Early winter bird survey - North West Zone December 2019

Just as we pull up in the car to the start of the transect, Tom Forward laments his wish to see a Black Redstart in the UK, after not having seen one for so many years.

Before I even switch off the engine, we spot a small bird bobbing up and down on a concrete wall.
Can I get a whoop whoop Tom...

Juvenile male Black Redstart

A blooming Black Redstart (Phoenicurus ochruros) is our first species of the day!! This really is an exciting find; a red-listed species which was previously recorded as breeding at Gatwick (during my first year here in 2012), however we've had no reports of them for a number of years now.  They are a very scarce bird in the UK, with only around 40 breeding pairs and 400 birds overwintering. 

Tom F. must have been thinking the habitat looked just right for this species, on the urban edge of the airfield. This one seems to be a juvenile male in its first winter plumage; it flies up to perch at the top of the new Boeing hangar. At the end of the survey when we returned to the car, we were even treated to its bizarre scratchy song...

Got to love a good record shot

Our transect begins at the new Boeing Hangar, following the length of the River Mole through the North West Zone. At the old concrete batching works, as well as Black Redstart we pick up another red-listed species; Grey Wagtail (Motacilla cinerea) along with Dunnock (Prunella modularis), which is amber-listed. Like Robins at this time of year and our Black Redstart, the Dunnocks are busily singing away.

It turns out to be a hectic start to the transect, with a Kestrel (Falco tinnunculus), amber-listed, hovering over the scrub and a pair of Stonechat Saxicola rubicola perched up on Teasel seed heads.

Stonechat Saxicola rubicola RSPB

A lone Robin ticks away, but the Wrens Troglodytes troglodytes are sounding off literally everywhere today. 

Wren Troglodytes troglodytes RSPB

The grasslands are good and frosty this morning, with plenty of standing water, so fingers crossed that our wellies are up to the task (normally one or both of us are a bit leaky). A pair of Reed Buntings (Emberiza schoeniclus), amber-listed, can be heard calling from down at the river side.

After picking up a few species along the southern edge of Brockley Wood, we push through the scrub and move down toward the river reed beds. Pausing here just for a moment produces the faithful sound of Water Rail Rallus aquaticus squealing deep within the reeds.

The habitat mosaics here are pretty special. The area has been undergoing natural processes since this section of the River Mole was realigned and designed as a floodplain meadow in 1999. The western edge of Brockley Wood now graduates into mixed scrub habitat and long grass, which in turn blends into shorter grass and the floodplain meadow.

Intersecting habitats result in a high availability of ecological niches, which in turn results in a lot of different species. The only thing missing from these ecosystems are the larger herbivores and other animals which would have managed them, which means that we have to do a degree of the grass and scrub management ourselves.

However, some of the local mammals still leave their mark...

On a small scale, Badgers (Meles meles) can behave rather like Wild Boar. In the picture above, they have been rootling through the turf and soil searching for hidden food (bulbs, invertebrates, mammals nests etc), resulting in local patchy disturbance. This process mixes up the seed bank, allowing for more wildflower diversity and creating important bare ground habitat.

Over to the north of Brockley Wood (likely named for the Badgers), as we poke our heads in a few Wood Pigeon (Columba palumbus) clatter off through the canopy, but otherwise all seems quiet. A lone Nuthatch (Sitta europaea) calls in the distance.

Back down to the floodplain and the mist is still clinging to the banks and reed beds.

Rounding the corner of a reed bed, we are greeted by a flurry of beige-coloured feathers and a pinging sound....

NO WAY. IS that a Bearded Tit?!!!

No record shots today...

I grab hold of Tom F's arm and I'm making tiny Water Rail noises myself... we can't actually believe it, this is such an unexpected find. This is certainly a first for our sites, and after consulting Twitter hive-mind, it might be a first ever record for the Mole Valley district!

Bearded Tit, aka Bearded Reedling Panurus biarmicus RSPB

This is my first ever clear sighting of this species, and even Tom F. hasn't seen one in years. It seems to be a lone male which is likely just stopping off for winter, or may have been pushed out of another more suitable habitat, but what an incredible record and such an affirming tick for the River Mole reed beds. I actually got a bit choked up!

This section of the river is maturing nicely since its realignment, so perhaps we are now starting to see just the right ratios of scrub and reed habitat intermixed with floodplain grassland. It will be exciting to see what else turns up in the next few years.

Pressing on along the floodplain, we are treated to another rare sight; a Water Rail! This is unusual for us as we normally only ever hear them. It flutters across our path, its long legs tucked in but feet protruding out in front as it disappears into the reeds.

Water Rail (Rallus aquaticus) RSPB

As we reach the end of the transect, we are treated to close up views of a Buzzard (Buteo buteo) carrying food in its talons, with two Jackdaws (Corvus monedula) winging their way in lazy pursuit.

39 species is a blooming good number for our winter bird survey sessions. 

This was certainly a memorable one for both myself and Tom F!

