A rare white heron, or kotuku, was spotted on Glenavy farmland last week by Oamaru photographer Brenda Meuli. Oamaru Mail editor Rebecca Ryan asks Department of Conservation ranger Tom Waterhouse some questions about the native bird’s sighting in the Waimate district.
Q How common is it to see white heron (kotuku) in the Waimate and Waitaki districts?
It is relatively uncommon, but at this time of year it is normal to have one or two turn up in the region. The State Highway 1 Waitaki River bridge does seem to be a favourite spot when they do turn up. They’ve been spotted there a couple of times in the past few years – either upstream of the bridge, or roosting on the adjacent rail bridge. Other places where they’ve been seen include the Katiki Beach reservoir, the Kakanui River and the Shag River estuary.
Q Where are they usually found?
The only New Zealand breeding colony is on the West Coast, just north of Okarito Lagoon in Westland.
Q What attracts them to this area?
They need shallow water to feed in and, with some quite large lagoons nearby, there is plenty of habitat. All Day Bay, Wainono and Washdyke lagoons are all perfect places for a hungry heron. Their diet is based on whitebait during the breeding season and then other small fish, frogs, skinks, insects and even small birds. One kotuku a few years ago gained a reputation for eating silvereyes at a bird feeder in Temuka.
Q Are we likely to see them here again?
Yes, once the breeding season (September to January) has finished, they do disperse around New Zealand so there’s always a chance one will pop up on an estuary or wetland in the area.
Q How can you tell them apart from other white wading birds?
The kotuku is the largest of the white egret species you are likely to see in New Zealand. They have a yellow bill, long dark legs and a very long neck. The only other white wader of similar size is the royal spoonbill which as the name suggests, has a spoon for a bill.
Q Can you tell if the photographed bird is male or female, and how old it is?
It’s almost impossible to tell the difference or the age from the photo. Behaviour during the breeding season would be one way to distinguish between the sexes.
Q The Doc website says they have gained “almost mythical status” in New Zealand – why is that?
As the kotuku is both rare and beautiful, it has held an important place in Maori myth and folklore, as well as being revered for its white feathers. Being a large, solitary feeder with such striking plumage may have added to this and the fact that they only breed in one isolated location on the West Coast.