Investigating patterns of genetic variation in hybridizing species provides an opportunity to understand the impact of natural selection on intraspecific genetic variability and interspecific gene exchange. The Atlantic eels Anguilla rostrata and A. anguilla each occupy a large heterogeneous habitat upon which natural selection could differentially shape genetic variation. They also produce via...

The morphodynamic changes occurring during growth were evaluated in the eel (Anguilla anguilla L.) heart. Using an in vitro working heart preparation, cardiac performance of small (body mass 96.76 +/- 27.49 g; mean +/- s.d.) and large (body mass 656 +/- 12 g; mean +/- s.d.) eels was compared under basal conditions and under loading (i.e. preload and afterload) challenges. A parallel morphometri...

To determine the importance of glucocorticoids in the salt water adaptation of European yellow eel we have evaluated the concentration, affinity and physical properties of glucocorticoid receptors (GR) in gill from both sea water- (SW) and freshwater-adapted (FW) animals. Using ligand binding techniques we demonstrated that high affinity GR were present in both cytosolic and nuclear fractions o...

Anguillicola crassus is a swim bladder nematode of eels. The parasite is native to the Asian eel Anguilla japonica, but was introduced to Europe and the European eel Anguilla anguilla in the early 1980s. A Taiwanese source has been proposed for this introduction. In the new host in the recipient area, the parasite appears to be more pathogenic. As a reason for these differences, genetically fix...

Otolith microchemistry is widely used as a tool to track individual migration pathways of diadromous Wsh under the assumption that the elemental composition of Wsh otoliths is directly inXuenced by the physicochemical properties of the surrounding water. Nevertheless, several endogenous factors are reported to aVect element incorporation into Wsh otoliths and might lead to misinterpretations of...

To gain information about the relative proportion of introduced anguillid eel species inhabiting Japa nese natural waters, 98 eels were collected and genetically identified — 46 from the Uono River, Niigata, Japan, during their downstream spawning migration, and 52 silver eels from the East China Sea. Species identification using RFLP analysis of the mitochondrial 16SrRNA domain suggested that ...

Comparatively little work appears to have been done on the circulation in the intact living fish, particularly in the bony fish. This paper describes the circulation in the common eel using angiographic methods. This species is convenient as it can be fairly easily obtained in the autumn and winter, is tolerant of laboratory conditions and can survive for some time out of water. As no general d...

Heterogeneity in genetic composition among recruits of marine species is mostly due to a large variance in reproductive success mediated by oceanographic processes. Temporal genetic variation in a population of the European eel was quantified over 2 time scales among glass eel (1) interannual samples (cohorts), and (2) intra-annual samples within cohorts (‘arrival waves’). A total of 789 glass ...

A total of 2198 silver eels were Carlin-tagged and released at two sheltered and one exposed site in the western Baltic Sea. A total of 547 tagged silver eels were recaptured, corresponding to recoverv rates from 19 to 38% at the different sites. The majoritv of the recaptured silver cds was reporred from wirhin a radius of 20 km and within a period of less than 16 days after release. There was...