Oil exposure in a warmer Arctic: potential impacts on key zooplankton species
- 514 Downloads
Oil exploration activities are rapidly increasing in Arctic marine areas with potentially higher risks of oil spills to the environment. Water temperatures in Arctic marine areas are simultaneously increasing as a result of global warming. Potential effects of a combination of increased water temperature and exposure to the PAH pyrene were investigated on fecal pellet and, egg production and hatching success of two copepod species, Calanus finmarchicus and Calanus glacialis, sampled in Disko Bay, Greenland on 23–25 April 2008. The two species were exposed daily to nominal pyrene concentrations of 0-0.01-0.1-1-10-100 nM at water temperatures of 0.5, 5 and 8°C for 9 and 7 days, respectively. Daily measurements of faecal pellet production, egg production and hatching showed different responses of the two species to the applied stressors. When temperature increased, low concentrations of pyrene caused a decrease in faecal pellet production by C. finmarchicus, whereas C. glacialis faecal pellet production showed no negative response to pyrene exposure when temperatures increased. Pyrene exposure decreased egg production of C. finmarchicus at all temperatures, but the species was more sensitive at 0.5 and 8°C. A lag period of 1 day before egg production began was prolonged with several days when warmer water was combined with pyrene exposure. Egg production by C. glacialis was only negatively affected by pyrene in a dose-dependent manner at 0.5°C. Hatching success in both species was not affected by pyrene, where increased water temperatures led to a higher hatching success. In conclusion, C. glacialis seemed to be the less sensitive of the two species to the stress combination of increased water temperature and pyrene exposure. As a consequence of the differential responses of the two species, their competition can be impaired with a consequent impact on energy transfer between trophic levels.
KeywordsPAHs Pyrene Faecal Pellet Spring Bloom Hatching Success
This study was financed by the National Environmental Research Institute (NERI), Carlsberg Foundation, ECOGREEN and the Danish Natural Sciences Research Council. We would like to thank Arctic station in Qeqertarsuaq and the scientific leader Outi Tervo, University of Copenhagen, who provided us with excellent laboratory facilities and logistical support. At sea, RV Porsild and crew provided a great working platform.
- ACIA (Arctic Climate Impact Assessment) (2005) Arctic climate impact assessment. Cambridge University Press, CambridgeGoogle Scholar
- AMAP (2007) Arctic oil and gas 2007. Arctic monitoring and assessment programme, Oslo. xiii + 40 pGoogle Scholar
- Bignert A, Cossa D, Emmerson R, Fryer R and others (2004) OSPAR/ICES workshop on the evaluation and update of background reference concentrations (B/RCs) and ecotoxicological assessment criteria (EACs) and how these assessment tools should be used in assessing contaminants in water, sediment, and biota. Workshop, The Hague, 9–13 February 2004. Final Report. OSPAR CommissionGoogle Scholar
- Buchmann MF (1999) NOAA screening quick reference tables, NOAA HAZMAT report 99–1, Coastal Protection and Restoration Division, National Oceanic and Atmospheric Administration, Seattle, WAGoogle Scholar
- Falk-Petersen S, Timofeev S, Pavlov V, Sargent JR (2006) Climate variability and the effect on arctic food chains. The role of Calanus. In: Orbaek JB et al (eds) Arctic-alpine ecosystems and people in a changing environment. Springer Verlag, BerlinGoogle Scholar
- Swalethorp R, Kjellerup S, Dünweber M, Nielsen TG, Møller EF, Rysgaard S, Hansen BW (2011) Grazing, production and biochemical evidence of differences in the life strategies of Calanus finmarchicus, C. glacialis and C. hyperboreus in Disko Bay, Western Greenland. Mar Ecol Prog Ser (in press)Google Scholar