Using indicators for evaluating, comparing, and communicating the ecological status of exploited marine ecosystems. 2. Setting the scene

Abstract

Shin, Y-J., Shannon, L. J., Bundy, A., Coll, M., Aydin, K., Bez, N., Blanchard, J. L., Borges, M. F., Diallo, I., Diaz, E., Heymans, J. J., Hill, L., Johannesen, E., Jouffre, D., Kifani, S., Labrosse, P., Link, J. S., Mackinson, S., Masski, H., Möllmann, C., Neira, S., Ojaveer, H., ould Mohammed Abdallahi, K., Perry, I., Thiao, D., Yemane, D., and Cury, P. M. 2010. Using indicators for evaluating, comparing, and communicating the ecological status of exploited marine ecosystems. 2. Setting the scene. – ICES Journal of Marine Science, 67: 692–716. Background is provided to the selection of ecological indicators by the IndiSeas Working Group, and the methodology adopted for analysis and comparison of indicators across exploited marine ecosystems is documented. The selected indicators are presented, how they are calculated is explained, and the philosophy behind the comparative approach is given. The combination of selected indicators is intended to reflect different dynamics, tracking processes that display differential responses to fishing, and is meant to provide a complementary means of assessing marine ecosystem trends and states. IndiSeas relied on inputs and insights provided by the local experts from participating ecosystems, helping to understand state and trend indicators and to disentangle the effect of other potential ecosystem drivers, such as climate variability. This project showed that the use of simple and available indicators under an ecosystem approach can achieve a real, wide-reaching evaluation of marine ecosystem status caused by fishing. This is important because the socio-economics of areas where fishing activities develop differs significantly around the globe, and in many countries, insufficient data are available for complex and exhaustive analyses.

Size-selective fishing drives species composition in the Celtic Sea

“…Blanchard et al (2010) showed how time-series of community-level indicators, including SBIs, reveal strong effects of selective fishing, but no study has so far measured the relative importance of individual-level effects compared with species-level effects. Here, we contrast the effects of size-selective fishing as seen through the large fish indicator (LFI; Cury and Christensen, 2005;Greenstreet et al, 2011) with the effects seen through the large species indicator (LSI; Shin et al, 2010).…”

“…The LFI is sensitive to both changes in intraspecific size structure and changes in the abundance of species of different size. To isolate the latter effect, the analogous LSI was considered by Shin et al (2010), although it was discarded in favour of the proportion of predatory fish, to avoid setting a species size-threshold (Shin et al, 2010). The LSI is defined as the biomass proportion of large species in a community (as sampled by a specific survey protocol), where size is measured in terms of maximum length L max , and species are classified as large or small according to a chosen threshold value g, which can be chosen in relation to h or independently.…”

Global in scope and regionally rich: an IndiSeas workshop helps shape the future of marine ecosystem indicators

“…This list complements the IndiSeas I ecological indicators (Shin et al 2010a) which we continue to estimate: mean length of fish in the community; TL of landings; proportion of under-and moderately exploited stocks; proportion of predatory fish biomass; mean lifespan; 1/CV of the total biomass surveyed; and 1/(landings/biomass).…”

“…The first phase of IndiSeas (IndiSeas I: 2005(IndiSeas I: -2009) culminated in the publication of nine papers Shin et al 2010a) and a website of comparative analyses (http://www.indiseas.org). Nearly 80% of the 19 ecosystems assessed using a suite of 8 ecological indicators were classified as deteriorating over the past several decades (Bundy et al 2010).…”

Critical assessment of the current understanding/ knowledge of the framework of the Ecosystem Approach to Fisheries in the Mediterranean and Black Seas

“…the GADGET model, Taylor and Stefánsson 2004) or models of intermediate complexity for ecosystem assessments (MICE) (Plagányi et al 2012), as a reasonable compromise for the application of ecosystem models in the EAF. However, the EAF can also be implemented through the relatively modelfree indicator approach (Cury et al 2005, Didier et al 2010, Shin et al 2010.…”