Kiwi Population Growth

Annual Kiwi Count – Adult population estimate of 1,265 kiwi

As a measure of the effectiveness of our kiwi recovery work we put a big effort into the tricky job of counting the kiwi population at the Whangarei Heads.

Each year at 19 listening stations we count the number of kiwi calls, and more importantly work out an estimate of the actual kiwi numbers from directional data locating each kiwi at the listening sites. This year we had human counters working hard at 14 of these sites and Kiwi Listening Devices (KLDs) at the other 5 sites. A good human counter is far superior to a KLD as they can assess the direction of the calls but KLDs have the advantage of being on site every night for a longer period as they don’t have to deal with busy human life issues or inclement weather!

We now have all the data from the human sites but the KLD data is still being analysed – it is a very busy time of year for this and there is understandably a back log for the Kiwi Coast analysists to work through.

This year the timing of the count coincided with difficult listening conditions for us – windy, wet and heaps of surf noise- so we were expecting a drop in the calls heard compared to actual calls that would be heard under calmer conditions.

Without the KLDs data our average kiwi call count is currently 12.3 calls per hour per site – this is the same as last year’s and well up on the 2002 average of 2.9 calls.

Using the human directional data and our population model the estimated adult kiwi population comes out as 1,265 kiwi.  This compares with last year’s estimate of 1,330 and only 80 back in 2001.  Considering the counting conditions this is a very good result with the likely actual number of kiwi higher. The take home message is that our community can be proud of its effective kiwi recovery work through good stoat control work and good dog control by the vast majority of dog owners in the area.

When the KLD data is completed I will do a full kiwi count report with modelling numbers, long term trends for each site etc.

But we had two known kiwi deaths in the past month

We can celebrate our successes but there are also losses:

 A dog killed kiwi was found by a local on the waterfront at Little Munro Bay on July 24.  He was a healthy adult male of 1950g but had obvious large teeth puncture wounds in his vulnerable chest (see pic).  DNA swabs were taken by DoC for possible dog identification. There have been no known local dogs wandering in that area but visiting fishermen sometimes bring dogs with them when they are launching boats there or walking around to the point to fish – the dog owner may not have even seeing their dog kill the kiwi, particularly if it was dark.  So the message is the same for those of us with dogs – keep them under control at home and walk them on a lead- especially at night! Please politely remind any visitors with dogs to do the same – they may be unaware of the huge community effort to grow our kiwi population. If in doubt please give me a call.

We also had a kiwi killed on the road this month-14/7/26.  Looked like a young female.1750g and 96.8mm (see pic). She was hit just the town side of the Nook Road turn off. Maybe she was on the road looking for new territory with fewer kiwi?

Neither of these dead kiwi had ID chips so were locally hatched and grown, which is a good indicator of the effectiveness of the local stoat control.

Backyard Kiwi Predator Control Program :

July catches: 1 stoat, 2 weasels, 1 cat, 60 rats, 4 hedgehogs and 5 possums

Catches have dropped right off as is expected for this time of year.

If you or your group do rat control at your place this is a good time to do a toxin pulse with rat numbers low and vulnerable and bird nesting coming up.

Controlled Kiwi saver toxin pulses, in bait station networks, have been carried out in strategic areas and will have done a fantastic job of not only rat and possum control but of cleaning out any trap shy stoats. With kiwi chicks (and plenty of other birds) hatching in the next month or so this is great timing.

Kiwi nesting well underway

Spare a thought for the many kiwi dads out there patiently incubating the large eggs laid by their hard working mates. The dads are in for 90 days plus with only a few hours off the nest each night for a quick feed and toilet stop. The recent very cold weather would have made their diligent nesting even more important for egg survival and development.  See below for the details of the radio monitored kiwi dads that are currently nesting.

Bird Flu

We are keeping up to date with MPI and DoC advice over H5 Bird Flu.  At this stage kiwi are considered to be at low risk – partly as captive kiwi overseas have been ok to date but mainly because of kiwis’ territorial behavior keeping them well spaced over the land, minimizing the spread between kiwi (other mobile bird species may still cause problems for kiwi).  Even so we are being extra careful when handling kiwi to sterilise hands and equipment between kiwi to minimise any spread risk. Any transfer of kiwi will be carefully considered but at this stage will go ahead as normal. The predicted drought may also complicate things for any transfers.

