85 Acrocephalus 27 (128-129): 83−93, 2006 (Figure 1). I made a small experiment and placed a predator dummy, a stuffed Tawny Owl Strix aluco, to see if mobbing or predator-induced behaviour would prevail over social or territorial behaviour as known in some other bird species, e.g. Arabian Babbler Turdoides squamiceps (Sommer & Mundry 2005). At the beginning, the territorial Blackbird inspected the dummy, but later continued with attacks on its own image. When the mirror was removed, the bird came back several times to search for the “intruder”. The search lasted for approximately 15 minutes, and then the male engaged in singing or vocal display. The case shows that the territoriality in mating season can induce, at least in some males, strong agonistic reaction to intraspecific intruders. There is a question, however, whether this is a general phenomenon or is just restricted to some more aggressive or young males establishing their territories. Povzetek Opazovanje drugoletnega teritorialnega samca kosa Turdus merula, ki je 17.4.2006 v zaselku Hrastje pri Modra`ah (UTM WM53, SV Slovenija) silovito napadal lastno podobo v ogledalu. Z agresivnim vedenjem ni prenehal niti tedaj, ko mu je bila nastavljena lutka plenilca, naga~ena lesna sova Strix aluco. Napadati je nehal {ele po odstranitvi ogledala. Primer ka`e na mo~ne agresivne odzive teritorianih samcev v gnezditveni sezoni, zato bi bilo v prihodnje koristno preveriti, ali se pojav ka`e le pri nekaterih osebkih ali gre za splo{en pojav. References Catchpole, C.K. & Slater, P.J.B. (1995): Bird Song. – Cambridge University Press, Cambridge. Gill, F.B. (1995): Ornithology. – W.H. Freeman and Company, New York. Sommer, C. & Mundry, R. (2005): Do social rank and predator type influence the structure of predator-induced calls in Arabian babblers? pp. 30 In: Trilar, T. (ed.): XX. Congress of International BioAcoustic Council (IBAC), Book of Abstracts. – Prirodslovni muzej Slovenije, Ljubljana. Arrived / Prispelo: 19.4.2006 Accepted / Sprejeto: 5.10.2006 The Neretva delta region has probably played an important part in the expansion of the Spanish Sparrow, as this was the source area from where these birds colonized north Dalmatia and the islands further away in the late 1970’s (Luka~ 2004). Relying on his own data and literature reports on only 353 known nests in South Dalmatia, Luka~ (2004) estimates the amount of Spanish Sparrows breeding in the region at around 3,500 − 19,000. As there is little information about Spanish Sparrows breeding in the Neretva delta (Kralj 1996), it is important to publish as much data about the number of breeding pairs as possible. Between 3 − 10 Apr 2006, we travelled several times from Metkovi} to Lake Kuti. Along the 11 km long road between Bijeli Vir and Kuti, a total of 263 Spanish Sparrow nests were counted (no nests were found in Dubravica and Kosa). The distribution of the nests was as follows: in Bijeli Vir (YH16) 186 nests in 21 poplar trees Populus sp., and 2 in 1 willow Salix sp. In Mlini{te (YH16) 21 in 1 plane tree Platanus sp., 14 in 1 mulberry tree Morus sp., and 28 in 4 willows. In single poplars in Mislina (YH16), Bad`ula (YH16, YH15) and Kuti (YH15), 2, 7 and 3 nests were found, respectively. The number of these nests (263) provides information on the breeding period of the previous year (2005). In case some of the breeding pairs built new nests for the second clutch, that meant somewhat less pairs. However, it is not known how many of the nests were lost during the winter, and how many of the nests were overlooked by the observers. Also, a certain number of nests inside the colonies might have been used by other