Identification of female and juvenile Pallid and Montagu's Harriers

A recent trip to Batumi in Georgia (which is written up below) provided a great opportunity to observe migrating harriers and to experience the difficulties of identifying them. 

At some locations it is possible to have multiple sightings of the same bird, particular if you are visiting a breeding territory but on migration each bird typically passes you just once, and in the case of harriers this is usually quickly or very quickly! Consequently you have a short period of time in which to both identify and age each bird. Clearly this is assisted by taking photos and my first recommendation is to get photos of any harrier where its identity is uncertain.

We spent 11 days at Sakhalvasho and counted 242 harriers of which 23 were recorded as Pallid, 60 as Montagu's and 159 as Monpal (not specifically identified, either Pallid or Montagu's). Interestingly during those same 11 days the Batumi Raptor Count recorded 997 harriers with 63 Pallid, 362 Montagu's and 572 Monpal. I imagine we missed a large number of distant birds as, understandably, we were more interested in watching the closer birds and attempting to get photos.

I've gone through all my photos since returning home and consequently have changed the identity and/or age of some of the birds seen now that I have been able to look at them closely and review them against the literature and the large number of published photos, particularly on eBird.

I will not be addressing the separation of Pallid and Montagu's from Hen (or Northern) Harriers which is adequately covered elsewhere and given a decent view should not normally cause confusion although birds in moult can be a pitfall for the unwary.

Nor will I deal with adult males as again they are unlikely to be confused in even a half decent view.

My comments largely relate to birds in autumn although most of the identification criteria should apply at other times of the year.

Location and date are useful factors when dealing with a possible Pallid or Montagu's Harrier, in the UK a Monpal seen between October and April is very likely to be a Pallid Harrier. This is probably also the case for most of Northern Europe.

Below I have created montages of some of the birds seen and will go through the identification and ageing criteria I have used.

All the photos were taken at Batumi in September (unless stated otherwise), the light here is very variable and it was often very overcast quite unlike the conditions usually experienced in Southern Europe or the Middle East.

As a general comment I did not notice any structural  or behavioural differences between the birds seen and do not think that size, shape or flight action are much help in identifying lone birds.

Pallid Harrier generally has a shorter outer primary (p10) than Montagu's but the difference does not appear to be sufficient to help in separating the two species.

Banding on the underside of the tail may provide additional support for the identification of both adults and juveniles. In female/juvenile Pallid the distal dark tail band is broad with a second band visible at the tip of the undertail coverts (PA1, PA3 and PJ4). In Montagu's the banding is slightly narrower with three bands visible between the undertail coverts and the tail tip (MA3, MJ3) but this feature should be used with caution.

Ageing and Sexing

The iris colour of juveniles is a safe means of separating males from females it is brown in females and yellow during a males first autumn.

Females in their second calendar year may still show a dark eye but some are already yellow eyed. The adult female Pallid PA1 is just showing a paler iris whilst the second calendar year Montagu's MA4 already has a bright yellow iris.

In the autumn of their second calendar year birds can be aged by the mix of adult and juvenile feathers.

Adult and Second Calendar Year Females

Recommended criteria, as marked on PA1 below;

Figure 1 Adult female and 2nd calendar year female Pallid v Montagu's Harrier

a) Pattern and colouration of the secondaries

On adult female Montagu's there are at least two visible dark bars on the underside of the secondaries which are evenly spaced, and the pale area separating them continues to the birds body. In Pallid the distal dark bar often thickens towards the body causing the pale bar to narrow, often disappearing before it can meet the body.

In second calender year birds there may be a mix of new barred secondaries with older dark juvenile secondaries.

From above the secondary bars can be seen on Montagu's but not on Pallid and female Pallid shows some dark marks on the rump, as does the adult male, which is not shown by Montagu's.

Pallid Harrier ad female note lack of obvious barring on the secondaries same as PA1

b) Primaries

On Montagu's the inner five primaries are dark tipped whereas these, particularly the inner 3 or 4, are pale like the rest of the feathers.

In second calendar year females the inner 7 or 8 primaries have usually been replaced by autumn leaving 2 or 3 outer primaries which are retained, worn, juvenile feathers.

c) Underwing coverts and axillaries

The axillaries on Montagu's are barred pale and dark brown or reddish brown and in adult females this pattern is repeated across the greater underwing coverts. An example of the longest axillary is inset by the carpal joint on figures MA1 and PA1.

