News

The news we didn’t want to hear but have expected for some years arrived today, 15 July 2026

The news we didn’t want to hear came through late this afternoon, 15 July 2026. “Seabird found on Wellington beach tests positive for H5 bird flu” Here is the RNZ news item including the press briefing video: https://www.rnz.co.nz/news/environment/723404/seabird-found-on-wellington-beach-tests-positive-for-h5-bird-flu The West Coast Penguin Trust is prepared, DOC is ready, MPI is ready – but every person in New Zealand needs to understand what this means and what they can do to help. The Ministry for Primary Industries, MPI, with its biosecurity role, is leading this work. Their resources are on their website here: https://www.mpi.govt.nz/biosecurity-in-nz/dont-let-bird-flu-take-flight The resources include this introductory video. And this one pager – Bird Flu Be Ready: https://www.mpi.govt.nz/dmsdocument/64557-How-to-report-suspected-bird-flu   Key rules from MPI, are below.

What to do if you find sick or dead birds

When out and about, especially on beaches, keep an eye out for wild birds showing signs of bird flu.

The most obvious sign of HPAI is sudden death in several wild birds. Other signs can include weakness, tremors, paralysis, difficulty breathing, lack of co-ordination, blindness, trembling, and diarrhoea.

If you see 3 or more sick or dead wild birds in a group, report it immediately to the exotic pest and disease hotline on 0800 80 99 66 so we can investigate the cause.

Added by DOC - OR report it if you see a single sick or dead high-risk seabird.  These include skua, giant or cape petrels, and albatross, which are rarely seen on the Coast, and white-fronted tern, which nest on rock stacks and in river estuaries.

Do not touch or collect sick wildlife - birds or seals.

Keep pets away from wildlife as the disease can spread to other animals.

Avoid disturbing wildife congregating on shorelines.

Clean your shoes and gear before and after visiting beaches, parks, reserves, or farms, to stop the disease from spreading.

When reporting sick or dead birds, provide as much detail as you can, including:

• • a GPS reading or other precise location information
  • photographs and videos of sick and dead birds
  • species name and estimate of the numbers affected
  • how many are sick or freshly dead, and the total number of birds present.

MPI will note the details and one of our specialist biosecurity investigators will assess the information and contact you.

Sick birds can recover from this disease, so leave sick birds alone, and reduce stress or disturbance around them.

  It's important to note that recent reports including this skua have been isolated incidents, just single birds.  So it's important to be aware of unusual bird behaviour. Do not hesitate to ring the MPI hotline if you have any concerns. Thank you for doing your bit.   Information we provided a couple of years ago: https://www.westcoastpenguintrust.org.nz/news/being-prepared-for-avian-influenza-or-bird-flu/

Tawaki have a good year, kororā struggle

Results from the 2025 penguin breeding season are in. Here on the West Coast, as they do around the world, penguins face ever-changing challenges.  Despite notable losses at key breeding sites, our Little Penguins (kororā) and Fiordland Crested Penguins (tawaki) continue to respond with remarkable resilience.  Your support helps us to understand and respond to the rapidly changing conditions that our penguins face every day and we are enormously grateful.   Here’s some of what we achieved and learned from the 2025 season.

• 31 kororā microchipped this season (now 77 in total)
• Kororā travelled up to three times further offshore than usual, staying away much longer than expected to find food during egg incubation
• Lower breeding success at key sites reflects likely environmental stress
• Joyce Bay colony strongly rebounded in breeding activity
• Tawaki had a stable season despite some unexplained chick deaths
• No stoats seen at the tawaki colony monitored with cameras, demonstrating the success of DOC’s predator control efforts in 2025 (as per our advocacy) and benefitting penguins breeding there.

 

Little Penguin (kororā): 2025 season updates

31 new penguins microchipped

  31 kororā were microchipped this season, bringing the total to 77 across two seasons. We aim to microchip all penguins in the study colony that can be reached, both adults and new chicks each year, once they are big enough, giving us information about individual birds - their arrival, their survival and their return.   Next year, after three years of data collection, this dataset of the demography of these penguins, along with breeding success data, will reach a point where it will start revealing survival rates and colony growth or decline.  We will then be able to link that to foraging patterns and changing marine and weather conditions. Critical insights like these are key to guiding and informing future conservation decisions and efforts.   

Foraging study reveals surprising findings

Using tiny GPS and dive loggers, we were shocked to find that kororā from our study site travelled up to three times further offshore to find food during the egg incubation stage.  It seems they were out at sea much longer than in previous years too.  With daily checks on the nests, one took nearly 3 weeks instead of the expected 5-7 days to return. For these breeding birds, that indicated a much tougher time finding food, and a tougher time for the increasingly hungry parent left to keep the eggs warm. 

