The seasonal and diel feeding habits of the goosander, Mergus merganser, the red-breasted merganser, M. serrator, gulls (Larus canus, L. argentatus and L. fuscusj and terns, Sterna hirundo/paradisaea were studied at 64V05'N. Birds' activity patterns were influenced by the nocturnal spawning of the river lamprey (Lampetra fluviatilis). Food selection and food consumption by hand-raised mergansers together with aquarium studies of the diel activity patterns of their most important prey supplemented the field data. River lamprey dominated the diet of the goosander by weight and the sculpin Cottus gobio by number. The fish consumption of the goosanders was found to be about 12% of the available river lamprey biomass and about 17% of the sculpin biomass during the breeding season. In experimental situations the river lamprey was a low- pritority species compared with salmon , Salmo salar, brown trout, 53. trutta, and minnow, Phoxinus phoxinus, when presented to satiated birds of both Mergus species. When hungry, however, the birds caught the available prey irrespective of species, but they selected larger prey when two size classes were present. Experimental results were compared with field data on availability, consumption and the escape behaviour of the various fish species. The rivers emptying in the Bothnian Bay are regarded as important feeding areas for birds breeding along the coast. In early spring they get access to abundant and reliable food resources, e.g the river lamprey. Later on the three-spined stickleback, Gasterosteus aculeatus, supply both Mergus species with food in the river and also along the coast. From the middle of June potential food supply available to birds decreases in the rivers and becomes more abundant in the coastal area. / <p>S. 1-41: sammanfattning, s. 43-227: 7 uppsatser</p> / digitalisering@umu

In Karpfen sächsischer Karpfenteichwirtschaften spielen u.a. die Zestoden Neogryporhynchus cheilancristrotus und Paradilepis scolecina und der Trematode Diplostomum pseudospathaceum eine Rolle (KAPPE 2004, PIETROCK et al. 2006, KAPPE & SEIFERT unveröff.). Weitere Fischarten (Schleie, Plötze, Regenbogenforelle) sind mit den Trematoden Diplostomum sp., Hysteromorpha triloba, Posthodiplostomum cuticola infiziert (PIETROCK et al. 2006). Mit dieser Arbeit sollte der Versuch unternommen werden, die Bedeutung Fisch fressender Vögel als Vektor Fisch pathogener Helminthen in Sachsen aufzuklären. Dafür wurden im Zeitraum von Juni 2003 bis Dezember 2004 97 Kormorane (Phalacrocorax carbo) und 46 Graureiher (Ardea cinerea) aus dem Einzugsgebiet sächsischer Teichwirtschaften auf ihren Befall mit Endohelminthen untersucht. Im Winter 2004 konnte zusätzlich ein Silberreiher (Casmerodius albus) und eine Silbermöwe (Larus argentatus) in die Untersuchungen einbezogen werden. Während des Untersuchungszeitraumes konnten so insgesamt 29 Parasitengattungen bzw. -arten nachgewiesen werden, denen z.T. kommerziell genutzte Süßwasserfische als Zwischenwirte oder paratenische Wirte dienen. Die Parasiten des Kormorans umfassten 15 verschiedene Parasitenarten. Dabei handelte es sich um die beiden Zestoden Ligula intestinalis und Paradilepis scolecina, die sechs Nematoden Baruscapillaria spp., Contracaecum rudolphii, Cyathostoma microspiculum, Desmidocercella incognita, Eucoleus contortus und Syncuaria squamata und die sieben Trematoden Clinostomum complanatum, Holostephanus dubinini, Hysteromorpha triloba, Metorchis xanthosomus, Paryphostomum radiatum, Petasiger exaeretus und P. phalacrocoracis. Außerdem wurden die zwei Kratzer Corynosoma strumosum und Polymorphus sp. nachgewiesen. Im Graureiher konnten dagegen nur neun Helminthenarten nachgewiesen werden. So der Zestode Neogryporhynchus cheilancristrotus, die sechs Trematoden Apharyngostrigea cornu, Bilharziella polonica, Diplostomum sp., Echinoasmus belocephalus, Posthodiplostomum cuticola und Tylodelphis excavata und die drei Nematoden Avioserpens galliardi, Desmidocercella incognita und Desmidocercella numidica. In der Silbermöwe konnten der Zestode Echinocotyle verschureni, die vier Trematoden Apophallus mühlingi, Diplostomum pseudospathaceum, Renicola lari und Metorchis xanthosomus sowie die drei Nematoden Desmidocercella incognita, Cosmocephalus obvelatus und Paracuaria tridentata nachgewiesen werden. Die parasitologischen Befunde des Silberreihers beschränkten sich auf Apharyngostrigea