Sooty tern update…

Part of the island’s management plan is in effect about turning back the clock. The southern portion of the island has been identified for restoration. The long term goal is to take this area back, as close as we can, to its original state when first discovered by man. De Trobriand the discoverer of Denis in 1773 left us a fascinating and quite detailed description of the island and its wildlife.

One of the dominant seabird species found on Denis at that time was the Sooty Tern (Onychoprion fuscata). Today one of the first aspects of restoration we are broaching is an attempt to re-establish a breeding population of Sooty terns on the island. Whilst we do not have specific records on the history and fate of the original sooty tern colony, we can draw certain conclusions from the island’s known development history and it seems probable that the bird has not successfully bred on the island for some 150 years.

We are now into the second year of this project and as such work has never been previously undertaken with the Sooty tern we are breaking new ground and learning as we go along. In this second year we have refined our approach following the results of last year and it has definitely been more successful (Previous posts cover the earlier stages of the project see: 19/05/09 and 02/07, 21/09 & 13/10 2008).

The sooty tern project was the focus of much my attention during my last visit to the island and it was most encouraging. On the Thursday afternoon I observed a few birds circling and a couple on the ground but it was on the mornings of Friday and Saturday that things were much more interesting. GIF volunteers Vicki and Georgia have been working steadily on the project and I hope that one or both of them will post soon on their perspective on the project. Both of them were present on Friday morning and the project area was alive with activity. Up to 37 birds were to be seen on the ground at a time with many more circling low over the area and calling. The birds on the ground were observed courting and mating and interacting as if a colony was under formation – it was fascinating stuff. The occasional bird was still seen to attempt to mate with one of the models as well. The next morning was much the same with up to 35 birds being observed on the ground at any time this time with the birds in general occurring in a single group.

It is unlikely that we will see any egg-laying on the island this year as, despite the delay in the onset of the southeast monsoon, egg-laying commenced in the existing Sooty colony on Aride Island in early June. Nevertheless the results this year are much improved from last and we continue to learn more about the bird’s preferences and how we might better design the project next year. According to studies the Sooty tern does not return to breed until it is 6 or 7 years old so it may well be that the birds we are attracting are young adults that are reconnoitring potential breeding locations for next year – let’s hope they keep Denis in mind!!!