This page discusses identification of the Plain-backed and Long-legged Pipits in West Africa. Some video-grab images of birds at IITA, Ibadan, SW Nigeria in November 2002 are shown below, together with pictures from the Plain-backed Pipit skins examined at the Natural History Museum in Tring in July 2003. Please click on thumbnail images for larger versions! Short video clips follow at the foot of the page. NB - all of the field images or movies may be freely used for any non-commercial use, preferably with acknowledgement. All skins images Copyright (c) The Natural History Museum, London.
Leucophrys Bird 1:
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Leucophrys Bird 2:
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Leucophrys Bird 3:
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Leucophrys Bird 4:
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I was initially puzzled by these pipits (particularly birds 1 and 3) as they did not very well resemble the illustration and description for Anthus leucophrys zenkrii (the "Cameroon Plain-backed Pipit") described in Borrow & Demey (2001) as the Plain-backed Pipit subspecies for "central" to "eastern" West Africa (i.e. south Mali to Ghana, east to CAR); on account of the apparently pale underparts, I suspected at the time that they were in fact more likely of the western races, gouldii (the "Upper Guinea Plain-backed Pipit", for which the distribution is given as "Sierra Leone, Liberia and Ivory Coast", and which is described as "much paler below", or ansorgei (no alternative English name found), which is found in "S Mauritania, Senegambia and Guinea-Bissau" and is "greyer above" relative to gouldii.
On the other hand, birds 1 and 3 were clearly associating with birds which matched the depiction of the zenkrii race quite well, with darker buff-coloured bellies tinged with cinnamon (i.e. Birds 2 and 4 above).
Leucophrys Bird 1
Looking more closely at the first set of images, these clearly show a noticeably pale-bellied bird with other interesting plumage features to note. Firstly, the bird seems to be an adult on account of the lack of narrow whitish fringes on the upperpart feathers and coverts. However, the buff fringe is quite light, with no trace of "cinnamon" - illustrated for example in image 5. Zenkrii race birds are supposed to show "blackish-brown feathers broadly tipped and edged cinnamon", whereas gouldii has "with less cinnamon on wings". Secondly, the moustachial and malar stripes are described as "rather indistinct" by Borrow & Demey but in the field the malar strip stood out to me as distinct, marked and dark (cf. Image 3), though the moustachial stripe was not so on any of the birds. Thirdly, the breast-streaking was not particularly distinct and marked - this is perhaps the main feature in support of a zenkeri ID as "indistinct streaking" is characteristic of this race, by contrast with the more definite markings of gouldii and ansorgei. This difference is particularly clear by comparison with these presumed ansorgei birds from The Gambia (which also have distinct malar stripes!):
[Pictures kindly supplied by John Ovenden and Jim Rose, respectively]
Leucophrys Bird 2
This individual was with Bird 1 but was significantly darker below. I assumed that this was a zenkeri race bird, though there was still some paleness about the underparts.
Leucophrys Bird 3
This bird was similar to Bird 1 and also puzzling. Unfortunately the images are not as good as for Bird 1 as it was obscured by some grasses. However, it again showed a distinct dark malar stripe (Image 1), a very uniformly plain back (Image 2), darker coverts (Image 3) and faint breast-spotting (Image 4). Again, the bird was consorting with an obvious zenkeri race bird (Bird 4).
Leucophrys Bird 4
This last bird was even darker than bird 2 and showed very marked cinnamon fringes on the median coverts. Since it appeared so different to birds 1 and 3, I concluded at the time that this was a definite zenkeri individual, implying that the former weren't. However, after visiting the skin collection at the Natural History Museum I've now revised this opinion, as explained below.
Other field observations
It was noticeable that the birds were always seen as pairs - a characteristic of this species (Phil Hall, personal communication). In terms of behaviour, all of the birds shown wagged their tails very frequently. I thought that their typical calls might be transcribed as a fairly soft "chirrup" though I also noted a soft mono-syllabic "sweep" on occasion. Tail wagging is not much help in distinguishing between these and similar pipit species (see below), never mind subspecies, and neither is the call.
Other subspecies?
A total of nine Plain-backed Pipit subspecies are listed on Giles Mulholland's African species list. Another possibility considered earlier was that the pale birds were of the subspecies bohndorffi (the "Congo Plain-backed Pipit" or "Uganda Plain-backed Pipit", with alternative scientific name: A. l. prunus) described in Borrow & Demey as "similar (to zenkerii) but underparts paler". The range for this subspecies is suggested to be SE Gabon and Congo, within the West African region (clearly also including Uganda outside the region!). Neither the ansorgei or bohndorffi subspecies are illustrated in Borrow & Demey.
I was initially unable to find a single image of any of the above subspecies on the internet, though I've since noted one ansorgei race bird picture posted on the World Bird Gallery site. [Many thanks to John Ovenden for subsequently sending me the additional picture from Gambia and to Jim Rose who allowed me to use the image in his Gambia trip report of Jan 2003, source of the World Bird Gallery picture mentioned above.] The African Bird Image Database launched in August 2005 also included this this picture of a bird at Lekki in 1989 (photo by Ian Nason).
