|Juvenile Purple Heron Otmoor RSPB courtesy of Ewan Urquhart|
So August has come and gone and with the departure of summer naturally a birder's thoughts start turning to autumn vagrants. Actually of course, August is firmly in the autumn camp as far as birding is concerned and this month proved to be a good one with at last some decent birds coming our way after what has frankly been a very poor first half of the year. By far the star bird was a juvenile Purple Heron that was found on the 7th by visiting birders from Windsor and which remained on the reserve until the end of the month. This species is of course notoriously difficult to see with flight views often the only way of seeing it and generally this one proved no exception. To start with it seemed to fly about quite a lot enabling lots of keen county and out-of-county birders to tick it as it relocated from one part of the reserve to another. As time passed it seemed to get to know its way around the area more, needing fewer flights as it became increasingly difficult to catch up with. This is the first bird in the county since 2007 when a juvenile bird was seen on the 11th of August at the Pinkhill reserve adjacent to Farmoor reservoir before relocating to the Otmoor RSPB reserve.
Below is an extract from the superb 'Birds of Oxfordshire' by J.W Brucker, A.G.Gosler and A.R Heryet (Pisces Publications 1992) which gives an indication of the history of this rare species within the county.
'This very rare vagrant was recorded twice in the nineteenth century and seven times in the first 90 years of the twentieth century. One was shot at Aynho in May 1928 as it left the Cherwell valley. In the long, cold winter of 1963 one joined a party of Grey Herons at Appleford Gravel Pits from the 17th-20th of February. An adult at Wroxton from the 22nd of May to the 1st of June 1971 was among several which wandered into Britain in the early 1970s. Other records in the 1970s were of an immature in the Cherwell Valley in August 1976, a sub-adult at Marston on the 14th of May 1979, and one at Bicester on the 5th July 1979. The last sighting was of one over the scrape at Stanton Harcourt Gravel Pit on 22nd of August 1981.'
|Juvenile Purple Heron Otmoor RSPB courtesy of Terry Sherlock|
The next headliner was a juvenile White-winged Black Tern which arrived at Farmoor Reservoir on the 27th with thirteen Black Terns. The group was present over F2 from approximately 4pm until 7pm before they all headed off South West.
|Juvenile White-winged Black Tern Farmoor Reservoir|
Above & below courtesy of Terry Sherlock.
White-winged Black Tern (juv) please view at 1080p HD
This juvenile was at the dark end of the plumage spectrum and caused some consternation due to the presence of a dark peg on the birds shoulders a feature usually seen as diagnostic in juvenile Black Terns. It constitutes the tenth record for Oxfordshire following a juvenile at Farmoor reservoir from 5th-14th of September in 2011. All of the previous records are of immature birds with the exception of a summer plumaged adult on the 2nd May 1971 at Farmoor Reservoir.
|Juvenile White-winged Black Tern courtesy of Terry Sherlock|
There have been two Great White Egrets at Pit 60 this month. The juvenile that arrived in July remained until at least the 13th and what was probably the same bird was seen briefly at Farmoor reservoir on the morning of the 6th. A second bird, this time an adult, then arrived at Pit 60 on the 29th and remained until the end of the month. There is clearly something about Pit 60 which is very attractive to this species!
|Juvenile Great White Egret at Pit 60|
|Adult Great White Egret Pit 60 courtesy of Badger|
On to "good county birds" now and we had a pair of rare Grebes this month, both at Farmoor as you'd expect. A juvenile Red-necked Grebe turned up at the reservoir on the 26th and stayed until the end of the month. We've rather been spoilt over the last few years by the regular appearance of an adult bird which has taken to stopping of at Farmoor on both legs of its migration but this juvenile is clearly a different bird. Let's hope that it too becomes a regular. The other rare Grebe was a Black-necked Grebe which turned up on the 29th and also chose to linger at least until the end of the month.
