The first sign we were coming close to the Chagos-Archipelago was a plethora of seabirds circling our boat. This phenomenon is well known from old maritime literature, where masses of seabirds signalised imminent landfall. Nowhere we went so far was this phenomenon as pronounced, clearly an indication that we were getting closer to a very special area.

Seabirds live mainly or predominantly above, on or in the ocean and also find their food there. To breed or build their nests they look for remote islands in the middle of the ocean where they are not disturbed. On those islands they mate, build their nests or just lay their eggs on certain places. So they are very sensitive to disturbances from outside, especially through humans. Now the Chagos-Archipelago is reserved for nature and therefore left to seabirds and coconut-crabs.

On some islands, like almost all in the Salomon-Atoll, you can find rats, which were introduced by humans. That is the reason why you hardly find any ground-breeding birds because their eggs would be eaten. Or they build their nests higher up to escape those enemies. Scientific research confirms that on islands with rats the nests are built much higher than on islands without rats.

Overall there are 17 species of seabirds on the Chagos islands, of which we found at least 7. At Ile Takamaka we observed lots of red-footed boobies (Sula sula, picture 1-4), which just started to build nests and started mating (picture 5-8). Lots of fights in the air (picture 3) for branches and twigs are common for boobies.

01_red-footed_booby_flying-Sula_sula
01_red-footed_booby_flying-Sula_sula
02_red-footed_booby_(Sula_sula)_looking_at_us
02_red-footed_booby_(Sula_sula)_looking_at_us
03_red-footed_booby_flying-Sula_sula
03_red-footed_booby_flying-Sula_sula
04_red-footed_booby_(Sula_sula)_sleeping_on_tree
04_red-footed_booby_(Sula_sula)_sleeping_on_tree
05_red-footed_booby_(Sula_sula)_preparing_to_mate
05_red-footed_booby_(Sula_sula)_preparing_to_mate
06_red-footed_booby_(Sula_sula)_right_before_mating
06_red-footed_booby_(Sula_sula)_right_before_mating
07_red-footed_booby_(Sula_sula)_mating
07_red-footed_booby_(Sula_sula)_mating
08_red-footed_booby_(Sula_sula)_after_mating
08_red-footed_booby_(Sula_sula)_after_mating

They often also do not have enough time to eat their fish because great frigatebirds (Fregata minor, Picture 22-24) try to steal the fish. Although frigate birds can catch fish and other prey from the water surface they have a hard time to start from water. That's why they prefer to wait until other birds catch some fish and then chase them to eat their fish.

The red-footed boobies prefer to sit and breed on native trees, also because they easily loose their footing on the coconut trees and can not build their nests there. If you walk around the islands most of the birds sit on the native trees, almost none on the palm trees.

Probably because of the rats we didn't find any brown boobies (Sula leucogaster, Picture 12-15) on Ile Takamaka and Ile Fouquet. They are ground-breeding birds and usually build their nests in large colonies. But they were always accompanying us when we made excursions with our dinghi. We also found big groups of brown noodies (Anous stolidus, picture 16-18) on the beach which usually flew very close to our heads. Those build their nests on bushes and trees or on the ground. We could observe black-naped terns (Sterna sumatrana, picture 19) during their courtship and see white terns (Gygis alba, picture 20-21) and white-tailed tropic birds (Phaethon lepturus) circling above.

08_red-footed_booby_(Sula_sula)_after_mating
08_red-footed_booby_(Sula_sula)_after_mating
09_red-footed_booby_taking_off-Sula_sula
09_red-footed_booby_taking_off-Sula_sula
10_red-footed_booby-Sula_sula
10_red-footed_booby-Sula_sula
11_red-footed_booby_over ocean-Sula_sula
11_red-footed_booby_over ocean-Sula_sula
12_brown_booby_adult-Sula_leucogaster
12_brown_booby_adult-Sula_leucogaster
13_brown_booby_adult-Sula_leucogaster
13_brown_booby_adult-Sula_leucogaster
14_brown_booby_juvenile-Sula_leucogaster
14_brown_booby_juvenile-Sula_leucogaster
15_brown_booby_juvenile-Sula_leucogaster
15_brown_booby_juvenile-Sula_leucogaster
16_brown_noody-Anous_stolidus
16_brown_noody-Anous_stolidus
17_brown_noody_flock-Anous_stolidus
17_brown_noody_flock-Anous_stolidus
18_brown_noody_flying-Anous_stolidus
18_brown_noody_flying-Anous_stolidus
19_black-naped_tern-Sterna_sumatrana
19_black-naped_tern-Sterna_sumatrana
20_white_tern_flying-Gygis_alba
20_white_tern_flying-Gygis_alba
21_white_tern_flying-Gygis_alba
21_white_tern_flying-Gygis_alba
22_Great_frigatebird_female_subadult_Fregata_minor
22_Great_frigatebird_female_subadult_Fregata_minor
23_Great_frigatebird_male_Fregata_minor_
23_Great_frigatebird_male_Fregata_minor_

White terns live monogamous and lay their eggs just somewhere on the ground or in crotches of trees.

In the Chagos-Archipelago the seabirds still find optimal conditions to live and breed. We hope they will be undisturbed at this place for a long time to come.

project manaia

Krüss Mikroskope