This study assesses the impacts of climate change on national fisheries and quantifies national-scale benefits of implementing climate-adaptive fisher

Realistic fisheries management reforms could mitigate the impacts of climate change in most countries

The following is an excerpt from an article published by the Global Aquaculture Advocate: 

Forecasting global fisheries biomass, catch and profits to 2100 under three climate scenarios and five levels of management reforms

Marine fisheries provide a vital source of food for over half the world’s population and support the livelihoods of more than 56 million people globally. However, the ability for marine fisheries to provide these services is threatened by climate change, compromising the contribution of the oceans to sustainable development goals. Ocean warming has already reduced the productivity of many fisheries around the globe, with some regions having experienced up to 35 percent declines in maximum sustainable yield.

An ensemble of marine ecosystem models forecasts by Lotze and co-workers continued showing decreases in marine animal biomass of 4.8 to 17.2 percent by 2100 under low- to high-end emissions scenarios, respectively. In general, productivity is predicted to decrease in tropical and temperate regions and increase towards the poles, as marine organisms shift distributions to maintain their thermal niches. These regional shifts in productivity, range, and fishing opportunity will result in regional discrepancies in food and profits from fisheries. Under current policies, these effects will be unevenly distributed with tropical developing countries and small island developing states exhibiting the greatest vulnerability to the impacts of climate change on fisheries.

Realistic fisheries management reforms could mitigate the impacts of climate change in most countries (Image:  Christopher M. Free Tracey Mangin ... Steven D. Gaines )

Gaines and co-workers provided a critical step towards understanding the opportunities for fisheries reforms to mitigate the impacts of climate change at a global-level. They showed, at a global scale, that business-as-usual fisheries management would exacerbate the negative impacts of climate change, but that climate-adaptive fisheries reforms would maintain global fisheries health, harvest, and profits into the future under all but the most severe emissions scenario evaluated.

However, the effectiveness and feasibility of these reforms is likely to vary regionally, with higher capacity, poleward countries gaining productivity and lower capacity, tropical countries losing productivity. A critical next step then in understanding the potential for fisheries reform to mitigate the impacts of climate change on human livelihoods is to examine the performance of more realistic productivity adaptations at the country level.

Click image to enlarge

This article – adapted and summarized from the original publication (Free, C.M. et al. 2020.) – reports on a study based on the Gaines, et al., model that evaluated the impacts of climate change and management reform on global fisheries and forecast the impacts of climate change on national fisheries; quantified the national-scale benefits of implementing climate-adaptive fisheries reforms; and presented an overview of promising methods for achieving the benefits of climate-adaptive fisheries reform along a gradient of scientific, management, and enforcement capacities.

Study setup

We used the climate-linked fisheries bioeconomic model by Gaines and co-workers mentioned before to examine country-level changes in fisheries status, catches and profits under three emissions scenarios (RCPs 4.5, 6.0 and 8.5) and five management scenarios from 2012 to 2100.

Click image to enlarge

Projections were made through 2100 using the following general procedure: (1) distributions were updated based on a modified version of the species distribution model by García Molinos and co-workers; (2) carrying capacities were assumed to change in proportion to changes in range size, i.e., a 10 percent increase in range size results in a 10 percent increase in carrying capacity; and (3) biomass, catch and profits were then updated based on a modified version of the Costello, et al., the bioeconomic model by Costello and co-workers and the selected management scenario.

For detailed information on the study design; species distribution model; bioeconomic model and management scenarios; country-level fisheries outcomes; and the guiding principles for climate-adaptive fisheries management, refer to the original publication. (continues...)

Author: Christopher M. Free, Ph.D. Tracey Mangin, M.S. Jorge García Molinos, Ph.D. Elena Ojea, Ph.D. Merrick Burden, M.Sc. Christopher Costello, Ph.D. and Steven D. Gaines, Ph.D / Global Aquaculture Advocate | Read the full article by clicking de link here

[email protected]
www.seafood.media

Address:	85 New Hampshire Ave., Ste. 200
City:	Portsmouth
State/ZIP:	New Hampshire (NH 03801)
Country:	United States
E-Mail:	[email protected]
More about:

Print