CONTAMINANTS IN NEW ZEALAND SEABIRD COLONIES
Seabirds are well-known vectors for the movement of beneficial nutrients from their marine feeding grounds to their terrestrial nesting sites, depositing these marine-derived nutrients (primarily nitrogen and phosphorous), via their guano, but also through other inputs such as eggs, feathers, and carcasses. The effects of large seabird colonies on terrestrial environments can be profound, where additions can create local ‘hotspots’ of biological productivity.
However, it is not just nutrients that are transported by seabirds. Inorganic (including heavy metals, Hg, Pb, etc) and organic pollutants can also be transported to land. These contaminants can come from the seabirds’ prey or from the ingestion of marine plastics. Species at higher trophic levels often contain high concentrations of organic and inorganic pollutants due to bioaccumulation and biomagnification. Sadly, the makes seabirds such as penguins, particularly useful indicators of heavy metal contamination in the environment for several reasons: they are predators occupying various niches and trophic levels, they forage both nearshore and far out at sea, and they are generally long-lived species.
We will investigate the presence of microplastics and heavy metals in the nesting areas, guano and feathers of two New Zealand seabirds species, (the declining Little penguin | Kororā; and non-threatened Australasian gannet | Tākapu). Kororā and Tākapu colonies from five geographical locations, each with varying degrees of industrialisation, will be compared to investigate whether microplastic abundance and type, and heavy metal concentrations and species; can be correlated to proximity to built-up areas. Potential sources of contaminants will also be investigated.
I will be looking for keen MSc students to participate in this research (check out my student supervision page for more information). There is potential for this research to be linked to GPS and foraging data to further provide critical insight into the life histories of persistent contaminants in seabird colonies. This research is being undertaken in collaboration with Oamaru Blue Penguin Colony, the West Coast Penguin Trust, Pohatu Penguins, and the Cape Sanctuary.