Beschreibung: Temperature, Salinity, pH, oxygen and chlorophyll data was collected with a Hydrolab HL7 multi parameter sonde installed on an oyster table in the Oddewatt oyster reef in Königshafen, Sylt, Germany (55.028483, 8.433876). The table and sonde surface during low tide.

Beschreibung: Temperature, Salinity, pH, oxygen and chlorophyll data was collected with a Hydrolab HL7 multi parameter sonde installed on an oyster table in the Oddewatt oyster reef in Königshafen, Sylt, Germany (55.028483, 8.433876). The table and sonde surface during low tide.

Beschreibung: In this study, we examined how chemical cues from a predatory marine crab affect the transmission of a parasitic trematode from its first (periwinkle) to its second (mussel) intermediate host. We collected the data in a laboratory experiment. Here, snails (Littorina littorea) infected with a parasite (Himasthla elongata) were kept in two different treatments (with predation risk and control). Subsequently, the excreted cercariae were collected as data. The experiments were conducted at the Wadden Sea Station of the Alfred Wegener Institute in List, Sylt, Germany. We sampled the snails at the the Danish coast of the Baltic Sea (Jütland, Arosund; 55*15'45.8'N 9*42'39.2'E). Snails had a shell height of 14-18mm corresponding to an age of two years. Infection status were screened at the laboratory. The crabs for the predation cue were sampled at the Oddewatt, List Sylt (German, Wadden Sea). Only male crabs with a size og 20-30mm catapace width were sampled. The blue mussels were sampled at the west coast of Sylt (Wenningstedt beach) were trematode infection do not occur naturally (confirmed by screening 50 mussels). Mussel shell length wars 25-30mm. Sampling of the experimental organisms: Mytilus edulis (latitude:54.937.600, longitude: 8.312.915); Littorina littorea (latitude55.262.722:longitude:9.710.889 ) and Hemigrapsus takanoi (latitude:55.028.713longitude:8.434.260 ).

Beschreibung: In this study, we examined how chemical cues from a predatory marine crab affect the transmission of a parasitic trematode from its first (periwinkle) to its second (mussel) intermediate host. We collected the data in a laboratory experiment. Here, snails (Littorina littorea) infected with a parasite (Himasthla elongata) were kept in two different treatments (with predation risk and control). Subsequently, the excreted cercariae were collected as data. The experiments were conducted at the Wadden Sea Station of the Alfred Wegener Institute in List, Sylt, Germany. We sampled the snails at the the Danish coast of the Baltic Sea (Jütland, Arosund; 55*15'45.8'N 9*42'39.2'E). Snails had a shell height of 14-18mm corresponding to an age of two years. Infection status were screened at the laboratory. The crabs for the predation cue were sampled at the Oddewatt, List Sylt (German, Wadden Sea). Only male crabs with a size og 20-30mm catapace width were sampled. The blue mussels were sampled at the west coast of Sylt (Wenningstedt beach) were trematode infection do not occur naturally (confirmed by screening 50 mussels). Mussel shell length wars 25-30mm.

Beschreibung: In this study, we examined how chemical cues from a predatory marine crab affect the transmission of a parasitic trematode from its first (periwinkle) to its second (mussel) intermediate host. We collected the data in a laboratory experiment. Here, snails (Littorina littorea) infected with a parasite (Himasthla elongata) were kept in two different treatments (with predation risk and control). Subsequently, the excreted cercariae were collected as data. The experiments were conducted at the Wadden Sea Station of the Alfred Wegener Institute in List, Sylt, Germany. We sampled the snails at the the Danish coast of the Baltic Sea (Jütland, Arosund; 55*15'45.8'N 9*42'39.2'E). Snails had a shell height of 14-18mm corresponding to an age of two years. Infection status were screened at the laboratory. The crabs for the predation cue were sampled at the Oddewatt, List Sylt (German, Wadden Sea). Only male crabs with a size og 20-30mm catapace width were sampled. The blue mussels were sampled at the west coast of Sylt (Wenningstedt beach) were trematode infection do not occur naturally (confirmed by screening 50 mussels).

