FOLIA HISTORICO NATURALIA MUSEI MATRAENSIS 1996 21:5-282 TO MAY MASTER DÉNES JÁNOSSY ON HIS 70th BIRTHDAY The Comparative Osteomorphological Study of the European Small-statured Falcons (Aves: Falconidae) BÉLA SOLTI ABSTRACT: [The comparative osteomorphological study of European small-statured Falcons (Aves: Falconidae).] The author have completed the comparative osteomorphological study of smaller European Falcons, namely the Hobby (Falco subbuteo L., 1758), Merlin (Falco columbarius L., 1758), Eleonora's Falcon (Falco eleonorae Géné, 1839), Kestrel (Falco tinnunculus L., 1758), Red-footed Falcon (Falco vespertinus L., 1766) and the Lesser Kestrel {Falco naumanni Fleisch., 1818) on the basis of 187 complete or partial skeletons. This study deals with all the important bones except the ribs and the backbones, even the digits are included. From every bone 3 to 10 measurements were taken, and the minimum and maximum values, averages, variances, variant coefficients, sum of squares are given according to the sexes. From the data the ratios yielding the greatest difference are calculated, which are characteristic to the given species, and hence are useful in the identification of the species. The interspecific size and form differences are demonstrated with figures, scatter diagrams and drawings. INTRODUCTION (LITERATURE SURVEY) The osteological work up of European Falcons is already partially completed. There is a scattered earlier appearance of data on this topic in the literature, then OTTO (1981) and SCHMIDT-BURGER (1982) studied the medium-sized Central European Accipitridae, while SOLTI (1980, 1981a, 1981b) studied the bigger European Falcons in detail. In this work I completed the osteomorphological comparison of the smaller European True Falcons and Kestrels, namely the Hobby {Falco subbuteo L., 1758), Merlin {Falco columbarius L., 1758), Eleonora's Falcon {Falco eleonorae Géné, 1839), Kestrel {Falco tinnunculus L., 1758), Red-footed Falcon {Falco vespertinus L., 1766) and Lesser Kestrel {Falco naumanni Fleisch., 1818). This work - with the exception of vertebrae and costae - deals with all the important bones (including the phalanges). My aim was to demonstrate the interspecific osteological differences both in size and shape, and hence give a firmer basis for the identification of these species. In the literature d'ALTON (1838) was the first to deal with the osteology of Falcons. From the smaller European Falcons he dealt with F. subbuteo and F. tinnunculus and he compared these species with species living on other continents. He found the Hobby very similar to the greater true Falcons, only it is a bit smaller. The Kestrel specimen that he examined was a very young not yet completely ossified animal. He did not give measurements, he gave detailed drawings about the cranium, and in the case of the Kestrel also about the sternum. SUSHKIN (1899) examined the cranium of F. tinnunculus at different developmental stages, and prepared very detailed exact drawings on them. PYCRAFT (1902) examined the Falconiformes to genus level, but gave not measurements. SUSHKIN (1905) deals with the birds of prey on the basis of systematics and developmental biology, and compares the different genera of the continents. He summarises the osteological characteristics of the genera and families very thoroughly. From among the species I deal with in this study he mainly studied F subbuteo and F. tinnunculus, but he also mentions some osteological characteristic of F. columbarius and F. vespertinus. He already mentioned several 5 osteological characteristics of Falcons, such as the longitudinal rib of the palatal part of os premaxillare, the differences of the shape of the cranial part of sternum, the different forms of crista medialis hypotarsi of the tarsometatarsus, etc. These features are also demonstrated with drawings. The main measurements of several species, and among them those of the species examined by the author are also given. In the case of the limbs only the longitudinal measurements are given, which was based only on a single specimen of each species. These measurements are in accordance with the averages of my data. LAMB RECHT (1914) deals with the carpometacarpus. He gives the characteristic of the ordos, within the Falconiformes he describes among others the shape of the carpometacarpus of the Falco and Cerchneis genera. ENGELMANN (1928) publishes only photographs of sternums among others from Kestrel, Hobby and Lesser Kestrel that are interesting from the point of view of osteology. RICHARDSON (1972) gives the length of the femur of F tinnunculus and F. columbarius. BÄHRMANN (1974) deals with the Kestrel from among the lesser Falcons. In the case of the sternum he measured a great number