Almost half of New Zealanders feed birds, but what's the best and safest way to attract and nourish our precious native species?
Auckland academic Daria Erastova investigated the effects of backyard sugar water on native birds for her PhD.
She tells Jesse Mulligan that although the simple concoction isn't as nutritious as flower nectar, it's a great 'supplemental' food to offer during the winter months.
A tūī feeding Photo: © Shellie Evans
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Academic and conservationist Daria Erastova Photo: Jeremy Painting
While the bread, seeds and grain that most New Zealanders feed to birds in their backyard appeal to non-native species, Daria says, native birds won't benefit from these and you may attract some unwanted visitors.
"Not every grain of bread will be picked up by birds, there will be some left over. And late at night, mice and rats will come over and help themselves. Those are the visitors most people won't be happy to see around."
The natural diet of native garden birds is flower nectar, fruit, leaves, insects, and spiders, and over summer, when these foods are abundant, it's not necessary to offer a feeding station with sugar water.
Yet in the winter months, when these foods are less available, sugar water can be a good 'supplemental' food to feed them.
Sugar water that's really sweet - 1 cup of sugar per 1 litre of water - is shown to be most beneficial for native birds, although it's lacking the nutrients as flower nectar.
"Sugar water is junk food for birds, so instead you may want to consider planting native trees which will produce natural flower nectar, berries, and leaves for them. Also, plants give shelter for insects that are a very important part of their diet."
Not only does sugar water specifically attract native species, but it's much better food for them than bread or seeds and also safer for them and us, especially when delivered in a commercial sugar-water dispenser designed to keep out non-natives.
An open dish of sugar water attracts starlings and sparrows and miners, which can pass nasty diseases to native birds and also humans.
Urban ecologist Josie Galbraith's discovery of salmonella bacteria in birds that visit backyard feeders and the feeders themselves is concerning, Daria says.
To safeguard the health of native birds and nearby humans, it's important to regularly clean your bird feeding station.
She recommends giving it a scrub with hot water - and without harsh chemicals - at least twice a week.