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We conducted a carrion succession study within a restricted urban backyard in the city of Vienna, Austria (16 degrees 22'E, 48 degrees 12'N) from May to November 2001 to analyze sequence and composition of the local carrion visiting fauna. Two medium sized clothed domestic pig carcasses (Sus scrofa Linnaeus), were used as surrogate human models. In total, 42 arthropod species from the families Calliphoridae, Sarcophagidae, Sepsidae, Piophilidae, Muscidae, Fanniidae, Sphaeroceridae, Phoridae, Drosophilidae, Anthomyiidae, and Lauxaniidae (Diptera), Formicidae, Braconidae, Pteromalidae, and Vespidae (Hymenoptera), Silphidae, Staphylinidae, Histeridae, Cleridae, and Dermestidae (Coleoptera), as well as species from the orders Isopoda and Acari were collected during the decomposition of these carcasses. A significant feature in this study was the high abundance of Calliphora vomitoria (L.) and Chrysomya albiceps (Wiedemann). In the experiment conducted May to June, larvae and adults of C. vomitoria outnumbered all other blow fly species, followed by Protophormia terraenovae (Robineau-Desvoidy), C. vicina Robineau-Desvoidy, and Lucilia sericata (Meigen). C. vomitoria is generally considered to be rural in distribution, where it prefers shaded locations. The presence of this species in rural as well as in urban habitats in Austria precludes this species as biogeographic indicator. In the study beginning in August large numbers of female adults of the nonindigeous blow fly C. albiceps began oviposition at day 3 after placement of the cadaver. The predatory second and third instars of C. albiceps larvae subsequently almost monopolized the cadaver. C. albiceps is generally described as tropical and subtropical species. The observed northward expansion of its range beyond southern Europe obviously decreases the value of C. albiceps in estimating place of death, in that it is no longer exclusive to southern regions. Our results clearly show, that caution must be used when drawing conclusions from succession data generated in different geographic areas. Moreover, this study demonstrates, that arthropod mediated decomposition of a 44 kg exposed pig carcass in a central European urban habitat can be completed within 3 wk.

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During the summer months of the year 2001, six forensic cases (one is reported in the present paper), a pig carrion study in the city of Vienna (latitude 48°12'N, longitude 16°22'E) and several liver-baited traps north of Vienna, yielded large numbers of maggots of the blowfly Chrysomya albiceps (Wiedemann) (Diptera: Calliphoridae). Apart from some records from France, reports of C. albiceps from the palearctic region north of the Alps (i.e. north of a latitude of 48°N) have been scarce. Our findings provided an opportunity to derive developmental schedules for C. albiceps at five different constant temperatures (15, 20, 25, 30, 35°C). The minimal duration of development from oviposition to adult was inversely related to temperature, ranging from 8.3 ± 0.5 days at 35°C to 19.2 ± 0.92 days at 20°C. Although eggs hatched after 1.9 ± 0.16 days at 15°C, larvae did not complete development and frequently died during the first instar stage. We also found a high mortality rate (up to 99%) of native L. sericata larvae caused by predation of C. albiceps larvae under laboratory conditions, indicating a high susceptibility of L. sericata to attack by C. albiceps. Apart from this, the current and possible future distribution of C. albiceps in Europe is discussed. The northward expansion of its range beyond southern Europe obviously decreases the value of C. albiceps in estimating the site of death, in that it is no longer exclusive to southern European regions. Moreover, the aggressive feeding behaviour of second and third instar larve of C. albiceps could reset the post-mortem insect clock by clearing a corpse of all earlier arrivers.