Global estimation of areas with suitable environmental conditions for mariculture species - PubMed (original) (raw)

Global estimation of areas with suitable environmental conditions for mariculture species

Muhammed A Oyinlola et al. PLoS One. 2018.

Abstract

Aquaculture has grown rapidly over the last three decades expanding at an average annual growth rate of 5.8% (2005-2014), down from 8.8% achieved between 1980 and 2010. The sector now produces 44% of total food fish production. Increasing demand and consumption from a growing global population are driving further expansion of both inland and marine aquaculture (i.e., mariculture, including marine species farmed on land). However, the growth of mariculture is dependent on the availability of suitable farming areas for new facilities, particularly for open farming practices that rely on the natural oceanic environmental parameters such as temperature, oxygen, chlorophyll etc. In this study, we estimated the marine areas within the exclusive economic zones of all countries that were suitable for potential open ocean mariculture activities. To this end, we quantify the environmental niche and inferred the global habitat suitability index (HSI) of the 102 most farmed marine species using four species distribution models. The average weighted HSI across the four models suggests that 72,000,000 km2 of ocean are to be environmentally suitable to farm one or more species. About 92% of the predicted area (66,000,000 km2) is environmentally suitable for farming finfish, 43% (31,000,000 km2) for molluscs and 54% (39,000,000 km2) for crustaceans. These predictions do not consider technological feasibility that can limit crustaceans farming in open waters. Suitable mariculture areas along the Atlantic coast of South America and West Africa appear to be most under-utilized for farming. Our results suggest that factors other than environmental considerations such as the lack of socio-economic and technological capacity, as well as aqua feed supply are currently limiting the potential for mariculture expansion in many areas.

PubMed Disclaimer

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Fig 1. Global trends in food fish production from 1950 to 2010 with production from capture fisheries, freshwater aquaculture and mariculture.

Data from Sea Around Us (2010) and FAO (2012).

Fig 2. Prediction evaluation of each SDM used in the analysis.

(A) AUC for the habitat suitability index (HSI) for natural occurrences of farmed species across SDM; (B) AUC for mariculture location HSI across SDMs. The horizontal lines represent median values. The upper and lower boundaries of the box represent the upper and lower quartiles of the data. ENFA- Ecological Niche Factor Analysis, MAXENT- Maximum Entropy, NPPEN- Non- Parametric Probabilistic Ecological Niche and SRE- Surface Range Envelope.

Fig 3. The relationship between predicted mariculture habitat suitability index (HSI) and natural occurrence habitat suitability index.

(A) Regression of global predicted mariculture HSI and natural occurrence HSI (p<0.001). (B) Histogram of adjusted R2 of individual species’ regression analysis with a mean value of 0.66.

Fig 4. Predicted suitable marine area for mariculture and the agreement among SDMs.

Blue—high agreement (4 models), Yellow—moderate agreement (3 models), Green—low agreement (2 models) and Red–very low agreement (1 model).

Fig 5. Potential marine area suitable for mariculture production and current versus potential farmed species richness.

(A) Total predicted suitable marine areas for mariculture in blue and unsuitable marine areas in red based on an average of four different species distribution models; (B) Comparison between present numbers of species farmed in different countries with potential numbers of farmed species based on model outputs.

Fig 6. Predicted marine area suitable for mariculture from four species distribution models: ENFA, MAXENT, NPPEN and SRE; and weighted Multi-model.

ENFA predicted the highest area with 107 million km2 while the Multi-model predicted 72 million km2.

Fig 7

Global predicted potential mariculture area and regional farmed species richness for (A) finfish (66 million km2); (A) crustaceans (39 million km2); and (C) molluscs (31 million km2).

Fig 8. Total predicted potential mariculture area for 20 of the most cultured species based on cumulative production from 1950–2010.

(A) Classification by total potential marine areas suitable for farming. (B) Classification by total present and potential number of countries.

References

1. Golden C, Allison Edward H., Cheung WWL, Dey Madan M., Halpern Benjamin S., McCauley Douglas J., et al. Fall in fish catch threatens human health. Natural. 2016;534(7607):317–20. -PubMed
1. Roos N, Wahab MAC, Thilsted SH. The role of fish in food-based strategies to combat vitamin A and mineral deficiencies in developing countries. The journal of Nutrition. 2007;137(4):1106–9. -PubMed
1. Tacon AGJ, Metian M. Fish Matters: Importance of Aquatic Foods in Human Nutrition and Global Food Supply. Reviews in Fisheries Science. 2013;21(1):22–38.
1. UN. World Economic and Social Survey: Sustainable Development Challenges. Department of Economic and Social Affairs; 2013.
1. Delgado CL. Fish to 2020: Supply and demand in changing global markets. WorldFish. 2003;62.

Global estimation of areas with suitable environmental conditions for mariculture species - PubMed (original) (raw)