Clive F. Mann161

Bull. B.O.C. 2013 133(2)First record of Oriental Cuckoo Cuculus saturatus optatus
in Africaby Clive F. Mann
Received 25 January 2013

While examining specimens at the Natural History Museum, Tring, for a monographon cuckoos (Erritzøe et al. 2012) I discovered a hepatic female Oriental Cuckoo Cuculus
saturatus optatus specimen (BMNH 1911.12.23.966), collected by Boyd Alexander in Zambia(near the confluence of the Zambezi and Kafue Rivers, close to the modern border withZimbabwe) on 27 December 1898. He did not label it to species, but subsequently it waslabelled C. canorus (Common Cuckoo) and placed with the African Cuckoos C. gularis.
However, he did identify it as canorus in a paper (Alexander 1900) that was subsequently
mentioned by Benson (1956).
The most noticeable features are the heavy dark barring on the deep rufous-chestnut
rump and uppertail-coverts, with no pale feather tips, and the broader dark barring on theventral surface. Hepatic female Common Cuckoo has little or no barring on the rump anduppertail-coverts. Hepatic juveniles of the latter are barred, but each feather has a narrow
whitish tip, and the rufous-chestnut is generally paler. Hepatic juvenile African Cuckoo ismuch less rich, often with some grey admixed. The ventral barring of the Alexander skin isbroader than that of Common or African Cuckoos. The two subspecies of Oriental Cuckoo(nominate and optatus) are extremely similar (Figs. 1–2), being reliably separated only bymeasurements or perhaps vocalisations. The wing length of Alexander’s specimen (224mm) places it in optatus rather than the nominate (Table 1).
Madagascar Cuckoo C. rochii and Lesser Cuckoo C. poliocephalus can be eliminatedon size. Red-chested Cuckoo C. solitarius, Black Cuckoo C. clamosus, African Cuckoo C.
gularis, and the two subspecies of Common Cuckoo, C. canorus bakeri and C. c. bangsi, canbe eliminated by plumage.
Characters that indicate optatus.—The rump of the Alexander skin lacks pale tips tothe dark feathers. Hepatic adult female Common Cuckoo has almost completely unbarredrump / uppertail-coverts; hepatic juvenile has dark bars, but the feathers have small whitishor grey tips. Both subspecies of Oriental Cuckoo (nominate and optatus) lack these tips. The
ratio of the width of dark to pale bars on the ventral surface of Alexander’s specimen is
0.751 (versus C. c. canorus 0.321–0.573, n = 30; C. c. subtelephonus 0.316, 0.355, 0.465, n = 3; C.
c. bakeri 0.483, 0.654, n = 2; C. s. optatus 0.605–1.21, n = 16). Five dark and five pale bars weremeasured in the mid-chest area, and the means calculated, which were then used to calculate
the ratios (from hepatic female / juvenile specimens at the Natural History Museum, Tring).
Furthermore, the Alexander specimen matches the wing formula for saturatus given byPayne (2005). However, the wing formulae of canorus and saturatus are very similar, and I
found them to be unreliable for separating the two species over long series.
Distribution (from Erritzøe et al. 2012, and references therein).—Oriental Cuckoo C. s.
saturatus Blyth, 1843. Southern Himalayas, north and east Burma, Thailand to China southof 32°N, including Taiwan and Hainan. Winters in South and South-East Asia, GreaterSundas, Philippines and western New Guinea. Some vagrancy. C. s. optatus Gould, 1845.
European Russia east of 45°E to Pacific coast, south to Kazakhstan and Mongolia to north of32°N in China. Winters and migrates through South-East Asia, Sundas and Philippines east
to south-west Pacific and Australia. Much vagrancy, with two records in Israel, in August© 2013 The Authors; Journal compilation © 2013 British Ornithologists’ Club

Clive F. Mann

162

Bull. B.O.C. 2013 133(2)Figures 1–2. Dorsal and ventral views of, left to right, Alexander’s specimen (BMNH 1911.12.23.966); Oriental
Cuckoo Cuculus saturatus optatus; C. s. saturatus; Common Cuckoo C. canorus canorus; C. c. subtelephonus; andAfrican Cuckoo C. gularis (Harry Taylor © Natural History Museum)© 2013 The Authors; Journal compilation © 2013 British Ornithologists’ Club