The overall effect is often to create a strongly barred pattern in female Montagu's, MA4 is a good example. MA5 is a darker second calendar year bird and the darker 'armpit' is more akin to Pallid but note the axillary pattern is still Montagu's.

In Pallid these feathers are dotted rather than barred and the colouring tends to be more subdued although on reddish birds such as PA3 it can create a strong pattern which could be mistaken for that of Montagu's but a close look shows that these are discrete spots rather than bars. 

Where the bars are not aligned it creates more of a chequer board effect as in Figure MA1.

d) Head pattern

The pale collar, which is a feature of juvenile Pallid harriers is retained in to adulthood by the female Pallid Harrier although it is not as obvious as in the juvenile but usually forms a crescent of even width behind the dark sickle shaped cheek surround.

There tends to be less contrast in female Montagu's head pattern the dark cheek surround is darkest behind the eye but tends to merge in to the dark neck colouration to the rear and below.

The dark head of MA5 is more Pallid like but there is less white in the sub-ocular area and there is no pale collar.

There is a lot of variation in the plumage of female Montagu's Harrier, in particular, and identification should be confirmed on a combination of features.

 Juveniles

Visiting Batumi I knew that separating adult female Monpals would be tricky but I found that juveniles were often just as problematic. In part due to the distance from the bird and the poor light, but the variation in juvenile plumage of both Montagu's and Pallid Harriers was greater than expected and there is considerable overlap in many of the features used to separate them.

Figure 2 Juvenile Pallid and Montagu's Harriers

The ground colour of both species varies but Montagu's shows the greatest variation, ranging from deep brick red, as in MJ3, which I've never seen in Pallid, to a less frequent pale yellow-beige which is more akin to the commonest colour of Pallid.

As with the adult female I'll go through the key identification features for both species which are lettered on Figure 2 against PJ1.

a) Secondaries

Juvenile Pallid Harrier commonly shows all dark secondaries as in PJ2 and PJ5 but they can be paler when dark barring may be visible as in PJ3 and some male Pallid Harriers show paler, dark barred secondaries similar to Montagu's MJ1.

b) Primaries
Both species show dark tipped primaries but the dark area is much more extensive in Montagu's, often covering more than half the outer primaries, whilst it is generally just the tip in Pallid.

Male Montagu's Harriers, and sometimes females can show larger unmarked outer primaries (p10 to p8)  below the dark tip creating a large pale area in the outer wing which is visible from a considerable distance as in MJ1 and MJ3. I have not seen this feature in Pallid so if present is strongly indicative of Montagu's. 

On the other hand the base of juvenile Pallid Harriers primaries may show no barring as in PJ3 which creates a so called pale 'boomerang' at the base of the primaries which I haven't seen in Montagu's.

The inner primaries of Pallid may look translucent, lacking dark tips as in adult female Pallid and it may be that this is more commonly found in female Pallid as in PJ1and PJ4. 

Some Pallids do have darker tipped inner primaries and some Montagu's, which typically have dark tipped primaries as in MJ4 and MJ1, have pale tipped inner secondaries as MJ2 so this is not a feature to rely on.

c) Underwing coverts and axillaries

The underlying colour of the underwing coverts and axillaries generally matches the body colour but in some Pallid the greater underwing coverts are dark as in PJ4 and PJ5 forming a distinct line in the centre of the underwing, I haven't seen this in Montagu's although they might show dark shaft streaks as in MJ2.

Juvenile Montagu's may have some adult like axillaries and/or greater underwing coverts as in MJ1, MJ4 and MJ5. Although Pallids may show indistinct spotting on the axillaries they never show the strong pattern as seen on the examples above. So birds showing one or more strongly barred, or spotted, feathers is likely to be Montagu's.

d) Head pattern

The majority of juvenile Pallid Harriers exhibit a pale, even width, collar bordered by a dark sickle shaped cheek crescent towards the eye and a dark 'boa' of variable width towards the body as can be seen in all the juvenile Pallids on Figure 2.

Juvenile Montagu's may also show a collar but it is seldom as distinct as in Pallid compare MJ1, MJ2 and MJ5.

