FOOD HABITS OF THE SPorrED OWLET, ATHENE BRAMA

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1 Pak. J. Agri. Sci. 27(2) 127, 1990 FOOD HABITS OF THE SPrrED OWLET, ATHENE BRAMA Mirza A. Beg, M. Maqbl & M. Mushtaq ul - Hassan Department f Zlgy & Fisheries, University f Agriculture, Falsalabad Fur hundred and twenty -ne pellets f the Sptted Owlet (Athene brama) were cllected frtnighty frm the campus f the University f Agriculture, Faisalabad frm August, 1984 t July, Examinatin f the cuticular patterns f the scales f the hairs fund in these pellets, revealed presence f 10 species f small mammals f which rats and mice were the staple items. Remanents f insects in the pellets indicated cnsumptin f members f eight rders f insects amng which clepterans and lepidpterans were predminant. The insects predminated in the spring and summer diet whereas small mammals in the fall and winter diet. INTRODUCTION Of the several resident species f wls in the Punjab, the Sptted Owlet (Athene brama) is perhaps the cmmnest. In sme lcalities almstevery grve hlds a resident pairrtw f these diminutive raptrs. It is widely distributed almst.all ver the lwlands f Pakistan. In Baluchistan and nrthward alng the Afghan frntiers, Athene brama is replaced by its cngener, Athene nctua. Athene brama is largely crepuscular and ncturnal and can ften be seen perched n fence psts and ther pints f vantage waiting patiently fr the quarry and sallying ccasinally t the grund ir its pursuit. The present study dcuments infrmatin abut the fd habits f the Sptted Owlet (Athenebrama) nthe Campusfthe University f Agriculture, Faisalabad. MATERIALS AND METHODS Fur hundred and twenty-ne pellets f the Sptted Owlet were cllected frtnightly frm the Campus f the University f Agriculture, frm August, 1984 t July, All the pellets, in each frtnightly samples, were saked in water befre being pulled apart. Bnes, hairs, feathers and fragments f insects were srted ut under the lw pwer f a bincular micrscpe. These remanents f the wlet's fd were dried and their weights and vlumes, in each f the frtnightly samples, were apprximated. Wings, legs and heads f insects in the pellets facilitated their identificatin t rder and family levels. Befre mixing the cntents f the individual pellets, three hairs were randmly taken frm each pellet, washed in warm water, cleaned in alchl and dried n a bltting paper. A thin film f cmmercial glue "Pan-fix" was made ver a slide and the hairs were placed n the film immediately thereafter. After abut tw minutes they were lifted frm ne end with the helpf frceps. Impressins f cuticular cvering fthe hairs thus frmed were examined under high pwer f a micrscpe and cmpared with reference impressins f the hairs f knwn species f small mammals. RESULTS Pellet Types: Like ther wls, the Sptted Owlet swallws its prey whle, digests the sft parts then disgrges the bnesjvrapped in hair as a cmpact pellet. The Sptted Owlets were nted t regurgitate three types f pellets. Large-sized pellets (Fig.1 a) were predminant in winter, tess in spring and fall, and least in summer samples. The prprtin f the medium sized pellets (Fig.1b) in the seasnal samples varied very little. The seasnal variatins in the abundance f srnall pellets (Fig.1c) were, hwever, inversely related t thse f the large pellets; the frmer being predminant in summer,

2 less abundant in spring and fall, and least in the winter samples. The large pellets mainly cntained hair and bnes, whereas in small pellets the prprtin f insects was relatively greater. The medium - sized pellets did nt shw evidence f seasnal predminance f any particular type f fd remanents. Fd Remanents: The pellets f the Sptted Owlet cmprised mainly small bnes, hairs, feathers and fragments f insects which cntributed 17, 28,, and 4% f the dry weight and 12, 42, 4, and 28% f the vlume f the pellets, respectively. Changes in the vlume and weight f bth hairs and bnes in the seasnal samples were inversely related t that f insect remains. The bnes and hairs had the largest vlume and weight in the winter samples, less in fall, lesser in spring, and the least in the summer samples, wheresas the vlume and weight f insect remains measured maximum in the summer, less in the spring, lesser in the fall, and the least in the winter samples. Feathers were represented in all the frtnightly samples but always in small numbers. Small Mammals: Ten species f small mammals were represented in the pellets f the Sptted Owlet (Table 1). Of these, the Indian gerbille (Tatera indica) was cnsumed mst intensively thrughutthe year. The ther abundantly cnsumed species, in rder f decreasing imprtance, were the sft-furred field rat (Rattus meltada), the bandict rat (Bandicta bengalensis), the huse shrew (Suncus murinus), the huse muse (Mus musculus) and the field muse (Mus bduga). The remaining fur species, namely, the palm squirrel (Funambu- Ius pennsntti, the huse rat (Rattus rattus), the shrt-tailed mle rat (Neskia indica) and the small Indian mngse (Herpestes aurpunctatus) were cnsumed nly sparingly but during all the fur seasns. Insects: Insects were eaten thrughut the year. As judged frm their weight (4%) and vlume (28%) in the pellets, they were the best cnsumed animals. Remains f members f eight rders f insects were represented in the pellets (Table 2). Cleptera, the mst intensively cnsumed rder, was represented by fur families, all in fairly gd numbers. Carabids and scarabids were strngly represented in all the seasnal samples excepting that f the winter in which they were lacking. The dytiscid and cccinellid beetles were cnsumed thrughut the year; the frmer was eaten intensively during winter and fall whereas the latter during winter and spring. Lepidpterans were the secnd best cnsumed insects. Their maximum cnsumptin was evidenced in the fall and summer samples. The members f the rders, Odnata, Dermptera and Hymenptera were cnsumed mderately rund the year, whereas rthpterans and hmpterans were lacking in the winter and summer samples. Ispterans were cnsumed during the summer seasn nly. DISCUSSION The data suggest that the Sptted Owlets f the present study area depended mainly n insects and mammals fr their fd; the frmer predminated in the spring and summer diets and the latter in the fall and winter diets. This tempral rise and fall f a given grup f prey in the diet f the wlet was related t its availability and preferences f the wl. A less preferred prey species may becme the main item f the diet f a predatr if the preferred species, fr sme reasn, becme scarce and difficult t capture (Klpfer, 1964). It is als pssible that a ptentially suitable prey may be present in the habitat in relatively large numbers but it may elude in the predatr by virtue f its particular mde f life. Sub-terranean species f rats like Neskia Indica and Bandicta bengalensis are less likely t fall prey t the wl than Tatera indica, Rattus meltada and Mus musculus which frage abve- 128

