Some endangered birds from Great Barrier Island New Zealand

[KiwiGran]

Just back from a week on Great Barrier Island and thought members might be interested in some of the endangered birds found there.

 

Firstly the NZ Dotterel (Charadrius obscurus) Maori name Tuturiwhatu pukunui

 

To quote from the Department of Conservation (DOC) pamphlet. “The NZ Dotterel is an endangered shorebird found only in this country. It was once widespread and common, but there are now only about 1700 birds left. This serious decline in numbers is due to a combination of habitat loss, predation by introduced mammals and disturbance during breeding.

NZ Dotterels are usually found on sandy beaches and sandspits or feeding on tidal estuaries. They are largely pale grey-brown on the back, with off white underparts which become flushed with rusty-orange in the breeding season. They can be hard to see because their colouring merges effectively with the background of sand, shells and dune vegetation in their environment.

 

We were lucky enough to see them on two occasions. The first afternoon after we arrived we went for a walk at Okupu Bay. I spotted a Dotterel on the sand about the high water mark.

 

 

 

Fascinating to watch as they dart about looking for food – marine and land invertebrates, occasionally small fish. Sand hoppers are a common prey on beaches.

Our second sighting was a few days later on the same beach and this time I saw the pair on the same stretch of sand and another bird in amongst a group of seagulls and terns. As I approached to take a photo, the terns and seagulls all flew off but the dotterel remained and just ran a few metres away. I stopped at that point as I didnt want to disturb it but I think it takes quite a lot to make them fly. One of the pair sat down and even though I knew where it was it was incredibly hard to see.

 

 

 

 

Their nest is just a scape in the sand so they are very vulnerable to predation. There are a lot of conservation efforts being made to protect them on Great Barrier so hopefully their numbers will increase.

 

Brown Teal (Anas chlorotis)  Pateke

 

Pateke are a rare dabbling duck found only in New Zealand. Originally common throughout New Zealand they are now confined to 3 small areas, Great Barrier having the largest population of 700 to 900.  They generally feed at night, dabbling for aquatic and terrestrial invertebrates in wetlands, estuarine areas and short grass paddocks with surface water. In summer they may feed on estuarine areas during the day.

 

We had several great sightings of these lovely little ducks. The first was again at Okupu Bay on our first afternoon. We had walked along the beach and found a track over a headland to another bay and as we descended to the beach I spotted 3 birds at the waters edge. As we got closer I was excited to realise these could be Pateke. When we reached the beach we quietly approached and sure enough they were Pateke dabbling in the shallow water and rock pools. I had never seen ducks like this before and was fascinated. We have the NZ Scaup or Black Teal in our area but they are a diving duck – we delight in watching the ducklings who dive from a very young age.

 

 

 

Our second sighting was at Glenfern sanctuary in the Northern part of the island. This Sanctuary was started by Tony Bouzaid in 1994. He predator fenced the peninsula off from the main area of the island and began the huge job of planting thousands of trees and trapping predators. Great Barrier is free of mustelid predators like the stoat which decimates birds on the mainland, free of possums which both heavily browse on the vegetation and will also take birds eggs. The main predators that are currently being trapped are feral cats, ship rats and kiore (pacific rats).

 Tony died in 2011 and in 2016 DOC took over the management of the Sanctuary. We did an hour and a half loop walk which sadly yielded very few birds but we did find a pair of Pateke on a small dam and I was able to get some good photos which pleasingly show the green tinge on the head of the male.

Pateke pair

 

Male Pateke

 

Female

 

Our third sighting was again at Okupu, we had walked both beaches and on the way back I walked a little way up beside a fresh water lagoon and there I spotted the pair sitting on a fallen log.

 

 

The third bird I would like to feature is one that we didn’t see as they only occur on Mount Hobson (although Glenfern does have a burrow) and the walk to the summit was too challenging for me. Also they are nocturnal so difficult to see. But wonderful to know they are thriving on Great Barrier.

 

Some information from this website http://blog.forestandbird.org.nz/monitoring-black-petrels-on-great-barrier-island/

Barrier Island’s Mount Hobson (Hirakimata) stands 621 metres tall and is home to the largest breeding colony of black petrel (taiko) in the world.

The slopes of Mt Hobson are covered in semi-mature forest, with the remnants of precious ancient conifer forests. The forest is filled with endemic plants found nowhere else in the world, such as totara, rimu, kirk’s pine, and kauri. During the day the mountain is dominated audibly by prehistoric raucous call of kaka, coupled with contrasting melodic tones of the grey warbler.

As dusk turns to night, the summit of Mt Hobson comes alive with the distinctive clamour of black petrel clacking. This is the male being as vocal as he can to ensure he attracts a mate for the season.

Black petrels can also be heard crashing through the forest as they descend for their nesting burrows. They can be seen gliding above, silhouetted as they ascend into the night after launching from the summit or Launch Rock.

Great Barrier Island holds the largest colony of black petrels in New Zealand. On the island, the estimated 2700 breeding pairs have fewer land based threats and are able to breed in relative safety. Classed as “Nationally Vulnerable”, they have been wiped out across much of their original habitat by introduced predators. They are often caught accidentally by recreational fishers and are the most at-risk seabird in New Zealand from commercial fishing.

Black petrels are remarkable birds with unique lifecycles. They are found in New Zealand’s waters between October and June but spend four months in South American waters. There, they take advantage of the Humboldt Current that sustains a wealth of marine life important for essential foraging.

 

North Island Kaka and Banded Rail are 2 other birds that are thriving on Great Barrier but in limited numbers on the mainland. I will feature these in a trip report which I will post later.

Edited March 31, 2021 by KiwiGran

[offshorebirder]

Thanks @KiwiGran - Charadrius obscurus looks VERY similar to Charadrius wilsonia, its beach-nesting relative in North America and Central America.

[KiwiGran]

Thanks @offshorebirderIt is fascinating how species develop in similar ways in different parts of the world.

[KiwiGran]

While I dont have photos of the North Island Kaka (Nestor meridionalis) at Great Barrier where we only saw them flying over I do have this photo that I took at Maungatautari Sanctuary. This one is ringed but they are wild birds in a predator fenced sanctuary of 3400 hectares with 47 km of predator proof fencing, a very large conservation project.