Birds of the Milford Track
By Nick Allen
For a track that traverses a wide range in altitude most bush bird species that can be encountered along the Milford Track largely stay surprisingly constant. The Rifleman is New Zealand’s smallest bird, only 7-9 cm from beak tip to tail tip. It’s high-pitched calls are often inaudible to older people and it flits among lower vegetation or climbs up and along moss-covered tree branches in search of insects and spiders. Kaka are also found throughout the length of the track and are large bush parrots with a variety of grating and liquid calls. Tomtits are small robins that often perch half way up tree trunks waiting for an insect to move. The black and white males are very striking. Bellbirds and Tui are both nectar feeders with pleasant songs. The Bellbird has bell-like and fluty notes in its song, the Tui is more of an improvisor and can’t resist adding clicks and wheezes to its repertoire. Blue Ducks, a blue-grey duck with a leathery beak appendage, found mostly on swift-flowing rivers is found on the Clinton River, Roaring Burn and Arthur River. There is apparently a reasonable population due to long-term trapping of their main predator the stoat, but they are difficult to see as they mostly feed at the ends of the day and good views of the rivers are few and far between. The Weka is a streaky, brown flightless rail that looks like a kiwi, but without the long beak. It is an opportunistic thief and it is a good idea not to leave food or anything shiny around as they will be carried off into the densest part of the bush in seconds. Spacing calls ‘weka, weka, weka…’ are uttered, especially around dusk so the birds know where their neighbours are. The calls are the opposite way round to the otherwise similar male kiwi calls.
The forest on the east side of the pass is dryer and has a lesser diversity of plants compared to the west. This lack of diversity has probably made life more difficult for rats and other predators as Robins and Yellow-crowned Parakeets are found up the Clinton Valley in fair numbers, but not in the western valleys. The Robin is grey and white, though has a similar stance and mannerisms to the European Robin with its red breast that is seen on Christmas cards. It has a beautiful loud song that sometimes lasts for 30 minutes non-stop in late winter and spring. The parakeet is bright green, shining in the sun, though difficult to see among the leaves in the forest canopy, its favourite part of the forest.
Where the forest starts to thin to more alpine species, and in the alpine areas of scrub, grass and rock Kea are often seen playing in the turbulent air currents around cliffs, their red underwings contrasting with the bottle green of the rest of their plumage. The only hut we saw them at was Mintaro, where someone unfortunately left a white sock out on the veranda and the mischievous bird thought it was in heaven. Other birds only encountered in the alpine zone were the Pipit, a brown bird with a long constantly-wagged tail, and Rock Wren, a close cousin of the Rifleman with a similarly high-pitched call of three notes that lives in the alpine plant gardens and jumbles of rock.
At night kiwi were heard calling at both Clinton and Mintaro Huts. These were the Southern Brown Kiwi. The male has a shrill call, the female a gravelly rasping call. Long-tailed Cuckoos also called as they flew around at night in search of mates. They have a strange screaming ‘wheeesht’ call that is not at all what you would expect from a bird. In the daytime they search out the nest of Brown Creepers. In this area they would also have searched out Yellowheads, but they became locally extinct many years ago. Long-tailed Cuckoos are migratory, arriving in the South Island in early November and departing in February. Their range when not in New Zealand is on islands in the tropical Pacific from Palau in Micronesia to Henderson Island in the Pitcairn archipelago.
The main place waterbirds were seen was on Lake Ada, a few kilometres from the end of the track at Milford Sound. Here there were Black Swans, Mallard hybrids, New Zealand Scaup (a blackish diving duck) and one Brown Teal. Brown Teal were introduced to this area from the North Island maybe 10 years ago in an attempt to reintroduce the species to the South Island. The species had died out a few years before in the South Island, and its last refuge was Fiordland. Brown teals are a small chocolate brown duck, the females entirely so, the male sporting a greenish head. The rarest species of duck in mainland New Zealand they mostly feed at night and like dense marshland or forest cover in the daytime in which to hide. The one bird I saw was resting on a bank of the lake, which is a habit they exhibit in the North Island.