 

Extreme journeys early in the breeding season are a likely indication of reduced prey availability within the usual foraging range. This may have been due to higher sea surface temperatures associated with weak La Niña conditions. Thermal stratification locally (warm surface water) may lock nutrients and small schooling fish at depth and sediment in the top warmer layer, reducing visibility, essential for penguins to find prey fish.  We will be investigating this in the coming months with the help of our scientists and will report back. Find out more about our foraging study and last year's results here  

Breeding success down from the previous year

  Overall, we recorded more nest failures, underweight chicks, and early chick losses than in most previous seasons. At our main study site at Camerons near Greymouth (replacing the 'Knoll' site near Charleston), several nests failed, and many produced only one chick from the two eggs laid. With no evidence of predation, and taking into account tracking data from our foraging study, the signs point to environmental stress, probably reduced prey availability early in the breeding season. Find out about the 2025 kororā breeding season here The very poor season in 2022 also appears to be related to environmental stress, most likely La Niña conditions that peaked in early spring, part of a rare three-year 'triple-dip' phenomenon extending to March 2023. Those conditions led to elevated risks from weather extremes and we saw unprecedented marine heatwaves accompanied by dropping indicators of primary production such as chlorophyll levels, an indicator for phytoplankton, the base of marine food webs. There was a weak La Niña in 2025.  We assume these conditions push prey fish out of the usual foraging range of kororā and we will be doing more work to understand that. Read our article about La Niña and El Niño here  

Resilience and recovery 

Despite tough conditions, kororā on the West Coast continue to show remarkable resilience. Many penguin parents successfully raised chicks despite significant early foraging challenges. Some colonies, notably at Joyce Bay, experienced a strong rebound in breeding activity compared to previous years. This is incredibly promising evidence of the adaptability of Little Penguins, and indicates that even when hope is fading, colony recovery is possible.  

Fiordland Crested Penguins (tawaki): 2025 season updates

A steady breeding season

  Encouragingly, camera-monitored tawaki nests at our key study site showed high breeding success rates (~90%), though lower success was found using broader monitoring measures (~65%). Varied results likely reflect monitoring limitations, and the camera-monitored figure will be more accurate.  Monitored chicks appeared well-fed and showed normal growth rates, suggesting that food availability, unlike for kororā, was not a major issue for tawaki this season. 

Read our tawaki season news here  

Mysterious chick deaths

A small number of healthy tawaki chicks were found dead without signs of predation. Possible causes include parental loss or unknown environmental factors. We aim to continue and improve our camera monitoring so that we can learn more about such scenarios.   

Predator management success for tawaki

We have used cameras to monitor the risk of predation of tawaki eggs and chicks since 2014. This season, no stoats were seen at the tawaki colony monitored with cameras, which demonstrates the success of DOC’s landscape-scale predator control efforts there earlier in 2025.  From our previous monitoring, we have concluded that stoats are a major threat to tawaki when these mustelids are in plague proportions, so predator management will certainly benefit penguins breeding there.

 

What’s happening in 2026?

Over nearly 20 years, we have seen the challenges our penguins face grow, but we have continued to develop our ability to understand those challenges and respond. Where we have already responded, with penguin protection fences, campaigns to protect penguins from loose dogs, and our much-valued education programme, we have seen reductions in the numbers of penguins killed on the road and by dogs as a result. With your support, our ongoing penguin monitoring and research efforts will drive improved knowledge of kororā and tawaki, ensuring we continue to make a lasting impact on their future here on the West Coast and continue to work towards our Vision:

"Sea and shore birds, and their habitat across the West Coast Te Tai Poutini, are healthy and thriving."

  Here’s our focus for 2026:

• Continue microchipping new kororā chicks as well as adults that may be new to the study colony or that we haven’t been able to reach before. This will build a long-term dataset that tracks survival and population trends, and, with our foraging study, help us better understand how changing environmental conditions may be affecting West Coast penguins 
• Continue our kororā foraging study during egg incubation and chick guard stages
• Upgrade kororā nest boxes at our study site
• Maintain penguin protection fencing that is serving so well to save kororā lives
• Improve tawaki monitoring with better cameras and batteries, and improve our understanding of the variable timing of egg-laying and thus chick rearing to improve our data collection and analysis
• We will be monitoring forecast El Niño conditions and hope that they will not impact penguin breeding success.  The last major El Niño event led to almost total breeding failure for tawaki in 2015
• Maintain our education programme, supporting teachers and youth leaders to deliver educational resources through lessons, activities and beach visits
• Work with DOC and District Councils to update beach access signage that will encourage responsible dog ownership: keeping dogs safe reduces the risk of dog attacks on penguins and other wildlife
• Maintain our advocacy programmes to protect penguins, other endangered seabirds, and their nesting and foraging places here on the West Coast
• And we might find a way to celebrate 20 years since the West Coast Penguin Trust was born!

 

90-100% breeding success for tawaki monitored by WCPT - a good year!

On the wild and rugged coast of South Westland, remote colonies of Fiordland Crested Penguins or tawaki breed each year between July and December. We have been monitoring up to three of those colonies since 2014. The early focus of this study was to identify and understand any predation trends on tawaki eggs and chicks by introduced mammals. Now, over a decade later, our main focus at our study sites is tawaki breeding success: monitoring nesting behaviour, chick growth and health, and indications of overall colony growth or decline. In addition, at one of the three sites, we monitor predator presence and activity.

