Arctic Skua? kittiwake?
All good guesses
but since the year 2000 the two fastest declining seabirds are the
much less heralded herring gull and lesser black backed gulls.
This is according to
the SMP (seabird monitoring programme) data recently released by the
JNCC. This is a ongoing annual monitoring programme of all 26
breeding seabirds in the UK that allows broad trends to be
established and monitoring programmes to be implemented at a
Since the year 2000 the
herring gull population in the United Kingdom has declined by 38% and
lesser black backs have declined by some 36% since the year 2000. So,
don't let the massive 943% increase in herring gulls nesting in
cities in towns fool you, this is a bird in decline. What does this
mean in real numbers? Well, both species had approximately 110,000
pairs in the year 2000 this is now reduced to just over 70,000
Just in case you where
wondering Arctic Skua's have declined by 34%, Kittiwakes have
declined by 30% and Little terns have actually increased by 7%.
Obviously whilst the
decline of both large species of gulls is a concern they do have one
advantage both still have robust populations numbering well over
70,000 pairs in the British isles, unlike some other seabirds which
are declining from a much smaller population base. A classic example
is arctic skua's which only have around 1,500 apparently occupied
territories after the recent decline.
I think I may have
discussed this before but several theories exist as to the reasons
for the nationwide decline. Ranging from mammalian predation to
disturbance on the breeding colonies, no doubts these are having an
impact. Likely it is these factors that are pushing herring gulls
into urban areas, that and food is abundant.
The other theory is
that both the species are returning to a natural level, previously
both species have have had access to plentiful indeed virtually
limitless food in the winter by utilising uncovered rubbish tips,
specially when one considers the changing ecology of lesser black
backed gulls which now no longer migrate to southern europe and
northern africa in the winter. These days are coming to an end as
governmental policy is to cover up rubbish tips, this may be
increasing winter mortality rates of both species of gulls and also
reducing the ability of adults to gain proper breeding body
conditions. Other species are know to have much less productive
breeding year if there body condition is lower.
To a certain extent
only time will tell for both these species, sadly neither species
have been particularity well monitored in the past which makes
drawing conclusions subjective and at worst borderline guesswork.
Island wise, the summer
is on us now. The first large gull chicks hatched on May the 17th,
the exact same date as last year. Common gull nests are now in double
figures, common terns are still showing an interest in Cottage flood.
Sadly, it looks like for the first time in half a century avocets
will not breed on Havergate island but both pairs of greater black
backs (Suffolks only pairs) are both back and on eggs.