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4 Table 2. Frequency f ccurrence f Insect remains In the seasnal samples f pellets f the Sptted Owlet Insect taxa Frequency f ccurrence (%) Fall Winter Spring Summer Ttal (n = 6) (n = 6) (n = 6) (n = 6) (n = 24) Odnata Orthptera Dermptera lsptera Hmptera Lepidptera Cleptera Carabidae Dytiscidae Cccinellidae Scarabidae Hymenptera Frmicidae Aphidae r- 10

5 grund. Further f the latter grup, Tatera indica, which inhabits sparcely vegetated fields, is mre prne t predatin by raptrs than Rattus rattus and Mus musculus which favur denser vegetatin cver. Perhaps fr this reasn Tatera indica was eaten by the Sptted Owlet mre intensively than any f the ther mammalian preys present in the study area. Finally, the timings f fraging activity f the prey and predatr is als imprtant; Funambulus pennanti being dlurnat in its habit is less prne t fall prey t the wlet than the ncturnal preys. Occurrence f Ra1tus rattus and Herpestes aurpunctatus in the fd f the wlet is f special interest. The frmer is largely an indr dwelling species in Pakistan. It is represented in the pellets f the Sptted Owlet because the latter als hunted arund human dwellings and ther buildings f the University Campus. A fully grwn small Indian mngse is t large t a prey fr the Sptted Owlet. Intuitively, the wl must have preyed n the pups f the mngse. Taber et al. (1967) have reprted that in the Punjab the mngse is capable f prducing tw t three liters in a year and its breeding is nt cnfined t any ne seasn. Occurrence f remains f mngse in all seasnal samples f the pellets f the wlet may be taken t indicate rund the year breeding in mngse. The Little Owlet (Athene nctua) in a c Denmark (Laursen,1981) and Bulgaria (Simenv, 198) has been reprted t feed mainly n small mammals. Accrding t Ali and Ripley (198) the Sptted Owlet (Athene brama) in Ind - Pak subcntinent has a predilectin fr insects, mice, small birds and lizards. Thus, the results f this ivestigatin are generally in agreement with thse f the abve cited studies. In the present study area the Sptted Owlet has established itself well in the agrecsystem f the Punjab. It ccurs there in fairly gd numbers and, in fact, may be regarded as ne f the cmmnest raptrs f the Punjab. Thus, n accunt f its numerical superirity and natural appetite fr insects and small mammals, the Sptted Iet must be playing an imprtant rle in inhibiting insect and murid rdent ppulatins living in the crplands. REFERENCES Ali, S. and S.D. Ripley.198. Handbk f The Birds f India and Pakistan, Oxfrd University Press, UK. Klpfer, P. H Behaviural Aspects f Eclgy. Princetin-Hall f India, New Delhi. Laursen, J.T Prey f the Little Owl (Athene nctua). in East Jutland (Denmark). Dan. Ornithl. Fren. Tidsskr., 75 (/4) ; Rberts, T.J., The Mammals f Pakistan, Ernest Benn Ltd., Lndn, U.K. Simenv, S.D New data n the diet f the little Owl (Athene nctua) in Bulgaria. Eklgiya (Sfia), 9(11): Taber, R. D., Sheri, A. N. and Ahmad, M.S Mammals f Lyallpur Regin, West Pakistan, J. Mamm. 48: Fig. 1. Three types f pellets disgrged by the Sptted Owlet (Athene brama) 11

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