Search

Rebuilding plans are required by law under the new Fish Stocks provisions of the revised Fisheries Act for major fish stocks prescribed under regulations that have declined to, or below, their limit reference point. The provisions state that the biology of the fish and environmental conditions facing the stock will be taken into consideration in the design of rebuilding strategies. Rebuilding strategies inform the development of rebuilding plans and should be regarded as integral to overall management (harvest) strategies. Science activities focus on the development and evaluation of management strategies in response to stated objectives, including rebuilding. Viewing a rebuilding strategy as separate from the overall management strategy can lead to the deferral of actions intended to prevent stock decline. Failure to plan rebuilding measures before they are needed can create hard-to-resolve conflicts with measures intended to provide opportunities for resource use. Increased likelihood that rebuilding is achieved depends on planning the transition from rebuilding to target outcomes within a management strategy. Like many other jurisdictions, Canada advocates management by reference points. Our review of international fisheries agreements highlights key elements that produced Canadian fisheries policy related to the Precautionary Approach. Interpretation of policy must distinguish between objectives that embed biological reference points related to abundance or fishing mortality, and the management measures intended to provide acceptable stock and fishery outcomes. As management by reference points can be challenging when there is data- or model-poverty, rebuilding strategies for such stocks should prioritize increasing information needed to adapt the rebuilding plan while preserving policy intent to avoid or correct undesirable stock states. We review obligations for recovery strategies under the Species at Risk Act and an ecocertification standard to evaluate where common information demands exist that could lead to efficiencies in providing advice. Existing Canadian rebuilding plans are reviewed to identify information needed to support rebuilding considerations in light of proposed regulations to support the Fish Stocks provisions. We discuss components of rebuilding strategies needed to meet proposed regulations. These include determining when rebuilding is needed, identifying the rebuilt state, and specifying a time period over which to implement a rebuilding plan. One science role is consistent communication of the plausible range of stock scenarios during the lifespan of the plan to inform expectations of decision-makers and resource users. Plan success can be enhanced by allowing for adaptation during the rebuilding period as new data, updated analyses, and revised objectives are considered. We suggest principles for developing national science guidelines for rebuilding fish stocks. Guidelines are intended to clarify expectations for, and to encourage, consistent science practices. We advocate a structured decision-making approach to developing feasible rebuilding strategies, identifying possible scenarios and eliciting objectives from resource users and decision-makers. The process can be used for data-poor contexts and maps directly into quantitative approaches such as management strategy evaluation. Finally, we provide a recommended list of elements for rebuilding strategies that should be reflected in science guidelines. [ABSTRACT FROM AUTHOR]

To assess the toxicity of winter-time atmospheric deposition in the oil sands mining area of Northern Alberta, embryo-larval fathead minnow (Pimephales promelas) were exposed to snowmelt samples. Snow was collected in 2011-2014 near (<7km) oil sands open pit mining operations in the Athabasca River watershed and at sites far from (>25km) oil sands mining. Snow was shipped frozen back to the laboratory, melted, and amended with essential ions prior to testing. Fertilized fathead minnow eggs were exposed (<24h post-fertilization to 7-16days post-hatch) to a range of 25%-100% snowmelt. Snow samples far from (25-277km away) surface mining operations and upgrading facilities did not affect larval fathead minnow survival at 100%. Snow samples from sites near surface mining and refining activities (<7km) showed reduced larval minnow survival. There was some variability in the potencies of snow year-to-year from 2011 to 2014, and there were increases in deformities in minnows exposed to snow from 1 site on the Steepbank River. Although exposure to snowmelt from sites near oil sands surface mining operations caused effects in larval fish, spring melt water from these same sites in late March-May of 2010, 2013 and 2014 showed no effects on larval survival when tested at 100%. Snow was analyzed for metals, total naphthenic acid concentrations, parent PAHs and alkylated PAHs. Naphthenic acid concentrations in snow were below those known to affect fish larvae. Concentrations of metals in ion-amended snow were below published water quality guideline concentrations. Compared to other sites, the snowmelt samples collected close to mining and upgrading activities had higher concentrations of PAHs and alkylated PAHs associated with airborne deposition of fugitive dusts from mining and coke piles, and in aerosols and particles from stack emissions., Capsule: Snow collected close to oil sands surface mining sites is toxic to larval fathead minnows in the lab; however spring melt water samples from the same sites do not reduce larval fish survival., (Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.)