This study tested whether eutrophication could influence life‐history traits of a cyprinid, Chanodichthys erythropterus , in 10 Chinese lakes. Using the von Bertalanffy growth model, the asymptotic length ( L ∞ ) and the growth performance index ( I GRO ) were significantly affected by eutrophication. The gonado‐somatic index ( I G ) and relative fecundity ( F R ) were significantly lower in mesotrophic lakes than in eutrophic...

The intrinsic effect of feeding regime on survival and predation‐induced mortality was experimentally tested in genetically modified ( GM ) Cyprinus carpio and wild specimens. The results clearly indicate a knock‐on effect of the GH gene ( gcGH ) introduction into the C. carpio genome on their vulnerability to predation. The experiments unequivocally showed that it is the genetic nature of the C. carpio rather than its size th...

Contributions presented at the international NeoFishMed workshop on New Approaches for Assessing the Impacts of Non‐native Freshwater Fishes in the Mediterranean Region are reviewed. Rivers in Mediterranean‐climate regions are characterised by a dynamic hydrology, resulting in severe droughts during summer and flash flooding in winter. These types of systems, when disturbed by human actions, seem to be particularly suitable to...

The efficiency of individual genetic tagging was determined by using passive integrated transponders (PIT) as a comparative conventional tagging method. Fifty‐five common dace Leuciscus leuciscus were captured in the wild, PIT tagged and fin clipped (for DNA analysis). Thirty fish were recaptured on three occasions and tissue samples were collected. Using 18 microsatellite loci, 79–94% of the recaptures were correctly assigned...

Caves and karsts are among the most threatened ecosystems in the world. They are very fragile, balanced habitats with high levels of endemic species that are extremely sensitive to environmental changes. In recent decades, however, threats from rapid economic growth have increased the need for conservation efforts for cave‐dwelling communities. In addition, difficulties in accessing and sampling these habitats mean that they r...

In recent years, policy‐makers have sought the development of appropriate tools to prevent and manage introductions of invasive species. However, these tools are not well suited for introductions of non‐target species that are unknowingly released alongside intentionally‐introduced species. The most compelling example of such invasion is arguably the topmouth gudgeon Pseudorasbora parva, a small cyprinid species originating fr...

This review provides a contemporary account of knowledge on aspects of introductions of non‐native fish species and includes issues associated with introduction pathways, ecological and economic impacts, risk assessments, management options and impact of climate change. It offers guidance to reconcile the increasing demands of certain stakeholders to diversify their activities using non‐native fishes with the long‐term sustain...

The efficiency of portable passive integrated transponder (PIT) telemetry at detecting five fish species in a small river was evaluated under different environmental and tracking conditions. Significant differences between species were apparent, with detection efficiency varying between 0·7% ( Leuciscus leuciscus ) and 43·1% ( Salmo trutta ). Conditions of reduced flow and tracking in a downstream direction significantly incre...

Despite knowledge of potential adverse impacts arising from non‐native fish introduction, economic drivers are still pushing forward for further introductions. Gozlan's pragmatic approach to this neo‐paradox, allows using existing knowledge to characterise and discriminate ecological risks associated with fish species introduction. It confirms what many previously suspected, that the overall risk of adverse introduction is aro...

To assess the spatial variability in external morphology of non‐native populations of topmouth gudgeon Pseudorasbora parva within an ontogenetic context, triple regression analysis (distance‐based measurements) was applied to data from eight European populations (two Slovak, four Romanian, one English and one French). The data from Slovakia were also subjected to geometrical analysis (co‐ordinates‐based measurements) to obtain...

The hypothesis that vagility, or tendency to move, in pike Esox lucius can be predicted from individual home range was tested using telemetry. Independently of fish size, mean annual excursion distance was positively correlated to winter (0·02–0·95 ha) and spring (0·02–0·59 ha) home ranges but not summer and autumn home ranges.

The study of fish pheromones is particularly relevant because of the conserved nature of chemoreception in vertebrates. However, most fish pheromone systems remain unstudied. All the major known pheromones of freshwater fish and their associated behaviours were reviewed. Importantly, those studies that have demonstrated the connection between behaviour and pheromones in freshwater fishes have resulted in a wide range of applic...

In England, a severe decline of introduced sunbleak Leucaspius delineatus populations has been attributed to the introduction of the invasive topmouth gudgeon Pseudorasbora parva . In France, however, after 4 years of P. parva colonization in a large natural lake, no demonstrated impacts on the native L. delineatus populations have been observed. This suggests that the original impacts observed in England, such as spawning inh...

European countries in general, and England in particular, have a long history of introducing non‐native fish species, but there exist no detailed studies of the introduction pathways and propagules pressure for any European country. Using the nine regions of England as a preliminary case study, the potential relationship between the occurrence in the wild of non‐native freshwater fishes (from a recent audit of non‐native speci...

To address a lack of information on topmouth gudgeon Pseudorasbora parva introduced to watercourses, the microhabitat use of this non‐native cyprinid and co‐existing native species was assessed in a small stream located in southern England. Overall, microhabitat use was size‐structured and significant associations were observed between topmouth gudgeon and native species, including brown trout Salmo trutta , chub Leuciscus cep...

Since its first introduction to English waters in the mid 1980s, sunbleak Leucaspius delineatus has spread widely and it is shown in the present study that this non‐native cyprinid is a new host for Neoergasilus japonicus . This copepod parasite from South East Asia has a limited host range and distribution in the U.K. Rapid dispersal of sunbleak in the U.K. raises concerns for further dispersal of this introduced parasite.

Using the non‐native sunbleak Leucaspius delineatus as a model, the relationship between ontogeny and ecology was studied with a view to identifying specific morphological and physiological processes involved in influencing ecological niche shifts. Following a predefined saltatory model for the early ontogeny of sunbleak, field studies examined the temporal use of microhabitat, diet and morphological changes throughout early d...

The influence of early life development on the swimming performance of the endangered sofie Chondrostoma toxostoma was examined to highlight trends in organism‐environment relationships. Sudden occurrences of change in integrated function were found and these were most decisive, in particular with respect to microhabitat use, between the larval and juvenile periods of development. Stabilization of relative growth, i.e . end of...

The early development of sunbleak Leucaspius delineatus , from activation of ovum to juvenile, was recorded using both living and preserved materials. Five embryonic steps, one free embryo and five larval steps were identified. Hatching occurred between 73 h 25 min and 85 h 25 min (post‐activation); the free embryo period was extremely short in duration (3–16 h). The transition from larva to juvenile occurred in c . 96 days wh...

The spawning behaviour of male nest guarding sunbleak Leucaspius delineatus , a recent invasive species in southern England, was studied and quantified for the first time. In the absence of physical differences between territorial and non‐territorial males ( i.e . colour, size, etc .), the reproductive behaviour of territorial males was analysed and related to reproductive success. The results showed that females preferred hig...