Five-year rolling trend in fisheries catch-to-biomass ratio (declared window)
| Object type | Damage Signal |
|---|---|
| SIGNAL Earth ID | DS-00413 |
| Observable type | Dissolved oxygen concentration |
| Unit | mg/L (milligrams of oxygen per liter of water) |
| Temporal structure | Frequent |
| Monitoring backbone | — |
Five-year rolling trend in fisheries catch-to-biomass ratio (declared window) The five-year rolling trend in fisheries catch-to-biomass ratio is an environmental indicator derived from measurements of dissolved oxygen concentration in marine ecosystems. This signal reflects changes in the balance between fish catches and the underlying biomass, providing insight into the sustainability and health of exploited fish populations over time. It is particularly relevant in the context of global fisheries management and marine ecosystem monitoring.
This signal captures state changes within the ocean domain, where dissolved oxygen levels influence fish biomass and catch rates. Fluctuations in dissolved oxygen can affect fish metabolism, distribution, and survival, thereby impacting fisheries yields. Understanding trends in the catch-to-biomass ratio helps assess the resilience of marine populations to environmental stressors.
By examining this signal globally, scientists can identify regional variations and temporal patterns in fisheries productivity, supporting broader assessments of marine ecosystem status and informing scientific research on ocean health.
Geographic / System Context
[edit]The signal encompasses a global geographic scope, covering marine ecosystems across various ocean basins, climatic zones, and marine ecoregions. It reflects conditions in diverse marine environments where fisheries operate, including coastal zones, continental shelves, and open ocean areas. These regions vary in their physical, chemical, and biological characteristics, influencing dissolved oxygen concentrations and fish population dynamics. The global perspective allows for comparative analyses across different marine systems and supports understanding of large-scale oceanographic processes affecting fisheries.
Monitoring and Measurement
[edit]Monitoring of this signal relies on frequent measurements of dissolved oxygen concentration in marine waters, expressed in milligrams per liter (mg/L). Observations are typically obtained through a combination of in situ sampling using oceanographic instruments such as oxygen sensors and autonomous platforms, as well as remote sensing technologies where applicable. Scientific institutions and marine research programs contribute data that inform the estimation of catch-to-biomass ratios by integrating oxygen measurements with fisheries catch records and biomass assessments. Standardized measurement protocols ensure consistency and comparability across regions and time periods.
Within the SIGNAL system, this phenomenon is treated as a defined environmental signal whose boundaries and measurement conventions are described below.
Signal Definition
[edit]The five-year rolling trend in fisheries catch-to-biomass ratio quantifies the temporal change in the ratio of fish catch to fish biomass over a five-year moving window. It is derived from the observable dissolved oxygen concentration in marine environments, serving as a proxy for the physiological and ecological conditions affecting fish populations. This signal represents a state change within the ocean domain, indicating shifts in the balance between fish removal through catch and the standing biomass that supports sustainable fisheries.
Boundary Conditions
[edit]Boundary inclusions encompass marine dissolved oxygen concentrations measured within the global ocean, particularly in regions where fisheries are active and biomass data are available. The signal includes temporal data aggregated over consecutive five-year periods to capture rolling trends. Boundary exclusions involve measurements outside the marine environment, such as freshwater or estuarine systems, and data lacking sufficient temporal resolution or spatial coverage to support trend analysis. Additionally, the signal excludes catch-to-biomass ratios derived without corresponding dissolved oxygen observations or those from unverified fisheries data sources.
Aggregation Semantics
[edit]Geographically, the signal aggregates data across marine ecoregions, ocean basins, and climatic zones, enabling spatial comparisons and identification of regional patterns. Temporally, it employs a five-year rolling window to smooth short-term variability and highlight medium-term trends in fisheries catch-to-biomass ratios. Cross-signal aggregation is not specified for this signal, focusing instead on its standalone interpretation. Aggregation methods ensure that the signal reflects integrated ecosystem states over relevant spatial and temporal scales, supporting robust environmental assessments.
Observational Status
[edit]Current monitoring efforts provide frequent dissolved oxygen measurements globally, supporting the calculation of this damage signal. However, the monitoring backbone and data integration frameworks are still under development. Future SIGNAL releases may enhance spatial resolution, incorporate additional fisheries and biomass datasets, and refine aggregation methodologies. Continued data collection and methodological improvements will strengthen the signal's utility for tracking marine ecosystem health and fisheries sustainability.
Related Signals
[edit]- None specified
Key Associated People
[edit]- M. L. D. Palomares (Sea Around Us / University of British Columbia) [Lead author]