WINGFLAP DIALECTS IN THE FLAPPET LARK MIRAFRA RUFOCINNAMOMEA

The Flappet Lark Mirafra rufocinnamomea is a widespread species inhabiting lightly wooded, grassy country in Africa, and its common name well describes its most conspicuous sound. During the breeding season the birds often fly about over grassy clearings or bare areas in the open woodland and make flapping sounds with their wings. The wingflaps are more often heard than is song, and Wickler (1967) thought song in this lark had been completely replaced as an auditory signal by the mechanical sound of the wingflaps, in contrast to some other Mirafra larks that make noises with their wings and also sing. Flappet Larks were observed in northern Nigeria in July and August 1968 and in the Northern Province of Zambia in March 1972. The larks flew around slowly at heights of about 50-100 m and sometimes were barely visible while they flapped at the higher altitudes. The wings during flapping appeared to be held more stiffly out from the sides than during the normal flight. Noise from flapping carried over a few hundred meters and was as loud as or louder than the songs of some other larks that sing in flight, e.g. the Horned Lark or Shore Lake Eremophila alpestris and the Skylark Alauda arvensis. The individual flap notes are grouped into discreet bursts, and several bursts are regularly given in a flapping series that is repeated without any noticeable variation in an individual bird. The flap notes are characterised by abrupt pulses of noise that cover a wide range of frequencies (Fig. 1). The lower frequencies are the louder and the sound energy becomes progressively less at the higher frequencies. The apparent differences in the frequency spectrum of flap notes within these and the following audiospectrographs are evidently not biologically significant but rather are artifacts of the loudness of the sounds recorded and analysed on the Sonagraph, and the apparent differences in amplitude between flaps of a series may result from the changing distance and the direction of flight of the bird from the microphone. A tape recording of one individual near Zaria, Nigeria (Fig. 1 (a)) showed that each wingflap series was repeated with no visible audiospectrographic variation four times by the bird. At least two other individuals were heard flapping at Zaria, and though they were not tape recorded they were apparently identical in flapping pattern to the first with two short bursts and then a longer burst of nearly a second’s duration. The phrasing and