Other species?
The breast-spotting/plain back combination rules out Tawny Pipit (Anthus campestris) which in any case is an unlikely possibility due to its more northerly distribution in the savannah belt. A further possibility is Long-legged Pipit (Anthus pallidiventris) apparently occurring as near to Nigeria as SW Cameroon but it seemed this species can be ruled out on account of structure. I also initially discounted it due to distribution, but this brings us to the next topic...
Description of presumed Long-legged Pipits (Anthus pallidiventris) at IITA, Ibadan, Nigeria, November 2002
Pallidiventris Bird 1:
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Pallidiventris Bird 2:
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I was initially equally confused by these individuals as they appeared structurally different to the birds described above as Plain-backed Pipits yet were seen at the same location by the rice paddies as Birds 3 and 4. I considered an ID as Long-legged Pipit at the time but soon dismissed this due to that fact that the species was not mapped for Nigeria in Borrow & Demey, and also because of confusion with the other pale-bellied birds present - I felt it far more likely that there were all one species exhibiting some variation in plumage.
However, in July 2003 I revisited my video records and made a more detailed study. This revealed the presence of two different individuals (shown above as Pallidiventris Birds 1 and 2) at the same location, apparent as camera panned from one to the other, and also the distinctive harsh call, clearly matching that described for Long-legged Pipit (cf. the softer call of the Plain-backed Pipits).
Looking at the images shown above (Pallidiventris Birds 1 and 2), various other differences can be noted which are consistent with this being a different species. Overall, the plumage is very plain, with a very uniformly-coloured light brown back (see Pallidiventris Bird 1, Image 1, cf. Leucophrys Bird 4, Image 2 above) lacking the clearly contrasting greater coverts and secondaries of the Plain-backed Pipits. Also, the underparts are even paler without the buff on the flanks shown in the paler presumed zenkeri birds (i.e. Leucophrys Birds 1 & 3 above) and the breast spotting is yet fainter too. The eyestripe is very noticeable, being more prominent ahead of the eye than that in the sister species (e.g. Pallidiventris Bird 2, Image 8, cf. Leucophrys Bird 1, Image 3). The malar and moustachial stripes appeared quite similar to those of the Plain-backed Pipits, i.e. the former quite marked and the latter rather indistinct.
Moreover, structurally, the birds seemed to have quite a different jizz, giving the impression of being more lanky. Careful comparison with the Plain-backed Pipit images shows the neck to be distinctly longer and narrower with the beak appearing marginally longer and narrower too (though coloured similarly bright yellow on the lower mandible in both species). The legs also appear longer, particularly the tibia, and are perhaps more yellowish (see Bird 2, Image 5). In the normal stance the belly is clearly deeper giving the impression of a more tapering rear - though it should be noted that the Plain-backed Pipits occasionally puffed out their breast feathers, which could create a misleading impression in a single image (cf. Movie 3 below for Bird 1).
Other field observations
As was noted for the Plain-backed Pipits these birds were clearly a pair. In terms of tail wagging, if anything this was even more frequent than for the Plain-backed Pipits! The most interesting feature though was the distinctive call (which unfortunately did not transmit itself into the movie file - below, presumably due to frequency cut-off). This was a more vigorous "tzip", interspersed by "zip - zip - zip" very reminiscent of the song of Meadow Pipit - and presumed to be the bird's song.
On the basis of these observations, I've now concluded that these two individuals must indeed have been Long-legged Pipits. According to del Hoyo et al (2004) this species "has recently extended its range NW from Gabon to SW Cameroon and two possible sightings in SE Nigeria; expansion possibly a result of deforestation". Hence, if accepted, the above would be the first confirmed record from Nigeria, and notably a few hundred miles NNW of the Cameroon border. I have since heard that the species has also be recorded in 2004 in coastal Benin (via Bob Dowsett, personal communication) so it may be becoming more common in the region than the literature suggests (Postscript, have now prepared an co-authored account with observers of Benin bird, Marc Thibault and Pierre Defos Du Rau, for submission to ABC Bulletin).
Examination of Plain-backed Pipit skins at the Natural History Museum in Tring, July 2003
On 13 July 2003 I made my first visit the skins collections at Tring to research the racially-related plumage variation in Plain-backed Pipit. Access to the collections is free to those engaged in legitimate research, but an appointment must be made in advance. Thanks to Mark Adams for allowing me to visit and showing me round.
The Plain-backed Pipits collection was extensive, with perhaps 500+ specimens, including about 100 zenkeri race birds. The latter were from a range of countries, but most were from Nigeria collected by Dr. William Serle in the 1940s and 1950s. [A few notes on this great West African ornithologist are on this linked page.]
