Inter- and intra-annual trends and status indicators of nektobenthic elasmobranchs off the Balearic Islands (northwestern Mediterranean)

摘要: We assessed the elasmobranch communities exploited by bottom trawl fishery off Balearic Islands (northwestern Mediterranean) analysing two time series containing information with different levels of detail: 1) a long-term abundance indices whole community landed from 1965 to 2009; and 2) shorter 2000 2009 data sources (daily sales records: 2000-2009; surveys: 2001-2009), that allowed shelf slope be analysed separately parameters studied. Temporal trends all these variables were used as ecological status indicators tested generalized additive models analysis variance. They finally summarised using Traffic Light methodology. The showed marked trends, an inter-annual decreasing trend would consequence large increase in fishing effort, intra-annual clear peak May accordance seasonal biological cycle species. However, last ten years revealed differences between slope, some increased significantly over on but did not follow any slope. methodology captured well, demonstrating its usefulness for interpreting transitions at glance.