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COLLECTION AND INTEGRATION OF MORTALITY DATA IN THE GULF OF MEXICO
Citation:
Fisher, W S. COLLECTION AND INTEGRATION OF MORTALITY DATA IN THE GULF OF MEXICO. Presented at Marine Sentinels Workshop, Tarrytown, NY, October 6-8, 2001.
Description:
(Abstract). Presented at the WPTI Workshop on Marine Vertebrates as Sentinels, 6-9 October 2001, Tarrytown, NY. 1 p. (ERL,GB R840).
Mortalities of aquatic organisms occur frequently due to both natural and anthropogenic causes. In any mortality event, observed mortalities represent only a fraction of the affected individuals. Nonetheless, on-site investigation can provide some indication of the severity and probable cause of an event. Documentation of mortality events across a region can identify spatial and temporal trends that reflect important environmental changes in coastal ecosystems, and might serve as a useful indicator of ecological condition. Aquatic inhabitants of the Gulf of Mexico include organisms with high economic value (fish, shellfish), high
public visibility (marine mammals, corals, sea turtles), and important ecological significance (oysters, submerged aquatic vegetation). The five states along the Gulf of Mexico have a common purpose to preserve and protect these natural resources. However, their efforts to monitor losses have not been integrated. To remedy this, state agencies have joined with federal agencies through the Gulf of Mexico Program to form the Gulf of Mexico Aquatic Mortality Network (GMNET).
The primary objectives of GMNET are to improve the quality of aquatic mortality reporting and documentation across the five Gulf states and to generate a regional geo-referenced database for mortality events. Challenges include establishing high quality data collection, developing a flexible and useful geographic information system for data storage and access, and maintaining both data collection and storage through time. To meet these challenges, GMNET members have collaborated to improve public reporting, interstate communication, and standardization of response approach and documentation. They have developed a 3-tier reporting system that allows all states to use the same format while retaining some flexibility and state control of information. The three tiers provide (1) essential information --- what, when, where, how many, and why; (2) environmental information related to probable cause --- water quality, lesions, weather conditions; and (3) state-privileged information --- chain of custody, litigation information. The first tier can be shared immediately in the common database, the second can be shared after laboratory results are confirmed, and the third is not shared.
Data from GMNETcan be applied toward understanding marine morbidity and mortality at several levels. Tracking mortalities over time and space will provide patterns of occurrence ("hot spots", seasonal events) that might be linked to environmental conditions (altered salinity, algal blooms, fishing seasons). This epizootiological approach can be extended if event data are compared with other major marine events (harmful algal blooms, upwelling, freshwater runoff) and anomalies (anomalous temperatures, currents, turbulence). Events are most often investigated as though the cause was local, with little investigation or understanding of factors that may have originated from or been influenced by, regional and global conditions.
Data generated by GMNET and similar programs (Marine Mammal Stranding Network, Sea Turtle Stranding Network) will provide the background for a broader investigative perspective. Ultimately, high quality data from marine mortality event programs can serve as a long-term indicator for ecological condition, and may also serve as an early warning indicator for adverse environmental changes at local and regional scales.