Tim Barrett

Ph.D. Candidate (January 2009 – present)

Tim BarrettHometown: Quispamsis, N.B.
Education: B.Sc. in Mathematics, University of New Brunswick, 2008
Contact: tim.barrett@unb.ca, 506-648-5985

Current Research: "Influence of reproductive strategy and mobility of fish on study designs for environmental monitoring programs using fish as sentinels"

Federally regulated environmental effects monitoring (EEM) programs have been implemented for pulp and paper and metal mining effluents in Canada. With the recent development of large pulp mills in Chile, Brazil, and Uruguay, there has been increased attention on developing EEM programs is these areas.

Unlike the EEM program in Sweden, which regulates species selection and timing of sampling, there have been no such restrictions in Canada, resulting in the use of more than 65 species for EEM programs.

The objective of this research is to study the reproductive biology and mobility of fish species to improve EEM study designs, by identifying effective sentinel species and optimal sampling times. The reproductive strategies of abundant species in New Brunswick will be determined using histological analyses of ovaries and a method to predict the reproductive biology of fish species using pre-spawning ovary weight: body weight relationships will be tested.

Optimal sampling times to detect reproductive impacts for species used in Canada’s EEM program will be determined based on reproductive strategies and seasonal changes in gonad sizes. In South America, basic life history characteristics for many species are unknown, but are necessary to consider when designing an effective EEM study. In Uruguay, basic life history information of several abundant fish species will be collected to develop an EEM program for a pulp mill on the Rio Uruguay.

Seasonal changes in gonad size and histological analyses of ovaries will reveal spawning times and will be used to identify optimal sampling times. Mobility will be assessed by estimating the scale of feeding movements through changes in δ13 C signatures from fish and benthic invertebrates collected along a gradient as the base of the food web shifts from allochthonous to autochthonous origin.

Recent scientific publications

Rossong, MA, PA Quijón, PVR Snelgrove, TJ Barrett, CH McKenzie, and A Locke, In Press. Regional differences in foraging behaviour of invasive green crab (Carcinus maenas) populations in Atlantic Canada. Biological Invasions.

Barrett TJ. 2011. Computations using analysis of covariance. Wiley Interdisciplinary Reviews: Computational Statistics 3: 260-268.

Barrett TJ and KR Munkittrick 2010. Seasonal reproductive patterns and recommended sampling times for sentinel fish species used in environmental effects monitoring programs in Canada. Environmental Reviews 18: 115-135.

Barrett TJ, RB Lowell, MA Tingley, and KR Munkittrick. 2010. Effects of pulp and paper mill effluent on fish: a temporal assessment of fish health across sampling cycles. Environmental Toxicology and Chemistry 29: 440-452.

Barrett TJ, MA Tingley, KR Munkittrick, and RB Lowell. 2010. Dealing with heterogeneous regression slopes in analysis of covariance: new methodology applied to environmental effects monitoring fish survey data. Environmental Monitoring and Assessment 166: 279-291.

Munkittrick KR, TJ Barrett, and ME McMaster. 2010. Guidance for site-specifically assessing the health of fish populations with emphasis on Canada’s environmental effects monitoring program. Water Quality Research Journal of Canada 45: 209-221.