With the first egg seen on the tern raft on Saturday 15th June hopes are high for a successful breeding performance. However, with only one pair on the raft at the moment the lone egg is vulnerable to predation as terns usually rely on all the adults in a colony being able to mob intruders and protect the eggs. It remains to be seen if the policy of laying early will work.
The terns were a few weeks late in arriving this year and it raises doubts about whether they have time to raise their young before they have to leave for Africa. It takes about three weeks of incubation before the eggs hatch and a further three to four weeks before the young are able to fly. This means that hatching should occur from the 6th July onwards and fledging from 27th July onwards.
Any eggs laid as late as 20th July will still have a chance of being successful, as long as the colony is still active all through August.
So will they be ready for migration? The answer is yes. While some birds will start to leave as early as July, the bulk of them will leave the Basin in late August and September but they move south quite slowly and some birds are still in the UK in October.
It is interesting to note that Common terns from the UK migrate to the West African coast in winter and fly a bit further south than our Ospreys do and can be found in Ghana and Senegal.
For live streaming of the Tern Raft camera just click on the following link http://scottishwildlifetrust.org.uk/things-to-do/wildlife-webcams/montrose-basin/#