What your kiwi are up to:

Recently released kiwi: – all doing well

• Owhi– After returning from Telfer road in June she has remained in a relatively small area in the upper Rukawai Valley. A landowner there has reported hearing a male kiwi – maybe Owhi is getting to know him. 12.5 hours average nightly activity.
• Tumanako– After his/her travels south last month he bounced back to the Martins’ block before heading NW up the Rukawai valley, into the deeply incised area near the end of Owhiwa Road. I met a few new land owners on my travels tracking him/her. 13 hours nightly activity.
• Flaxy – After heading to the south-eastern corner of the Owhiwa Road pine block last month she has been wandering around and has spent time to the south in Kohinui valley before bouncing back and heading north to the northern end of the Martins’ block.   12.5 hours average nightly activity.
• Kua tae– After his release in May (via Whangarei Heads School) he still hasn’t moved far from his release site at Owhiwa road. 12 hours nightly activity.

 Whangarei Heads/Parua Bay  Radio monitored kiwi:–

Nesting well underway

• Teina– In his usual valley of pampas and pines at the northwestern end of Martins’ pine block. No sign of nesting. 11 hours of activity.

• Beach Girl – In the pampas on Halses’ cutover pine block at Ross road.  10 hours of nightly activity.

• Murdoch  – He had been nesting for 21 days on 20/7/26. He is in a pile of pine stumps in the logged area of the Halses’ block at Ross Road.  3.5 hours nightly activity.

• Humphries –  North-eastern end of Martins’ pine block.  Located his nest in a dead pampas bush beside the creek there (see pic). 38 days nesting on 27/7/6/26. Good low 2.5 hours nightly activity.

• Wally –Nesting 36 days on 28/7/26 in his usual area of pampas/pines/gum trees at Campbell road (see pic). 1.5 hours nightly activity, Wally traditionally has had very low activity during nesting so he is true to form. I have spoken to the landowner and the grazier and they are avoiding the nesting area.

Kiwi that have walked to other areas:

• Whareora Landcare area/NRC pines:  Te Motu Manu Hine–    She is still in the NRC pine block behind the Money factory but slightly north of her usual area.  12 hours of nightly activity.
• Tamaterau/Waikaraka: Kim– After her return from her big trip to Waikaraka in May she has remained close to her March 2025 release site at Owhiwa road.   A busy 12 hours nightly activity.
• Whanui Pine Block:Ping –   Carl from Pataua North Landcare is monitoring her – she is still in a similar spot in the Whanui Block.

Purua ONC dads

Nesting is well underway here too:

• Buddha – In the paddock north of McGraths’ quarry, his nesty looking burrow is now confirmed by radio activity data stream – 15 days in on 21/7/26 and down to 4 hours activity.
• Macio – South Purua reserve.  11 hours of activity.
• 64 –  Usual area SW Purua Reserve. Nesting 22 days on 21/7/26 with 3 hours of nightly activity.

• Tahi– At the back of Alisons’ farm. Nesting 11 days on 21/7/26 but his activity is still high at 10 hours so things are not looking great for a successful nest.

• Sam –  Back in the SW area of the Purua reserve. 10 hours of activity.

• Derek – Nesting in his usual area on the south face of ‘stump ridge’- SE Purua reserve.  14 days in on 15/7/26 but he may have been nesting longer as it is the same nesty looking burrow that he was in back on 16/6/26.   Nightly activity of 6 hours. The nest is on the Doc trapping track there so I have put a warning sign up so that it is avoided.

• Fletcher –  He did manage to start a nest this season but it failed at about day 21 – there was a single rotten and infertile egg in it. Fletcher was in a fallen epiphyte 100m down from there in a steep gut above the Lovells’ airstrip. I caught him and removed his transmitter as he hasn’t successfully bred in 3 years. He was 2100g and PM condition (see pic) – he has been in a difficult area to monitor so I’m pleased to have him off the books.

• Rua – At the back of Alisons’ farm. Nesting 22 days on 23/7/26. Activity of 3 hours so looking good.

• Erima – He has been in the stand of native in the paddock on Hawkins’ hill since being transmitted in May last year and had a transmitter change in May this year in one of his usual burrows. I got a signal from him last month but after having a decent search for him this month I can’t get a signal – I will have another look next visit.

• Prime – Near the top of Hawkins’ hill. Nesting in the scrub there. 28 days in on 15/7/26 with 4 hours of nightly activity (see pic).

• Purua– High up on the northern face of the crater area of Purua Reserve.  His transmitter change is overdue but he has  been in nesty looking areas with the odd low night of activity so I have left him. When his activity was well up (13 hours) I couldn’t reach him in a very deep stoney burrow.  When I returned on 23/7/26 I couldn’t get a signal for him anywhere in his usual areas – will look wider next visit.

Cheers Todd

Todd Hamilton

Backyard Kiwi Project Manager

Whangarei Heads Landcare Forum