Checklist of marine mammal parasites in New Zealand and Australian waters

Abstract

Marine mammals are long-lived top predators with vagile lifestyles, which often inhabit remote environments. This is especially relevant in the oceanic waters around New Zealand and Australia where cetaceans and pinnipeds are considered as vulnerable and often endangered due to anthropogenic impacts on their habitat. Parasitism is ubiquitous in wildlife, and prevalence of parasitic infections as well as emerging diseases can be valuable bioindicators of the ecology and health of marine mammals. Collecting information about parasite diversity in marine mammals will provide a crucial baseline for assessing their impact on host and ecosystem ecology. New studies on marine mammals in New Zealand and Australian waters have recently added to our knowledge of parasite prevalence, life cycles and taxonomic relationships in the Australasian region, and justify a first host–parasite checklist encompassing all available data. The present checklist comprises 36 species of marine mammals, and 114 species of parasites (helminths, arthropods and protozoans). Mammal species occurring in New Zealand and Australian waters but not included in the checklist represent gaps in our knowledge. The checklist thus serves both as a guide for what information is lacking, as well as a practical resource for scientists working on the ecology and conservation of marine mammals.

Lurking in the water: testing eDNA metabarcoding as a tool for ecosystem-wide parasite detection

“…These ASVs may represent a nematode species recorded in the taxonomic survey of the lakes, which was identified to the family level within Anisakidae and found within yellow-eye mullet Aldrichetta forsteri (Supplementary Material). Alternatively, these ASVs could actually represent Contracaecum ogmorhi or O. mirounga , as these species have been recorded as parasites for New Zealand pinnipeds (Lehnert et al ., 2019; Shamsi, 2019) and New Zealand fur seals Arctocephalus forsteri are known to occasionally enter Lake Waihola.…”

Aquatic disease in New Zealand: synthesis and future directions

“…Anglade and Randhawa 2018). As parasite studies move further offshore new parasite species and lifecycles will become uncovered, elucidating ecological linkages pathways (Anglade and Randhawa 2018;Lehnert et al 2019) that can be incorporated into pelagic food web studies.…”

“…caused significant mortality of Hoiho chicks on Stewart Island (Hill 2008). Another apicomplexan parasite, Toxoplasma gondii, is an emerging parasite of marine mammals from around the world and has been reported from five marine mammal species in New Zealand (Lehnert et al 2019), most notably the Hector's dolphin Cephalorhynchus hectori where it is hypothesised to cause increased mortality rates (Roe et al 2015). An unusual reddening syndrome has been observed in IUCN red listed New Zealand lamprey Geotria australis, where it has been linked to mortalities although no cause has yet been formally identified (Brosnahan et al 2019d).…”

“…Fish parasites, like the bacterium Edwardsiella tarda, the cause of piscine septicaemia, have been reported overseas as introduced to the sea from wastewater (Mohanty and Sahoo 2007). Toxoplasma gondii is a common terrestrial parasite that uses felines as a definitive host and recently T. gondii has been identified in GLM (Coupe et al 2018) and five New Zealand marine mammals (Lehnert et al 2019), most notably Hector's dolphins (Roe et al 2013). Globally, the detection of T. gondii has sparked concerns about the role T. gondii has in the health of different aquatic animals, particularly the endangered southern sea otter (Enhydra lutris nereis) (Miller et al 2002).…”

“…Identifying non-native parasites is complicated by slow rates of parasite species descriptions (Poulin et al 2016) and poor documentation of historical natural ranges of parasites, although checklists are useful 'working inventories' of New Zealand parasites (e.g. Lehnert et al 2019). Regardless, species-rich and abundant microbial communities detected in high-risk biosecurity vectors like ship ballast water (Pagenkopp Lohan et al 2016), suggest parasite introductions is an ever-present risk that remains a large gap in biosecurity science and invasion ecology.…”