My first impression on looking at the trays for the zenkeri race was the apparent paleness of the underparts of nearly all specimens, for example the following (NB - all video-grab images obtained under natural, not artificial, lighting, and plumage tones not digitally edited):
These are all zenkeri birds, respectively:
- females from southern Nigeria (image 1)
- males from southern Nigeria (images 2 and 3)
- males from northern Nigeria (image 4)
- individuals from localities east to Sudan/Uganda (image 5)
Underpart colouration on most zenkeri birds seemed to differ little from that of the gouldii and ansorgei individuals and I thought I'd be hard-pressed to tell the difference in the field in most cases. More precise comparisons were made by selecting a zenkeri female and male pair which was as nearly typical as possible (shown in above overviews as the central bird on the left of image 1 and the central bird in image 3, respectively), together with single gouldii (female) and ansorgei (male) individuals which were also mid-range in terms of the paleness of the underparts:
Details of the birds shown are, from left to right:
- Zenkeri, female, Brit. Mus. Reg. 1955.59.750, collected by Dr. W. Serle at Enugu on 6/8/1954, "one of two together on the grass runway of the airport at Enugu; insects in stomach; ovary slightly enlarged" [Label front, Label back]
- Zenkeri, male, Brit. Mus. Reg. 1955.59.751, collected by Dr. W. Serle at Enugu on 6/12/1954, "a single bird in a tree in farmland in savannah; insects in stomach; testes slightly enlarged"
- Gouldii, female, Brit. Mus. Reg. 1923.11.12.287, collected by W.P. Lowes & H.R. Hardy at Beoumi, Ivory Coast on 12/12/1922
- Ansorgei, male, Brit. Mus. Reg. 1910.5.6.1245, collected by Dr. W.J. Ansorge at Gunnal, Portugese Guinea, on 15/12/1909
The first photo shows that the difference in underparts colouration is very marginal, though the zenkeri race birds are if anything the darker, as expected. The second photo, of the same birds, shows that the upperparts are also very similar in shade, though the zenkeri female is clearly slightly lighter. I could discern no difference between this particular zenkeri male and the gouldii and ansorgei birds.
Notwithstanding the above, there were a small number of zenkeri individuals which were as dark as Bird 4 observed at IITA (above), for instance the upper individual in image 3 of the trays overviews above (males from southern Nigeria). It seems that variability in underpart colouration amongst this subspecies is not insignificant (perhaps related to soil type?).
One final factor not considered is potential accumulated fade in the plumage due to exposure to the light - though this should be insignificant as the specimens are of course kept in closed cupboards (Mark Adams, personal communication).
Considering the appearance of the malar stripes on the specimens, these were typically quite distinct and continuous on the zenkeri birds, as can be seen for example in this closer view of the zenkeri male:
Finally, looking in more detail at the breast spotting, it was apparent that the zenkeri race birds generally have much more diffuse and less distinct spots. The spots on gouldii and ansorgei were even more distinct on some other individuals than the "typical" individuals shown above (cf. also Gambian picture above), e.g. the following depicting gouldii and ansorgei birds respectively:
Conclusions
- The Plain-backed Pipits seen at IITA, SW Nigeria, were almost certainly all the expected zenkeri race individuals
- The main initial confusion factor was the range of underpart darkness exhibited in the field, varying between very light buff and a dark cinnamon-tinged buff, with light and dark birds paired (and the presence of presumed Long-legged Pipits at the same locality!)
- This variation was confirmed by the skins study, though most of the collected birds were at the light end of the scale
- The underpart coloration variation may be related to soil type, but more study would be required to determine if there is also some distributional cline in this feature
- All gouldii and ansorgei race skins were very pale below, but they had more distinct breast-spotting
- The lack of distinct breast-spotting on the zenkeri race birds, including those seen at IITA, seems to be usually diagnostic amongst these races
- All three races can often show quite distinct malar stripes, and sometimes also dark moustachial stripes
- Amongst the three races, differences in the upperpart darkness in the skins was similarly marginal, being in some cases inseparable to the eye
- The West African races can therefore appear very similar to each other and it can be quite misleading to attempt subspecific ID based on underpart darkness alone
References
1. Borrow, N. & Demey, R. (2001) "Birds of Western Africa", Helm Identification Guides, Christopher Helm, London, ISBN 0-7136-3959-8 [Amazon link]
2. Serle, W., Morel, G.J. & Hartwig, W. (1977) "A Field Guide to the Birds of West Africa", Collins Field Guide, Harper Collins Publishers, London, ISBN 0-00-219204-7 [Amazon link]
3. del Hoyo, J., Elliot, A. & Christie, D. (2004) "Handbook of Birds of the World. Volume 9: Cotingas to Pipits and Wagtails", Lynx Edicions. ISBN: 8487334695 [NHBS link]
Movies section
These are brief mpeg movies of the IITA birds. Respective file sizes are indicated.
Plain-backed Pipit (Bird 1 and 2) (1, 2, 1, 2 MB)
Movie 1a, 1bc, 1d; 2
Long-legged Pipit (Birds 1 and 2) (0.4, 0.6, 1.6, 0.8 MB)
I'd welcome any further comments or advice on the identification of these birds - please send me a mail at lothianrecorder@the-soc.org.uk. In particular, there may be other literature which I'm not aware of (my references were confined to those listed above).
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