Robyn Forrest
BA, Curtin University, Perth
BSc (Hons 1, University Medal), University of Sydney
PhD, University of British Columbia 

Position
Robyn is currently a post-doctoral fellow at the Fisheries Centre, working with Dr Murdoch McAllister. She will use a Management Strategy Evaluation approach to evaluate alternative management options, including introduction of individual quotas, in US Gulf of Mexico grouper and snapper fisheries. She also maintains an active interest in using life history information to estimate sustainable harvest rates for data-limited species, particularly sharks.

Research
Robyn Forrest obtained her BSc in Biology and Marine Science at the University of Sydney. Her honours work, on factors affecting the distribution of intertidal benthic invertebrates, was supervised by Dr M.G. Chapman and Professor A.J. Underwood, at the Centre for Research on the Ecological Impacts of Coastal Cities, University of Sydney, New South Wales, Australia.

Her PhD, completed in December 2008, was supervised by Dr Tony Pitcher. Her thesis focused on estimation of productivity parameters for data-limited species and use of ecosystem models for evaluating trade-offs in multispecies fisheries. She is particularly interested in relationships between life history, selectivity (of fishing gear), density dependence in recruitment and the management parameter, optimal harvest rate. She explored these relationships in Australian deepwater dogsharks in the genus Centrophorus and has shown that optimal harvest rate is extremely low for these species. Importantly, this can be shown using only life history data and reasonable assumptions about gear selectivity (Forrest and Walters in press).  In February 2006, she spent a month visiting the Division of Marine and Atmospheric Research at Australia's Commonwealth Scientific and Industrial Research Organisation (Hobart), where she collaborated with Drs Beth Fulton and Marie Savina on a project to compare the predictions of structurally-different ecosystem models (Ecosim and Atlantis). The models were used to show that trade-offs between prevention of overfishing of low-productivity species (such as deepwater dogsharks) and achieving economic objectives can be severe. Work such as this can help clarify fisheries policy objectives, where conflicting management goals are often stated simultaneously (MS in prep).

Robyn has recently worked with Murdoch McAllister and others on a project for Fisheries and Oceans Canada using Bayesian hierarchical meta-analysis to estimate recruitment parameters and fisheries reference points for Pacific rockfishes (MS submitted to Canadian Journal of Fisheries and Aquatic Sciences).

Robyn was editor of the UBC Fisheries Centre Newsletters from 2003-2008. She has also worked as editor and author on numerous other projects, including the Fisheries section of the British Columbia Ministry of Environment's Coastal Environment Report 2006; and the user manual and help files for the newest version of ecosystem modelling software Ecopath with Ecosim 6.

PhD thesis "Simulation models for estimating productivity and trade-offs in the data-limited fisheries of New South Wales, Australia" (link to pdf)
Abstract: Recent shifts towards ecosystem based fisheries management (EBFM) around the world have necessitated consideration of effects of fishing on a larger range of species than previously. Non-selective multispecies fisheries are particularly problematic for EBFM, as they can contribute to erosion of ecosystem structure. The trade-off between catch of productive commercial species and abundance of low-productivity species is unavoidable in most multispecies fisheries. A first step in evaluation of this trade-off is estimation of productivity of different species but this is often hampered by poor data. This thesis developed techniques for estimating productivity for data-limited species, with the aim of clarifying EBFM policy objectives for the fisheries of New South Wales (NSW), Australia.

First, an age-structured model parameterised in terms of optimal harvest rate, U_MSY (Forrest et al. 2008) was developed. U_MSY is the maximum sustainable long term harvest rate that can be applied to a fish population, and is a measure of productivity that is comparable among species and easily communicated to managers. It also represents a valid threshold for prevention of overfishing. The model was used to derive U_MSY for 54 Atlantic fish stocks for which recruitment parameters had previously been estimated by other authors. In most cases, U_MSY was strongly limited by the age at which fish were first caught. However, for some species, U_MSY was more strongly constrained by life history attributes. For these species, increasing the age at which fish are first harvested would have little effect on U_MSY. These species, and the range of values of U_MSY that could be considered possible for these species, could be identified using only life history and selectivity information (i.e., without need for informative time series data). The model was applied to twelve species of Australian deepwater dogshark (Order Squaliformes), known to have been severely depleted by fishing on the NSW upper continental slope. Results showed the range of possible values of U_MSY for these sharks to be very low indeed (< 5% per year in some cases). These findings enabled a preliminary stock assessment for three dogsharks (Centrophorus spp.) currently being considered for threatened species listing in Australia. Preliminary results suggested they have been overfished and that overfishing continues.

Finally, an Ecopath with Ecosim ecosystem model, representing the 1976 NSW continental slope, was used to illustrate trade-offs in implementation of fishing policies under alternative policy objectives, including policies to protect dogsharks from overfishing and policies to maximise long-term economic value of the offshore trawl fishery in NSW. Results were compared with those of a biogeochemical ecosystem model (Atlantis) of the same system, built by scientists from CSIRO. While there were large differences in model predictions for individual species, they gave similar results when ranking alternative fishing policies, suggesting that ecosystem models may be useful for exploring broad-scale strategic management options.

Selected publications
Forrest, R.E. and C.J. Walters. 2009. Estimating thresholds to optimal harvest rate for long-lived, low-fecundity sharks accounting for selectivity and density dependence in recruitment. Canadian Journal of Fisheries & Aquatic Sciences 66: 2062-2080. PDF

Dulvy, N.K. and R.E. Forrest. 2010. Life histories, population dynamics and extinction risks in chondrichthyans. Chapter 17 In Sharks and their Relatives II. Biodiversity, Adaptive Physiology and Conservation. Edited by J. Carrier, J. Musick and M. Heithaus. CRC Press, Boca Raton. pp.639-679.

Brown, C.J., Fulton, E.A., Hobday, A.J., Matear, R., Possingham, H., Bulman, C., Christensen, V., Forrest, R.E., Gehrke, P.C., Gribble, N.A., Griffiths S.P., Lozano-Montes, H., Martin, J.M., Metcalf, S., Okey, T.A., Watson, R., Richardson, A.J. 2009. Effects of climate-driven primary production change on marine food webs: implications for fisheries and conservation. Global Change Biology 16(4):1194-1212.

Forrest, R.E., S.J.D. Martell, M.C. Melnychuk and C.J. Walters. 2008. An age-structured model with leading management parameters, incorporating age-specific selectivity and maturity. Canadian Journal of Fisheries and Aquatic Sciences 65: 286-296. PDF

Pitcher, T.J., R. Watson, R.E. Forrest, H. Valtýsson and S. Guénette. 2002. Estimating illegal and unreported catches from marine ecosystems: A basis for change. Fish and Fisheries 3: 317-339. PDF

Forrest, R.E., M.G. Chapman and A.J. Underwood. 2001. Quantification of radular marks as a method for estimating grazing of intertidal gastropods on rocky shores. Journal of Experimental Marine Biology and Ecology 258: 155-171. PDF

Scandol, J.P. and R.E. Forrest. 2001. Commercial catches as an indicator of stock status in NSW estuarine fisheries: trigger points, uncertainty and interpretation. In S.J. Newman, D.J. Gaughan, G. Jackson, M.C. Mackie, B. Molony, J. St. John and P. Kailola (eds.) Towards Sustainability of Data-Limited Multi-Sector Fisheries. Australian Society for Fish Biology Workshop Proceedings, Bunbury, Western Australia 23-24 September 2001. Fisheries Occasional Publications No. 6, May 2003, Department of Fisheries, Perth, Western Australia, 186 pp. PDF