Abstract Jansen, H. M., Winter, V., Bruijs, M. C. and Polman, J. G. 2007. Just go with the flow? Route selection mortality during downstream migration of silver eels in relation to river discharge. – ICES Journal Marine Science, 64: 1437–1443. The European eel (Anguilla anguilla) has been steep decline for several decades. Fisheries hydropower-induced presumably play an important role eels, downstream-migrating must make various navigation route-selection decisions reach sea. We examined...

Abstract – European eel Anguilla anguilla is in strong decline. We assessed the relative impact of fisheries and hydropower during downstream migration silver River Meuse Netherlands using radio‐telemetry. For this, 16 fixed detection stations (Nedap Trail‐System ® ) were used, each covering entire river width, including all outlets to sea, two entrances present. In September 2002, 150 eels surgically implanted with Nedap‐transponders released at catch site. Of these, 121 started migrate...

In view of the rapid extension offshore wind farms, there is an urgent need to improve our knowledge on possible adverse effects underwater sound generated by pile-driving. Mortality and injuries have been observed in fish exposed loud impulse sounds, but levels at which (sub-)lethal occur limited for juvenile adult fish, virtually non-existent eggs larvae. A device was developed larvae can be sound. It consists a rigid-walled cylindrical chamber driven electro-dynamical projector. Samples...

Subsea power cables cause electromagnetic fields (EMFs) into the marine environment. Elasmobranchs (rays, skates, sharks) are particularly sensitive to EMFs as they use electromagnetic-receptive sensory systems for orientation, navigation, and locating conspecifics or buried prey. Cables may intersect with egg laying sites, mating, pupping, nursery grounds, foraging habitat migration routes of elasmobranchs effects encountering on species largely unknown. Demonstrated behavioural attraction,...

1. Large river floodplains are considered key nursery habitats for many species of riverine fish. The lower Volga River (Russian Federation) still relatively undisturbed, serving as a suitable model studying the influence flooding and temperature on fish recruitment in floodplain rivers. 2. We examined interannual variability success young-of-the-year (YOY) relation to flood pulse characteristics rising water temperatures spring. sampled four areas with different regimes, three consecutive...

Abstract Offshore activities elevate ambient sound levels at sea, which may affect marine fauna. We reviewed the literature about impact of airgun acoustic exposure on fish in terms damage, disturbance and detection explored nature assessment population level. provided a conceptual framework for how to address this interdisciplinary challenge, we listed potential tools investigation. focused limitations data currently available, stressed benefits from cross‐species comparisons....

Abstract Grey mullets (family Mugilidae ) are widespread across coastal, brackish, and freshwater habitats, have supported fisheries for millennia. Despite their global distribution commercial value, little is known about movement ecology its role in the co-existence of sympatric mullet species. Gaps knowledge migratory behaviour, seasonal occurrence, scales also impeded effective management, highlighting need further research. This study aimed to identify key habitats timing grey presence...

Subsea power cables are expanding in number and capacity due to increasing demand transport offshore generated energy. Energy transported through a cable creates an electromagnetic field (EMF). Elasmobranchs dependent on their perception of the earth's magnetic biologically induced electric fields, for orientation, navigation, locating conspecifics detecting prey. EMF levels from subsea will add natural signals potentially disrupting elasmobranch perception, but effects not fully understood....

Growth rates are generally obtained from back‐calculation of increments otolith readings and based on the assumption that mean annual growth can be scaled directly to distance between age rings. Although otoliths continue grow even when somatic ceased. To analyse yellow eel, a passive integrated transponder (PIT) mark‐recapture study was performed in four water bodies (Delfland, Markiezaatsmeer, Süderpolder Vinkeveense Plassen) Netherlands. PIT‐tags were used as an alternative method instead...

Summary 1. Floodplains are a key habitat for foraging, spawning and as nursery many riverine fish species. The lower Volga floodplains (Russian Federation) still relatively undisturbed, while in Europe North America, about 90% of have effectively been lost. 2. We examined relationships between the extent timing spring flood, lateral movements species duration floodplain by sampling during 2006 2007. 3. Only rheophilic species, that released their eggs floodplain, coincided with flood. In...

ABSTRACT Periodic flooding plays a key role in the ecology of floodplain rivers. Damming such rivers can disturb patterns and have negative impact on commercial fish yield. The Volga River, largest river Europe, has regulated flow regime after completion cascade dams. Here, we study effects damming long‐term discharge variability flood pulse characteristics. In addition, evaluate altered ecosystem functioning yields. Our results indicate that both populations Volga–Akhtuba varied...

The "BIO-Sulfex" biofilter of ATZ-EVUS removes hydrogen sulfide from biogas in a biological way. Hydrogen causes massive problems during power generation plant, e.g. corrosion engines and heat exchangers, thus frequent therefore expensive engine oil changes. BIO-Sulfex module is placed between the digester power-plant warrants cost-effective, reliable fully desulfurization. In cleaned gas concentrations less than 100 ppm can be achieved. Power-plant manufacturers usually demand 500 or 200...

Abstract Winter, H. V., Jansen, M., and Breukelaar, A. W. 2007. Silver eel mortality during downstream migration in the River Meuse, from a population perspective. – ICES Journal of Marine Science, 64: 1444–1449. The European (Anguilla anguilla) has decreased sharply over past few decades owing to combination many factors. To determine impact hydropower fisheries silver telemetry experiments were performed years 2002–2006, using 18 detection stations (NedapTrail-System®) river two at...

River-floodplain systems are amongst the most productive—but often severely impacted—aquatic worldwide. We explored ecological response of fish to flow regime in a large river-floodplain system by studying relationships between (1) discharge and inundated floodplain area, with focus on spatial temporal patterns lake connectivity, (2) flood volume fisheries catch. Our results demonstrate non-linear relationship inundation considerable hysteresis due differences drainage rate. Inundation...

Coastal habitats serve essential roles in the life cycles of migratory fishes, impacting both local and regional population stability. Conservation efforts for coastal fish often rely on spatial approaches within designated boundaries to mitigate threats enhance production. However, open environments, behaviours can extend beyond these protected areas, exposing individuals potential or bottlenecks elsewhere their range. To improve conservation outcomes, a comprehensive understanding...

Abstract Range tests play a critical role in designing acoustic telemetry studies, guiding equipment configuration, deployment techniques, and the analysis of animal movement data. These studies often strive to capture effects environmental variation on detection efficiency over time but are frequently limited spatial temporal scale. This could lead disparities between test results circumstances encountered during tracking studies. In this study, we evaluated range at two distinct scales...

Abstract Large‐scale migratory patterns of adult rheophilic fish [barbel, Barbus barbus (L.), chub, Leuciscus cephalus ide, idus nase, Chondrostoma nasus (L.)] were studied in relation to habitat quality and possible migration barriers the lower rivers Meuse Rhine, Netherlands, using a telemetry system with transponders detection stations based on inductive coupling. Most moved over short distances (<10 km), especially those residing river stretches high diversity year‐round. About 16%...

The anadromous fish species North Sea houting, Coregonus oxyrinchus (L.), became extinct in the River Rhine (Kranenbarg et al. 2002) and many other rivers draining to 1940s (Lelek 1987).The cause was believed be a combination of overfishing, poor water quality, habitat loss fragmentation barriers hampering upstream migrations (De Groot & Nijssen 1997).Since 1980s, quality has greatly improved, migration were facilitated with fishways Leeuw 2005) no commercial fisheries on houting existed...