Charlotte Steeves

Student Speaker | Étudiant.e
Prolonged dietary exposure to marine chemical pollution has been cited as an underlying cause of reduced reproductive success and hormone disruption in birds. Seabirds occupy an apex position in the marine food web and are especially susceptible to high toxicant loads in ingested prey throughout their lifespan. Sub-lethal effects of toxicant exposure in seabirds are still relatively understudied and there is a pressing need to better predict changing patterns of accumulation and exposure. The General Seabird Toxicant Model, comprised of a bioenergetic and toxicokinetic sub-model, will integrate life history, environmental, empirical, and mechanistic data from a wide range of sources with the aim of predicting exposure, accumulation, and elimination of hydrophobic pollutants in seabirds. The bioenergetic sub-model estimates dietary exposure and storage of common pollutants with the aim of extrapolating to a wide variety of seabird species. The bioenergetics sub-model integrates life history traits and environmental data as predictors of percent body fat and daily energy requirements in adult seabirds across spatial and temporal variations. The toxicokinetic sub-model estimates chemical uptake, bioaccumulation in adipose tissues, and elimination routes of a selective group of common pollutants, including emergent and legacy pollutants. The model will be initially parameterized using data available in the literature for seabird bioenergetic components and growth, relevant environmental parameters, and chemical concentrations reported in various body tissues from both destructive and non-destructive sampling events.