbosus (native to North America), as well as an extension of the range of Percarina demidoffi. Records of alien silurids confirm that two other alien fish species on the DDBR list have spread by natural dispersal from Romanian waters to the Danube Delta. Monitoring activities in the area should continue in future studies to observe possible numerical expansion and assess the impact of alien silurids on native species. For now, only Ameiurus melas raises concerns about its negative impact on native ichthyofauna.

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