 

Monitoring breeding success at Gorge River

The 2025 breeding season was a successful one at our key study site at Gorge River, though results varied between nests that were monitored by camera and those that were not.  With all birds sitting on eggs from August 22, the season ran at average to late timing compared to previous years. Over the course of three months, chicks were seen to be well-fed and growing at an average rate. 

  Our method: 

• 24 nests checked over 3 months, from August to November
• 10 additional camera monitored nests, providing the most accurate results
• 2 cameras were lured & baited to assess predator activity in the area (mainly stoats).

Breeding success for Little Penguins or kororā is measured by the number of chicks fledged from both eggs laid (two = 100%).  However, for tawaki, with a very different breeding strategy, breeding success is measured by the number of chicks assumed to have fledged per two eggs, and 100% = 1 per nest.  In years or locations where food is plentiful, two chicks can occasionally be raised, but that's the exception rather than the rule.  Here’s how the results unfolded. 10 camera-monitored nests, high accuracy results: 

• 10 breeding attempts 
• 2 nests attempted to raise 2 chicks 
• 1 failed nest 
• 9 fledged chicks
• 90% breeding success 

24 nests not camera-monitored, lower accuracy results:

• 24 breeding attempts (assumed)
• 7 failed nests (cause undetermined)
• 17 fledged chicks (estimated)
• 65% breeding success 

For nests not camera-monitored, the true number of failed nests is undetermined, as it is difficult to check for eggs without disturbing the penguins. At the time of nest checks during the incubation stage, tawaki that appeared to be sitting on eggs may not have had eggs in the nest at all.  Therefore, the most accurate indication of breeding success is from camera-monitored nests. And, from the 90% success rate recorded from camera-monitored nests this year, the results look good. This is a significant improvement from 2024, when camera-monitored tawaki nests had a 66% breeding success rate. From 2019-2025, the average breeding success assessed using cameras in this colony is 92%. There is another challenge in terms of counting fledged tawaki chicks. Chicks congregate in crèches, or a communal nursery, from about 3 to 4 weeks old. They leave their nests to huddle and socialise in small groups while both parents head out to sea to forage and meet the needs of their hungry, growing chicks.  

Mystery chick deaths at camera-monitored site

Two of the camera-monitored nests in 2025 attempted to raise two chicks instead of one. One nest showed particular promise: both chicks were growing healthily, and at equal size to each other. It appeared that both were headed to fledging.  However, in early October, Gorge River tawaki ranger, Catherine, found both chicks in this nest dead, and unfortunately the camera had failed. There were no signs of predation, and one parent was present at the nest.  The cause of the chicks’ death is unexplained. Besides predation, the likely cause of chick death in tawaki is the death or abandonment of a parent, leading to loss of food supply and starvation.  Though both chicks were at a healthy weight, it is possible that one parent died at sea or abandoned the nest, leading to starvation in the chicks that happened too quickly to show signs of emaciation. Another possible explanation is that one parent brought home something poisonous.  In another nest raising two chicks, one chick was unfortunately growing slower than the other, and did not make it. Again, with no sign of predation, the likely cause of death was competition for food from the other, stronger chick.

  Predator assessment: lured and baited cameras We have used cameras to monitor the risk of predation since 2014. From earlier monitoring, we found that stoats are a major threat to tawaki eggs and chicks when stoat numbers are at plague proportions. This year, our predator monitoring showed encouraging news. No stoats were seen at the two baited cameras or any nest cameras this season, demonstrating the success of DOC’s landscape-scale predator control efforts earlier in 2025.  

Secondary study sites

  Alongside our key study site in the early years of our research, we monitored for predators and predation at two other South Westland colonies.  Since 2019, we have monitored tawaki breeding success at these colonies.  In 2025, our ranger, Lucy, along with her volunteer assistants, monitored breeding success at these colonies through two nest checks: 

• The first nest check takes place during the incubation stage, when penguins are sitting on eggs and taking it in turns to feed themselves or keep the eggs warm. 
• For the second check, we aim at the chick-guard stage, where, after hatching, one parent stays behind in the nest to warm and protect the vulnerable chick, while the other parent hunts for food. It is desirable to check as late as possible in this approximately three-week stage to ensure the most accurate representation of chick survival.

It was a steady year for breeding across both colonies.  Let’s start with our largest one.  Colony 1 (Jackson Head):

• 30 nests checked
• 22 active nests
• 20 breeding attempts 
• 0 failed nests 
• 20 fledged chicks
• 100% breeding success

This colony has shown real promise over the last two years, repeating its 100% breeding success from 2024 (one chick raised per breeding attempt). Overall, this site has an average breeding success rate of 97% from 2020 to 2025. Colony 2 (Knights Point area):

• 19 nests checked
• 10 active nests 
• 10 breeding attempts 
• 1 failed nest 
• 9 fledged chicks 
• 90% breeding success

In 2025, this colony saw a 10% increase in breeding success compared to 2024, which is again encouraging. The overall breeding success average here is 90% from 2019 to 2025.  