Clive F. Mann

163

Bull. B.O.C. 2013 133(2)TABLE 1
Mensural data (wing, tail and bill) from Cuculus specimens at the Natural History Museum, Tring,
including Alexander’s specimen (BMNH 1911.12.23.966) collected close to the modern-day Zambia /Zimbabwe border.
Mensural datatail length (mm)wing length (mm)(max. chord)rangemean sdn=range1167

mean sdbill to skull (mm)n=range122.9

mean sdn=Alexander’s specimen
224
Cuculus saturatus saturatusmale
174–194

183.4

± 5.8

35

113–152 136.4± 11.735

17.9–22.1

20.5

± 1.1

21

C. s. saturatus female

163–190

175.4

± 8.2

15

113–152 136.6± 10.615

18.5–23.0

20

± 1.4

11

C. s. optatus male

214–223

218.4

± 1.9

26

128–173 156.7± 11.816

19.7–24.6

22

± 1.7

17

C. s. optatus female

213–222

216.9

± 2.3

16128–168 142.6± 11.814

17.9–23.7

20.9± 1.718

C. canorus canorus male

213–230221± 4.352

170–186 177± 4.152

25.5–31.2

27.7± 1.552

C. c. canorus female

204–216210± 3.735

158–177 167

± 5.6

35

25.2–28.6

26.8

± 1.0

35

C. c. subtelephonus male

201–249221.9± 15.2 300

25.2, 26.2

C. c. subtelephonus female

180–223200.5± 13.1 180

24.7–27.0

26.2

± 1.1

C. c. bakeri male
C. c. bakeri female(no hepatic morph)

198–232

214.3

± 9.9

160

195–215205.1

± 6.8

90

199–215

206.7

± 6.2

70

24.5–29.5

26.9

± 1.0

12

194–207

200.6

± 5.4

50

25.9–28.2

27.2

± 1.2

6

204–226

215.3

± 8.4

9

143–166 152.9± 10.89

20.7–23.6

26.1

± 0.5

9

197–209

205.3

± 5.1

10

141–156 147

± 5.5

9

19.0–22.4

20.7

± 1.2

9

C. c. bangsi male
C. c. bangsi female(no hepatic morph)
C. gularis male
C. gularis female(no hepatic morph)

12400

TABLE 21985 (Shirihai 1996) and April 2008 (www.
Wing formulae data for relevant Cuculus taxa. The
israbirdig.com/israelbirdsforum), being
formulae for saturatus, optatus, canorus and gularis are
the closest to Africa.
from Payne (2005). However, in long series I foundCommon Cuckoo C. c. canorus
them to be an unreliable discriminant.
Linnaeus, 1758. Palearctic from Ireland toWing formulae
Kamchatka and Japan. Winters equatorial(except Alexander’s specimen,Africa, India and South-East Asia. C.
from Payne 2005)
c. bangsi Oberholser, 1919. Iberia andAlexander’s specimen
P 8>9>7>6>5>4>10>3>2>1
Maghreb. Probably winters Africa south
P 8>9>7>6>5>4>10>3>2>1of equator. C. c. subtelephonus Zarudny, C. saturatus saturatus
P 8>9>7>6>5>4>10>3>2>1
1914. Transcaspia to west and north C. saturatus optatus
China, Iran and Afghanistan. Winters C. canorus canorus
P 8>7>9>6>5>4>10>3>2>1
Middle East, India and Africa south of C. gularis
P 8>7>9>6>5>4>10>3>2>1
Sahara. C. c. bakeri E. Hartert, 1912. Northeast Indian Subcontinent, Assam, Nepal,
Bhutan, northern South-East Asia, south-east Tibet and south China. Winters India andSouth-East Asia.

© 2013 The Authors; Journal compilation © 2013 British Ornithologists’ Club

Clive F. Mann164

Bull. B.O.C. 2013 133(2)Conclusion
Although C. s. optatus has an easterly migration route, it is prone to vagrancy andhas been recorded twice in Israel (Shirihai 1996; www.israbirdig.com/israelbirdsforum).
Some Cuculus are notoriously difficult to distinguish in the field unless vocalising. Birdsof this genus are infrequently trapped in mist-nets, and birds that die in Africa are usuallyscavenged very quickly. Thus species such as Oriental Cuckoo may occasionally occur
in Africa undetected. The specimen in question, although quite distinct, could easily bepassed off as Common Cuckoo. Field observers would not normally consider identifying acuckoo in Africa as Oriental, due to the lack of precedent, but I urge them to consider thispossibility in the future and attempt to capture any Cuculus that does not match the known
local species. Collections may also benefit from closer scrutiny.
Acknowledgements
I thank Robert J. Dowsett for his encouragement and advice, and with Robert A. Cheke, for refereeing thiscommunication. Gratitude is expressed to Robert Prŷs-Jones and Mark Adams for access to specimens at theNatural History Museum, Tring, and to Harry Taylor, also of the Natural History Museum, for providing
the photographs.
References:
Alexander, B. 1900. An ornithological expedition to the Zambezi River. Ibis (7)6: 70–109.
Benson C. W. 1956. A contribution to the ornithology of Northern Rhodesia. Occ. Pap. Nat. Mus. S. Rhod.
21B: 1–51.
Erritzøe, J., Mann, C. F., Brammer, F. P. & Fuller, R. A. 2012. Cuckoos of the world. Christopher Helm, London.
Payne, R. B. 2005. The cuckoos. Oxford Univ. Press.
Shirihai, H. 1996. The birds of Israel. Academic Press, London.
Address: 53 Sutton Lane South, London W4 3JR, UK.

© 2013 The Authors; Journal compilation © 2013 British Ornithologists’ Club