Fig. 4.

Trends in a offshore abundances of cod (stock assessment estimates, ICES 2010a), sprat (acoustic estimates from the ordinary international acoustic survey, ICES 2010b) and stickleback (trawl hauls made during the ordinary international acoustic survey), and b coastal abundances of larger predators: cod, perch and pike together with local recruitment of perch and pike (in boxes: the number of young of the year fish YOY). a Sprat and stickleback data are from ICES subdivision 27, cod data are from subdivisions 25–32. Cod and sprat are estimated total numbers, while stickleback cpue is number per trawl hour. b Trap-net monitoring data (catch per night per trap) of cod, perch and pike between 1970 and 2002 from Gåsö (Mönsterås, county of Kalmar) on the southeast coast of Sweden. The Gåsö data is part of a larger time-series from four sites around a paper plant (Mönsterås bruk) which stops in 2003. Here, we present data exclusively from Gåsö, the site most affected by the open sea, because it is a good representation of fish both from the fresh-water and marine communities. Full pike data is presented in Sect. 1 in the electronic supplement to Ljunggren et al. (2010). Estimates of high, low and no recruitment of perch and pike are also based on Ljunggren et al. (2010)