2 Scope and objectives of the assessment

2.1 Objectives

The overarching objective of this project was to assess the cumulative effects of global change on the ecological communities of the Scotian Shelf Bioregion in eastern Canada. The specific objectives of this project were to:

1. provide a systematic characterization of the distribution and intensity of environmental drivers;
2. assess the spatial structure of biological communities;
3. evaluate the vulnerability of biological communities to multiple drivers, and;
4. conduct a spatial assessment of the cumulative effects of drivers on individual species and at the community level, using outputs from objectives 1 (distribution and intensity of drivers), 2 (spatial structure of biological communities), and 3 (food web vulnerability simulations due to multiple drivers).

2.2 Spatial and temporal scope

The cumulative effects assessment was conducted in the Scotian Shelf Bioregion, located off the eastern coast of Canada in the Atlantic Ocean [Figure 2.1; Fisheries and ceans Canada (2009) Fisheries and ceans Canada (2010)]. The study area includes the Bay of Fundy to the West, stops just before the Laurentian Channel to the East, and extends towards the continental shelf. The whole study area covers an area of 415 341 \(km^2\). For this assessment, we divided this area in a regular grid formed of cells of ~1 \(km^2\).

Figure 2.1: Limits of the study area for the cumulative effects assessment of global changes on the ecological communities of the Scotian Shelf Bioregion.

The temporal scope of the data was defined by the availability of data on environmental drivers on the Scotian Shelf Bioregion; we considered data from 2010 up to today and divided the assessment in two periods, i.e. from 2010 to 2015 (period 1) and from 2016 to 2021 (period 2). For drivers data for which temporal time series spanning this timeframe were unavailable (e.g. shipping), we used the same data for both periods (see section 6.2 and Table 6.6). Data on species occurrences were not divided by period and a single distribution was modeled for all species considered in the assessment (see section 6.1).

It is important to consider that the scope of the assessment fully constrains the interpretation of the results, i.e. the results must be interpreted with the spatiotemporal resolution, spatial extent, and the specific environmental drivers and species considered. No interpretation beyond this scope can be made; any interpretation that goes beyond these parameters is necessarily erroneous.