Table 1. The impact on the Living Planet Index (LPI) of halving or halting bottom trawling in six ocean systems, based on biomass trends in modelled vertebrate groups represented in the LPI.
Ocean system | LPI: Halve | LPI: Halt | Vertebrate biomass: halve | Vertebrate biomass: halt | Mammals | Seabirds | Sea turtles | Sharks & rays | Other fish |
Global | −2.5% | −1.3% | 0.7% | 2.0% | ∼ | ∼ | ∼ | ∼ | ∼ |
North Pacific | −5.6% | −0.7% | −0.1% | 1.4% | ∼ | ∼ | ∼ | ∼ | |
North & Baltic Seas | 2.7% | −3.3% | 2.2% | 5.1% | ∼ | ∼ | ∼ | ||
Mediterranean & Black Sea | −0.7% | −0.8% | 1.4% | 3.4% | ∼ | ||||
South Pacific | 3.6% | 5.3% | 3.8% | 7.5% | ∼ | ||||
South Atlantic | −4.7% | −3.8% | 0.1% | 0.3% | ∼ | ∼ | – | ∼ | |
Caribbean & Gulf of Mexico | −1.5% | −1.3% | 0.8% | 1.5% | – | – | ∼ | ∼ |
Columns show the % change in the LPI 30 years after implementation of the policies, and the % change in total vertebrate biomass; and for each taxonomic group, the general biomass trends for different species groups from the Ecopath models from halting bottom trawling (the general biomass trends per group were typically stronger under a halt in bottom trawling than under a halving of effort); symbols: – <5% change, >5% increase, >20% increase, >5% decrease, >20% decrease, ∼ mixed: different responses were seen across models, species and/or functional groups, blank denotes that the group was not modelled.