The FOCAL Point
Dr. Frank Hernandez and Heather Fletcher, DISL
 

Economically important fishes have dominated the coastal battleground for the past three decades. This environment experiences highly variable physical conditions of wind, wave, temperature and salinity - and in three dimensions! FOCAL (Fisheries Oceanography of Coastal Alabama), a new DISL research initiative funded through the Marine Resources Division of ADCNR, is examining the relationship between environmental variability and marine fisheries resources, with a specific focus on the early life stages (eggs and larvae) of fishes. The program uses an ecosystem-based approach to address the linkages between the physical and biological processes that affect the survival of fish larvae and therefore the resulting fishery.
 

	The team drops a Mininess, a multiple net sampling system, in the water.

One of the major goals of FOCAL is to establish a monitoring program from inside Mobile Bay to approximately 35 miles offshore in support of a long-term fishery-independent study of selected economically important species in coastal Alabama. Plankton samples are collected at various depths along the transect throughout the year. The vertical distribution of these early life stages within the several layers of the coastal waters is one of the least studied aspects of the community. Fish eggs and larvae, or ichthyoplankton, along with zooplankton (which include ichthyoplankton predators and prey) are sorted from the samples, counted and identified. These data are then used to estimate the abundance, distribution, seasonality and species composition of the ichthyoplankton and their potential predators and prey (M. Graham, F. Hernandez and S. Powers, co-PIs). Such information is crucial in assessing linkages between the physical environment and larval supply, survivorship, recruitment, and fisheries production. In addition, long term monitoring of ichthyoplankton and zooplankton assemblages can serve as an indicator of ecosystem health and provide new data sets for the various fishery management models that exist.
 

The FOCAL program also supports additional biological sampling efforts across the shelf that target food web pathways important to fisheries resources. For example, the larger bottom-living invertebrates are collected along the coast with benthic grabs to assess the distribution, abundance and habitat associations of potential food resources for juvenile and adult fishes (K. Heck, co-PI). Additional sampling events measures the abundance, type and productivity of marine microalgae (microscopic single-celled plants) and bacteria to assess variability in food quality for the fish and zooplankton that eat them (H. MacIntyre and R. Kiene, co-PIs).
 

All of these biological measurements are supported by the continuous measurement of physical data (salinity, temperature and current velocity) from a mooring station donated by Conoco Phillips approximately 11 miles offshore (K. Park, co-PI). Because currents and the physical properties of coastal water masses can affect the distribution and survivorship of fish early life stages, these data will be valuable in characterizing water column stratification and vertical mixing processes.
 

	FOCAL will provide a solid foundation for the research that will be conducted in the Richard C. Shelby Center for Ecosystem-Based Fisheries Management scheduled to open at the Sea Lab in January 2009.
Chaetodipterus faber or the Atlantic spadefish