The weather finally
took a turn for the better on Havergate this week after what seemed
like almost daily thunder showers, lightning strikes, torrential
downpours and a nagging wind.
Now as the season
starts to enter its final lap we can start to make some early
estimates on how things have gone.
There are quite
literally hordes of large gull chicks on the island. Ranging from
small to almost fledgling. It seems the low levels of disturbance
and lack of predation is to the gulls liking and despite nestingnumbers falling away slightly on the island they continue to do
extremely well in terms of producing young. In the next couple of
weeks we will do the chick counts and from there we will be able to
establish a productivity figure.
Things are not quite as
rosy for the Greater black backs where the pair in main lagoon either
failed or where predated at an early stage. The pair in Doveys held
territory but it is unclear whether they bred or not.
Common gulls; it is
possible that some are hiding in the gorse and I am unable to see
them but it seems that common gulls will not do as well this year as
they did the year before. There are currently 3 big chicks spending
their time loafing on the saltmarsh whilst the rest of the colony is
worryingly quiet. There can be no doubts that predation pressure
will have had an effect on some of the chicks. However, the gorse
should offer a natural protection against the gulls, there appears to
be a food issue for the adults to contend with, a couple of biggish
chicks (well over a week old) have been found dead within the gorse.
The best strategy appears to nest in gorse and after 10 days or so
take the chicks down to the salt marsh and essentially let them feed
themselves on invertebrates and scavenge the shoreline.
Common terns; optimism
was extremely high last week but as large gull predation pressure has
stepped up there has been a noticeable decline in the number of
chicks. As an estimate I would say a half of all chicks have gone in
the last week. One would expect a decline in the number of chicks at
about this time as 2nd and 3rd hatchings die
off unless its an exceptional year for sandeels. However, losses have
been much higher than can be accounted for just by this. However,
there are least 7 or 8 big chicks on the lagoon who may in fact be at
the stage where they can expect not to be taken by gulls.
Avocets did eventually
breed on the island but only in low numbers (3), one pair abandoned,
one pair failed (presumed predated) and the final pair is still sat
on eggs. Oystercatchers have fledged one chick at least, which is
something of a red letter day for this species on Havergate it has
been many years since this species recorded any success.
The big summering flock
of Spoonbills have yet to arrive but waders are starting to pass
through with numbers of redshanks and Lapwings beginning to build up.
mid June the results of the breeding season start to come in,
although how successful it proves to have been in terms of chick
production will have to wait for next month.
with the good news Common Terns continue to strengthen there foothold
on the island with the colony increasing from 29 pairs in 2010 to 35
pairs this year. For those not familiar with the story of the terns
on Havergate they reached a nadir in 2009 when only 2 pairs nested
across the island. This situation was only ameliorated by a stroke of
luck last year when inexplicably 29 birds arrived extremely late
(early July) and proceeded to breed with a degree of success. These
successful birds have made up the bulk of our returning colony this
Common Tern chick
gulls continue to breed in good numbers and help Havergate maintain
its position as the largest common gull colony in the south east of
England. This species was up by 1 on last year from 18 to 19. The
largest the colony has been since 2008 and nudging us ever closer to
our management plan total.
doesn’t really feel like good news when one considers the history
of the island but avocets continue to have a foothold on the island
with 3 pairs nesting in and around the tern colony this year. In all
reality these birds are likely to be failed breeders from other sites
who are having one last throw of the dice this season. Whilst this is
down on last year and continues the trend of avocets becoming an ever
scarcer breeding bird on the island. For a long time it looked like
we would have no avocets for the first time in a long time, so lets
celebrate what we do have.
the bad news, though much depends on your attitudes towards large
gulls but both lesser black backed gulls and herring gulls have
declined this year.
lesser black backed gulls have dipped below a thousand breeding pairs
(991) for the first time since 2007.
their huge increase from 330 to 550 pairs in one year herring gulls
have settled down to 492 pairs across the island. This means that the
complete large gull population (both lesser and herring gulls) has
declined overall for the first time since 2009.
Jane and Geoffrey surveying the gulls
decline in both species specially the lesser’s is likely to reflect
national trends, herring gulls the picture is not quite so clear as
it bouncing around all over the place and has been for the last three
years. What does seem likely, though perhaps I shall be proven wrong
next year is that the era of the exponential growth in the large gull
population is over.
have declined to an all time low of 16 pairs nesting. Years of gull
predation is likely to be driving the population down and Mallards,
Shovelers and Tufted Ducks maintain little more than a toehold on the
island. What is perhaps more surprising though is that Canada geese
have declined by 8 pairs and are down to 44. Though we have had the
bonus of prospecting swallows and singing whitethroats this year, along with red legged partridges, pheasents and a pair of moorhens
wraps up the breeding season surveys. Most species are feeding
chicks of various sizes some of the large gull chicks are big to
small tern chicks which are just starting to hatch. The wet weather is
a concern as this is not ideal weather for young chicks, a lot will
now depend on the attentiveness of the parents and predation is
always an issue.