Environmental management of Atlantic cod (Gadus morhua) and turbot (Scophthalamus maximus): implications of noise, light and substrate

• Main Author: Sierra Flores, Rogelio
• Other Authors: Migaud, Herve, Davie, Andrew, CONACyT, Mexico
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: University of Stirling 2014
• Subjects: Light spectrum; Noise; turbot; Atlantic cod; larvae; juveniles; substrate; stress; Marine fisheries Management; Spectrum analysis; Aquaculture Environmental aspects; atlantic cod; Gadus morhua; Scophthalmus maximus; Turbot
• Online Access: http://hdl.handle.net/1893/20047; http://dspace.stir.ac.uk/bitstream/1893/20047/1/RogelioSierraFlores_PhD_Thesis_2014.pdf

During the last decades marine aquaculture has steadily expanded and diversified to include a wider range of commercial species. Despite the intense effort towards understanding the biological requirements of farmed species, several issues remain to be addressed. Mariculture success is restricted by a number of production bottlenecks including limited seed supply, caused mainly through a combination of compromised productivity in broodstock paired with high mortalities during the early life stages. Productivity and survival success is often dependent on the successful recreation of natural environmental conditions. While in a commercial setting a concerted effort is generally made to simulate key environmental stimuli there remains a lack of understanding of the significance of many potential signals. The overarching aim of this thesis was to investigate the effects of some of the overlooked environmental stimuli on fish performance in enclosed facilities and where possible relate this to the natural setting from which the species have been removed. The studies contained in this text are focused on the effects of anthropogenic noise, light spectral composition and substrate on the performance of broodstock and juvenile development of two valuable commercial marine species Atlantic cod (Gadus morhua) and turbot (Scophthalmus maximus). The aim of Chapter 3 was to test if artificial sound can act as a stressor in Atlantic cod and thereafter to examine if chronic sound disturbances can compromise broodstock spawning performance in land-based facilities. Results showed that anthropogenic noises in a land-based marine farm are within the auditory thresholds of cod and other fish species. Juvenile cod exposed to 10 min of artificial noise (100-1,000 Hz) from 10 to 20 dB 1 re µPa above background sound levels presented a typical acute stress response with a 4 fold elevation of plasma cortisol levels within 20 min, with a return to basal levels after 40 min, while the intensity of the stress response (in terms of ...