Conference Agenda

Marine mammals are long-lived apex predators that integrate ecological signals across their ocean habitat. Their diverse and often still cryptic parasite fauna reflects their evolutionary history, adaptations and trophic links in marine ecosystems. Gastro-intestinal helminths, respiratory nematodes and arthropod parasites are frequently found in harbour and grey seals as well as harbour porpoises of the North and Baltic Sea. As opportunistic hunters, they consume diverse fish species and are exposed to trophically transmitted gastro-intestinal helminths with complex life cycles involving invertebrate and fish hosts. Variation in parasite infection patterns reflect differences in diet, host immune traits, and environmental conditions that influence parasite life cycles. Given the zoonotic potential of some helminths, species identification and monitoring their epidemiology in marine food webs is critical within a One Health framework. The respiratory tract of marine mammals is crucial to enable efficient oxygen exchange in diving animals. Lung nematodes belonging to the Metastrongyloidea are among the most pathogenic parasites in odontocetes and seals and can cause severe pathology and mortality. Little is known about parasite fauna of orcas. The first record of lungworms occurred in neonate killer whales and indicated a direct transmission and a new pseudaliid species in orcas. Arthropod parasites in marine mammals have developed unique traits to adapt to the marine environment and their vagile marine mammal hosts over long evolutionary time scales. Seal lice and nasal mites are directly transmitted between their hosts and reflect social interactions and population dynamics of their hosts. Marine mammal parasites can serve as valuable bio indicators for wildlife health and host ecology. Understanding host parasite interactions in marine wildlife is essential for assessing epidemiology of infectious pathogens, biodiversity conservation, and ecosystem resilience under ongoing environmental change.