Today's Edition
Mays Ibrahim (ABU DHABI)
The islands surrounding Abu Dhabi are not only breathtaking, but also crucial havens for migratory terns. Positioned strategically in the Arabian Gulf, these picturesque landscapes offer vital breeding grounds, contributing significantly to the conservation of these seabirds and the overall health of the marine ecosystem.
Conducive Ecological Conditions
Abu Dhabi boasts most of the islands in the UAE and the Arabian Gulf, drawing a concentration of terns during the breeding season, according to the Environment Agency – Abu Dhabi (EAD).
In a statement to Aletihad, EAD highlighted the unique combination of ecological features that make the emirate’s islands a safe haven for these otherwise pelagic species that predominantly live at sea.
Many of these islands are relatively remote, which ensures minimal human disturbance and interference, a factor that is crucial for the successful nesting and rearing of turn chicks. They are also usually free from common predators, like foxes or cats, which could pose a threat for ground nesting birds.
Their surrounding waters are teeming with marine life, providing an abundant food supply that is crucial for the terns to sustain their chicks. Additionally, the variety of nesting habitats on the islands, from sandy shores and dwarf vegetated areas to rocky outcrops, caters to the specific nesting preferences of different tern species.
Tern Species Observed in Abu Dhabi
Several tern species make Abu Dhabi’s islands their breeding grounds, each with unique nesting behaviors.
The Swift Tern (Thalasseus bergii), a less common breeder found in significant numbers only on one offshore island, nests in tightly packed colonies. The Lesser Crested Tern (Thalasseus bengalensis), a more common breeding species, nests primarily on sandy offshore islands where it lays a single egg in a depression.
The Bridled Tern (Onychoprion anaethetus) is one of the most common and widely distributed tern species that is somewhat tolerant to human presence. It’s known for its preference for nesting under dwarf shrubs, and on some islands it is seen nesting on low hills and rocky areas. The presence of vegetation is essential for this species to nest, as it lays a single egg hiding it under the shrubs.
The White-cheeked Tern (Sterna repressa), another common species, nests in sandy areas or on hard substrates, often lining their nests with twigs and small stones. Typically, 2 to 3 eggs are laid. They are also seen nesting on gravel-like material obtained from dredging and deposited nearshore. Saunders’s Tern (Sternula saundersi) breed on nearshore islands, offshore islands as well as coastal areas in very loose colonies.
Indicators of Marine Ecosystem Health
The presence of tern breeding grounds has a positive impact on the overall health and stability of the local ecosystem.
EAD explained that terns serve as key indicators of marine ecosystem health; a thriving tern population signals a thriving marine environment.
These sea birds also support the biodiversity of the region, as their nesting activities contribute to nutrient cycling on the islands; their guano (droppings) enriches the soil, supporting plant life and a variety of other species.
Threats and Conservation Measures
Several threats endanger the vital breeding sites of migratory terns, including habitat loss from development and construction activities, along with human disturbance in the form of increased tourism, recreational activities, and illegal egg collection.
Climate change, marked by rising temperatures and sea levels, also poses a risk to habitat availability and breeding success, while the introduction of non-native predators, such as rats or cats, can devastate tern populations.
However, EAD has taken an active role in addressing these threats through implementing several conservation measures. Many key islands are designated as Important Bird Areas (IBAs) and are part of Marine Protected Areas (MPAs) with restricted access during critical breeding seasons.
In addition to conducting awareness campaigns to educate the public, EAD also regularly monitors tern populations and their habitats, which helps in understanding their needs and the challenges they face, allowing for better-informed conservation strategies.