of individuals, and gives several measurements, in the case of the coracoideum and scapula he only measured the length of a few specimens. The measured big sample of sternums gives a smaller minimum and greater maximum values than my measurements, and hence yields higher percentage of standard deviation values. ACKNOWLEDGEMENTS The measured skeletons used for this study belong to several different museums and research institutes. I would like to thank for lending and permitting to work on their material to D. Jánossy (Hungarian Natural History Museum, Budapest), E. Ählander (Swedish Natural History Museum, Stockholm), J. Boessneck (Palaeoanatomy Institute, Munich), T. Balázs (collector, Hevesvezekény), Z. Bochenski (Zoological Institute of the Polish Academy of Science, Krakow), I. S. Darewsky (Zoological Institute of the Russian Academy of Science, St. Petersburg), H. Schifter (Natural History Museum, Wien), L. Kordos (Hungarian Geological Institute, Budapest). I would also like to express my special thanks to D. Jánossy for measuring the material of the British Museum corresponding to my research for me, and for helping my research continuously. Finally I would like to thank G. Bánkuti for developing a computer programme that enabled me to calculate the standard deviation values, T. Fuisz for translating this work into english, and K. Bánkuti for his valuable help in editing. MATERIAL The collection of the measured material took quite a long time as some of them must have been borrowed from foreign museums and research institutes. From Hungarian collections the following bones were received: Hungarian Natural History Museum (Budapest): 33 skeletons, Mátra Museum (Gyöngyös) 64 skeletons, From the private collection of Tibor Balázs (Hevesvezekény) 15 skeletons, from the Hungarian National Geological Institute (Budapest) 1 skeleton. The rest of the material belongs to foreign institutes. The majority of foreign material, 32 skeletons arrived from the Swedish Natural History Museum (Stockholm). The Palaeoanatomical Institute of the Ludwig - Maximilian University (Munich) lent 19 skeletons. The Zoological Institute of the Polish Academy of Science (Krakow) lent 9 skeletons, the British Museum (London) lent 7 skeletons, the Zoological Institute of the Russian Academy of Science (St. Petersburg) lent 6 skeletons and the Natural History Museum (Wien) lent 1 skeleton. 6 The species composition of the measured material is given in the next table. F.subb. F.col. F.eleon. F.tinn. F.vesp. F.naum. Sum HNHM, Budapest 3 4 _ 16 10 _ 33 MM, Gyöngyös 3 2 - 35 24 - 64 Priv. coll., Hevesvezekény - - - 12 3 - 15 HNGI, Budapest - - - 1 - - 1 SNHM, Stockholm 6 26 - - - - 32 PI, Munich 10 3 2 - - 4 19 Zl,Krakow 5 1 - 3 - - 9 BM, London - 4 1 - - 2 7 ZI, St'Petersburg 2 4 - - - - 6 NHM, Wien - - - - - 1 1 Sum 29 44 3 67 37 7 187 From the 6 European smaller Falcons a total of 187 complete or partial skeletons were studied. It would have been desirable to carry out these investigations on a larger material, but it was impossible due to practical reasons. A larger material would possibly have altered the minimum and maximum values, but I believe that the averages would not have been altered considerably. The following table shows the composition of the material according to the species and sex. d ? ? Sum F. subbuteo 14 12 3 29 F. columbarius 18 22 4 44 F. eleonorae 1 - 2 3 F. tinnunculus 23 28 16 67 F. vespertinus 11 16 10 37 F. naumanni 4 2 1 7 Sum 71 80 36 187 The number of more important bones according to species and sex. F.subb. F.col. F.eleon. F.tinn. F.vesp. F.naum. 6 10 14 14 9 2 Cranium ? 8 19 - 22 12 1 ? - 4 1 12 6 - 6 10 14 _ 14 9 1 Mandibula ? 6 20 - 23 13 1 ? - 3 - 12 5 - 6 14 15 1 21 11 3 Coracoideum ? 11 20 - 27 13 2 . ? 3 2 2 16 10 1 6 14 16 1 21 11 3 Scapula ? 11 21 - 27 13 2 7 3 2 1 16 9 1 6 12 16 _ 17 10 3 Humerus ? 8 21 - 25 15 - ? - 2 1 15 7 2 7 F.subb. F.col. F.eleon. F.tinn. F.vesp. Fnaum. d 11 16 _ 17 10 2 Ulna ? 7 21 - 25 14 1 7 - 2 1 15 7 2 d 11 17 _ 14 10 2 Carpometacarpus ? 7 21 - 25 14 1 ? - 2 - 14 7 1 d 14 15 1 22 11 3 Sternum ? 10 21 - 23 13 2 ? 3 2 2 16 7 1 d 14 16 1 20 11 2 Pelvis ? 11 20 - 28 12 - 2 7 2 2 2 14 6 1 d 13 16 1 21 11 3 Femur ? 11 21 - 26 14 2 ? - 2 2 15 7 1 d 11 16 _ 13 9 2 Tibiotarsus ? 6 20 - 25 14 1 7 - 2 1 14 8 1 d 11 17 _ 14 10 2 Tarsometatarsus ? 7 20 - 25 14 1 7 - 2 - 13 7 1 The localities of the material is very varied. The Hobby skeletons originated from North and Central Europe. More than half of the Merlin skeletons belong to the Swedish Natural History Museum, and hence their localities are North European, and mostly Scandinavian. The rest is mainly Central European, but some specimens originate from Great Britain, Greece, and from the neighbourhood of St.