For many of Bird Island’s Sooty Terns incubation is now over, and in parts of the colony nests contain small downy chicks, with black eyes wide open and apparently aware of their surroundings, but not yet running away from their nests. Their parents are extremely busy, searching for food far out to sea and also protecting their young when attendant Mums or Dads are in the colony.
Quite naturally they regard us as a potential threat and make all efforts to defend their young when we are working in the colony. As a result, in addition to having to protect our skins against the intense sun and desiccating south-east wind when we are doing our research, we have to protect ourselves against attacks from the birds.
Our ankles and lower legs are particularly vulnerable. They are continually being bombarded. Rather stupidly, Christine and I wear shorts but Dylan, our young afternoon assistant, does wear long trousers and also cardboard gaiters strapped around his lower legs – the sensible option. Christine and I are nevertheless very careful to wash our leg scratches and stabs, and disinfect them as soon as we can on our return to our “office” (one of the hotel chalets).
Our heads need protection from the stabs and body blows that the birds inflict. We always wear hats but sometimes the bills manage to penetrate the material and reach our scalps, so now that hatching time has arrived we both wear two hats, one inside the other. Even this is not entirely foolproof. The island’s Conservation Officer, Roby Bresson, places “No entry” signs around the colony each year. For those like us who are foolish enough to ignore these signs, perhaps “Hard hat zone” signs would also be appropriate! In reality though this could be bad for the birds and I hate to think how a Sooty Tern with a headache would treat us!
We also need protection for our eyes. Dylan and I routinely wear spectacles but Christine has to wear sunglasses in the colony. Sometimes Sooty Terns take off immediately in front of us and fly directly at our faces. This has led to occasional painful blood loss on the forehead but spectacles have so far protected our eyes.
We protect our ears by using small rubberised ear plugs. Some years ago my son Simon helped to measure sound levels in the colony. He took measurements along transects across the nesting area and recorded levels of up to 107 decibels*. This is far above safety levels recommended by European safety organisations. In the early 2000s I developed tinnitus, followed by loss of sensitivity to some sound frequencies, which led me to fail to hear some higher-pitched bird calls, notably Goldcrests in UK. An audiologist concluded that excessive exposure to Sooty Tern calls was probably responsible for my hearing loss and so we have taken care to protect all who have worked with us since then. I, on the other hand, must now wear hearing aids, except when replaced by ear plugs when in among the birds.
Finally, the rain of droppings calls for a shower after each work session and regular laundry for our work clothing!
*Feare, CJ, Henriette, E & Feare, SEA. 2003. Variation in sound levels within a Sooty Tern colony. Waterbirds 26: 424-428.