Common tern numbers at the Oysterbeds have increased to c96 apparent nesting birds; c34 on the inside of the ‘curved’ island while on the straight island there are c56 visible on the north side and 6 on the south side. Like 2013, the common tern season could extend well into August or even September.
At least one Mediterranean gull youngster is now able to get airborne. After a very short flight, it spent some time paddling about (closely accompanied by a parent) amongst the many black-headed youngsters in the lagoon. A few failed pairs of Mediterranean gulls are demonstrating their ‘nuisance’ traits. As observed many times previously on the harbour islands, it seems that after a failure at the egg or chick stage, their pair-bonding remains very strong; hence, the noisy calling as they fly over and their half-hearted territorial behaviour. They often develop a taste for eggs or small chicks (of any gull, tern or wader species) and these failed birds seem to prioritise the harassment of successful broods of other Med gulls (as has happened at the Oysterbeds’ site recently). Hopefully, such birds will soon move on out of the area; otherwise, the multitude of common terns might have a very unproductive year!
Black-headed gulls are continuing to have a very successful breeding season, with several broods of three at the flight stage. There are often ‘crèches’ on the lagoon shores or on the lagoon itself where the youngsters are developing their foraging, flying, bathing and (of course!) territorial-behaviour skills. All of them are relying primarily on their parents for food but many of the oldest broods are flying further afield accompanied by parent birds. A youngster was seen ‘foot-stamping’ for prey items in a pool on the mudflats; was that learned or in-built behaviour?!
There is still an ‘active’ oystercatcher nest east of peg B on the north side of the straight island. Another pair now seem to be apparently on nest east of peg H on the straight island; but, in the typical oystercatcher fashion, there are periods when the nest site has been unattended by either bird.
Locally, It is continuing to be a good season for many floral species (e.g. Lady’s bedstraw, Tufted vetch, Meadow vetchling, Pale flax etc), which is good news for many invertebrates. There are many Marbled White and Meadow Brown butterflies (most of which have been instructed by their agents to not to pose for photographers!). However, Common Blue butterflies are presently a rare sight in the locale (Holly Blues are more numerous); this could be a result of the very wet winter, or, perhaps, a localised phenomenon caused by the winter’s surging tides and storm driven ‘sea spray’. It will be interesting to hear reports from other locations.
PS Great news; Wez Smith, the RSPB Site Manager, reports that there are good numbers of little tern chicks on the harbour islands and some should be fledging soon.