Why Do Large Dugong Aggregations Persist in Continuous Seagrass Meadows Despite Anthropogenic Disturbances Around Hawar Island, Bahrain

ABSTRACT Spatially explicit aggregations of wide‐ranging marine mammals are important conservation targets. Determining why particular sites sustain such aggregations is crucial to ensure effective science‐based management. In Bahrain, large dugong aggregations (defined as > 50 dugongs) persist predictably around Hawar Island, occupying these waters year‐round at two core aggregation sites. In this study, key environmental, ecological and anthropogenic factors associated with the distribution of these aggregations were evaluated. For this, spatially explicit data from historical records, structured interviews, satellite imagery, habitat cartographies and field ecological surveys were combined and modelled. The two aggregation sites corresponded to winter and summer dugong feeding grounds. There was no indication of localized warm water discharges; surface temperatures at these sites were similar to surrounding waters. The sites were > 80% covered by shallow (3–9 m) stretches of seagrass, encompassed by extensive sheltered meadows (> 400 km 2 ) that were composed of three pioneer seagrass species. A binomial generalized linear model indicated that the presence of seagrass meadows was the primary factor associated with the distributional patterns of large dugong aggregations around Bahrain. These meadows overlapped with historically important fishing grounds and received constant boat traffic, subjecting dugongs and their key habitats to intensifying threats associated with fishing gear and boats. The persistence of large dugong aggregations depends on the maintenance of extensive, unfragmented, healthy seagrass meadows. This requires collaborative regional spatial planning, and the establishment of an effectively managed transboundary protected area that regulates coastal development, net fishing and motorized vessels.