The problem with Scandinavian Rock Pipit in winter is that
many individuals are inseparable from our nominate Anthus petrosus petrosus (subsequently
referred to as ‘petrosus’). That has led to several county and regional bird reports being a bit reluctant to document Anthus petrosus littoralis unless this
relates to individuals (usually in spring) which show a subtle combination of
characters which suggest they are not petrosus
(e.g. well-defined supercilium, ‘cleaner’ more individual breast streaking
and noticeable white (not muddy white) outer tail feathers, with the more
clear-cut individuals superficially resembling Water Pipit)
It has been increasingly apparent in this country that
there is a quite specific outer saltmarsh habitat which does not 'proximately overlap'
with rocky coasts and shorelines which has its own wintering population of Rock
Pipits. The problem with this habitat is
that at many sites the birds are 'impossible' to watch closely and document
unless there are high spring tides forcing them to the inner end of the
saltmarsh within observational range.
Therefore opportunities to study them can be limited to just two or
three tides per winter period month.
This is because they feed in the outer saltmarsh creeks and are very
reluctant to leave this area unless the adjoining saltmarsh is completely
inundated by the tide. Birders also tend
to ‘ignore’ them as they search for the occasional Water Pipit (or hope for a
long-shot Buff-bellied Pipit) during these limited opportunities.
Here is an extract from the Christchurch Harbour
Ornithological Group website: "The
location of winter pipits within the recording area can be used as an indicator
as to the likely species or race. Rock Pipit seen on the Hengistbury shoreline
or Stanpit river bank are almost exclusively Western European petrosus birds,
some of which are thought to be resident and form the Hengistbury breeding
population. However, Rock Pipit
encountered on the saline marshes of Stanpit are candidates for littoralis race.
Of course, many are simply
indistinguishable from petrosus , but there are often individuals that
stand out from the crowd". See
also: http://www.manchesterbirding.com/logicalityoflittoralisiddocmanchesterbirding.com.pdf
for a closer look at the problem of field identification
In north Germany, for example, there are no breeding (or
wintering) petrosus Rock Pipit and
the species is exclusively of the form littoralis
and a denizen of the muddy outer saltmarsh creeks. Here it feeds on e.g. hydrobia which is, of course, an abundant food source in our own outer
saltmarsh creeks and utilised by e.g. Redshank and Shelduck (ref: Dierschke and
Bairlein: Habitat selection of wintering passerines in saltmarshes)
Here in Lancashire/Morecambe Bay, with one small
exception, we do not have resident 'rocky coast pipits' breeding nearby. Apart from an isolated pair in at least 2015
on Chapel Island in the Leven Estuary,
the nearest breeding birds are St Bees in Cumbria and North Wales. The migration Atlas, utilising ringing data,
also deems petrosus as 'mainly sedentary',
whilst conversely the Scandinavian form is known to be migratory. However, we do receive the occasional 'dark
smudgy-breasted individuals with 'no' supercilium' at rocky sites such as
Heysham Harbour with two cases of late spring birds holding temporary territory
around Heysham Head/Harbour, including "a few" observations of parachute flight. It is presumed that these might be wandering
petrosus, but we have no ringing
evidence, just a combination of habitat and temporary territorial behaviour
However, by far and away the preferred habitat for Rock
Pipit in Lancashire is exactly that of known littoralis in Germany; outer saltmarsh creeks. We have already had confirmation of this
with two previous sightings of Scandinavian birds - one fully documented, the
other not narrowed down to an individual.
Now we have a third, but unlike the two previous ones, this was
well-photographed.
As can be seen from the photograph of this latest
colour-ringed bird, there is little or nothing to suggest that it is any
different from our resident petrosus,
but, in Lancashire, as in many other coastal counties, it is surely time to
assume all the saltmarsh Rock Pipits are littoralis
by virtue of clear-cut habitat preference (beware the occasional Water
Pipit). This should be reflected in
county and regional bird reports and indeed, in a county such as Lancashire,
maybe the ones deserving individual documentation are the occasional rocky
habitat individuals suggesting dispersing petrosus! Caution is obviously needed with birds on
passage e.g. small numbers of presumed littoralis
pass through Heysham on especially autumn passage and documentation of littoralis should be limited to winter
residents flushed out during saltmarsh inundation
Thanks to Chris Batty (photo supplier)
and Andrew Cornall for persevering with this bird, leading to documentation and
the Lancaster RSPB group for first drawing attention to it
Ring no:Stavanger 8E28835
Yellow colour ring HJP (Left tarsus metal ring. Right tarsus
yellow ring with three black letters HJP engraved).
Age/sex:: Adult female (hatched 2013 or
before).
Biometrics: Wing 83 mm. Weight: 19,8 g.
Ringing date: 22.08.2013, 0900 hrs.
Ringing place: Makkevika (62*30'N-006*02'E)
Giske, Giske, Møre &Romsdal, Norway.
Remarks: Caught in walk-in-trap at our
wader station (Giske Ornithological Station).
Ringer: Sunnmøre Ringing Group.
Finding date: 09.02-12.02.2016, almost certainly
the bird seen in January
Observed: Pilling Marsh (53*56'N-002*53'W)
Lancashire, England / UK.
Remarks: Photo-documented
Observers: Andrew Cornall and Chris Batty
Distance:1084 SSW.
Further information
Colour-ringing in Norway:
Sunnmøre Ringing Group hope that you
will look for flagged Common
Ringed Plover (Charadrius hiaticula),
Common Sandpiper(Actitis hypoleuca), Grey Plover (Pluvialis squatarola)and Curlew Sandpiper (Calidris ferruginea). All these species have metal ring on left
tarsus, red colour ring on left tibia and yellow flag on right tibia engraved
with 3 black letters.
Pete Marsh
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