Watching Fairy Terns on the Australian coastline is a rare treat
Even if you don’t know a tern from a gull, you have probably noticed terns on beaches, rivers or lakes. In appearance they are like a slimmer, sportier version of a gull. But what really makes them noticeable is their striking method of fishing. They typically hover above the water, looking for an unsuspecting fish, and then dive headlong into the water to catch it with a spectacular splash. The poor fish must feel like it has been hit by a dive bomber.
There are about 20 different species of terns in Australia, and there are few parts of the country where you could never see a tern. Some species can even be seen inland, well away from the coast. One of the most easily recognised terns is the Crested Tern, which is slightly larger than a Silver Gull and has a slightly punkish crest of feathers on its head. Crested Terns are fairly common around most of the Australian coastline, but some species are much rarer.
One rare species that we see fairly often near water in the Perth area is the Fairy Tern (Sternula nereis). These are among the smallest terns, measuring only about 22 to 25cm from the tip of the beak to the end of the tail. They are most commonly seen in summer, as they seem to come south to nest during the warm months and head north in the winter.
Fairy Terns are white with grey wings and a black patch on their head. Their beak is orange-yellow during the breeding season, and the male and female are very similar in appearance.
Birds of a Feather
Fairy Terns are fairly social birds. They nest together in colonies and often fish together in a noisy flock. They look like they are thriving, but studies have shown that they actually have a declining population. It is reported that there are only about 5000 mature Fairy Terns in Australia; about 1600 pairs in WA; a few hundred pairs in both SA and Tas; and just a few pairs in Vic. As a result the species is listed as being Vulnerable.
The reason for their decline is that they nest in shallow scrapes in the sand on beaches, dunes and islands. That leaves them at risk from predators like cats and dogs, disturbances like 4WDs and quad bikes, and buildings that encroach on the foreshore. Oddly, they don’t seem to suffer from overheating on a hot summer’s day. Instead, they are at risk from very stormy weather, which can prevent them from fishing.
There are about 170 Fairy Tern nesting sites in Australia, and we often visit one near Fremantle to watch the family dynamics as the chicks hatch and grow up. Each pair of Fairy Terns works together as a team. One of them minds the nest or chicks, while the other one flies out over the ocean in search of food. When it has caught a small fish, which looks like whitebait, it returns to the nesting site to feed its mate on the nest, or the chicks if they have hatched.
The young, fluffy chicks look very exposed and vulnerable on the beach sand, and you have to wonder how they could possibly survive. However they are speckled brown in colour and are surprisingly well camouflaged, looking just like small rocks on the sand. They also tend to shelter in the shadow of nearby rocks or plants.
In any case, the adult birds are quite territorial and will attack other birds or human beings who come too close to the nesting area, making an agitated ket-ket-ket noise which makes it very clear that you are not welcome.
WHERE TO FIND THEM
Fairy Terns can be found on coastal beaches, sheltered inlets, islands, estuaries, lagoons and harbours. Sightings have been reported along much of the western and southern coasts of Australia, but mostly in WA. They favour sandy areas and generally stay within eyesight of water.
In the Perth area, we have seen them on sandy parts of the Swan River estuary and also on sand dunes near Fremantle. However they are much more common during the warmer months of the year.
The main species that you might confuse with a Fairy Tern is the Little Tern, which has a similar size and shape, but the black stripe through the eye extends right to the beak. There are also different subspecies of Fairy Terns in New Zealand and New Caledonia.
For more information visit http://www.birdlife.org.au/bird-profile/fairy-tern