Terms of Reference

Workshop on Shellfish Monitoring Network in the Gulf Region

Regional Workshop - Gulf Region

Moncton, (NB)
February 1, 2011

Chairperson: G. Chaput (DFO Gulf Region)

Context

In the fall of 2003, DFO and the New Brunswick Department of Agriculture, Fisheries and Aquaculture (NBDAFA) began a planning exercise to streamline the site review process for oyster aquaculture and the result was the development of the Bay Management Framework (BMF). Water column oyster aquaculture projects in N.B. have similar structural characteristics, similar planning and permitting process requirements and were considered to have predictable and mitigatable ranges of potential environmental effects. For this reason and as part of the BMF, a replacement class screening report (RSCR) was agreed for "water column oyster aquaculture in New Brunswick" (Transport Canada, TC 2006). A preliminary qualitative risk assessment carried out by DFO confirmed that the anticipated scale of negative effect with off-bottom oyster culture was low (as stated in TC 2006). In the pathways analysis, within the biophysical environment, the carrying capacity component was considered and no significant pathway of effects remained if two practices were implemented (TC 2006, p. 32, Table 2):

• Limitation of total surface area of bays, reserved for shellfish aquaculture, and
• Long term monitoring program of mollusc productivity.

As a result, DFO and NBDAFA opted to allocate marine space for shellfish aquaculture conservatively (10% of surface area of a bay in aquaculture production) and both departments indicated that they would invest in long term monitoring of mollusc productivity in natural shellfish population and oyster aquaculture areas.

Cranford et al. (2006) concluded that shellfish performance indicators could provide an indication as to whether shellfish aquaculture is affecting the system to a greater extent than can be absorbed by natural processes. The caged bivalve approach was proposed to monitor lease-scale effects but the interpretation of the results would require complementary information on a wide range of variables that can affect bivalve growth (temperature, currents, food abundance and nutritional quality, salinity, etc.).

The standardized Shellfish Monitoring Network (SMN) in the southern Gulf of St. Lawrence was proposed to track growing conditions within major cultivation bays with the objective to better understand the naturally-occurring variability (both spatial and temporal) in shellfish growing conditions. An understanding and accounting for such variability was considered important in order to gauge the effectiveness of bay management decisions. The SMN protocol consists of deploying juvenile blue mussels (Mytilus edulis) and american oysters (Crassostrea virginica) at fixed stations across the southern Gulf in the spring and thereafter to monitor their growth and meat content until the onset of winter. The SMN in the southern Gulf began in 1996 and has continued, although with some modifications, into 2009.

The RCSR for water column culture of oysters in New Brunswick is to be reviewed and updated for September 2012. The questions from DFO Habitat Management (HM) are:

• Is the information from the Shellfish Monitoring Network a sufficient index of effects on productivity to signal when the environmental effects associated with the aquaculture activities exceed the assessment of the RCSR?
• Is the presently established threshold of 10% of surface area of a bay in aquaculture production for N.B. sufficient to ensure that there is negligible impact on fish habitat? The component of the habitat of interest is the carrying capacity.

As there are no RCSR for aquaculture bivalve activities in the other provinces of the southern Gulf, for non-water-column oyster culture, nor for the other bivalve species being cultured (blue mussel), the advice from these analyses could assist in the decisions being taken to manage these activities.

Objectives

There has not been any peer review of the entire SMN data for the 1996 to 2009 period. To address the questions from DFO HM, an initial science review of the SMN data and analyses will be conducted to determine if the information is appropriate for the intended use, as described in the RCSR. The information from the SMN will be reviewed in a workshop and will consider the following:

1. Description of the SMN design, and the data (biological data, other data such as temperature, salinity, etc) collected, by location and year.
2. To the extent possible, an analysis of the variance within sites, among sites, and among years, among bivalve species, of growth rates of bivalves in the SMN experiment and exploration of potential factors that can account for the variance.
3. If the information on bay-specific bivalve aquaculture production can be collected at a suitable scale, correlation analyses of variations in growth rates and the intensity of bivalve aquaculture production in the monitored bays will be explored.
4. Conclusion on whether there is sufficient information in the SMN initiative to proceed with a formal advisory process to address the questions from DFO HM on thresholds for intensity of bivalve production within bays.
1. If the workshop concludes that there is sufficient information to proceed with the science peer review for providing advice, a workplan leading to that review will be developed (additionnal data requirements, analyses to be conducted, date of the review).
2. If the workshop concludes that the information in the SMN is insufficient to address the questions from management, recommendations on monitoring and research requirements to address the questions will be developed.

Expected Publications

A proceedings report will be produced that summarizes the points of discussions and recommendations based on the conclusions of whether or not there is sufficient information in the SMN data to address the science advice request from DFO HM. A research document may be produced in support of the proceedings. The proceedings document is expected within two months of the date of the meeting. When finalized, the products from the meeting will be posted on the DFO Canadian Science Advisory Secretariat website.

Participation

Discussions at the workshop will be technical in nature and the review will require participants familiar with a broad range of techniques associated with data collection, experimental design, and statistical analyses. No management advice will be provided. Participation will be by invitation and participants from the following are expected:

• DFO Oceans and Science
• Invited external experts

References

Cranford, P.J., R. Anderson, P. Archambault, T. Balch, S.S. Bates, G. Bugden, M.D. Callier, C. Carver, L. Comeau, B. Hargrave, W.G. Harrison, E. Horne, P.E. Kepkay, W.K.W. Li, A. Mallet, M. Ouellette, P. Strain. 2006. Indicators and Thresholds for Use in Assessing Shellfish Aquaculture Impacts on Fish Habitat. DFO Can. Sci. Advis. Sec. Res. Doc. 2006/034.

DFO. 2006. Assessing Habitat Risks Associated with Bivalve Aquaculture in the Marine Environment. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2006/005.

DFO. 2010. Pathways of Effects for Finfish and Shellfish Aquaculture. DFO Can. Sci. Advis. Sec. Sci. Advis. Rep. 2009/071.

Fisheries and Oceans Canada. 2003. A scientific review of the potential environmental effects of aquaculture in aquatic ecosystems. Volume I. Far-field environmental effects of marine finfish aquaculture (B.T. Hargrave); Ecosystem level effects of marine bivalve aquaculture (P. Cranford, M. Dowd, J. Grant, B. Hargrave and S. McGladdery); Chemical use in marine finfish aquaculture in Canada: a review of current practices and possible environmental effects (L.E. Burridge). Can. Tech. Rep. Fish. Aquat. Sci. 2450: ix + 131 p.

McKindsey, C.W., M.R. Anderson, P. Barnes, S. Courtenay, T. Landry, M. Skinner. 2006. Effects of Shellfish Aquaculture on Fish Habitat. DFO Can. Sci. Advis. Sec. Res. Doc. 2006/011.

Transport Canada. 2006. Replacement Class Screening for Water Column Aquaculture in New Brunswick. Report of the Environmental Assessment Agency. Moncton, N.B. 75 p. (draft version of April 25, 2006).