Accuracy of results

It’s important to note, however, that due to the remote location of these colonies and the variable timing of the tawaki breeding season, it is difficult to predict optimal timing for nest checks, which can interfere with the accuracy of our results. The tawaki breeding season started a little later in 2025 than it did in 2024. Lucy checked nests on the same dates as the previous year, but the second visit during the chick-guard stage was not sufficiently far enough into chick growth to give us strong confidence that the chicks would survive. Many chicks were still small, and it is not clear whether they would have survived to fledging, so the number of fledged chicks is assumed. Our results are therefore informed guesses for tawaki breeding success across these two South Westland colonies. 

     

Importance of monitoring multiple sites

No pattern or consistency is shown across our tawaki study colonies, showing that monitoring multiple sites is necessary. One colony cannot represent the rest.   

What's happening in 2026?

In 2026, we aim to establish the timing of egg laying if possible, in order to visit tawaki nests later in the chick-guard stage, when the chicks are larger. This will help us better determine chick survival to the fledging stage and provide greater data accuracy for overall breeding success.  We will continue to monitor breeding success at our three sites, using cameras at Gorge River for both monitoring and predator observations.

Breeding success declined at key study sites, with more failed nests than the previous season, and many parents fledging one chick instead of two. 

Little Penguins (kororā) on the West Coast faced a challenging breeding season in 2025.  Breeding success declined at key study sites, with more failed nests than the previous season, and many parents fledging one chick instead of two.  News like this proves how crucial long-term monitoring is to determine colony health and identify patterns across seasons. The dataset our ranger and volunteers are building, with the help of our scientists, helps us to connect dots and respond to changing threats that penguins and other endangered seabirds are facing year on year.   

Greymouth Study Site: Monitoring Breeding Success

2025 marked the second season of monitoring at our primary study site near Greymouth. We monitored penguin nest boxes twice a month across the colony, to learn about breeding success. The season was off to a good start, with 23 active nests compared to the 22 active nests in 2024. 

  However, our foraging study at this site began to show unusual trends during the egg incubation period. Tracking data showed monitored birds remained at sea far longer than usual, and travelled unusually far distances (up to 120km, compared to the usual 25-30km) to forage during egg incubation. While hunting for food, penguins left the remaining parent at the nest for much longer than the expected 5-7 days. With extreme journeys pointing to limited food availability close to shore, stress on our study colony began to show.  Click here to read our foraging study report. By the end of the season, there were more nest failures at our key study site (five in total) compared to 2024, and more nests that fledged a single chick rather than two. Overall, we recorded 23 fledged kororā chicks in 2025 - far fewer than the 32 chicks that fledged the previous year. This brought the overall breeding success rate down from 76% in 2024 to 52% in 2025. This sits much lower than the average of 69% breeding success across our study colonies in previous years.  

We also noticed:

• Egg-laying times were significantly spread out in the 2025 season, with some eggs laid weeks apart. In 2024, almost all eggs across the colony were laid within 4 days of each other. 
• All failed nests were in the northern part of the colony. 

 

Predation

This season, we recorded no obvious signs of predation from mustelids (stoats, ferrets, weasels), rodents, dogs, cats, or weka. Stoats could be present at our primary study site. While we don’t believe they pose a current significant threat to kororā on the West Coast, they certainly could do so when in large numbers or, as we saw this year, when hungry chicks are waiting outside nest boxes. The continued efforts of volunteers to trap rats and stoats in this area, established by the Guardians of Paroa Taramakau Coastal Area Trust years ago, are hugely appreciated. This season, they caught one stoat in the colony, just 3 metres away from active penguin burrows.   Land-based predators remain a substantial threat to kororā across Aotearoa. Pōhatu Penguins on Banks Peninsula in Akaroa reported a single stoat killing 15 chicks over two months.   Besides evidence of weka investigating nests and scavenging scraps from meal leftovers, no predator interactions were caught on camera at our study colony over the course of a few weeks.   

Second Study Site

Our second study site has an invaluable and long-standing dataset.  Breeding success of kororā has been monitored there and results generously shared by landowner, Matt Charteris and his family, since 2008.

• Between 2008 and 2019, the breeding success rate (2 chicks fledged = 100%) varied between just over 70% to just below 40%. 
• In 2020 and then 2021, breeding success crept up to 89% and then 94%, but crashed to 45% with the La Niña event of 2022.
• 2023 saw a return to better breeding success at 80%, then falling to lower success rates for the 2024 and 2025 seasons. 

  There is a pattern of highs and lows at our two study sites, though not always a consistent increase or decrease year on year. This confirms that, despite regional conditions such as marine heatwaves, there are also local conditions at play. One colony cannot represent the Little Penguin (kororā) population across the West Coast, so the Trust continues to monitor multiple colonies as resources allow. 

 

A bit more detail from the Greymouth study site:

• Six nests failed in 2025 compared to two failed nests in 2024 (entirely failed nests – both eggs/chicks failed)
• All failed nests were in the northern section of the colony
• Egg laying times were much more spread out in the 2025 season, being weeks apart, in comparison to 2024, where most kororā laid their eggs within 4 days
• While there was a drop in breeding success from 2024 to 2025 at both Rahui and Camerons, it was more marked at Camerons
• The pattern of breeding success, i.e. increasing or decreasing from one year to the next, is similar for Rahui and Camerons and previously the Charleston 'Knoll' study site, but not mirrored, confirming advice from our scientist, Dr Thomas Mattern, that data cannot be extrapolated from one colony to other sites across the region
• Two nests were found each with two dead chicks at the start of the hatching period, which, alongside the long distance and duration of foraging trips indicated a worrying season ahead.

