In June 2011, 34 specimens of round goby (Neogobius melanostomus) were caught at three different locations in the Sava River in Croatia, which is a first record of this invasive species in Danube tributaries in Croatia. Size, structure and condition of populations indicate that the species is well adjusted to its new habitat and that further range expansions are highly likely.

The impacts of aquatic invasive species vary from the population to ecosystem level most strikingly through modifications native communities, often leading a decline in species. A primary impact mechanism is competitive displacement by resource partitioning. However, trophic interactions between and occupying same habitat remain poorly understood, particularly at early stages invasion. This stu...

The aim of this study was to assess the discriminability stocks round goby Neogobius melanostomus based on shape its otoliths. Recent otolith-shape-based species and stock discrimination studies were using otolith contours in sagittal plane we are following approach. We hypothesized possibility existence several geographically separated populations goby. Round gobies have been sampled from diff...

Alternative reproductive tactics are characterized by the occurrence of discrete alternative morphs that differ in behavioural, morphological and physiological traits within the same sex. Although much effort has been made to describe the behaviour, morphology and physiology of such alternative morphs, less effort has been invested investigating how much overlap there is in the characteristics ...

Studies of interactions between invasive and native species often focus on impacts on natives. We report potential impacts of a native predator, the Lake Erie Watersnake (Nerodia sipdeon insularum) on an invasive fish, the Round Goby (Apollonia melanostomus). Round Gobies have increased exponentially in the Great Lakes and now constitute >90% of prey consumed by Lake Erie Watersnakes. We invest...

III Lehtonen, T. K. & Lindström, K.: Sexual selection for body size is determined by the intensity of male-male interactions in the sand goby IV Lehtonen, T. K. & Lindström, K.: Females decide whether size matters: plastic mate preferences tuned to the intensity of male-male competition

Testicular histology of mature grass goby (Zosterisessor ophiocephalus) collected in Bizerta lagoon showed several types of histological lesions. A high prevalence of these lesions was detected in stations influenced by discharges of industrial and/or urban activities. These results highlight the reproductive disturbance of gobies from Bizerta lagoon.

Non-native invasive species are a major threat to biodiversity, especially in freshwater ecosystems. Freshwater ecosystems are naturally rather isolated from one another. Nonetheless, invasive species often spread rapidly across water sheds. This spread is to a large extent realized by human activities that provide vectors. For example, recreational boats can carry invasive species propagules a...