I'm very happy to report that the Langstone Harbour Sandwich Tern colony has had a moderately successful breeding season with at least 49 fledglings leaving the Harbour Islands. 122 pairs nested this year meaning that their productivity (a measure of how many fledglings were produced from each nesting pair) is 0.4. Ideally, we'd like productivity to be over 0.75 but given the array of issues they've faced this year, I'm actually very happy with this. Put simply, they've had a hard year but still managed to produce a new generation of youngsters at a time when I often thought they might fail completely.
Above: Getting ready to go, the Langstone Sandwich Tern colony has pulled off something of a miracle this year.
After beginning to settle in early May, a little later that last year, numbers of incubating birds gradually grew until peaking at the middle of the month. As it worked out, the later nesting birds would prove to be the most fortunate this year. Small fish numbers were noticeably low during the early part of the 2016 breeding season with the classic sight of Sandwich Terns with fish in beak being much scarcer than usual. During our first fish survey in the middle of June, the number of fish observed was very low and at this point I was becoming extremely concerned as the small chicks who should have been quite obvious on the shingle ridge were nowhere to be seen. At the same time as this, June was proving to be an exceptionally wet month with often heavy rain on a near daily basis. Seabird chicks and extended rain don't make for a great mix and although their parents are amazingly dedicated to keeping them warm and dry, a soaking wet ball of fluff can find it's temperature dropping to a dangerous level rapidly. When you add to this a surrounding colony of Black-headed and Mediterranean Gulls that would keenly take advantage of a momentarily undefended chick to get an easy meal, you can understand why I feared this year would be a total failure at this point.
Above: A sad post breeding sight and one I expected would be the outcome of this years breeding season en-masse at one point this year.
For reasons unknown, later than expected, small clupids (fish such as Herring) started to become abundant at the end of June although Sandeels were still scarcely seen being bought in. Nevertheless, with fish now being delivered into the colony by adults and the rain having eased off, the much awaited youngsters started to appear from behind their parents in growing numbers.
Above: A healthy young Sandwich Tern emerges from the vegetation.
Quite soon, the lower ridge on the island became a creche of young Sandwich Terns waiting in perfect stillness for their parents to bring food in before suddenly jumping up to call down their fishy meal!
Above: Getting there! Pre-fledged Sandwich Terns awaiting their parents fish delivery on the shingle.
Above: 1,2,3,4,5, these guys eat their fish alive (of course).
Within the last two weeks, we've managed to finish up the final counts and can now say that a minimum of 49 young fledged this year and it's even possible that a few more were successful that we couldn't guarantee we weren't double counting. Phew! Seeing them finally taking their first flights was a big relief after such a worrying start to the year.
Where does that leave them? Well, the colony is still on a good recovery rate from it's low point of just 6 breeding pairs in 2013. Although they didn't have a brilliant year, the fact that they still had success should hopefully continue this momentum. With your help, we'll continue to make sure their undisturbed habitat is ready and waiting for them when they once again return from Africa next spring. The climate and fish availability are a much more difficult question and will continue to be crucial factors in their recovery. On a reserve level, we'll be watching very closely and doing all we can to make sure this amazing seabird graces our sky's in future generations. Have a great winter "Sarnies", we'll see you in spring...