 

Other kororā colonies

There are a few colonies, mainly in the Buller District, which we monitor when we can.  Some we are monitoring twice during the breeding season, to give us in indication of presence and breeding activity.  While results are less accurate than the detailed monitoring at the two study sites, they provide useful information.  Where we saw both study sites see a drop in breeding success, our findings indicated that breeding success increased at our former study site, the 'Knoll', and at Joyce Bay, both close to Charleston.  Ranger Lucy reported joy at Joyce Bay, finding 15 active nests compared to only seven in 2024. Some sites have not been visited for a while and we will be reviewing our approach to this monitoring programme to maximise efficiency while obtaining valuable data where we can.  

Our plan for 2026

Breeding success monitoring is a fundamental component of our work.  Together with demographics obtained through microchipping and following individual penguins each year, as well as the foraging study, we are gradually learning a lot more about kororā.  There is always work to be done and along with sourcing grants occasionally, we rely on our supporters, especially through donations, to keep on keeping on.  Thank you. In addition to checking penguin nests regularly throughout the season, we will:

• Replace any nest boxes or lids that are in disrepair, without disrupting the colony
• Ensure access to the main study colony is minimised and hidden to avoid drawing public attention, after we saw that nest boxes had been disturbed last year
• Update and optimise our online database, improving our penguin archive system for data security and long-term monitoring
• Continue to upskill our valued volunteers
• Continue to microchip new adult penguins and chicks
• Work with our scientists to analyse our data and link it to marine, weather and climate conditions
• Confirm and implement a monitoring programme for non-study colony sites
• Share our findings through our education, awareness and advocay programmes.

The 2025 penguin season revealed apparent foraging stress on Little Penguins (kororā) nesting here on the West Coast.

The 2025 penguin season revealed apparent foraging stress on Little Penguins (kororā) nesting here on the West Coast. From August to September 2025, five tracking datasets were collected from kororā during the egg incubation stage at the West Coast Penguin Trust’s study colony near Greymouth. Tiny GPS and dive loggers recorded where the penguins travelled, how long they stayed at sea, and their dives, giving us their diving efficiency as they foraged beneath the surface. The results indicated a reduction in prey availability, and highlighted both the resilience and vulnerability of kororā in the face of environmental pressures. 

 

Longer trips, extraordinary distances

During this season’s egg incubation period, we were shocked to find that tracked kororā remained at sea for as long as three weeks, instead of the expected 5-7 days, and travelled extraordinary distances offshore. One bird reached a maximum home range of more than 120km, far exceeding anything previously recorded in our work. In a typical season, usual home ranges are around 25-30km, as recorded from earlier studies at at the Greymouth study site and at Charleston.

Extreme journeys such as these are a strong indication of food scarcity close to shore and perhaps beyond. Below-average diving efficiency further suggested that kororā are having to expend more energy than usual to travel to possible feeding areas rather than dive for food. Our findings raised two key questions: what is affecting prey availability on the West Coast, and what does it mean for kororā breeding success?  

Changing ocean conditions affecting prey availability 

Marine heatwaves and shifting La Niña conditions affected New Zealand waters throughout 2025, with sea surface temperatures remaining above average along parts of the West Coast during the critical incubation period for kororā eggs. 

  Warmer waters can alter where prey species gather, potentially pushing food further offshore or to greater depths. This can put food beyond the easy reach of kororā, the world’s smallest penguin, who are naturally limited in both diving depth and range compared to larger seabirds.  We suspect that changing ocean conditions may have played a major role in shaping this season’s outcomes. Click here to read our article about ENSO, the El Niño Southern Oscillation, and how extreme events of El Niño or La Niña are likely to impact penguin breeding success.  

What did this mean for the rest of the 2025 breeding season?

Longer foraging trips during the egg incubation stage place extra pressure on both parents: the one hunting at sea, and the one left behind to keep the eggs warm. When prey is harder to find, consequences can ripple through the entire breeding season. 

At the study site, breeding success dropped significantly to 52% in 2025, compared to 76% breeding success in the previous year.  In other words, a disappointing average of only one chick per nest was raised successfully at the study colony in the 2025 season.  Our data has shown a likely connection between poor foraging conditions during the incubation period and a decline in breeding success later in the season. More nests failed, more chicks died early or were underweight, and as we’ve shown, kororā breeding attempts resulted in an average of only a single chick being fledged instead of two. Kororā faced a difficult year across the board. Click here for a deeper dive into kororā breeding success in 2025.  

Striking evidence of individual resilience

Despite significant environmental pressure, many kororā returned from exhausting journeys to successfully hatch eggs and raise chicks.  We saw them maintain breeding attempts despite difficult feeding conditions that may have stretched across the entire season. 

