It is noddy breeding season on Cousin Island Special Reserve and thousands of nesting Lesser and Brown Noddys have flocked to the island. The seabirds can be seen and heard all over the island; engaging in courtship, nesting on trees and rocky cliffs, and hovering and dipping into the ocean to catch prey.
It is Noddy breeding season on Cousin Island
Cousin is an Important Bird Area (IBA). It is globally recognized as significant for conservation of Seychelles’ endemic and native land birds, and as a key roosting site for large seabird colonies.
It is home to seven nesting seabird species; Lesser and Brown Noddys, Wedge-tailed and Tropical Shearwaters, White and Bridled Terns, and White-tailed Tropicbirds.
They are a major ecotourism attraction. Because Cousin is free from invasive predators such as cats and rats, birds can be observed up close, making it an ornithological dream come true.
However, the seabirds are not just picturesque additions to the island. They are key indicators of ocean health. With their wide distribution and dependence on marine ecosystems, they are used worldwide as invaluable sentinels of ocean health.
Cousin warden looking at nesting Lesser Noddys
By monitoring breeding colonies, scientists can gather insights into the state of the oceans. This includes the impacts of overfishing, pollution, climate change, and shifts in ocean currents or feeding grounds.
The dynamic relationship between seabirds and their nesting environments can also be used to assess ecosystem health. Monitoring can likewise show when things are going well. The study of the population and migratory patterns of birds that feed on fish, for instance, can provide viable indicators of the health of the species they eat.
Cousin Island offers a prime example of successful seabird conservation. Its habitats, comprising three zones – the plateau forest, the granitic hill, and a small mangrove area – are vital locations for censuses, surveys, and breeding success assessments. From these, trends and patterns can be seen over time.
Different survey methods are employed for monitoring. Nest checks, general seabird censuses, and flush counts are among the techniques used. Monitoring involves marking and numbering nests, checking for eggs or chicks, and observing adult presence. The data collected provides estimates of breeding pairs and insights into overall colony health.
A nesting Lesser Noddy
Seabird censuses are conducted during different seasons to gather comprehensive data. Some seabirds are counted based on the presence of eggs or chicks, while others require visual inspections. Flush counts, involving the disturbance of nesting areas, count birds in flight, while call backs are used for some species like shearwaters, in addition to physical searching of burrows.
Yearly seabird monitoring is conducted on the island. This yields valuable data on the populations and behaviours of the various seabird species. It is one of the most significant activities on the annual conservation calendar, involving both staff and volunteers.
Monitoring and censuses on the island use standardised methods laid out in the Seabird Monitoring Handbook for Seychelles published by Nature Seychelles. The handbook contains field-tested methods for monitoring and provides robust data for conservation