sp., Desmidocercella incognita und Desmidocercella numidica. Eine Beeinflussung der Helminthenfauna von Karpfen durch Kormoran und Reiher als auch umgekehrt konnte anhand der eigenen Untersuchungen in sächsischen Teichwirtschaften nicht sicher nachgewiesen werden. / In Saxonian carp ponds the cestodes Neogryporhynchus cheilancristrotus and Paradilepis scolecina and the trematode Diplostomum pseudospathaceum occur amongst others in carps (KAPPE 2004, PIETROCK et al. 2006, KAPPE & SEIFERT unpublished). Further fish species (tench, roach, rainbow trout) are infected with the trematodes Diplostomum sp., Hysteromorpha triloba and Posthodiplostomum cuticola (PIETROCK et al. 2006). This work was performed to analyse the importance of fish eating birds as vectors of fish pathogenic helminths. For this purpose 97 common cormorants (Phalacrocorax carbo) and 46 grey herons (Ardea cinerea) were examined on their infestation with endohelminths during the term of June 2003 to December 2004. All these birds came from the vicinity of Saxonian fish ponds. In winter 2004 additionally an egret (Casmerodius albus) and an hering gull (Larus argentatus) were included into the investigations. Altogether 29 parasite species and genus respectively could be detected. Some of these endohelminths use fresh water fishes as intermediate or paratenic hosts. The cormorants harboured 15 different parasite species and genus respectively: the two cestodes Ligula intestinalis and Paradilepis scolecina, the six nematodes Baruscapillaria carbonis, Contracaecum rudolphii, Cyathostoma microspiculum, Desmidocercella incognita, Eucoleus contortus and Syncuaria squamata and seven trematodes the Clinostomum complanatum, Holostephanus dubinini, Hysteromorpha triloba, Metorchis xanthosomus, Paryphostomum radiatum, Petasiger exaeretus and P. phalacrocoracis. In addition the two acanthocephales Corynosoma strumosum and Polymorphus sp. were detected. In the grey heron nine helminth species/genus could be detected: the cestode Neogryporhynchus cheilancristrotus, the six trematodes Apharyngostrigea cornu, Bilharziella polonica, Diplostomum sp., Echinoasmus belocephalus, Posthodiplostomum cuticola and Tylodelphis excavata and the three nematodes Avioserpens galliardi, Desmidocercella incognita and Desmidocercella numidica. In the hering gull the cestode Echinocotyle verschureni, the four trematodes Apophallus muehlingi, Diplostomum pseudospathaceum, Renicola lari and Metorchis xanthosomus as well as the three nematodes Desmidocercella incognita, Cosmocephalus obvelatus and Paracuaria tridentata were detected. Merely three endohelminths could be demonstrated in the investigated egret: Apharyngostrigea sp., Desmidocercella incognita and D. numidica. Six of the 29 endohelminth species and genus respectively were found in this examination to infest both fish and birds in Saxonian fish ponds. Nevertheless the helminth fauna of the inestigated birds, in particular of cormorants and herons did not make a definite impact on the carps´ infestation with endohelminths. As well as the fish helminth fauna were not unequivocally linked to those of the birds.

In Karpfen sächsischer Karpfenteichwirtschaften spielen u.a. die Zestoden Neogryporhynchus cheilancristrotus und Paradilepis scolecina und der Trematode Diplostomum pseudospathaceum eine Rolle (KAPPE 2004, PIETROCK et al. 2006, KAPPE & SEIFERT unveröff.). Weitere Fischarten (Schleie, Plötze, Regenbogenforelle) sind mit den Trematoden Diplostomum sp., Hysteromorpha triloba, Posthodiplostomum cuticola infiziert (PIETROCK et al. 2006). Mit dieser Arbeit sollte der Versuch unternommen werden, die Bedeutung Fisch fressender Vögel als Vektor Fisch pathogener Helminthen in Sachsen aufzuklären. Dafür wurden im Zeitraum von Juni 2003 bis Dezember 2004 97 Kormorane (Phalacrocorax carbo) und 46 Graureiher (Ardea cinerea) aus dem Einzugsgebiet sächsischer Teichwirtschaften auf ihren Befall mit Endohelminthen untersucht. Im Winter 2004 konnte zusätzlich ein Silberreiher (Casmerodius albus) und eine Silbermöwe (Larus argentatus) in die Untersuchungen einbezogen werden. Während des Untersuchungszeitraumes konnten so insgesamt 29 Parasitengattungen bzw. -arten nachgewiesen werden, denen z.T. kommerziell genutzte Süßwasserfische als Zwischenwirte oder paratenische Wirte dienen. Die Parasiten des Kormorans umfassten 15 verschiedene Parasitenarten. Dabei handelte es sich um die