By Dr Rachael Aderman
Wildlife Management Branch – Marine Conservation Program DPIPWE
The shy albatross breeds nowhere else in the world apart from three tiny islands in Tasmania—Albatross Island in the north and Pedra Branca (pictured) and the Mewstone in the south. Unlike many of the other albatross species that travel widely across the Southern Oceans, most of the shy albatross population remains year-round within the south-east Australian shelf waters. They are truly Australia’s own.
The total population is estimated to be around 15, 000 annual breeding pairs. Like the other 21 albatross species around the world, the shy albatross is of high conservation concern. Albatross are very slow to mature and they have a very low reproductive rate. This means that even a slight increase in mortality or reduced chance of successful breeding, may have significant consequences for the persistence of a population.
Many of the threats to the shy albatross are encountered while the birds are foraging at sea and include marine pollution and plastics ingestion; fisheries interactions; competition with fisheries or reliance on discards; and a changing ocean environment driven by climate change which is altering the type, distribution and availability of food sources.
Central to understanding the nature and consequence of these threats is knowing where shy albatross are foraging; what they are eating; and is their diet changing over time?
Researchers from the Tasmanian State Government have been monitoring the shy albatross populations for over thirty years; however, studies of their diet have been limited. Traditionally, the only way to sample their diet is to force the birds to vomit up their most recent meal. This method not only invasive but can also bias the data, as often only the hard parts—such as squid beaks— can be identified.
Now there is a powerful new tool available. DNA analysis of albatross scats (aka poo) allows researchers to identify all the food sources they have recently consumed and in what relative proportions.
Researchers have spent endless days watching shy albatross on their nests on Albatross Island in Bass Strait—waiting for the distinctive sound of an albatross relieving itself – before darting in to collect a tiny precious sample of poo in a vial. Thanks to funding from the Fisheries Research and Development Corporations (FRDC), the Australian Fisheries Management Authority (AFMA) and the Tasmanian Albatross Fund, researchers from the Marine Conservation Program of the Tasmanian State Government, in collaboration with CSIRO, are now analysing hundreds of diet samples collected over the past four years.
Key to the success of this project is ensuring that researchers have reference DNA sequences for all potential species the shy albatross could consume.
While we have managed to find samples from most of their likely food sources, DNA sequences from some key species of fish are still missing. SETFIA has kindly offered to help supply samples to fill these gaps. In coming weeks, we will be circulating to SETFIA fishers our ’most wanted’ list, complete with mug-shots and a how-to-guide. With your help, we hope to be able to create a complete picture of the diet of this incredible species.
[FRDC project 2016-118: Using scat DNA to inform sustainable fisheries management and Ecological Risk Assessments: a Shy Albatross case study]