3 Thermal Infrared Remote Sensing and Sea Surface Temperature . . .
67
3.5 Applications to Fisheries & Marine Resources Management
Sustainable fisheries management practices are high priority on the development
agenda for coastal African countries because they directly affect food security for
the local population. Recent advances in data acquisition systems, analysis methods
and communication technologies have considerably promoted the use of satellite data
in the field of fisheries for both, near-real-time support of the day-to-day fishing activities and in the analysis of long-term variability in fish populations. Such synoptic
observation of the sea surface is useful in several ways for the fisheries and aquaculture industries: for resource management, optimization of harvesting strategies,
better understanding of the resource behavior and its spatial/temporal variability,
site protection against recurrent phenomena (e.g. harmful algal blooms) and safety
precautions. Chassot et al. (2011) have compiled a comprehensive review showing
the importance of satellite remote sensing, including TIR images, to characterize the
habitat and ecosystem properties that influence marine resources at large temporal
and spatial scales, thus contributing to the development of an ecosystem approach
to fisheries management.
As mentioned in the previous section, upwelling systems on the west coast
of Africa support large populations of pelagic and demersal fish of considerable
economic importance to regional and global fisheries. According to Pauly and Christensen (1995), coastal upwelling systems represents less than 1 % of the world
oceanic area but accounts for ca. 20 % of the global fish catch.
In the Benguela-Angolan system, the catch of small pelagic fishes fluctuated
greatly after 1980, including a dramatic collapse of the Namibian sardine from 1994
to 1996, despite the application of sound management principles. The observed
variability was to a large extent due to the environment and not to fishing activities,
as it is often the case in other modern fishery grounds. One of the key objectives
of the EU ENVIFISH project (1998–2002; see Barange and Nykjaer 2003) was the
identification and quantification of major environmental conditions that influence
the recruitment and distribution of small pelagic fish stocks in the Benguela-Angola
system. A substantial part of the scientific research in this project relied on TIR
imagery derived for the period 1982–1999, starting with a synoptic-scale description
of the South East Atlantic (Hardman-Moutford et al. 2003), and detailed SST pattern
recognition using neural network method (Richardson et al. 2003).
Following the success of the ENVIFISH project, a similar analysis of the small
pelagic fisheries was performed in the North West African upwelling system through
the EU project NAT-FISH carried out between 2002 and 2005. As for its southern
counterpart, NAT-FISH objectives was to identify and quantify environmental variability related to significant changes in abundance and distribution of small pelagic
fish stocks, but also to investigate the potential of using models in combination with
satellite SST data as a tool for suggesting precautionary measures to be implemented
into responsible fishery management strategies. The project gave the opportunity to
scientists in developing countries to gain insight into the use of long time-series of
satellite-derived oceanographic variables otherwise not available at the level of their
institutions.
67
3.5 Applications to Fisheries & Marine Resources Management
Sustainable fisheries management practices are high priority on the development
agenda for coastal African countries because they directly affect food security for
the local population. Recent advances in data acquisition systems, analysis methods
and communication technologies have considerably promoted the use of satellite data
in the field of fisheries for both, near-real-time support of the day-to-day fishing activities and in the analysis of long-term variability in fish populations. Such synoptic
observation of the sea surface is useful in several ways for the fisheries and aquaculture industries: for resource management, optimization of harvesting strategies,
better understanding of the resource behavior and its spatial/temporal variability,
site protection against recurrent phenomena (e.g. harmful algal blooms) and safety
precautions. Chassot et al. (2011) have compiled a comprehensive review showing
the importance of satellite remote sensing, including TIR images, to characterize the
habitat and ecosystem properties that influence marine resources at large temporal
and spatial scales, thus contributing to the development of an ecosystem approach
to fisheries management.
As mentioned in the previous section, upwelling systems on the west coast
of Africa support large populations of pelagic and demersal fish of considerable
economic importance to regional and global fisheries. According to Pauly and Christensen (1995), coastal upwelling systems represents less than 1 % of the world
oceanic area but accounts for ca. 20 % of the global fish catch.
In the Benguela-Angolan system, the catch of small pelagic fishes fluctuated
greatly after 1980, including a dramatic collapse of the Namibian sardine from 1994
to 1996, despite the application of sound management principles. The observed
variability was to a large extent due to the environment and not to fishing activities,
as it is often the case in other modern fishery grounds. One of the key objectives
of the EU ENVIFISH project (1998–2002; see Barange and Nykjaer 2003) was the
identification and quantification of major environmental conditions that influence
the recruitment and distribution of small pelagic fish stocks in the Benguela-Angola
system. A substantial part of the scientific research in this project relied on TIR
imagery derived for the period 1982–1999, starting with a synoptic-scale description
of the South East Atlantic (Hardman-Moutford et al. 2003), and detailed SST pattern
recognition using neural network method (Richardson et al. 2003).
Following the success of the ENVIFISH project, a similar analysis of the small
pelagic fisheries was performed in the North West African upwelling system through
the EU project NAT-FISH carried out between 2002 and 2005. As for its southern
counterpart, NAT-FISH objectives was to identify and quantify environmental variability related to significant changes in abundance and distribution of small pelagic
fish stocks, but also to investigate the potential of using models in combination with
satellite SST data as a tool for suggesting precautionary measures to be implemented
into responsible fishery management strategies. The project gave the opportunity to
scientists in developing countries to gain insight into the use of long time-series of
satellite-derived oceanographic variables otherwise not available at the level of their
institutions.