|Black-necked Grebe courtesy of Richard Tyler|
|Red-necked Grebe Farmoor Reservoir courtesy of Mark Chivers|
|Red-necked Grebe courtesy of John Reynolds|
A fine Osprey was a great discovery on the 7th over the Upper Cherwell Valley although unfortunately it did not stop. The Otmoor family of Marsh Harriers, including the one juvenile, remained throughout the month on the reserve.
|Osprey Upper Cherwell Valley courtesy of Colin Wilkinson|
The Eight Mandarin Ducks that showed up at Otmoor at the start of August remained throughout the month. A Shelduck was seen sporadically on Otmoor over the month as was an unseasonal Wigeon which seen from at least the 6th. It was a good month for Common Scoters with birds seen on the 10th-11th and on the 27th-28th at Farmoor reservoir. At least three Bitterns were being seen frequently over the reedbeds on Otmoor (see the News section below). The pair of Common Cranes remained at Otmoor RSPB until the 15th when they were seen flying off high to the South West, presumably to winter on the levels.
|Common Scoter Farmoor Reservoir courtesy of The Gun-slinger|
Gulls & Terns
The third summer Caspian Gull from last month continued to show at the Farmoor roost until at least the 5th. Yellow-legged Gulls numbers peaked during August with good numbers utilizing Farmoor reservoir for roosting. Birds were also seen at Grimsbury with three occurring at the Banbury reservoir on the 10th. Mediterranean Gulls started arriving back in the county with an adult at Grimsbury reservoir on the 10th, a juvenile there on the 12th-13th and at least one juvenile was seen at Farmoor on the 27th.
|Adult Mediterranean Gull Grimsbury Reservoir courtesy of Mike Pollard|
|Juvenile Mediterranean Gull Farmoor Reservoir courtesy of Badger|
An early Little Tern was a surprising find at Farmoor reservoir on the 9th and would kickstart what would turn out to be a great month for Terns at the Oxford reservoir. The arrival of fifteen Sandwich Terns at Farmoor reservoir on the morning of the 24th was a shock as was their protracted stay affording a great opportunity to catch up with these superb sea swallows before they continued their southern migration.
Twenty Black Terns spent the day at Farmoor Reservoir on the 19th before drifting off to the West in the evening. The 19th also saw three Arctic Terns as well as approximately ninety Common Terns at
the Oxford reservoir. Thirteen Black Terns were also at Farmoor on the 27th along with the juvenile White-winged Black Tern. Single Black Terns were at both Grimsbury and Farmoor reservoirs on the 31st.
The first of two juvenile Little Stints arrived at Farmoor Res on the 16th, joined by the second bird on the 17th with both remaining until the 22nd.
|The first of two juvenile Little Stints Farmoor Reservoir courtesy of Richard Tyler|
|Both Little Stints at Farmoor Reservoir courtesy of Peter Law|
Wood Sandpipers was seen from the first screen at Otmoor on the 3rd and in flight over Shrike Meadow Farmoor on the 5th. Fifteen Green Sandpiper at the Bicester Wetlands Reserve on the 13th remained the highest count within the county this month with Common Sandpiper numbers peaking at nine birds at Farmoor reservoir by the 26th. Two juvenile Black-tailed Godwits stopped off at Grimsbury reservoir on the 8th with twelve birds seen at Farmoor over the course of the 21st. Single birds were seen on Otmoor from the 22nd-25th, at Rushey Common on the 23rd and at Farmoor on the 27th.
|Black-tailed Godwits Farmoor Reservoir courtesy of Andy Last|
two present on the 23rd and again on the 28th.
|Turnstone Farmoor Reservoir courtesy of Dai|
An impressive twenty two Ringed Plover that flew over Farmoor Reservoir on the 21st unsurprisingly remained the highest count for August. Sanderling were patrolling the causeway at Farmoor on the 16th and the 21st. It was a good month for Greenshank with three at Farmoor on the 15th, four on Otmoor on the 17th with this number increasing to six birds by the 18th. At least three birds were present at Standlakes Pit 60 from mid month with singles at the Bicester Wetlands Reserve also on the 15th.
|Greenshank Pit 60 courtesy of Steve Burch|
Whimbrel were also on the move with four seen over Farmoor Reservoir on the 12th, two birds over Lollingdon Hill on the 17th singles seen near Grimsbury reservoir on the 10th and again at Farmoor on the 24th.