beiden Zestoden Ligula intestinalis und Paradilepis scolecina, die sechs Nematoden Baruscapillaria spp., Contracaecum rudolphii, Cyathostoma microspiculum, Desmidocercella incognita, Eucoleus contortus und Syncuaria squamata und die sieben Trematoden Clinostomum complanatum, Holostephanus dubinini, Hysteromorpha triloba, Metorchis xanthosomus, Paryphostomum radiatum, Petasiger exaeretus und P. phalacrocoracis. Außerdem wurden die zwei Kratzer Corynosoma strumosum und Polymorphus sp. nachgewiesen. Im Graureiher konnten dagegen nur neun Helminthenarten nachgewiesen werden. So der Zestode Neogryporhynchus cheilancristrotus, die sechs Trematoden Apharyngostrigea cornu, Bilharziella polonica, Diplostomum sp., Echinoasmus belocephalus, Posthodiplostomum cuticola und Tylodelphis excavata und die drei Nematoden Avioserpens galliardi, Desmidocercella incognita und Desmidocercella numidica. In der Silbermöwe konnten der Zestode Echinocotyle verschureni, die vier Trematoden Apophallus mühlingi, Diplostomum pseudospathaceum, Renicola lari und Metorchis xanthosomus sowie die drei Nematoden Desmidocercella incognita, Cosmocephalus obvelatus und Paracuaria tridentata nachgewiesen werden. Die parasitologischen Befunde des Silberreihers beschränkten sich auf Apharyngostrigea sp., Desmidocercella incognita und Desmidocercella numidica. Eine Beeinflussung der Helminthenfauna von Karpfen durch Kormoran und Reiher als auch umgekehrt konnte anhand der eigenen Untersuchungen in sächsischen Teichwirtschaften nicht sicher nachgewiesen werden. / In Saxonian carp ponds the cestodes Neogryporhynchus cheilancristrotus and Paradilepis scolecina and the trematode Diplostomum pseudospathaceum occur amongst others in carps (KAPPE 2004, PIETROCK et al. 2006, KAPPE & SEIFERT unpublished). Further fish species (tench, roach, rainbow trout) are infected with the trematodes Diplostomum sp., Hysteromorpha triloba and Posthodiplostomum cuticola (PIETROCK et al. 2006). This work was performed to analyse the importance of fish eating birds as vectors of fish pathogenic helminths. For this purpose 97 common cormorants (Phalacrocorax carbo) and 46 grey herons (Ardea cinerea) were examined on their infestation with endohelminths during the term of June 2003 to December 2004. All these birds came from the vicinity of Saxonian fish ponds. In winter 2004 additionally an egret (Casmerodius albus) and an hering gull (Larus argentatus) were included into the investigations. Altogether 29 parasite species and genus respectively could be detected. Some of these endohelminths use fresh water fishes as intermediate or paratenic hosts. The cormorants harboured 15 different parasite species and genus respectively: the two cestodes Ligula intestinalis and Paradilepis scolecina, the six nematodes Baruscapillaria carbonis, Contracaecum rudolphii, Cyathostoma microspiculum, Desmidocercella incognita, Eucoleus contortus and Syncuaria squamata and seven trematodes the Clinostomum complanatum, Holostephanus dubinini, Hysteromorpha triloba, Metorchis xanthosomus, Paryphostomum radiatum, Petasiger exaeretus and P. phalacrocoracis. In addition the two acanthocephales Corynosoma strumosum and Polymorphus sp. were detected. In the grey heron nine helminth species/genus could be detected: the cestode Neogryporhynchus cheilancristrotus, the six trematodes Apharyngostrigea cornu, Bilharziella polonica, Diplostomum sp., Echinoasmus belocephalus, Posthodiplostomum cuticola and Tylodelphis excavata and the three nematodes Avioserpens galliardi, Desmidocercella incognita and Desmidocercella numidica. In the hering gull the cestode Echinocotyle verschureni, the four trematodes Apophallus muehlingi, Diplostomum pseudospathaceum, Renicola lari and Metorchis xanthosomus as well as the three nematodes Desmidocercella incognita, Cosmocephalus obvelatus and Paracuaria tridentata were detected. Merely three endohelminths could be demonstrated in the investigated egret: Apharyngostrigea sp., Desmidocercella incognita and D. numidica. Six of the 29 endohelminth species and genus respectively were found in this examination to infest both fish and birds in Saxonian fish ponds. Nevertheless the helminth fauna of the inestigated birds, in particular of cormorants and herons did not make a definite impact on the carps´ infestation with endohelminths. As well as the fish helminth fauna were not unequivocally linked to those of the birds.