Author: M. Austad
Three years have passed since BirdLife Malta last made it to visit the BIOM and Lastovsko otočje teams working on the Lastovo archipelago, and it was amazing to see first-hand the great results that LIFE Artina has achieved!
The number of Yelkouan shearwater nests located on some of the islets has tripled! For sure this is in part due to very systematic and detailed mapping, but also thanks to the successfully implemented invasive species control and eradication of black rats. Rodents predate shearwater eggs and can drastically reduce the number of nests on small islets.
The work is not over though! Rats are good swimmers and can turn up on islets at any point, potentially reversing the successes made. It was great to see the Lastovsko otočje park rangers involved in biosecurity monitoring which will be essential to keep the colonies safe. Some of the Lastovo colonies of Yelkouan shearwaters and Scopoli’s shearwaters are truly unique in their proximity to human settlements.
For example, a stay in Zaklopatica village is a must for any birder or nature enthusiast, during which one can enjoy the nightly spectacle of hundreds of calling shearwaters from the comfort of your balcony, under a perfect stary sky (and Bottle-nose dolphins passing close during the day)! However, this proximity of colonies to human dwellings also brings about management challenges. For example, it was worrying to see that some of the buildings had installed non-shielded lights. Shearwaters are particularly sensitive to light pollution, but by directing lights away from the colony and surrounding sea the negative effect can be mitigated. Likewise, curtains and shutters eliminate the light pollution from windows.
Check out more light pollution-related recommendations here.
When shearwaters leave the nest for the first time, they do so alone without the assistance of their parents. Therefore, they might need some time to train their wings and find their bearings! At this time they are vulnerable to attraction by bright lights and predation by pets, which should be kept off the islet and away from the bay at least during fledging! It would be truly a great next step in the protection of the remarkable Zaklopatica islet to make it only accessible to permitted visits.
The highlight of the visit was perhaps to stay a few days on the island of Sušac, furthest into the azure Adriatic in the Lastovo archipelago. Here we stayed at the lighthouse, where at night the calls of shearwaters echoed through the windows and at day spectacles of migrating marsh harriers, common cranes and hoopoes or the local Peregrines could be enjoyed over coffee break! Sušac is far enough away from any other islands to ensure that no rodents will ever reach it unassisted, making it an exciting prospect for eradication. Complete eradication of rodents would really guarantee that the shearwaters can reach their full potential on the island. Such an endeavour will not be without its challenges though due to rugged and steep terrain covered with dense vegetation. The feral sheep on the island do not help the cause, with shocking levels of soil erosion and degradation on some of the slopes seemingly driven by overgrazing. Island restoration for Sušac is an exciting prospective future project nonetheless!
Finally, shearwaters threw us a surprise! On a night boat-based call survey, we heard Yelkouan shearwaters calling from one of the larger islands in the Archipelago. Here they had not been previously documented to be breeding, probably overlooked due to the size of the island. We returned during the day and found none less than nine incubating Yelkouan shearwaters in the rock crevices, several deep communal burrows which surely hold several more and we only had time to cover a fraction of the island! The increasing number of documented colonies in the archipelago is a testimony of its merit to protection and conservation effort.
Surveying Shearwaters on the Adriatic (Author: M. Austad) Volunteers mapping new Yelkouan shearwater nests (Author: M. Austad)
We wish Lastovo to stay a reminder to the rest of the Mediterranean region on how natural beauty and biodiversity can be maintained, while enjoyed by locals and tourists alike.