A few sub-species to get to grips with to start with. A possible candidate for a scandinavian Willow Warbler P. trochilus acredula was seen at Lark Hill on the 28th. Amongst the many Northern Wheatears on passage through our county this month was a stunning juvenile male Greenland Wheatear O. oenanthe leucorhoa - although only a subspecies, its a bit of a looker! It was found at Farmoor on the morning of the 24th but unfortunately this long distance migrant didn't stop for long. A female Blue-headed Wagtail M. flava flava was a great find amongst the commoner Yellow Wagtails M. flava flavissima on Port Meadow from the 27th-28th.
|Wheatear of the Greenland race Farmoor courtesy of Jim Hutchins|
A Tree Pipit briefly settled at Banburys Grimsbury Reservoir on the 25th which was a great record of what has now become a difficult bird to see in Oxfordshire. Also within the category of "increasingly difficult to see in the county" were the two Turtle Doves at Otmoor RSPB which remained throughout the month. A single bird was also noted again within the Ministry of Defence compound near Arncott.
|Tree Pipit Grimsbury Reservoir courtesy of John Friendship-Taylor|
Redstarts were well represented this month with increasing numbers within Otmoor's Long Meadow,
reaching an incredible thirteen on the 10th and an outstanding nineteen birds on the 16th. Two birds seen at Harwell on the 2nd with several birds being seen at Lollingdon Hill near Cholsey throughout the month including three on the 11th and five birds in the vicinity on the 26th. Four birds were also seen at Letcombe Bassett on the 16th, with two birds at Stonesfield Common on the 23rd. Singles were at the Balscote Quarry reserve on the 5th, Lark Hill on the 7th-9th, Port Meadow on the 21st, at Farmoor reservoir on the 29th and at Aston Rowant NNR on the 30th. Two birds were again at Lark Hill on the 28th-30th with a pair in the south of the county near Padworth on the 29th.
|Male Redstart Otmoor courtesy of Ewan|
Whinchat were being seen on Otmoor from the 8th including three birds at the Pill on the 13th and three on Ashgrave on the 30th. Four Whinchat were seen at the Upper Cherwell Valley site near Banbury on the 29th. Two birds were at Farmoor on the 18th and at Stonesfield Common on the 23rd with singles seen at Lark Hill on the 9th, near Blewbury at Lollingdon Hill on the 11th with two present at the latter site on the 16th and three present on the 26th.
|Whinchat Farmoor Reservoir courtesy of Andy Last|
|Young Cuckoo Otmoor RSPB courtesy of Andy Last|
The Art of Birds
This month Paul Thomlinson has once again turned his attention to the RSPB Otmoor reserve and has created a stylised sketch of the the fabulous Purple Heron.
'I misjudged the purple a bit, so it's more purple than the juvenile on Otmoor, but hey, artistic licence etc'
Bitterns return to breed on Otmoor.
|Courtesy of Cliff Grove|
Bitterns on Otmoor
by Peter Barker
by Peter Barker
A reedbed is a very secret place, like an expert poker player it is inscrutable, it keeps its cards close to its chest and is reluctant to give up its secrets. It can really only be looked at from the outside, to see, know and understand what is going on inside it is very difficult. It is not like a wood that you can stroll into and count trees, find nests and survey what is going on. Inside a reedbed there are no paths, just meandering channels, there are few landmarks and one patch of reeds looks exactly like another. What we can understand and know about comes down to patient observation, deduction, speculation and an understanding of birds’ behaviour patterns. In short it requires a wildlife detective story.
