Turn and tern again?!

At Pitsford Water nature reserve, we are fortunate to have six tern rafts which instantly attracted a breeding colony of terns to the reservoir back in 2000 when the first raft was installed, writes Isabella Clarke, one of our Northants Volunteer Officers

Terns are beautiful, graceful birds with their slender profile and swallow-like tails, and they make an epic journey to be back here to Pitsford Water, Northamptonshire for the breeding season.

The chicks from the rafts are ringed by licenced bird ringers and this produces vital information for scientific research into bird conservation.  It also produces some interesting insights into their lives.  One bird that was ringed as a chick at Pitsford was caught again some time later by a ringer in Namibia - our furthest movement recorded so far. Most British hatched common terns winter off the coast of West Africa so our one in southern Africa was unusual.  Scandinavian common terns regularly migrate to the southern African coast, but one Swedish bird was found on the coast of West Australia following storms in the Indian and Southern Ocean! That’s about 10,000 miles!  

Common tern chicks by Lynne Barnet - taken in 2022

Common tern chicks, Credit: Lynne Barnet

This kind of information is both fascinating and useful – so, over the past two decades, we and the terns made the most of the rafts.

However, life is full of uncertainty and this year we saw that all the tern rafts had been occupied by breeding black-headed gulls. The gulls are residents in the UK, which meant they were able to nab these convenient breeding places before the Terns had made their long journey from their winter feeding areas along the coast of Africa.

We were delighted to have a new breeding population on site, of course, and the gulls certainly made themselves at home. One of the rafts, for example, was a manic baby-gull playground with well over 30 of them crying up to their parents for food!

Common tern by Neil McMahon

Common tern, Credit: Neil McMahon

But that presented a problem for the terns and so for us. What would the terns do?

Here’s where some good fortune came in – thanks to the generosity of our local nature lovers! We were a recipient of Waitrose Kingsthorpe’s Local Charity donation and with the money were able to source another raft, prepare it and tow it out into Walgrave Bay – the original six tern rafts (or perhaps we should now call them ‘black-headed gull rafts’) are in Scaldwell Bay.

It was a race against time, but the very day that we launched the new tern raft, Terns checked it out and decided it would do. Phew! We are so grateful to Waitrose Kingsthorpe for their generosity.

About 20 pairs nested on the raft, which is covered in gravel, their preferred surface. The eggs are perfectly camouflaged – you have to look very carefully to see them. The birds themselves have no problem though – each pair knows precisely which nest is theirs and, when the chicks have hatched, they feed their own young. However alike they look to us, those fluffy chicks and, later, fledglings are unique as far as their parents are concerned.

Common Tern eggs

Common Tern eggs

It’s great that we have been able to provide a raft for the terns as they are loyal to their breeding sites and we want to keep seeing these beautiful birds performing their swooping aeronautical displays over the reservoir for many years to come.

We have already sourced another raft and will buy or build as many rafts as resources allow over the next year to establish a thriving tern colony for next year– away from the black-headed gull colony.

Black Headed Gull by Neil McMahon

Black Headed Gull, Credit: Neil McMahon

Did you know?

  • Common terns were first recorded in England in Anglo-Saxon times.
  • They live, on average, for 12 years – but the oldest recorded individual lived until he or she was 33!  Pitsford’s oldest known chick lived to be 19.
  • In Britain, they are also known as sea swallows, darrs and tirricks.
  • Common terns who were ringed in the UK have been found all over Africa and even in Australia!

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