Seminar - Daniel Harrison - The Possibility of Increasing Small Pelagic Fish Yields in Morocco

Wednesday 13 April 2011, 4.00 pm - 5.00 pm
Civil Engineering Conference Room

Daniel P Harrison
School of Civil Engineering
University of Sydney

Abstract:
Moroccan small pelagic fish appear to be harvested at, close to or above their maximum sustainable yield. In the absence of environmental change, sustainable wild catch along the Moroccan coast can only be increased by human intervention. This intervention could come in the form of purposeful introduction of macronutrients to increase the primary and secondary production leading to increased food availability for small pelagic fisheries, producing a predicted increase in stock size. Thus producing an expansion of the fishing grounds into the oligotrophic oceans. Previous experiments have shown that technology known, as Ocean Nourishment is effective in encouraging phytoplankton growth in nutrient depleted waters of the Canary Current. Seawater collected from around 20km out to sea in several locations along the Moroccan coast were kept in simulated natural conditions of temperature and sunlight by immersion in temperature controlled water baths outdoors, near to the point of collection. Macronutrients were added to the samples and significant phytoplankton growth was observed over control samples.

With information from previous research and experiments we show how the Ocean Nourishment can be engineered to create a new area of primary productivity. We show that the location, extent, and concentration of the enriched phytoplankton / zooplankton patch can be controlled to an acceptable degree by adaptable engineering of the injection of nutrients. It follows that if the enriched zone is appropriately located, small pelagic fish populations should expand into the new productive area thus relieving food limitation to growth allowing an expansion of the fishery. As the location of new fishery areas created is under the control of the operators, access to the additional fish created could be controlled by a licensing system. Enrichment will be most effective away from the coast where upwelled nutrients have been depleted. Therefore licensing of new productive areas will be most attractive to industrial fishing operators. A licensing system might be construed that moves some industrial fishing into the newly created productive zones and allows an expansion of the artisanal fishery which operates closer to the coastline. In this manner Morocco could increase its sustainable catch of small pelagic fish with some of the benefit going to poor artisanal fisherman most in need of additional protein and income.


Biography
Daniel completed his bachelor degree in Engineering at the University of Sydney in 2003. During his studies he was a member of the university’s Ocean Technology Group (OTG). His work with the OTG included an engineering honours thesis on a high resolution underwater sonar that was in development with the Royal Australian Navy. Since graduating he has continued work with the OTG in areas such as enhancing carbon storage in the oceans by new technologies including Ocean Nourishment, and Ocean Alkalinity Shift. From 2007 -2010 Daniel was a visiting scholar at the University of Southern California where he focused on GIS applications in research and management for both fisheries and aquaculture in collaboration with the NOAA South West Fisheries Science Centre, the Inter American Tropical Tuna Commission, and NASA . His work included studies of the tuna species of the Pacific Ocean and shark species of the California Current System using NASA generated satellite imagery. In 2010 Daniel returned to the University of Sydney to complete a Masters in Engineering Research. Daniel has published 1 peer reviewed paper, several technical reports, holds a Australian Innovation Patent on a method for aggregating and fattening fish, and has presented at over 20 conferences around the world.