Sooty Tern Summary 2008 (Part 1).

The sound system has been dismantled and half of the models packed away. The remaining models, having been left out as a feature for the guest’s nature walk, will soon now also be removed as video footage of the project has been added to the evening presentations.

As this first season of the 4-year programme has now closed it is appropriate to summarise the build up to and background of the project.

I first became interested in Sooty Terns (Onychoprion fuscata) whilst working on Cousine Island (1993-96). The abundance of the birds displaying and swooping low over the island, led me to believe that they must be nesting in a small colony somewhere or on the verge of forming a colony. Thorough checks during the seasons of 94 and 95 showed however that there was no colony on the island[1].

I subsequently met Professor Chris Feare, the leading expert on the species, whilst working for the Division of Environment in 1997 and we discussed the possibilities of attempting a re-establishment of a colony on island using models and colony noise playback – something that Chris had been hoping to try for some time. The issue was finding a suitable island - i.e. one that had formerly hosted Sooties, which was alien predator free and manageable in terms of resident human resource capacity and ability to prevent poaching of a newly-established colony.

Hence when GIF started to work with Denis Island in 2006 I proposed the project as part of the island’s broader ecosystem rehabilitation project. The owners were interested in the idea so I developed a concept paper in January 2007 with project outline, budget and a short list of 3 potential locations on the island. The owners approved the project and so I commenced liaison with Chris on how we could proceed.

Chris visited Denis in June 2007 and based on his advice, coupled with the islands existing Land Use Plan (LUP) criteria, we selected an area on the south west coast (see map) for the pilot project. The factors effecting the site selection included: optimal distance from the runway and hotel, a location on the west coast which suited the birds’ typical displaying activity on the nearest colony on Bird Island, compatibility with the restoration zone of the LUP and the availability of suitable flight path. Sooty terns are very graceful and efficient long distance fliers but prefer to have reasonable flight paths into their landing area. The island’s new LUP does not allow for vegetation within 25 metres of the high water mark to be removed. The final area was chosen because there is an old abandoned building on the coast there, the garden of, which provided an existing flight path through the coastal vegetation.

It is known from other colonies that Sooties prefer to nest in open ground with flat herbaceous vegetation. The area chosen consisted of a densely vegetated abandoned coconut plantation and so the next stage was to clear the area and make it suitable. Denis has an existing approval from Government to fell up to 50 coconut trees a week in order to harvest the heart of palm for the local hotel market and so it was decided to use this quota in a focused manner in the area in question. The area cleared is a little less than 2 hectares and constitutes approximately 1.5% of the island’s surface area.

It was initially intended to undertake the work from August 2007 onwards but labour shortages meant that work only commenced in January 2008. The area was cleared by the end of April which whilst it meant it was ready in time for the season also meant the opportunity to mange the ground vegetation in the desired manner through the rainy season was lost.

During this period other technical issues were also addressed in terms of the purchase of the necessary equipment and the identification of a project partner and volunteers from Reading University in the UK.

This project to re-establish a sooty tern colony on Denis Island represents a world first and as such it was determined from the offset to undertake it to strict scientific criteria. I will cover the technical preparation and implementation phases of the project in a subsequent post. So check back regularly for that and other updates!


[1] A small colony of Sooties did naturally re-establish itself on the island in 2003.