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A series of paired-pond trials were completed during the winters of 2005 to 2008 to examine the effect of introducing artificial fish refuges on Great Cormorant Phalacrocorax carbo foraging behaviour, prey capture rates and fish losses in trial ponds, and to help refine their potential use as a tool in addressing cormorant-fisheries conflicts. Investigations comparing refuge volumes within a year provided clear evidence that larger refuges offered fish better protection than smaller ones. When compared across years, there was no clear relationship between refuge volume and prey consumption rate by Cormorants. There was, however, a very large difference in the consumption rate when ponds with no refuge were compared with any of the refuge volumes tested, suggesting that, in the absence of any other cover, the addition of even very small fish refuges can markedly reduce the quantity of fish eaten by Cormorants. Further trials indicated that introducing refuges as a single larger structure was more effective at reducing fish losses than an equivalent volume of refuge arranged as a number of smaller, widely-spaced, discrete units (>50% reduction in prey consumed per Cormorant visit). Trials further confirmed that the beneficial effects of fish refuges were not compromised by the presence of marginal habitat; indeed, prey consumption rates were >30% lower in the pond with additional simulated reed beds. The impact of refuge presence on fish loss rates varied between species, with Roach Rutilus rutilus benefitting in particular. The results are discussed in the wider context of interactions between Cormorants and their prey and with regard to the potential use of fish refuges as a management tool. [ABSTRACT FROM AUTHOR]

BACKGROUND The monk parakeet Myiopsitta monachus (Boddaert), native to South America, is an invasive species in several European countries, causing crop damage and potential negative impacts on wildlife. Only Spain and Great Britain have regulations to control monk parakeets, thus fast growth and spread of populations are likely to occur on a wide scale. The aims of this research are to update information on the distribution and population size of monk parakeets in Europe, assess whether differences in population growth or spread rate exist between populations, and provide recommendations to decision‐makers. RESULTS: Our study estimates that there are 23 758 monk parakeets in the wild, across 179 municipalities in eight European Union (EU) countries; 84% of these municipalities hold between 1 and 100 monk parakeets. All countries with a representative historical record are experiencing exponential growth of monk parakeets. Mediterranean countries are experiencing higher exponential growth, spread rate and faster colonization of new municipalities than Atlantic countries. CONCLUSIONS: We recommend that EU Mediterranean countries consider declaration of the monk parakeet as invasive alien species of regional concern, and develop coordinated efforts to monitor and manage the species, taking advantage of the low population sizes in most municipalities. © 2019 Society of Chemical Industry European populations of monk parakeet grow and spread differently according to the biogeographical region they occupy. We propose early action using a differentiated management suitable for these regions. [ABSTRACT FROM AUTHOR]

Capsule Daily food intake gave the best indication, with 7-23% of the pigeon population estimated to have been taken. Aims To assess the numbers of Scottish racing pigeons taken by Peregrines, based on the recovery of racing pigeon rings from Peregrine eyries and on the daily food intake (DFI) of Peregrines. Methods The estimate based on ring recoveries was derived from examination of the flight histories of birds whose rings had been recovered during searches at Peregrine eyries. The DFI-based approach involved deriving estimates of the biomass and number of Scottish racing pigeons taken based on the Peregrines' mean daily food requirements, and involved a comprehensive synthesis of available Peregrine dietary data. Results Estimates of the number of Scottish racing pigeons killed by Peregrines, during the 2002 racing season, were a minimum of 3083 from ring recoveries and between 25 283 and 78 385 based on DFI. This represented 1 % and 7-23% of the estimated total Scottish loft population respectively. The estimated Peregrine kills based on DFI represented 1 3-40% of total losses of Scottish racing pigeons to all causes; conversely 60-87% of total losses could not be attributed to Peregrines. Conclusions The recovery of racing pigeon rings from eyries provided only a minimum figure for the total losses of Scottish racing pigeons to Peregrines. Calculations based on Peregrine DFI, however, provided a good indication of the magnitude of Peregrine impact. The DFI technique is constrained by the lack of comprehensive data on relevant parameter values, leading to a broad range of estimates. Further research is encouraged to derive or refine parameter estimates for the DFI calculations in order to refine the estimates of potential kills from this approach. [ABSTRACT FROM AUTHOR]