Bright idea to save penguins

PENGUINS at Melbourne Zoo could help save some of the thousands of seabirds killed in gillnets each year after a world-first study found they reacted better to different net colours.

Institute for Marine and Antarctic Studies scientists and Zoos Victoria tested different coloured nets in the zoo’s penguin pool to see if the birds were better at seeing and avoiding particular colours.

Near invisible in the water, gillnets are made from fine nylon that catches fish around the gills.

However, researchers placed panels of different coloured gillnets across the penguin pool and collected data on the number of interactions penguins had with the different treatments.

They found collision rates were lower with orange nets, with only five collisions from 91 encounters. This was compared with clear netting (33 of 92) and green netting (16 of 52).

Lead author and IMAS honours student Roshan Hanamseth said the study could be the first step towards saving thousands of birds each year due to gillnetting, which was estimated to have a higher avian mortality than for longline fishing.

“Little penguins are among several species significantly affected by gillnet fishing, so it’s great that the penguins at Melbourne Zoo could potentially be helping to save their cousins in the wild,” Mr Hanamseth said.

“While further research is needed to assess the impact of different coloured nets on target fish species, studies such as this could pave the way for an efficient and cost-effective alternative for the industry to adopt.”

A long-term international study, titled Tangled and Drowned, had found that 14 penguin species were at risk of gillnetting in the Southern Hemisphere.

One of the authors was BirdLife Tasmania convener Eric Woehler, who called for a gillnet ban in Tasmania to ensure the conservation status of little penguins.

Dr Woehler said there were about 10,000 registered gillnets in Tasmania.

“We know where the penguin colonies are, we know little penguins and other seabirds drown in gillnets, yet Tasmanian governments of both persuasions have refused to protect little penguins,” he said.

Environment Minister Elise Archer said changes to the Scalefish Fishery Management Plan in November 2015 included setting a minimum age for use of gillnets as well as requirements on time of day for setting and removal to avoid high-risk interaction.

Ms Archer said all commercial and recreational gillnets were banned at: the Macquarie Harbour entrance, Godfreys Beach at Stanley, Low Head, Lillico Beach, Musselroe Bay, Parsonage Point at Burnie, Waubs Bay at Bicheno, Sloping Island and Spectacle Island. In the Derwent River the no gillnetting boundary has been extended to Dennes Point/Cape Direction.

But Dr Woehler said while the spatial closures had been implemented, the majority of colonies were without protection from gillnets.