Conclusion

Given a decent view most female and juvenile Pallid and Montagu's Harriers should be identifiable.

Get a photo if possible and note the markings of the primaries, secondaries, underwing coverts and the head.

I've made no attempt to consider hybridisation which is known to have occurred between Hen and Pallid Harriers and Montagu's and Pallid Harriers.

I have produced a single sheet key to harrier identification which I've reproduced here;

Simplified key to harrier identification

References

Forsman D, (2016)

Flight Identification of Raptors of Europe, North Africa and The Middle East

Forsman D, Dutch Birding 17:41-54, April 1995

Field identification of female and juvenile Montagu's and Pallid Harriers

Dobler G, (2022)

Field identification of the Hen Harrier, Montagu's Harrier and Pallid Harrier

Croatia 28th May - 9th June

We crossed the impressive toll bridge on to the island of Krk on the afternoon of 28th June and drove down to Krk town where we booked accommodation at Ana Rooms via Booking.com for 65€ (~£58) for 2 nights. The property was within easy walking distance of the centre and close to open countryside in a modern elegant property. I took a walk along a track into a maze of walled olive groves. A Cirl Bunting was singing from the top of a bush and I soon heard several Eastern Subalpine Warblers. I returned to the same area the following morning with a light rain still falling and added Red-backed Shrike plus a distant Lesser Grey Shrike. The latter was rather frustrating as it was sat in the open on top of a bush but the maze of deep drystone walls made it impossible to get closer. Sardinian Warblers were also present with the Eastern Subalpines. 

Cirl Bunting - male in song

The following morning I returned to the Krk Airport area where I had searched in vane for Rock Partridge in 2016.

Krk dry stone walls- the ground was covered in rocks and I concluded they just piled them up to clear the ground?

The signs were not good with heavy rain showers and almost gale force wind. Pam and I trudged up and down the area east of the quarry but it felt hopeless. We disturbed at least 6 Red-backed Shrikes which were sheltering close to the ground out of the wind but couldn't find the partridge. A single Eastern Black-eared Wheatear flew towards the quarry but in the weather conditions there seemed little point in pursuing it so we left the area heading south again hoping for more luck on the island of Pag.
We decided to stay at Nin for four nights at Apartments Ventura which were opposite the small island town of Nin and 
right on the coast. The weather finally started to improve and we enjoyed glorious sunshine here.
On Nin itself there was a large colony of Spanish Sparrow by the church and a pair of Woodchat Shrike.

Woodchat Shrike - female

Nin was badly flooded in 2017 and they were still repairing some of the access roads including that which ran parallel to the salt pans which made access to that area difficult although other than Little Terns and Black-winged Stilts there did not appear to be much bird activity.

Aerial view of the 2017 flooding at Nin on a poster at the town entrance

As we drove in to Nin Pam saw a Pygmy Cormorant sat on a rock close to the old town and subsequently we saw 2 or 3 everyday sat on posts or this same rock.

Pygmy Cormorant

A short walk from the apartment was some open ground with scattered trees, Turtle Doves and Nightingales could be heard with the occasional flutey whistle from Golden Oriole. Several pairs of Red-backed Shrike were courting and I came across a pair of Eastern Subalpine Warblers feeding young in a nest. The female was very elusive but the male came along the tops of the bushes to the nest giving some excellent views. He brought a range of different sizes of spiders, small butterflies and quite a large grasshopper of some kind.

Eastern Subalpine Warbler - male with a cricket

Eastern Subalpine Warbler - male

The male Red-backed Shrikes were very vocal giving a short croaking call that I can't recall hearing before and were clearly in courting mode as they were regularly chasing the females.

Red-backed Shrikes - male and female

From Nin we drove down the coast through Zadar to Lake Vrana. There is a conservation area on its northern edge with a decent boardwalk which gave good views of the lake and the reed bed. Pygmy Cormorants were flying past in ones and twos and there were marsh terns feeding over the lake including both White-winged and Whiskered Terns but they were always distant. Purple Herons kept appearing over the reed beds then disappearing in to them again. From the reeds Great Reed Warblers were calling incessantly with the occasional Cetti's Warbler. A couple of male Montagu's Harriers drifted northwards high over the lake and we also saw singles closer to Nin.

