Publications des scientifiques de l'IRD

Reed J., Shannon L., Velez L., Akoglu E., Bundy A., Coll Marta, Fu C., Fulton E. A., Gruss A., Halouani G., Heymans J. J., Houle J. E., John E., Le Loc'h François, Salihoglu B., Verley Philippe, Shin Yunne-Jai. (2017). Ecosystem indicators-accounting for variability in species' trophic levels. ICES Journal of Marine Science, 74 (1), p. 158-169. ISSN 1054-3139.

Titre du document
Ecosystem indicators-accounting for variability in species' trophic levels
Année de publication
2017
Type de document
Article référencé dans le Web of Science WOS:000397136400015
Auteurs
Reed J., Shannon L., Velez L., Akoglu E., Bundy A., Coll Marta, Fu C., Fulton E. A., Gruss A., Halouani G., Heymans J. J., Houle J. E., John E., Le Loc'h François, Salihoglu B., Verley Philippe, Shin Yunne-Jai
Source
ICES Journal of Marine Science, 2017, 74 (1), p. 158-169 ISSN 1054-3139
Trophic level (TL)-based indicators are commonly used to track the ecosystem effects of fishing as the selective removal of organisms from the food web may result in changes to the trophic structure of marine ecosystems. The use of a fixed TL per species in the calculation of TL-based indicators has been questioned, given that species' TLs vary with ontogeny, as well as over time and space. We conducted a model-based assessment of the performance of fixed TL-based indicators vs. variable TL-based indicators for tracking the effects of fishing pressure. This assessment considered three TL-based indicators (the trophic level of the landed catch (TLc), the marine trophic index (MTI) and the trophic level of the surveyed community (TLsc)), three fishing scenarios that targeted specific model groups (the low TL scenario (LTL), the high TL scenario (HTL) and a scenario encompassing broad-scale exploitation (ALL)) and ten contrasting marine ecosystems with four types of ecosystem modelling approaches that differ in their structure and assumptions. Results showed that, overall, variable TL-based indicators have a greater capacity for detecting the effects of fishing pressure than fixed TL-based indicators. Across TL-based indicators, TLsc displayed the most consistent response to fishing whether fixed or variable species' TLs were used, as well as the highest capacity for detecting fishing effects. This result supports previous studies that promote the use of survey-based indicators over catch-based indicators to explore the impacts of fishing on the structure of marine ecosystems. Across fishing scenarios, the low trophic level fishing scenario (LTL) resulted in the lowest consistency between fixed and variable TL-based indicator responses and the lowest capacity of TL-based indicators for detecting fishing effects. Overall, our results speak to the need for caution when interpreting TL-based indicator trends, and knowledge of the broader context, such as fishing strategies and exploitation history.
Plan de classement
Sciences fondamentales / Techniques d'analyse et de recherche [020] ; Ecologie, systèmes aquatiques [036] ; Ressources halieutiques [040]
Localisation
Fonds IRD [F B010069360]
Identifiant IRD
fdi:010069360
Contact