Assessment of the impact of oil and gas industry emissions on the European Starling (Sturnus vulgaris)
Date
2004-04
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
ORCID
Type
Degree Level
Masters
Abstract
The size of the environmental footprint of the oil and gas industry in western
Canada is enormous, yet the potential impact of the industry and related chemical
emissions on local environments remains largely unknown. Therefore, when a study was
initiated to investigate the health, productivity, and immune competence of domestic
livestock chronically exposed to emissions from oil and gas batteries and associated field
facilities in the western provinces of Canada, a parallel study of a representative wildlife
species was conducted to gain further insight into the potential impact of the industry on
environmental health. To this end, wild European Starlings (Sturnus vulgaris) were
attracted to nesting locations surrounding oil and gas emission sites and suitable reference
sites through strategic placement of nest boxes in the breeding seasons of 2001 and 2002.
Spanning these two field seasons, reproductive performance (clutch size, egg weight and
volume, and hatchability), nestling condition and survival were examined in 120 nests
over a large geographical area in central Alberta. In addition, hepatic ethoxyresorufin-odeethylase
(EROD) activity (a measure of cytochrome P450IA1 biotransformation
activity) and concentrations of polycyclic aromatic hydrocarbon (PAH) metabolites in
bile were measured as biomarkers of exposure to certain contaminants, including PAHs,
present in oil and gas emissions. Hatchability and fledging success of the starlings were
not significantly associated with SO2, H2S, and benzene concentrations, and proximity to
oil and gas well sites. In contrast, ambient weather conditions, particularly total
precipitation and average temperature during the period of interest, were significantly
associated with these outcomes. Nestling size, when measured as tarsal length, was
significantly decreased with exposure to increasing benzene concentration. However this
effect was not seen on nestling development, measured using the length of the 10th
primary feather. None of nestling weight, egg weight or egg volume was associated with
any measurement of contaminant exposure. Although no association was found between
EROD activity or biliary PAH metabolite concentrations in starling nestlings and the
exposure variables measured, nest occupancy rate (an effect of nest location on the
outcome variable), and minimum temperature during the period from nest initiation to
fledging of the brood acted as predictors of EROD activity, while total precipitation was associated with PAH metabolite residues in nestlings in 2001. Studies such as this one of
wildlife populations may enhance our insight into potential toxicological mechanisms
associated with exposure to oil and gas industry emissions, and lead to the identification
of specific indicators of that could be applied in future research.
Description
Keywords
Citation
Degree
Master of Science (M.Sc.)
Department
Toxicology
Program
Toxicology