Montagu's Harrier - male

The following morning I got up early and drove round to the island of Pag. There are two linked wetlands on what is otherwise a very barren island so I headed for Veliko Blato which has open water and reed beds.

Sign at Veliko Blato

The edge of the lake is easily accessible and this held several Squacco Herons feeding amongst the sheep. 

Squacco Heron

There were also Crested Larks here and a few waders with singles of Wood Sandpiper and Little-ringed Plover I also saw several Lapwing in a wet area by the main road as I turned off to Veliko Blato. The only raptor was a rather tatty female Marsh Harrier and it was clear that I was at the tail end of migration here although small parties of Bee-eater were still moving. I stopped at various spots for Rock Partridge but without success.
The following morning I had another look around Nin, close to the salt pans I came across a hippolais warbler in song. It was sat out in the open but frustratingly, due to dense vegetation, I couldn't get very close. The song lacked the wheezy nasal elements of Icterine, not sure why its named Melodious though as it was still fast and scratchy. The primary projection was short, pale wing panel very narrow and buffy yellow underparts with yellow restricted to throat so all good for Melodious.

Melodious Warbler

Later that day we drove to Starigrad with a view to driving up to Veliko Rujno but the narrow road had suffered a landslip in the village and was impassable. I tried to find an alternate road to link up above the landslip but nothing connected so we entered the main Paklenica Park entrance. There were many climbers and few birds. Having walked fairly well up the gorge I tried in the low wooded area near the park entrance and soon found a singing Icterine Warbler. Croatia is one of the few countries where their breeding ranges overlap and seeing both species the same day was a real treat. The Icterine had a striking wing panel (although I've recently seen photos of Melodious with a distinct wing panel in the Netherlands so this is not a diagnostic feature). Primary projection was very long, equal to the exposed tertials and the underparts were a more uniform yellow and it looks like a short 1st primary is just visible. The song contained the characteristic repeated wheezy nasal elements.

Icterine Warbler

After leaving the park I had another look for a road up to Veliko Rujno and finally found an alternate route. Stops on the way up produced more Eastern Subalpine and where the paved road ends I had rather poor views of two Eastern Orphean Warblers, calling tack tack which to my ears was the same as Blackcap but no song.
We had a last day at Nin on 2nd June and made another trip to Pag. At a small supermarket at the entrance to Povljana there were both House and Spanish Sparrows together and I saw mating House and mating Spanish but no interspecies mating and no sign of any hybrid birds.

House and Spanish Sparrows

Spanish Sparrows courting with House Sparrow looking on, note the blackish throat on this female

I Left Pam by the beach at Povljana and drove over to Veliko Malo, just as I left the shoreline a Rock Partridge flew over the road in front of me and appeared to land in a rocky field.
I parked up and scanned the field, no sign. I waited and after several minutes it appeared below a bush, stood still for 30 seconds then moved out of view.

Rock Partridge

I waited another 15 minutes with no further sign then I heard a second bird calling some distance away and picked it up on top of a wall. It was distant but stood out in the open, Rock Partridge at last.

Rock Partridge

Whilst they may not be guaranteed on Pag or Krk the chances of seeing them and getting decent views appear a lot higher than on the hills of Paklenica or for that matter the French or Swiss Alps.

Rock Partridge habitat on Pag

The following day we moved to Camp Igor on the coastal southern edge of Starigrad. Early the next morning I walked up a paved road just south of the campsite and almost immediately heard the flutey song of Eastern Orphean Warbler, then another and within half an hour I counted at least six singing males. They appeared to choose the tops of the tallest trees as song post but after an hour or so I managed some reasonable photos.

Eastern Orphean Warbler - males

All the males I saw had irises that were only a slightly lighter blue grey than the pupil. The dark blotches on the under tail coverts are just visible on the lower bird as well as the extensive bluish bill base which help to distinguish Eastern from Western Orphean.

From Starigrad we started to head back north stopping at a large but empty campsite by the pretty fishing village of Klenovica and then continuing on to Pula in Istria where we stayed in Apartment T&S off Booking.com €124 (~£111) for 4 nights. A couple of km from Pula centre but walkable.

Pula amphitheatre

The amphitheatre at Pula is certainly spectacular and its a decent town centre. Nearby a promontory sticks out in to the Adriatic which forms the southern tip of Istria and is a protected area called Kamenjak. At times in the spring it must be alive with birds but Pam and I had the usual Eastern Subalpine Warblers, Red-backed Shrikes plus Woodlark and Tawny Pipit with lots of Shag off shore and a couple of orchids but apparently there are 30 species to be found here.