While feeding young chicks, the chick guard stage, penguin parents did not travel as far to find food as they did during the incubation stage. It is imperative that they return quickly to feed hungry chicks. However, some parents headed south in this stage rather than straight out to sea to forage - another pattern we haven’t seen before and perhaps related to an instinct that river mouths have higher nutrients and thus potential for prey fish. One individual travelled over 35km south from Karoro Beach to the Hokitika River mouth.  The resilience of our kororā populations on the West Coast is remarkable. But the results from this season also reflect their vulnerability.

Why long-term monitoring is critical to our research

This season’s findings highlight why ongoing foraging research is becoming increasingly important. Without our tracking data, the offshore conditions faced by kororā this season may have remained largely hidden.  Our study is helping to build a long-term data set that can demonstrate how changing marine conditions might influence breeding success, chick survival, colony growth or decline, and the future of kororā here on the West Coast.  As this data set grows, it will provide us with invaluable long-term insight into the environmental conditions and evolving selection pressures that kororā are facing in our changing oceans.  

A more detailed look

There are some key points of interest from the data we have obtained.  As you may remember, we trialled a new study site in 2023 and obtained data during the chick guard stage of breeding.  We moved our study focus there in 2024 and that year and in 2025, our Ranger, Lucy Waller, with her crew of volunteers, tracked kororā during both incubation and chick guard stages. The figures during incubation last year/last season were striking, with the maximum home range of over 120km, the penguin taking around 21 days to return.  Our earlier research from a Charleston colony indicated a more usual 25-30km home range.  As a result, it was a difficult season for this project, with many unsuccessful repeat checks to retrieve loggers on penguins staying out far longer than we had believed possible. Average dive depths that period were a low 3.6m but were very long, averaging 227m.  Each dive includes time at the surface between dives, that is dive and surface time before the next dive.  It seems that the penguins tracked during egg incubation in 2025 were travelling great distances to find food.  The maximum dive depth recorded for a kororā is an incredible 66.7m but the majority of their dives are understood to be under 30m. Tracking from our Charleston site did not have the benefit of the dive depth function, so we only have a limited data set by which to assess this.  We aim to continue to track kororā during egg incubation and chick guard stages and these future years of research will clarify average and extreme measurements. Diving efficiency (dive time over dive period including time at surface) is higher during the 2025 incubation stage than in 2024, but lower than average from the data collected at this site.  Lower efficiency indicates poor foraging generally with deeper dives.  However, in our data, we saw difficult foraging conditions during incubation more clearly indicated by the extreme distances of the foraging trips. Ideally foraging efficiency, a figure generated by the logger program, would give us a single figure to compare within or between seasons.  Unfortunately, it relies on the movement of the penguin, for example when quickly reaching for prey.  Interestingly, the loggers have become so sensitive that they now pick up the normal movement of the penguins' every wing stroke so this figure can not be relied upon.

 

ENSO, or the El Niño Southern Oscillation is tracked using an index, the Southern Oscillation Index. Extreme events of either El Niño or La Niña, are likely to impact penguin breeding success.

The Southern Oscillation Index or SOI

ENSO, or the El Niño Southern Oscillation, is tracked globally using an index, the Southern Oscillation Index, which measures surface air pressure fluctuations across the Pacific. Extreme events of either El Niño or La Niña, are likely to impact penguin breeding success wherever such climatalogical conditions impact foraging activity.

West Coast Penguin Trust observations

Through its penguin monitoring, the West Coast Penguin Trust has observations that relate closely to these climate phenomena. Firstly, in 2015, with a strong El Niño event, we saw tawaki chicks starve with breeding success close to zero at the Jackson Head study colony.  At the same time, our scientist, Dr Thomas Mattern, was tracking tawaki from the same colony, and found them foraging much further off shore and deeper than seen the previous year and since.  That high foraging effort is reported in his Tawaki Project report here. In 2022, breeding success of little penguins or kororā took a sharp nose dive with the peak of a 'triple dip' phase of La Niña events.  We halted our foraging study that year to avoid any extra pressure on penguins that were clearly stressed.  Around the same time, over 90% of the bull kelp at the Punakaiki Marine Reserve died off due to the prolonged marine heatwaves. Last year, the 2025 breeding season for kororā appeared to be adversely affected by a weak La Niña event, as we saw penguins expending very high foraging effort during the egg incubation stage and presumably the consequent poor breeding success from our study colony. So, what is going on and why can both sides of the Southern Oscillation Index impact penguin foraging and thus breeding success?

How may penguin foraging efforts be affected?

