Fiordland Kiwi Diaries: The everyday lives of kiwi

An extract from a field diary of a ranger written in December 2023 during a monitoring trip to check on tokoeka kiwi chicks. (Includes nest cam footage!)

By Angus Prichard, seasonal volunteer ranger

“I’ve got eyes on the chick” Monty whispered excitedly, indicating to me where I should stand. I quickly positioned myself to cover potential escape routes from the mossy tangle under which a young kiwi was hiding.  

With a confidence that belied much experience, Monty reached into the dark hole. A smile of relief spread across his face.

“I’ve got a leg!” 

He gently pulled out a wiggling and sniffing little kiwi. He cradled it and it instinctively stopped struggling. “He’s a fiery little guy, eh?” he quipped, carefully handing me the bundle of fluff. 

We’re well into the second half of the kiwi monitoring season here are Shy Lake. Most birds have completed their first nesting attempt, and the rangers are waiting for more pairs to start incubating their second egg of the season. This is typical of Southern Fiordland tokoeka kiwi, which nest twice each summer.  

Monty Williams and Chris Dodd (Doddy) are the two rangers currently tasked with keeping tabs on this population study of tokoeka, which are all fitted with small radio transmitters. Other than the radio signal, the only sign of kiwi activity is an occasional footprint in mud or snow, or a distant call heard at night.

I have been very lucky to help out this season as a volunteer with the Shy Lake team, as part of a grant program from the USA. Since I’m not a trained kiwi-catcher, I have mostly been useful as an extra set of hands to hold birds while Monty or Doddy change their transmitters. Having dreamed of simply hearing or seeing one since I was a kid, holding a kiwi is an experience I’ll not soon forget. 

There are currently 12 adult kiwi and two sub-adults (kiwi teenagers) wearing transmitters at Shy Lake. To differentiate between kiwi the rangers use a set of easy-to-remember names. This makes for brilliant written plans for monitoring trips. A typical plan might read: 

Day one: 

• Change camera at Sinbad’s and Pegleg’s nest burrows. 
• Check Cake’s transmitter status. 
• Get a transmitter readout for Bones, Flame and Hook.  
• Do a night stakeout for Long John Silver’s chick.  
• Camp at lake shore. 

During the first round of nesting eight kiwi pairs laid eggs. As of mid-January, the first of these chicks has made it to the respectable size of 1kg. Most importantly there has been no evidence of stoat activity, which is a good sign that the 1080 treatment is helping.  

In previous years nearly every chick that hatched was killed by stoats shortly after leaving the nest. They are vulnerable to stoat attacks until they reach around 1kg, at which point the stoats tend to leave them alone. 

The more frustrating news from this season is that the other six nests failed for other reasons. A late spring snowfall was too much for one small chick, unable to withstand the cold and lack of available food. Another chick was taken from its burrow by a kea, a rarely recorded and difficult-to-witness interaction between two native species. One unlucky chick simply fell down a hole near a stream and drowned, and for reasons unknown, three eggs never hatched.  

As Doddy explained to me, it’s likely that this is a normal year for this species. They’ve been living in the harsh, changeable weather and steep terrain of Fiordland for a long time, and this season’s conditions are nothing new to them.  

Since kiwi can live to be quite old (possibly even more than fifty years!), each pair only needs to successfully raise a few chicks over their lifetime for the population to remain stable. This means that in any one year, only a couple of chicks might survive.

The trouble with their “slow-and-steady” biological strategy is when stoats start eating chicks, and the chicks that would have otherwise survived to adulthood don’t make it, that’s enough to cause the population to decline. 

But what does a Southern Fiordland Tokoeka’s day-to-day life look like?

The team has a set of  motion-sensor cameras installed on active burrows which monitor the comings and goings of Pegleg, Cake, Sinbad, and their neighbours during the breeding season. Unlike colony-nesting birds, which often show similar nesting behaviour across the entire population, the solitary lives of these kiwi differ quite a bit from bird to bird. 

The most basic parts of their year-to-year habits are the same. The male birds defend their territories, and each one excavates several burrows in his home range. These are usually below overhung banks or between the roots of a large tree, where a natural hollow provides a nice cosy starting spot.  

Lucky males are visited by a female, who chooses the burrow she prefers and lays a single, massive egg. It’s then the male’s job to keep it warm until it hatches. Each evening, the female typically sits on the egg for a spell to give the male a break to feed. They sometimes even ‘sing’ a duet when both birds are at the nest. 

After about 70 days of incubation, the chick will hatch. After hatching it still has a special yolk sac attached to its belly which acts as a food reserve for about five days, which is essential since the adults don’t feed the chick. It must start feeding itself before the reserve runs out. This means exploring the wide world outside the burrow.

Beginning with short visits to the entrance, the chick will build up the confidence to step outside, probing the moss and dirt for insects. Sometimes they even leave the nest during the day. 

After the first few days, the chick starts to roam further and further each time it leaves. Though often it will still be quite attached to the safety of the burrow. 

Commando is a remarkable kiwi who stays in his burrow year-around, sleeping there every day and only coming out to feed. The transmitters fitted to the birds’ legs record their activity level, and send a special signal when they start sitting in one place for a large part of their daily cycle. This typically means that they’re incubating.

However, Commando’s transmitter is always sending the incubation signal because he’s as inactive as an incubating bird! Here he is emerging from his burrow and tidying away a few leaves.  

His burrow is regularly visited by weka, and it’s unclear whether they might be hoping to steal an egg, or are just curious about the hole in the ground. What is clear is that Commando isn’t fond of their company whatsoever.  

Other frequent visitors to the burrows include riflemen (titipounamu) which can often be seen collecting stray kiwi feathers to line their nests. South Island robins are also frequently captured stopping by to grab some invisibly small morsel of food, and then flitting off into the understory. 

I’ve since headed back to the states, but I am extremely grateful for the chance to walk up and down some of Fiordland’s steep, mossy slopes, alongside kiwi and some remarkable DOC rangers.  

Seeing how this and other projects are conducted has given me a profound respect for the scope and quality of the work DOC is doing across the Fiordland landscape.  

Recent analysis has shown that the current management techniques at Shy Lake are paying off, which means that with continued support, these kiwi might have a brighter, stoat-free future. 

---

Postscript: We just got some amazing news from Fiordland about this population. We have evidence that the aerial control has worked, and for the first time ever, the population is growing. Read more about it here: Remote kiwi population growing for the first time in history.

To learn more about this project, and watch Doddy, Monty and Tim Raemaekers fight to save this population from an onslaught of stoats, watch the Fiordland Kiwi Diaries miniseries on YouTube.