Tawny Pipit

 About 30km to the north of Pula there is another reserve, a coastal swamp called Palud. There were very few birds and lots of mosquitos when we visited but I could imagine it pulling birds in when the weather is right.

Palud reserve from the small hide

We saw Shelducks, Eastern Subalpine Warblers this time feeding fledged young and a few Little Egrets.
After Pula we headed north back in to Slovenia but we stopped a couple of times on the way to look at wooded and scrub areas. One bird I hadn't seen this trip was Sombre Tit although we'd looked in many areas that looked suitable but had no luck, are there Sombre Tit in Istria? Stopping near Pazin we came across a lovely group of flowering Lizard Orchids before finally leaving Croatia.

Lizard Orchid

Back to Spain 4th September - 8th October 2017 Part 1 Drive to Tarifa

I left the UK in the camper late on Monday 4th September and caught the 01:45 ferry from Dover to Calais. From Calais I headed south past Le Mans, Tours and Bordeaux stopping at Bayonne close to the Spanish border. 
The following day I drove to Villafafila and was soon watching flocks of Great Bustards, some quite close on the Villalpandol road.

Great Bustard

I stopped overnight at Otero de Sariegos where I had watched Lesser Kestrels the previous Spring. There were still one or two Lesser Kestrels around but most had already left the breeding site. Some nice Booted (including adult and juv dark phases which made a nice comparison) and Short-toed Eagles passed over and I took photos of the Spotless Starlings which now included some fairly spotty juveniles.

Booted Eagle adult (left) and juvenile (right)

Spotless Starling juv moulting to 1st winter

Parties of Bee-eaters passed overhead, mostly heard rather than seen. 

Sunset Otero de Sariegos

At dusk both Barn and Little Owls were calling and I caught up with the Little as the sun rose the following morning.

Little Owl at dawn

Rock Sparrows were coming to drink at a small pool and I counted at least 15 but they were surprisingly flighty. 
As the sun rose so did the temperature and it was 37℃ by early afternoon when I headed off for Monfrague. Several Two-tailed Pasha butterflies crossed the road in the National Park and I was soon watching large groups of Griffon Vultures (50+) and a handful of Blacks. At the Pena Falcon a pair of Black Stork still occupied a nest cave but were two far away to see whether these were adults or young. A Blue Rock Thrush  came out of the shade briefly to snatch some scraps from the footpath but the Western Subalpine Warbler feeding in the bushes stuck to the shade.

Blue Rock Thrush

I drove on to Trujillo and spent the night by the Bull Ring but this time all the Lesser Kestrels and Pallid Swifts were gone so the area was much quieter. Thousands of Spotless Starlings came in at dusk to roost much as our Starling does in the UK.
I spent a few days exploring the Steppes around Trujillo and saw several parties of both Black-bellied and Pin-tailed Sandgrouse and managed some flight photos once I had worked out which pools they were drinking at. 

Black-bellied Sandgrouse - female

Pin-tailed Sandgrouse - male

Two Little Bustards were the only ones I saw but there were more Greats. The plains were full of larks with several hundred Calandra and lesser numbers of Short-toed. A Dotterel flying over calling was unexpected.
From Trujillo I drove to Malaga where I was due to pick up Pam from the airport on 9th September. With time to spare I went to the conveniently located Guadalhorce reserve where again I had good views of White-headed Ducks plus a few migrants including a nice male Bluethroat. Pallid Swifts and Red-rumped Swallows were passing through here as were several Booted Eagles. Red Avadavats and Monk Parakeets gave the area an exotic feel.

White-headed Duck - male and female

Having collected Pam from the airport we continued south down the coast to the Meson de Sancho hotel close to Tarifa.
Tarifa in the autumn is a fantastic place for birding. There is always evidence of some birds moving south and if you are lucky with the winds the birds of prey can pass vary close. Most days started at the Cazalla watchpoint above Tarifa but then depending whether the raptors were moving and their line of flight we might move to one of the other watch points. The Trafico watchpoint where the Spanish Fundacion Migres is based can be the best for photography as birds are funnelled down the coast before starting the crossing to Morocco. Around 50 to 100 each of Booted and Short-toed Eagles were seen most days plus smaller numbers of Honey and Common Buzzards, Black Kites plus 1 or 2 Montagu's Harriers. One day we had 46 Egyptian Vulture which was amazing.