Curiously, both El Niño or La Niña events can result in warmer sea surface temperatures, and the natural assumption is that warm water drives penguin prey fish to cooler water, perhaps out of reach by distance or depth. However, the reality is that ENSO reorganises wind patterns and ocean circulation differently, affecting each penguin's specific prey, at their specific foraging depth, in their specific location. So we need go look at the differences between the two penguin species that call the West Coast home. Tawaki can dive to around 100m (with most dives to 20 or 30m) and, as Dr Mattern has found, over a few weeks can swim halfway to Antarctica and back, covering distances of 7,000km or more in one go. During the breeding season affected by El Niño at Jackson Head in 2015, they were ranging 100km offshore to find food, but that meant they were not only gone too long to feed chicks but probably returned without sufficient food for chicks. Kororā forage within around 20m of the surface most of the time, with rare maximum dives of around 30-40m.  They usually stay close to the breeding colony when raising chicks, 10–20km offshore and up to around 36km from home. During breeding, they pursuit-dive for prey generally in waters less than 100m deep.  Last year, we saw them going beyond 100km from home during egg incubation, into waters several hundred metres deep, putting stress on both penguin parents and sadly small chicks were found dead. We're essentially comparing a bird that can reach 100m depth against one constrained to roughly 40m depth. That's not just a size difference — it defines entirely different ecological niches, and entirely different vulnerability profiles.

Why La Niña hits kororā on the West Coast so hard

La Niña drives increased rainfall and storm activity on the West Coast. The effects compound in a way that specifically targets kororā's constraints. Thermal stratification. Prolonged warm La Niña sea surface temperatures create a strong, stable thermocline — a warm, buoyant surface layer sitting on colder water beneath. Nutrients and prey are pushed below this barrier. We believe tawaki can simply dive through it. Kororā, hunting mostly in the top 20m, are foraging in the warm, nutrient-depleted surface layer above where the fish have retreated. Sediment and turbidity. Turbidity caused by sedimentation can affect seabirds that hunt visually, including penguins. Sedimentation events are both cumulative — where sediment accumulates slowly over time — or catastrophic, where sediment is rapidly deposited, often following severe rainfall and storm events. La Niña's intense West Coast rainfall generates exactly this: rivers run brown, coastal waters turn turbid, and kororā — visual hunters — lose the ability to detect prey. Kororā may head for river mouths to take advantage of the high amount of nutrients running off the land, which fuel productive ecosystems, but this behaviour makes them vulnerable to increases in sediment after heavy rainfall. There's a cruel irony here: the very habit that draws them to productive river-mouth zones becomes a liability when storms hit, turning those areas into murky, sediment-laden water that defeats visual hunting.  During our foraging study in 2025, we saw two of the three birds monitored head along the coast to the Hokitika river mouth, perhaps supporting this theory. Kororā cannot escape such poor local conditions.

What about El Niño conditions?

In a strong El Niño event, the food web under the Tasman Sea can collapse — there is little food regardless of how far or deep a penguin can swim, which is why even the capable tawaki and their chicks may starve. In La Niña, the food isn't necessarily gone from the water column — it's below the thermocline, or hidden in turbid water. Tawaki, 60cm tall and weighing 4kg, can punch through both barriers. Kororā can't. It's not just strength, it's the physical architecture of the dive. A heavier, more streamlined bird with larger oxygen stores can reach greater depth. A 1kg bird, however perfectly adapted to its niche, simply cannot overcome physics to follow prey into water it cannot reach or see through. What's particularly concerning for the forecase major El Niño event is whether kororā — already stressed by the recent run of La Niña and heatwave seasons — will enter it in good enough condition. Body condition going into a bad season matters enormously for whether birds abandon eggs, successfully raise chicks, or simply survive.   We will continue to explore what ENSO means for penguins on the coast. In the meantime, research shows that while ENSO remains a naturally occurring cycle, human-caused climate change is supercharging both El Niño and La Niña events, making them more extreme. Increased greenhouse gases and background warming are driving stronger temperature swings, more volatile rainfall patterns, and longer-lasting extreme events worldwide. So we must continue to do our bit, however small - it all adds up, to reduce our carbon footprint through our travel, energy use and purchasing power.

A little bracelet with a big heart - one small bracelet, one big mission

I was recently given a lovely stone bracelet, and, it turns out, my Fahlo penguin bracelet was much more than a bracelet! Fahlo partners with nonprofits to both foster curiosity for wildlife and their conservation and to fund conservation efforts to protect our planet's most at-risk animals and their habitats. Supported conservation programmes include Polar Bears International, Save the Elephants, Sea Turtle Conservancy, Ewaso Lions as well as several others and, for us, importantly, the Global Penguin Society. Find all the progammes and species supported by Fahlo here. The Global Penguin Society (GPS) is the first and only international organisation dedicated to protecting all 18 penguin species. Through scientific research, education, and community management, GPS continues to support penguin conservation and protect the coasts and oceans they inhabit. The penguin bracelet helps Fahlo further this GPS mission, tracking Magellanic penguins in South America. The West Coast Penguin Trust is supported by the Global Penguin Society's man in New Zealand, our scientist, guide and advisor, Dr Thomas Mattern. Everything is connected!  And if you'd like to buy bracelets for yourself or as gifts, supporting one or more of the various essential conservation programmes as you do, you can find them at or from Wellington Zoo via the links below, thus helping them (who also help us!) and the species!  Another wonderful connection! Fahlo penguin bracelet - follow this link All Fahlo products - follow this link Once you have your bracelet, you will be able to track an animal on its journey.  Simply scan a Qr code that comes with the bracelet and you will learn about the penguin or other species, get their picture and you can follow them on the exclusive tracking map.  My Magellanic penguin is off the coast of Montevideo as I write, amongst many others being tracked by the Global Penguin Society.