sparrow species (Passer domesticus, The number of Spanish Sparrow Passer hispaniolensis nests in the Neretva delta (S Dalmatia, Croatia) [tevilo gnezd travni{kega vrabca Passer hispaniolensis v delti Neretve (J Dalmacija, Hrva{ka) Jasmina Mu`ini}1 & JenŐ J. Purger2 1 Institute for Ornithology CASA, Gunduli}eva 24, HR−10000 Zagreb, Croatia, e−mail: jasmina@hazu.hr 2 University of Pécs, Institute of Biology, Ifjúság útja 6, H−7624 Pécs, Hungary, e−mail: purger@ttk. pte.hu 86 P. montanus). The number of Spanish Sparrows that may breed in the area seems to be a realistic figure. Any deviation in the survey result could be eliminated by repeating the counts both in the breeding season and after the leaves have fallen away. Povzetek Avtorja sta napravila popis travni{kih vrabcev Passer hispaniolensis v delti Neretve (J Dalmacija, Hrva{ka) na osnovi {tetja gnezd v aprilu 2006. Skupno {tevilo gnezd je bilo 263. References Kralj, J. (1996): Povijesni pregled pti~jeg svijeta podru~ja donjeg toka rijeke Neretve: rezultati istra`ivanja od 1817 – 1988. – Hrvatsko ornitolo{ko dru{tvo, Zagreb. Luka~, G. (2004): About the widening of the range and the status of the Spanish Sparrow (Passer hispaniolensis) in Croatia at the beginning of the 21th century. – Pakleni~ki zbornik 2: 113–122. Arrived / Prispelo: 17.8.2006 Accepted / Sprejeto: 5.10.2006 Nova opazovanja selitve ujed na Volovji rebri (J Slovenija) New observations of birds of prey migrating over Volovja reber (S Slovenia) Toma` Miheli~1 & Igor Brajnik2 1 DOPPS, pp 2990, SI−1001, Ljubljana, Slovenija, e−mail: tomaz.mihelic@dopps−drustvo.si 2 DOPPS, pp 2990, SI−1001, Ljubljana, Slovenija, e−mail: igor.brajnik@dopps−drustvo.si Ujede se med selitvijo pogosto odzivajo na topografijo, kar se ka`e v ve~jem koncentriranju teh ptic vzdol` gorskih grebenov in prelazov (Haugh 1972). V sklopu raziskav selitve ujed v Sloveniji je bilo v jeseni 2006 organizirano opazovanje na ve~ lokacijah po Sloveniji. Opazovanja so se za~ela konec avgusta in `e prvi dan opazovanja so se na Volovji rebri (UTM VL44) pokazali zanimivi rezultati. Selitev ujed na Volovji rebri smo opazovali 29.8.2006 med 7.30 in 15.00 h. Pono~i je de`evalo po vsej Sloveniji, zjutraj pa se je v zahodni Sloveniji razjasnilo. Meja med obla~nostjo na vzhodu in jasnino na zahodu je bila prek celotnega opazovalnega dne nad to~ko opazovanja. Na obmo~ju je nad tlemi pihal srednje mo~an SV veter, zra~ne mase pa so se sode~ po oblakih `e kakih 100 − 200 m nad temi premikale v nasprotni smeri. Selitev sva ve~ino ~asa opazovala dva opazovalca na grebenu med Veliko Milanjo (1099 m) in Devinom (1088 m). Za opazovanje sva uporabljala daljnoglede s karakteristikami 7 × 42 in 19 × 42, ter teleskopa 20 − 60 × 80 ter {irokokotni 30 × 80. Ob prihodu na opazovalno to~ko sta z vrha Lunjevice (1014 m) zletela dva beloglava jastreba Gyps fulvus, ki sta tu verjetno preno~evala, saj je bila Lunjevica v tem ~asu {e v megli oz. oblakih. Jastreba sta sedela na boru in odletela proti SZ. Grebenu sta se spet pribli`ala nad Belimi ovcami (1030 m) in do Milanke (948 m) letela okrog 50 m nad grebenom. Naj{tevil~nej{a vrsta znotraj ~asa opazovanja je bil rjavi lunj Circus aeruginosus. Prvi osebek je preletel obmo~je ob 8.15, zadnji pa ob 11.01. Lunji so preletavali obmo~je posami~ ali v skupinah do max. 5 osebkov. Skupaj je bilo opazovanih 22 rjavih lunjev. Lunji so {ir{e obmo~je Volovje rebri preletavali v dveh zgostitvah. Devet jih je preletelo greben med Belimi ovcami in Milanko, ter nadaljevali let v smeri JZ. Greben so preleteli v pasu med 10 in 100 metri nad tlemi. Druga zgostitev rjavih lunjev, po kateri je Kratki prispevki / Short Communications