Egyptian Vultures - adult and juvenile

In addition to the raptors parties of Bee-eaters passed overhead and several groups of Black Stork.
The beach at Los Lances is covered with people flying kites but visits early morning generally produced a few Audouins's Gulls and a few waders including Kentish Plover, Sanderling and Bar-tailed Godwit.

Audouin's Gull - moulting adult

In Tarifa itself I added Common Bulbul to my European bird list where there is a small population of this North African species.
We met Mick and Viv Cunningham who are birding friends from the UK and I was pleased to get a call from Mick to say he had found a roosting Red-necked Nightjar at La Janda. This bird has roosted in more or less the same spot for several years and is quite famous but still is very difficult to locate amongst the fallen leaves.

Red-necked Nightjar

It was general windy at La Janda making birding difficult but it did help me to get some nice photos of juvenile Montagu's Harriers as the wind held them almost stationary over the track.

Montagu's Harrier  - juvenile

Part 2 covers Tarifa to the French Alps.

Birding the Lithuanian Coast 13th - 15th May

We drove north out of Poland, stopping overnight on 13th May at a great camp site by a lake on the outskirts of Kaunas. Local birds included Icterine Warbler, Wryneck and Fieldfare all fairly standard now for parkland habitat. Not many birds on the lake but 2 pairs of Goldeneye were an indication that we were getting further north.
The following morning we drove to Vente which is a short spit of land projecting south in to the Curonian Lagoon towards the isolated Russian state of Kaliningrad and sheltered from the Baltic  by the Curonian Spit, a narrow strip of land which extends about 50km in Lithuania before entering Kaliningrad.
Vente has a bird observatory and the largest Heligoland trap I have ever seen. Approximately 100,000 birds are trapped here annually for migration studies and there are some historical records of ringing recoveries in a very smart museum which I have reproduced below.

Heligoland Trap - the supports look like stands for football stadium lights!

Letter from British Birds regarding a Starling shot in Cornwall in 1932 which had been rung at Vente!

The most striking feature of the area when we arrived was not the birds but the huge numbers of midge type flies which filled the air, fortunately they did not bite but at times it was impossible to breathe without inhaling several. Pam was not impressed, but we stuck with it and saw some interesting birds. 
Around the campsite we had Thrush Nightingales, Icterine and Barred Warbler and several Red-backed Shrike and at least half a dozen Cuckoo.

Barred Warbler - with bars, unlike the Autumn juvs I am familiar with in the UK

Cuckoo's could be heard calling all around Vente

We arrived in poor weather and there were hundreds of Ruff with smaller numbers of Wood Sandpiper and Greenshank moving north on the shoreline.
After birding locally first thing the following morning we drove a few kilometres up the coast to Kintai, where miraculously the flies disappeared, and explored a series of large lakes where we saw at least 13 White-tailed Eagles, 4 Wheatear were the first of the trip and a pair of Montagu's Harrier crossed the road over the car.

White-tailed Eagle immature taking flight

Montagu's Harrier - male

Fortunately the male circled giving me time to grab the camera and jump from the car.
A little further north at Dreverna we found habitat that looked ideal for Aquatic Warbler but all I could see were Sedge. A Honey Buzzard circled over a wood which is my first definite sighting of the Spring although a distance bird in Poland was probably a Honey.
It was raining and very windy the following morning and a short walk added Shelduck to our list and several Black Terns   crossing the spit. The area is a lot like Spurn and I'm sure in the right weather there could be hundreds of grounded migrants.
Before leaving Lithuania we called in at Palanga to have a look at the pier which is witness to a massive movement of ducks, geese and divers in March/April but apart from a handful of Common Scoter the sea was quiet. 
Common and Herring Gulls (argentatus here) were feeding along the pier which had fishermen every few feet catching what looked like some sort of Stone Fish.

Palanga Pier, with viewing seats and fishermen concentrated at the end

The object of the fishermen's attention - there must have been 50+ caught whilst I was there.

Leaving Palanga we continued north in to Latvia.