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A sample of 166 conger eel, Conger conger (Linnaeus, 1758) were captured between August 1998 and June 1999, from the inshore south coastal waters of Ireland using demersal trawl, longlines, lobster and shrimp pots. The range in length was 33–159 cm and weight was 0.05–12.0 kg. Age, determined from vertebrae and sagittal otoliths, ranged from 4 to 20 years. Vertebrae were found to be the most effective tool for ageing. A linear relationship was found between total length and otolith radius. A curvilinear model best described the relationship between total length and vertebral radius. Both otoliths and vertebrae were used in the back-calculation technique and the von Bertalanffy growth function was fitted. Population growth curves were constructed from both vertebral and otolith measurements. Growth parameters, L∞ and k were estimated for individual fish showing large ranges in values. L∞ from otoliths ranged from 170 to 320 m, and k from 0.01 to 0.09. From vertebrae, L∞ ranged from 130 to 390 m and k from 0.01 to 0.13. Population estimates from otoliths gave results of L∞=271 cm, k=0.037, t0=−1.396 and from vertebrae gave results of L∞=214 cm, k=0.059, t0=−1.960. Condition factor ranged from 0.03 to 1.73 and gonadosomatic index from 0.53 to 7.05. The greatest increase in condition occurred between summer and autumn, while the greatest increase in gonadosomatic index occurred between autumn and winter. It was not possible to determine the sex of the eels from gross gonad appearance. Histological analysis of the gonads revealed that all conger eels were female. The absence of males and of ripe or spent females in the inshore south coastal inshore waters suggests that conger eels leave this region to spawn. This study has provided the first published data on age, growth and gonad development of a population of the species in the Northeast Atlantic. [Copyright &y& Elsevier]

Characterizing patterns of animal movement is a major aim in population ecology, and yet doing so at an appropriate spatial scale remains a major challenge. Estimating the frequency and distances of movements is of particular importance when species are implicated in the transmission of zoonotic diseases. European badgers (Meles meles) are classically viewed as exhibiting limited dispersal, and yet their movements bring them into conflict with farmers due to their potential to spread bovine tuberculosis in parts of their range. Considerable uncertainty surrounds the movement potential of badgers, and this may be related to the spatial scale of previous empirical studies. We conducted a large-scale mark-recapture study (755 km(2); 2008-2012; 1935 capture events; 963 badgers) to investigate movement patterns in badgers, and undertook a comparative meta-analysis using published data from 15 European populations. The dispersal movement (>1 km) kernel followed an inverse power-law function, with a substantial 'tail' indicating the occurrence of rare long-distance dispersal attempts during the study period. The mean recorded distance from this distribution was 2.6 km, the 95 percentile was 7.3 km and the longest recorded was 22.1 km. Dispersal frequency distributions were significantly different between genders; males dispersed more frequently than females, but females made proportionally more long-distance dispersal attempts than males. We used a subsampling approach to demonstrate that the appropriate minimum spatial scale to characterize badger movements in our study population was 80 km(2), substantially larger than many previous badger studies. Furthermore, the meta-analysis indicated a significant association between maximum movement distance and study area size, while controlling for population density. Maximum long-distance movements were often only recorded by chance beyond the boundaries of study areas. These findings suggest that the tail of the badger movement distribution is currently underestimated. The implications of this for understanding the spatial ecology of badger populations and for the design of disease intervention strategies are potentially significant., (© 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.)