Dear list members, The following publications have been made available for download lately: Loos, P., Cooke, J.G., Deimer, P., Fietz, K., Hennig, V., Schütte, H.J. (2010) Opportunistic sightings of harbour porpoises in the Baltic Sea at large – Kattegat, Belt Sea, Sound, Western Baltic and Baltic Proper. AC17/Doc.5-05(P). ASCOBANS, Bonn è http://www.service-board.de/ascobans_neu/files/ac17/AC17_5-05_OpportunisticS ightingsHarbourPorpoisesBalticSea.pdf Loos, P. (2009) Opportunistic sightings of harbour porpoises in the Baltic Sea at large – Kattegat, Belt Sea, Sound, Western Baltic and Baltic Proper. Bachelor thesis, University of Hamburg, Germany è http://gsm-ev.de/en/veroffentlichungen/ ABSTRACT: In order to supplement current knowledge on trends in harbour porpoise (Phocoena phocoena) occurrence, incidental sightings of harbour porpoises have been collected in the Baltic Sea. During the seasons 2003 - 2008 a total number of 5561 sightings were collected and saved for further analysis. Seasonal variation of harbour porpoise sightings, group size and group composition were examined. Sightings with juveniles (n = 539) were of special interest and were therefore analysed separately. Possible calving and nursing grounds (proposed by Koschinski, 2002) have been mapped together with all juvenile sightings in order to see if there are any notable clusters of juvenile sightings within these (or other) areas. To investigate seasonal and spatial trends in porpoise densities, sightings were divided into five different geographical and five different temporal subsets. Corresponding indices of relative density were computed using an adaptation of an effort correction method, described by Cooke (1984). Obtained results indicate that the seasonal distribution of porpoise sightings largely reflects the activity patterns of water sports enthusiasts. The group size was relatively small as in most sightings one single individual was observed. Very few reports refer to sightings of more than five individuals. Sightings with juveniles were found in nearly all proposed calving and nursing grounds, and three additional areas with a cluster of juvenile sightings could be identified. Harbour porpoise densities were found to severely decline from (north-) west to (south-) east in the western Baltic Sea. A seasonal variation in porpoise densities was detected at the end of summer with dropping densities in August and September. The study shows that incidental sightings of non-professional observers do have scientific value and provide data for various analyses concerning porpoise distribution, occurrence, and density. KEY WORDS: Harbour porpoise × Incidental sightings × Relative density × Distribution ******************************************** Philip Loos Society for the Conservation of Marine Mammals (GSM) ploos@gsm-ev.de , www.gsm-ev.de