	Species	Scientific name
1	Bearded Tit	Panurus biarmicus
2	Black Redstart	Phoenicurus ochruros
3	Blackbird	Turdus merula
4	Blue Tit	Cyanistes caeruleus
5	Bullfinch	Pyrrhula pyrrhula
6	Buzzard	Buteo buteo
7	Carrion Crow	Corvus corone
8	Coot	Fulica atra
9	Dunnock	Prunella modularis
10	Fieldfare	Turdus pilaris
11	Goldcrest	Regulus regulus
12	Goldfinch	Carduelis carduelis
13	Great Spotted Woodpecker	Dendrocopos major
14	Great Tit	Parus major
15	Green Woodpecker	Picus viridis
16	Grey Wagtail	Motacilla cinerea
17	Jackdaw	Coloeus monedula
18	Jay	Garrulus glandarius
19	Kestrel	Falco tinnunculus
20	Long-tailed Tit	Aegithalos caudatus
21	Magpie	Pica pica
22	Mallard	Anas platyrhynchos
23	Meadow Pipit	Anthus pratensis
24	Moorhen	Gallinula chloropus
25	Nuthatch	Sitta europaea
26	Pheasant	Phasianus colchicus
27	Pied Wagtail (yarrellii)	Motacilla alba yarrellii
28	Redwing	Turdus iliacus
29	Reed Bunting	Emberiza schoeniclus
30	Ring-necked Parakeet	Psittacula krameri
31	Robin	Erithacus rubecula
32	Song Thrush	Turdus philomelos
33	Starling	Sturnus vulgaris
34	Stock Dove	Columba oenas
35	Stonechat	Saxicola rubicola
36	Treecreeper	Certhia familiaris
37	Water Rail	Rallus aquaticus
38	Woodpigeon	Columba palumbus
39	Wren	Troglodytes troglodytes

Airport Bryology (Second year survey of mosses and liverworts at Gatwick)

Guest post: Brad Scott (Sussex Botanical Recording Society)

River Mole track, North West Zone

The bryophyte survey of Gatwick started in 2018, focusing on the eastern part of the estate, and this activity has now continued during 2019, exploring the western area, along the River Mole and Brockley Wood. Both parts of the site contain largely similar species, though the character of the two areas is different, and a good number of species were recorded this year which had not been found before.

The corridor of trees, scrub, grass and banks along the River Mole at the north of the site contains a relatively limited flora. Grass and scrub contain the common species Brachythecium rutabulum, Calliergonella cuspidata and Kindbergia praelonga, and common epiphytes are found throughout the area. Willow is a particularly rich host for epiphytic bryophytes, and consequently on the trees along the river can be found Cryphaea heteromalla, Metzgeria furcata, Metzgeria violacea, Orthotrichum affine, O. diaphanum, O. lyellii, O. pulchellum, Radula complanata, Syntrichia laevipila,  S. latifolia and Ulota phyllantha, some in good quantity. On the river banks and other frequently inundated areas can be found Platyhypnidium riparioides.

Syntrichia latifolia

Path edges and soil are often colonised by small acrocarpous bryophyte species, which include Barbula unguiculata, Dicranella staphylina, various Didymodon species and Pseudocrossidium hornschuchianum, and the liverwort Lunularia cruciata. Many of these are part of a dynamic flora, changing over the years as larger species move in. This means that some transient taxa can be found, the most significant being the small frilly-leaved liverwort Fossombronia caespitiformis, which is a rare colonist with a Mediterranean-Atlantic distribution. A more common species in this genus was found in 2015 in the eastern part of the Gatwick estate; these can only be determined with fertile plants, with capsules present, so that the decoration of the spores can be examined. It sounds harder than it is. Fossombronia caespitiformis was found with Weissia controversa var. controversa on an otherwise bare bank about 10m back from the river.

F. caespitiformis spore

The middle section of the river comprises slightly richer wooded habitats, including species such as Atrichum undulatum, Eurhynchium striatum and Mnium hornum. Some additional epiphytes were also found, such as the tiny liverwort Cololejeunea minutissima (often, but not always, on Ash), Orthotrichum stramineum and Zygodon viridissimus, with its distinctive longitudinally septate gemmae. Brachythecium albicans can be found on various sandy banks, and a number of other common species associated with buildings, concrete and similar substrates occur.

River Mole at high flow

The southern-most section has a slightly different character, with occasional patches of the large scented liverwort Conocephalum conicum above the water by the river, and the moss Oxyrrhynchium speciosum in among the wet, scrubby area west of Larkins Lane; this is rare in the south-east, and I had to compare my sample with some material collected a few years ago in Cambridgeshire on a meeting of British Bryological Society. Additional epiphytes were recorded along the river and in Brockley Wood, such as Syntrichia papillosa, Ulota crispa and Zygodon conoideus, and large areas of drainage and boundary banks near Horley Road were often abundantly covered with the scarce moss Epipterygium tozeri. This species has a world distribution which is mainly of xerophilous Mediterranean communities. In the UK it is at the edge of its range, and is mostly known from Devon, Cornwall and south-west Wales, with scattered records in other southern counties.

Epipterygium tozeri leaf

E. tozeri

Ditch habitat within River Mole woodlands

This second survey has turned up a number of fairly common species which were not recorded in 2018, plus a few rarer ones, bringing the total to 96 taxa, which is a very good number for a low Weald site. Some of these may have been overlooked, while others either have little suitable habitat across Gatwick as a whole, or within LERL. The river, with its frequent willows, provides good habitat for a wide range of epiphytes, as well as several species that occur on the edge of flowing freshwater habitats. Disturbed soil often hosts many early colonising species, and the various groundwork and other activities provides considerable opportunity for many different bryophytes to thrive. Most of the site is neutral to basic, as evidenced by the species present, but some areas contain more calcifugous species.

River Mole at medium flow

Continuing attention to the site in the coming years may well reveal additional species, and the slowly-changing flora may be profitably monitored as the years go by, as new groundwork is undertaken, and the recent landscaping settles and matures.