On Sunday 26th June several of us Otmoor regulars were standing and watching from the second screen. We noticed a Bittern fly into a certain spot in the reedbed but there was nothing unusual in that. Within five minutes it was seen to fly away from the same spot, still nothing unusual; we had been seeing Bitterns all year, albeit occasionally and infrequently and they are always secretive. It flew out over the Flood Field and we assumed that that was our Bittern sighting for the day. Twenty minutes or so later we saw it fly in again to the same spot as it had landed in before and within a few minutes it flew out again and off in a different direction. Within half an hour it was back again before flying off again ten minutes later. Our interest was now well and truly pricked. There seemed to be no reason for it to come and go so regularly and to be going off in different directions between visits. Unless of course it was a female Bittern and it was feeding young.
We contacted the Reserve staff and early the next morning David Wilding went down and watched for an hour or so and he saw the same behaviour. He was as intrigued as we were and decided to set up the high seat on the bund, from where movements could be monitored and logged. We had been confused by the Bittern sometimes heading to a different spot in the southern reedbed rather than where we had first seen it going into the northern sector. Careful watching soon explained this anomaly.
|Above and below: Bittern A was readily identifiable by the missing primarys.|
Both photos courtesy of Terry Sherlock.
With any piece of research, it is not enough to make a hypothesis, carrying out research and gathering data is the hard spadework that proves the argument. Terry Sherlock, Paul Greenaway and Alan Parfitt spent hours watching the comings and goings of Bitterns in both sections of the reedbed. It soon became apparent from their observations that there was not just one individual making these regular flights but two. Careful examination of the abrasion and the nicks and gaps in their wing feathers enabled us to identify them as Bittern “A” and Bittern “B”. “A” going to a spot in the northern section and “B” to the south. We realised that we didn’t have just one active nest, but two!
|Above and below: Bittern B. (courtesy of Terry Sherlock)|
|Juvenile Bittern Otmoor 2016 (courtesy of Terry Sherlock)|
|Above and below: Juvenile Bittern (courtesy of Terry Sherlock)|
“Aplin (1889) believed that the Bittern formerly bred on Otmoor and in the low swampy country which at one time formerly bordered the upper reaches of the Isis”
The Birds of Oxfordshire. Brucker, Gosler and Heryet.
This leads us to believe that the Bittern went extinct as a breeding species in the early part of the nineteenth century before Otmoor was drained and now it is back, as the consensus view is that this year Bitterns bred once again on the moor. We do not know how many birds were raised nor do we know the exact locations of the nests and even if we did there would be very little left of them by now. We did not experience a sustained period of booming but we have had a second hand report from Oddington of “several evenings booming from the Otmoor reserve direction in late February”. The males go quiet and move on once they have first attracted and then mated with a female. It may even be possible that the females mated elsewhere although this is not necessarily held to be conventional Bittern behaviour.
When the reedbed was first designed and constructed we were informed that the it was the size that it was, because it was thought at the time, to be the acreage required for Bittern to breed. I remember talking to a number of people who thought that this was a pipe dream, a bit of smart publicity, that Bittern was a flagship species that had a recognised name and other species that were less “sexy” would come in under its banner. Of course this has happened for many more common wetland species but has also happened for special birds like Common Cranes and Marsh Harriers. They too have taken advantage of the habitat, the latter more successfully so far than the former.
|The formation in the 1990's of what would become suitable habitat for breeding Bitterns (courtesy of Peter Barker).|
That this breeding has happened is yet another tribute to the way that the reserve has been managed and developed both by the full time staff, both current and past, and by the army of willing volunteers who work to help maintain it. That we have been able to prove that this breeding has happened is down to the hours of patient and painstaking observation by Alan, Paul and Terry and reserve staff. Terry’s superb photographs have played a crucial role in discriminating between the different individuals.
With the return of Bittern to the list of Oxfordshire breeding species joining Marsh Harriers and Bearded Tits, Otmoor Reserve is playing a major part in rewilding Oxfordshire and acting as a reservoir for rarer species. If one had to speculate what next, perhaps Great White Egret or Little Bittern might fit the bill, both have colonised the Somerset Levels, from where our Cranes originate and from where the Bittern population has been pushing out. Whatever it is, we will be there watching and waiting.
Peter Barker Otmoor Birding