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Date: June 2010 - Polynesia
ECO-FENUA IN BRIEF
Five migratory birds are included in protected species in Polynesia.
The International Migratory Birds Day, last May 8, made it possible to count the five species that leave our islands every year to go on reproduction sites, which often are several thousands of kilometers away.
They are the - Alaska curlew (kivi, keuhe, etc in Polynesian languages) - the wandering knight (uriri, torea, tuki, etc) - the tawny plover (torea, ti'afe, etc) - the Sanderling sand piper (tiri, tuki, etc) - the New Zealand cuckoo ('arevareva, kurevareva, kakaveka, oroveo, etc).
Some of them cover amazing distances (between 10 and 15,000 km) to fly to Alaska or Siberia! As to the New Zealand cuckoo, he flies only the 5,000 km which separate him from his country of origin.
The Polynesian organizations for the protections of threatened species are particularly attentive to these birds, and namely to the Alaskan curlew, very present in the Tuamotu. It feeds on small mollusks and other crustaceans along the beaches and streams. It is however very vulnerable, dogs and cats being its main predators.
 Down with killer snails!
As you see, when you want to do good, you better consider poorly controlled chain consequences.
In 1974, the giant African snail, Achatina fulica, was introduced in Polynesia. This very sizeable specimen adapted perfectly, but caused major damages to agriculture and at the same time to some of their smaller "cousins".
To fight this real scourge, a dozen years ago, a carnivorous snail, the Euglandina Rosea, was introduced on a trial basis to stop the damages caused by the Achatina Fulica on the island of Moorea. A few seasons later, we became aware that this very voracious species had eliminated no less than 52 of the 58 known species of gastropods. Its legendary appetite being what it is, it simply ate most of its "cousins" including the giant African snail, keeping only alive two or three endemic species in Tahiti and the Society Islands.
Which species are we going to import today to find this new "serial killer"?
Brown seaweed, Turbinaria ornata: A new scourge spreading in the Tuamotu lagoons
 You all must have seen while going swimming this brownish large sea weed, especially dense in the lagoons of the Polynesian high islands, it is the Turbinaria Ornata.
Absent in the Tuamotu lagoons until the 1990's, it is now omnipresent on several atolls, where it is considered as a "very invading species".
This "migration" to the atolls is delicate to explain, but we suppose that it is due to a phenomenon of drifting of the "thalles rafts" floating on the surface of the oceans. These floating seaweeds decomposing at the surface of the water have been recently studied and we observed that the "thalles" keep their fertility during their long drift according to the winds and swells. Cyclonic phenomena and the big swells of these past few years have spread the Turbinaria Ornata brown seaweeds all the way to Polynesia.
On the atolls concerned, a campaign is being prepared to pull out these seaweeds whose density is such that it seems to cause nuisances on the corals. Once they are pulled out, these seaweeds could be turned into a first class organic fertilizer.
See other articles under the heading Eco-Fenua:
 The Lavatubes
Perliculture
Agriculture
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