Saturday, 26 May 2012

26th of May: Sandwich Tern Nest Count

Today we went into the colony to count the Sandwich Tern nests. This was a very serious and well-planned operation. We have a license that enables us to enter the colony. As this causes disturbance to the terns and gulls, we were very careful to spend as little time in the colony as possible, while at the same time being very cautious.

Due to the great numbers of nests we used small pieces of macaroni to mark each one. Before entering the colony, we counted out four bags of 1,000 pieces of macaroni, then we double-counted them to ensure accuracy. This meant that we didn't have to count nests whilst in the colony, we counted the amount of macaroni left afterwards and subtracted this from 4,000.

Having allocated different parts of the colony between four of us, we entered the colony at 6am and began the nest count. We carefully chose this time to cause minimum disturbance to the birds. The conditions were warm and clear, so the eggs would not get too cold. It was low tide, which meant that the birds had plenty of places nearby to settle, preventing them from panicking. And this particular date was chosen because it was late enough that all of the terns have laid eggs, and early enough that all of the chicks hadn't hatched and left the nests.

It was a true privilege to be able to be in the colony. The sound of the adults was incredible. The colony contains a mixture of Sandwich Terns and Black-headed Gulls. The gulls nest first and then the terns move in later, gaining security benefits from being amongst the gulls.

Although close together within the colony, the gull and tern nests are in separate areas. The eggs of both species are different, making it easy for us to count the right species. However the task is still quite stressful because the tern nests are so close together, meaning that we had to watch every footstep carefully. Several nests are tucked under Suaeda bushes too, so we had to look carefully to find every nest as well as watching our steps. We also had to be quick so that we could be out of their way before they became too stressed.

The experience was a mixture of stress, nerves, excitement and honour. Truly amazing. It was a success and has enabled us to find out the exact number of Sandwich Tern nests on Blakeney Point: 3,735. Last year 3,562 were counted (using the same method), which was 35% of the total UK population. This year we may be nearer to 40%.

- Ajay

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