Category: Raptors

A ‘new’ White-tailed Eagle travels the length of the county and this time … the eagle has landed.

Following last week’s overview of White-tailed Eagle occurrences in Northamptonshire, another individual, radio-tagged male ‘G393’ from the Isle of Wight reintroduction scheme, made a more prolonged visit to the county during 13th-14th April. During its short stay, it was seen by only one person and photographed.

This bird’s late March and early April wanderings have been documented here. It was one of the two birds that was in the North York Moors before moving south and covering 223 miles over two days. It then entered Northamptonshire north-west of Hellidon, late in the afternoon of 13th, before choosing a roosting site in a line of trees on farmland between Maidford and Little Preston.

It left its roost site the following morning, drifting east through the county, dropping briefly into a field just south-east of Northampton at 12.15. Somewhat amazingly, it appeared to have passed over unnoticed until, continuing north-east, it was spotted at 13.00 by eagle-eyed Steve Fisher, who was watching the skies above the Nene Valley from his garden in Irthlingborough. Shocked and elated, Steve managed some quick-fire shots with his camera as it drifted over Irthlingborough Lakes & Meadows LNR before it carried on north-east along the valley. A just reward for persistent lockdown garden birding!

At 14.15 it passed Barnwell, having continued to follow the Nene Valley and after this, it left the county, heading into Cambridgeshire and the Nene Washes, south of Peterborough. It subsequently ended up in west Norfolk, where it remained during the evening. If a bird this large can fly almost the entire length of the county undetected, then what else are we missing!

I would like to thank Dr Tim Mackrill (@timmackrill) of the Roy Dennis Wildlife Foundation for providing updates, tracking data (and maps via RDWF/Forestry England) and Steve Fisher (@stanwicktramp) for additional information and images.

POSTSCRIPT

Did you know … Pete Campbell, Proprietor of Cherwell Ironwork Ltd and well-known ex-Northamptonshire birder, made the cages for the young eagles in Charwelton and helped babysit them on the Isle of Wight prior to their release.

Is White-tailed Eagle the ultimate local rarity? If not, then it must certainly be the most majestic. Few of today’s birders – possibly only four, in fact – have seen one in the county …

A spate of sightings across southern and eastern England during late March and early April relates in part to four wandering juveniles, ringed, radio-tagged and released on the Isle of Wight in the first stage of a new reintroduction program for this species. The recent movements of each of these individuals have been detailed by Roy Dennis here and one of these birds, ‘G318’, a female, was tracked as it entered Northamptonshire airspace, from the south, during the afternoon of 4th April. At approximately 14.00, it was logged east of Daventry, moving north at an altitude of 521 metres, before eventually roosting in a wood near Grimsby, Lincolnshire during the evening.

However, there have been other sightings of juveniles which are not attributable to any of the above four individuals and it is believed there could be as many as four or five continental birds wandering around the UK, including a metal-ringed bird which is thought to be from Sweden.

It’s been just under two weeks since one of these was seen at Kings Cliffe, in north-east Northants. It was initially thought to be a Golden Eagle, although the tail shape rules that species out and, set in the context of all the other recent sightings, White-tailed Eagle is clearly the species in the frame. Michael Bunting was the lucky observer.

The above bird was also reported as still being in the area on 31st March and may well have been the bird seen and photographed by Mark Hawkes as it moved south-east, mobbed by corvids, over Grafham Water and Perry, Cambridgeshire on the morning of 2nd April. Grafham is little more than 30 km south-east of Kings Cliffe … as the eagle flies.

Prior to this, there has been only one recent record in Northants – one in flight over Wansford on 23rd January 2005, which had toured north-east Norfolk from late December 2004 before spending several days around the Ouse Washes in Cambridgeshire in January. Richard Patient was the lucky observer on this occasion and his narrative, below, forms part of the accounts published on the Cambridge Bird Club website by several birders who were fortunate enough to connect with it.

And you have to go a long way back for the one prior to that – a site-faithful individual which spent successive winters at Blatherwycke Lake, from 1897-98 to 1901-02 and was last seen there on 16th January 1902.

According to BirdLife International (2020), the White-tailed Eagle population is increasing so, hopefully, we can expect more local records in the future.

Kestrels. Frequently seen hovering above motorway verges and over open countryside, their behaviour normally associated with the search for mammalian prey. Kestrels’ diets are not restricted entirely to mammals, though, and as well as small birds, they frequently feed on insects. These are taken to varying extents, depending on range/location and food availability and they can form a considerable proportion of diet in some cases, with beetles, dragonflies, grasshoppers, moths recorded as frequently being taken. The implication, though, is that they are taken on the ground after being spotted through hovering, or from a stationary perch.

However, as Roland Bogush’s excellent sequence of shots, above, illustrates, insects are also taken and eaten in flight. This bird was observed aerial hunting last week at Sywell Country Park. It’s not a behaviour I have knowingly seen in this country by I have observed it in migrants in Israel. So, Kestrel clearly joins prolific aerial hunters, Lesser Kestrel, Red-footed Falcon and Hobby in capturing insects in mid-air. Cruising around, picking up insects? It must surely be a lot less bovver than a hover …

An interesting Buteo at Fineshade

The amazing variability in the plumage of Common Buzzards of two widespread races – ‘our’ local buteo and eastern vulpinus (Steppe Buzzard) – is well known, with some examples of both being almost impossible to tell apart.

