Abstract
Anglerfish (Lophius piscatorius) collected from several locations in the southwestern European waters (from southwest of Ireland to northwest of Spain) were examined for the parasitic copepod Chondracanthus lophii in 2007, 2008 and 2009. The influence of host size, time (season, year) and spatial variables (geographical area, depth, latitude and longitude) on the infestation variability was studied. Zero-altered models (ZAMs) and generalized additive models (GAMs) were used to assess the prevalence and intensity of infection related to the variables studied. The variables which proved to have the greatest effects on the infestation were host size and geographical area, while the impact of variables such as year and season turned out to be less evident. Abundance, prevalence and intensity of C. lophii increased with host size. The highest infestation levels were recorded in the West of Ireland and on the Porcupine Bank, and within these areas the parasite load increased with latitude. Prevalence of C. lophii was lower in deep waters. These results suggest that the best conditions for the development of the C. lophii are found in the northernmost areas of the Atlantic Ocean and the host size is the major factor controlling the infestation levels.
Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark
Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark
Acknowledgements
We would like to acknowledge the assistance of the technical staff of the Instituto Español de Oceanografía (IEO) Centres of A Coruña and Santander and the scientific personnel involved in the research surveys. This study was supported by the European Union (Data Collection Regulation Framework) and the IEO. L. Cañás was initially funded by a grant from the Consellería de Educación e Ordenación Universitaria–Xunta de Galicia and subsequently by a research training grant from the IEO.
Notes
Published in collaboration with the University of Bergen and the Institute of Marine Research, Norway, and the Marine Biological Laboratory, University of Copenhagen, Denmark