Beschreibung: In this study, we examined how chemical cues from a predatory marine crab affect the transmission of a parasitic trematode from its first (periwinkle) to its second (mussel) intermediate host. We collected the data in a laboratory experiment. Here, snails (Littorina littorea) infected with a parasite (Himasthla elongata) were kept in two different treatments (with predation risk and control). Subsequently, the excreted cercariae were collected as data. The experiments were conducted at the Wadden Sea Station of the Alfred Wegener Institute in List, Sylt, Germany. We sampled the snails at the the Danish coast of the Baltic Sea (Jütland, Arosund; 55*15'45.8'N 9*42'39.2'E). Snails had a shell height of 14-18mm corresponding to an age of two years. Infection status were screened at the laboratory. The crabs for the predation cue were sampled at the Oddewatt, List Sylt (German, Wadden Sea). Only male crabs with a size og 20-30mm catapace width were sampled. The blue mussels were sampled at the west coast of Sylt (Wenningstedt beach) were trematode infection do not occur naturally (confirmed by screening 50 mussels). Mussel shell length wars 25-30mm.

Beschreibung: Temperature, Salinity, pH, oxygen and chlorophyll data was collected with a Hydrolab HL7 multi parameter sonde installed on an oyster table in the Oddewatt oyster reef in Königshafen, Sylt, Germany (55.028483, 8.433876). The table and sonde surface during low tide.

Beschreibung: Predators can affect parasite–host interactions when directly preying on hosts or their parasites. However, predators may also have non-consumptive indirect effects on parasite–host interactions when hosts adjust their behaviour or physiology in response to predator presence. In this study, we examined how chemical cues from a predatory marine crab affect the transmission of a parasitic trematode from its first (periwinkle) to its second (mussel) intermediate host. Laboratory experiments revealed that chemical cues from crabs lead to a threefold increase in the release of trematode cercariae from periwinkles as a result of increased periwinkle activity. This positive effect on transmission was contrasted by a 10-fold reduction in cercarial infection rates in the second intermediate host when we experimentally exposed mussels to cercariae and predator cues. The low infection rates were caused by a substantial reduction in mussel filtration activity in the presence of predator cues, preventing cercariae from entering the mussels. To assess the combined net effect of both processes, we conducted a transmission experiment between infected periwinkles and uninfected mussels. Infection levels of mussels in the treatments with crab cues were sevenfold lower than in mussels without crab chemical cues. This suggests that predation risk effects on mussel susceptibility can counteract the elevated parasite release from first intermediate hosts, with negative net effects on parasite transmission. These experiments highlight that predation risk effects on parasite transmission can have opposing directions at different stages of the parasite's life cycle. Such complex non-consumptive predation risk effects on parasite transmission may constitute an important indirect mechanism affecting prevalence and distribution patterns of parasites in different hosts across their life cycle.

Beschreibung: 〈jats:title〉Abstract〈/jats:title〉〈jats:p〉Phages depend on their bacterial hosts to replicate. The habitat, density and genetic diversity of host populations are therefore key factors in phage ecology, but our ability to explore their biology depends on the isolation of a diverse and representative collection of phages from different sources. Here, we compared two populations of marine bacterial hosts and their phages collected during a time series sampling program in an oyster farm. The population of 〈jats:italic〉Vibrio crassostreae〈/jats:italic〉, a species associated specifically to oysters, was genetically structured into clades of near clonal strains, leading to the isolation of closely related phages forming large modules in phage–bacterial infection networks. For 〈jats:italic〉Vibrio chagasii〈/jats:italic〉, which blooms in the water column, a lower number of closely related hosts and a higher diversity of isolated phages resulted in small modules in the phage–bacterial infection network. Over time, phage load was correlated with 〈jats:italic〉V. chagasii〈/jats:italic〉 abundance, indicating a role of host blooms in driving phage abundance. Genetic experiments further demonstrated that these phage blooms can generate epigenetic and genetic variability that can counteract host defence systems. These results highlight the importance of considering both the environmental dynamics and the genetic structure of the host when interpreting phage–bacteria networks.〈/jats:p〉