 

New penguin encounter centre opened 17th October 2025

5 November 2025 An exciting new opportunity to meet little penguins / kororā - Ambassador Kororā Encounter - opened at the West Coast Wildlife Centre in Franz Josef last month.  The West Coast Penguin Trust has been privileged to be connected to the ideas and plans for a penguin encounter opportunity here for a few years and were honoured to be at the official opening. We're delighted that our work is featured on a couple of panels at the new addition to the Wildlife Centre, a fixed panel and another that scrolls through some photos.  Visitors are invited to make a donation for community conservation of penguins, kiwi and tuatara - the three species on display at the centre, promoting conservation of their relatives in the wild.  Every year, donations will be shared between our trust and others working with kiwi and tuatara. The 'ambassador' penguins are birds that would not have survived in the wild, generally due to injury.  Here, they can live out their lives in comfort and be ambassadors for their species. The event was opened by Paul Madgwick and other members of Te Rūnanga o Makaawhio with a Pōwhiri, followed by a speech by centre owner, Richard Benton, who, together with his wife Sherilee, have developed this wonderful new centre, benefitting penguins and the region.  DOC Director Owen Kilgour added more conservation focus and noted the value of the work Richard and the West Coast Wildlife Centre have done for rowi and Haast tokoeka kiwi for many years and the strong partnership with DOC, welcoming the additions of penguins.  Development West Coast CE, Heath Milne, welcomed the significant investment in tourism on the West Coast while giving conservation a priority, focus and stronger profile. And West Coast - Tasman MP, Maureen Pugh, had the honour of welcoming the new attraction and then cutting the ribbon with Richard.  She also emphasised the importance of conservation - of our native species and their habitat, which was great to hear. Here's a news story about the ambassador penguins: https://www.facebook.com/reel/654336360889403 And photos below are from the opening event, including speeches, ribbon cutting, our panels, the donation panel, the opening event plaque, the penguins of course, and even ice penguin sculptures to add to the occasion.  In place of red carpet, there was blue carpet, and the staff wore blue bow ties.  The blue of little blue penguin was celebrated everywhere! Put a visit to the ambassador penguins and their wonderful new home on the to do list, for you, and your family and friends! https://wildkiwi.co.nz/the-attraction/penguin

Checks and repairs of the fences have been carried out by volunteers and rangers

September 2025 The first trial penguin protection fence was installed just south of Punakaiki in 2013 and the main one for the Coast Road was constructed north of Punakaiki in 2014.  A smaller one was added near Seal Island in 2015, the newest penguin protection fence was installed on the northern outskirts of Hokitika in 2021 and two new sections were added north of Punakaiki in 2023 and 2024. While materials were chosen that would stand up to the harsh coastal conditions, those same coastal conditions are conducive to plant growth!  Occasional checks of the fences have been carried out by volunteers and rangers so that any maintenance needs can be identified and remedied.  The never-ending need for maintenance is managing the vegetation that can grow through the fence, for example gorse, blackberry and hydrangea, pushing it to breaking point in places, or flop over causing damage from the weight of rank grass, rushes and weeds such as montbretia. Volunteers recently spent a few hours tidying up the main fence along Woodpecker Bay north of Punakaiki so a big shout out to them - thank you Fiona, Jony, Reef, Katrina, Mandy, Marty, Teresa and Deb!  Flax had been pressing down on the fence, but now the fence has been freed up by these wonderful volunteers - and they picked up a fair bit of rubbish too. Volunteer Natassja Savidge has offered to check and help maintain the Hokitika penguin protection fence and joined Ranger Lucy Waller and Manager Inger Perkins in May to inspect the length of the fence.  Some minor issues were found but the main finding was the extent of the vegetation growth that was damaging the fence in places.  Big thanks to Natassja! Recently, volunteer Karen Hitchcock joined trust manager, Inger Perkins, for weeding along a section of the Hokitika fence and continued alone the following weekend.  Karen is host at the Fitzherbert Court Motel in Hokitika, just a mile or so away.  With Conservation Week in the news, 'naturing' on the agenda and Qualmark Bronze Accreditation, Karen decided to combine the three and offer time to help with penguin conservation.  A Bronze business must meet all Qualmark’s expected standards in the Sustainable Tourism Business criteria.  It identifies a business with high professionalism, an awareness of its impact on the environment and a customer-centric approach. Gorse, grass and montbretia were the main culprits, and a good start was made clearing them from the fence.  Fast-growing gorse at a strainer post had snapped the top fence wire, which will need fixing but at least the fencer will be able to get to the fence.  A big thank you to Karen!! The Hokitika penguin protection fence was kindly paid for by Westland Milk Products and they generously continue to support penguin conservation efforts.  The fence follows the Westland District Council's fence on the coastal side of the sewage ponds and then follows fencing along the railway line.  We are fortunate that both WDC and Kiwirail maintain their own fences and weed control helps keep the penguin fence clear. More volunteer opportunities will be coming soon!

West Coast New Zealand penguin fossil discoveries tell us about penguin evolution