Confronted with one such individual at Fineshade on 2nd May, Jeff Blincow was quick to capture some images of what, he says, he wouldn’t have given a second thought to identifying as a Steppe Buzzard had he been in Africa or the eastern Mediterranean region. Having seen Jeff’s excellent photos, reproduced here, I would have reached the same conclusion. “It was obvious with the naked eye,” Jeff said, and it immediately stands out with a conspicuous light rufous tail and foxy underwing coverts.

With an apparently dark eye and barred, rather than streaked, underparts, it would appear to be an adult or near-adult. But is it a Steppe Buzzard? The rufous element to the plumage, apparently less obvious in the images than in the field, are the only pro-Steppe features, although many darker Steppes can look remarkably similar to Commons and, just to complicate matters, there is an intergrade zone in eastern Europe where the two races meet.

There are more pro-Common features with this bird, however, with the barring on the secondaries being quite broad and extending well on to the primaries which, themselves are not solidly dark-tipped (some broad barring still present immediately beyond the dark). There is also a less intense underparts pattern than exhibited by typical Common Buzzards, i.e. dark head, neck and chest separated from variable dark flanks by a whitish or vary pale breast band.

Compare the Fineshade bird with a typical Steppe Buzzard, which has narrower, finer and more restricted barring against a whiter background on the underwing. The individuals in the images below, taken by Mark Pearson in Israel in March, shows more evenly patterned underparts, although the ‘ghost’ of the underparts pattern described above is still apparent.

And a first-year individual, pale, streaked not barred and with a pale iris …

The Fineshade bird is interesting. It is likely to be ‘just’ a Common Buzzard but may also be an example of an eastern European intergrade – and we have had a relatively prolonged period of easterly winds recently …

Comments welcomed and many thanks to Jeff and Mark for their images!

Hen Harrier with ‘Northern’ trait

First seen by Ian Bartlett on 13th November, this juvenile male Hen Harrier is as much stunningly well-marked as it is difficult to catch up with.

It was next observed on 17th and has since been seen almost daily, albeit briefly on each occasion, as it flies across the South Kilworth road between the settling pond and the old railway track, at the eastern end of Stanford Reservoir. Its regular hunting area is as yet unknown so prolonged observation has not been possible and all views to date have been fleeting.

However, a series of photographs taken by both Alan Coles and Bob Bullock on 23rd have nicely captured and revealed its resemblance to a juvenile Northern Harrier. With an extensively dark face and broad – though fragmented – boa, this is a Hen Harrier at the top end of the variation scale.

Ageing and sexing it is not too difficult. The combination of a largely ochre ground colour to the underparts with relatively thin streaks, cold, dark brown upperparts and a more ‘solid’ face than an adult female puts it squarely in the juvenile camp. Adult females in comparison have a whitish ground colour to the underparts with broader, blotchier streaks, slightly warmer upperparts and a more open facial disc. Its already yellow eye indicates it is a male as juvenile females have dark eyes.

Check out the contrast between the dark head/neck/boa/upper breast and the remainder of the pale underparts. It’s very marked and this is the initial, big, eye-catching, pro-Northern feature, as is the deeply solid dark brown face pattern with dark lores and the plain buff leading edge to the wing, formed by the underwing coverts.

While initially this may be enough to set pulses racing, more detailed examination reveals that there are only five dark bars on the longest primaries (Northern usually has 5-7, Hen 4-5), the dark subterminal tips to the underside of the inner primaries are strong (weaker and paler in Northern), the middle dark bar on the underside of the secondaries is broad (usually thin in Northern) and the ground colour of the underparts is too light (rustier in Northern).

So it’s an interesting-looking bird, an individual at the dark end of the Hen Harrier variation scale – and a nice bird for the county. It would be even nicer if it stuck around long enough to watch it hunting!

Hen Harrier is a scarce migrant and winter visitor, which averages 7 records a year in Northamptonshire. Its status appears stable in this context, despite persecution on moorland further north.

Jennifer Anderson will shortly be running a course  on Raptors in the library at Higham Ferrers. The course consists of six modules and covers the Conservation, Ecology, Biology and  Anatomy, life cycles, endangered species and the history of mans association with birds of prey. The course starts on 7th October and runs for six Fridays from 1-2 pm.
The cost is £5 per session and tea and coffee will be provided. See below for contact details.

 

When I saw my first Marsh Harriers at Minsmere in the early 70s I felt privileged. They were one of the rarest breeding species in Britain and records in Northamptonshire averaged one per year. Thankfully their numbers have increased, and with the current UK population numbering around four hundred pairs, they have become much more frequent in the county. If I see one locally, or anywhere else for that matter, I still feel privileged as they are magnificent birds and great to watch hunting over European meadows or migrating with other raptors high over the arid mountainous terrain of the middle east. That is one thing which will never change.

Down to earth and local. There are few good images of Marsh Harriers in Northants but yesterday Alan Coles managed to capture some of the second calendar year male which has been hanging around at Summer Leys, on and off, for the past couple of weeks.

This young male is still showing much immaturity – particularly on the upperparts, which retain extensive pale yellowish mottling on the mantle and forewing. Some male characteristics are clearly evident, though, with greyish-spotted primary coverts, and largely grey tail.

It still has a diffuse ‘female-type’ head pattern and largely dark underparts, although the ‘male’ pale greyish secondaries and inner primaries with broad blackish tips are prominent. Males are essentially polymorphic, with some adult males appearing identical to adult females.

In Northants we have seen an increase in records over the past twenty-five years, with ‘good’ years producing in excess of thirty records, although individuals are mobile and may or may not be present for extended periods, so actual numbers are difficult to determine. Our first wintering bird was in the Nene Valley – predominantly at Stanwick GP – during 2001-2002.