The Terns of Kubbar Island

Week 24, 16 June 2012 - Kubbar Island (Click on images to enlarge)

This was to be our last family outing with Graham Whitehead joining us, before our long-awaited summer holiday and we couldnt have wished for a better day in terms of weather and sea conditions. Actually I have difficulty calling it a sea when the water was so flat, calm and mirror like, especially when compared to the pelagic trips off Cape Town.

Summer is peak time for 4 species of Tern that breed on this tiny sand island that has suitable habitat for each of the 4 species. Unfortunately, this is also a very popular destination for boats and jet-skis and creates a lot of additional pressure for these birds due to uneccessary human disturbance. Since there are no natural predators on the island, I believe most fatalities of young are due to over-exposure from the harsh summer temperatures.

Normally the first species you see on approach to the Island are Bridled Terns and it doesnt take long for them to use the boat as a perch to get higher above the ground and water for slightly cooler air.

Bridled Tern (Onychoprion anaethetus)

We swam to shore and encountered some White-cheeked Terns with recently fledged chicks already down at the waters edge where the lower temp at the shore line helps these very young birds to better regulate their core temperatures (my theory anyway). But this is also where the most disturbance occurs with so many people on the beach - the adults continuously having to fly off, leaving the young exposed - sometimes for too long.

White-cheeked Tern with recently fledged chick on the beach (Sterna repressa)

Many White-cheeked Terns were still on their bare nests with both eggs and young away from the sea. I am amazed everytime I see this spectacle that the adult birds sit on the eggs without any protection whatsoever from the elements and successfully raise their young.

White-cheeked Tern with recently fledged chick and egg (Sterna repressa)

In a different area of the island, the Lesser-crested and Swift Terns have a chaotic (it seems) communal nest site with eggs and young appearing to be haphazardly distributed.

Lesser-crested Tern colony - organised chaos (Sterna bengalensis)

Lesser-crested Tern on eggs (Sterna bengalensis)



Lesser-crested Tern with young - whose is whose? (Sterna bengalensis)

Interesting that the much larger Swift Terns (though much fewer in numbers) choose to nest with the Lesser-crested.

Swift Terns in Lesser-crested colony, or is it the other way around? (Sterna bergii)

Swift Tern (Sterna bergii)

Whilst sitting on the beach, we watched with interest how the Bridled and White-cheeked Terns would leave their nests (with eggs and young) and wet their belly feathers in the sea. Again, I assume this is to provide some coolness to assist with better regulating the temperature for eggs and young.

Bridled Tern wetting the belly feathers (Onychoprion anaethetus)

White-cheeked Tern doing the same, sometimes almost comical (Sterna repressa)

Whilst swimming we had an influx of Jellyfish (not sure which species) and saw a small school of Garfish from the boat.

One of many Jellyfish

Jellyfish in the shallows

Stranded on the beach, well not quite - my son put it back

Garfish

Again, I was reminded how selfish some people are when you see the absolute mess that is left behind after spending a day on what could be a pristine beach on this small island, as well as an absolute disregard for the breeding birds by some individuals. This highlights the need for awareness that this important little island is for breeding birds (and only for 8-weeks of the summer) as well as people and it is up to us to respect our environment and to be responsible to clean up after ourselves. If visitors have packed their picnics and bbq's to take to the island from the mainland, how hard is it to take the same stuff back with you - really?

Uneccessary disturbance with a stick of the breeding Bridled Terns

Take only pictures - leave only footprints - dont we all wish for that!

More mess on what could be a pristine beach

More awareness and a Management Plan would ensure that birds and people could both enjoy this island, in the short breeding season