Diving the dropoff and working with seabirds - BIOT 2014 Expedition Day 4

by Anonymous (not verified) on

We’re settling into a routine on board now so deploying for the morning dive was somewhat slicker than yesterday’s attempt. Despite a couple of boats being out the water for running repairs and the distraction of a playful pod of dolphins en route we still plunged in for the days first dive well ahead of schedule. We could hear the dolphins whistles throughout our submersion but they’re really wary of divers and only ventured close enough to be visible on a couple of occasions. An invisible choir for our listening pleasure whilst working the reefs. The site we chose was a busy one, rich with corals and clouds of fish. From previous dives here we know that the place is prone to strong currents and this is evident in the abundance of anemones. They like to have the tentacles wafted by the moving water. With the anemones come the inevitable anemonefish. And special for this site, a large number of these beautiful little anemone symbionts are the endemic Chagos Anemonefish. These are not the only fish that provided a spectacle while we worked, a small snapper proved to be very tame and kept flitting from dive pair to dive pair for company. More to come on the marine side of things tomorrow. 

For today I thought I’d ask Pete Carr to fill you in on the birding programme in a little more detail so here are a few words from him - Jon Slayer:

“Today presented the opportunity for me to introduce Loius to a different island in the Chagos and to show him some techniques for monitoring breeding seabirds. An early start saw us dropped on the beach.  Fortunately there was no requirement to swim ashore.  We then walked the circumference of the island counting the number of nesting Red-footed Booby using a standard technique called Apparently Occupied Nests (AONs). I am looking at trying to confirm the peak breeding period for this species in the Chagos (they nest throughout the calendar year) so I take AON a stage further and try to ascertain at what stage of the breeding cycle the birds are at, e.g. eggs, small chicks, large chick, etc.  This is possible for many nests that are low down on trees, but does normally involve wading out in to the sea to look back at the shoreline!  This expedition’s survey data will be combined with counts I have made at other times of the year to and unravel the breeding phenology of this species and, whether it is linked to any oceanographic events.

Chagos; Connect Chagos; Chagos Ambassador; Trainee
Louis Elyse learns the ropes on the bird monitoring project

Louis witnessed first-hand some of the dangers and challenges facing seabirds, not only in the Chagos but throughout the world.  The first example was of a small chick that had fallen from its nest on to the beach and was being devoured by crabs.  Whilst sad and grisly this is a natural process.  The distressing example of the challenges facing seabirds worldwide was of an adult Red-footed Booby hanging upside-down, dead in a tree.  Despite there being no fishing in the Chagos Marine Protected Area, this bird had become tangled in monofilament fishing line, carried it back to its nesting/roosting tree where it became snagged and died, likely through exhaustion from trying to free itself.

Despite the challenges to the breeding seabirds, they are faring well in the Chagos.  Today’s example of the importance of the Chagos for seabirds comes from the Red-footed Booby.  Throughout the Indian Ocean breeding colonies of this species have declined or totally disappeared.  Historically this was the case in the Chagos too but things are changing.  In the first major survey of the breeding seabirds in 1996 the island Loius and I looked around today held no breeding Red-footed Booby.  Today, thanks to some surviving magnificent Takamaka trees on the shoreline that provide a suitable nesting platform, this island had a minimum of 169 breeding pairs.  Globally there are very few oceanic islands, atolls or archipelagos that can boast of increasing or recently increased breeding seabird numbers; the British Indian Ocean Territory can.

The Chagos Archipelago is a sanctuary for breeding seabirds in an ocean and world where seabirds are generally not faring well.  Everything should be done to protect this breeding stock and where possible, facilitate an environment in which they can increase breeding numbers.  With sympathetic shoreline habitat management that would increase native trees that seabirds prefer to breed in e.g. Takamaka, Pisonia and Barringtonia, coupled with an invasive mammal eradication programme, the British Indian Ocean Territory could be the Indian Ocean reservoir of seabirds to repopulate protected but impoverished islands elsewhere.  Ecological improvement of oceanic islands is not a green dream; it is occurring worldwide and has already been achieved in other UK Overseas Territories.  The time must surely be near where the will and the finances will become available to allow the ecologically devastated islands of this wonderful archipelago to be restored to something of their former glory.”

Select a blog

ZSL London Zoo

A blog for lovers of ZSL London Zoo, bringing you extraordinary animal facts and exclusive access to the world's oldest scientific zoo.

ZSL Whipsnade Zoo

Do you love wildlife? Discover more about our amazing animals at the UK's biggest zoo!

Conservation

We're working around the world to conserve animals and their habitats, find out more about our latest achievements.

Science

From the field to the lab, catch up with the scientists on the cutting edge of conservation biology at ZSL’s Institute of Zoology.

Education

A day in Discovery and Learning at ZSL is never dull! The team tell us all about the exciting sessions for school children, as well as work further afield.

Working for Wildlife

Ever wondered what a typical day as a zookeeper looks like, or what it's like to be a videographer at ZSL? Now you can find out!

Artefact of the month

Every month, one of the pieces held in ZSL’s Library and at ZSL Whipsnade Zoo will feature here as Artefact of the Month.

Wild About Magazine

Read extracts from ZSL's award winning members' magazine, Wild About.

ZSL Shop

Get updates on our latest ranges, be the first to hear about special offers, and find the perfect gift for animal lovers!

Chagos Expedition

The Chagos archipelago is a rare haven for marine biodiversity. Hear from the team about our projects to protect the environments in the British Indian Ocean Territory (BIOT).

Nelson's Island Expedition

ZSL Institute of Zoology researchers are embarking on an exciting fieldwork expedition to Nelson’s Island in the Chagos Archipelago. Throughout the month, the team will share their research and experiences on an uninhabited tropical island!

Asia Conservation Programme

ZSL works across Asia, from the famous national parks of Nepal to marine protected areas in the Philippines. Read the latest updates on our conservation.

Remote Sensing in Ecology and Conservation

An Open Access journal for research at the interface of remote sensing, ecology and conservation.