Effects of pyrene exposure and temperature on early development of two co-existing Arctic copepods

Abstract

Oil exploration is expected to increase in the near future in Western Greenland. At present, effects of exposure to oil compounds on early life-stages of the ecologically important Calanus spp. are unknown. We investigated the effects of the oil compound pyrene, on egg hatching and naupliar development of the calanoid copepods Calanus glacialis and C. finmarchicus, two key species in the Disko Bay, Western Greenland. At low temperature the nauplii of C. glacialis experienced reduced growth when exposed to pyrene, and survival in both species decreased. Naupliar mortality increased with temperature at high pyrene concentration in C. finmarchicus. Both Calanus species were affected by pyrene exposure but C. finmarchicus was more sensitive compared to C. glacialis. Lowered growth rate and increased mortality of the naupliar stages entail reduced recruitment to copepod populations. Exposure to pyrene from an oil spill may reduce the standing stock of Calanus, which can lead to less energy available to higher trophic levels in the Arctic marine food web.

Early development of Calanus hyperboreus nauplii: Response to a changing ocean

“…Mortality during the experiment was high; 77% of the fed and 66% of the starved nauplii died during the incubation period of 40 d. However, this is comparable to mortality of C. glacialis nauplii measured over 42 d, during which 78% and 95% of the nauplii died in fed and starved treatments, respectively (Daase et al 2011). As argued in Daase et al (2011) the reason for high mortality is the long duration of incubation, whereas daily mortality rates (0.09 and 0.04 d 21 for fed and starved nauplii, respectively) are similar to the rates found for other Calanus species (Daase et al 2011;Grenvald et al 2012). The lower mortality of starved C. hyperboreus in the present study probably reflects the high lipid content of the nauplii, which enables them to endure starvation and obtain a higher survival rate than C. glacialis.…”

Ecotoxicological investigation of the effect of accumulation of PAH and possible impact of dispersant in resting high arctic copepod Calanus hyperboreus

“…This generally results in a large day-to-day variance between individual bottles (females) making significant results hard to obtain. Adverse effects of PAH exposure have been reported in previous studies, although the effects there were, at best, minor (Nørregaard et al, 2014;Jensen et al, 2008;Hjorth and Nielsen, 2011;Grenvald et al, 2012). In contrast, positive effects of PAH exposure on the egg production of C. glacialis has been reported (Hjort and .…”

“…There is also an indication, i.e., minor or no significant differences, that exposure to oil compounds can affect hatching of Calanus spp. nauplii (Jensen et al, 2008;Hjorth and Nielsen, 2011;Grenvald et al, 2012;Nørregaard et al, 2014). A high accumulation rate increases the risk of toxic effects on the copepods and offspring as well as the risk for exposure of fish, bird and marine mammals that feed on the copepods.…”

Assessing the Impact of Oil Spills on Marine Organisms

“…H. sarsi feeds mainly on Pontoporeia affinis whose biomass also decreased significantly and hence it was assumed that the reduced population of H. sarsi may be associated with decreased food source [73]. Current research has established that polychaetes are resistant to oil and hence can be used for purification and sanitation of contaminated water and shorelines [74].…”