The Fiordland penguin or tawaki (Eudyptes pachyrhynchus) is the only crested penguin species to breed on the New Zealand mainland and, therefore, the only crested species in the world that lives in relative proximity to human settlements. Although only breeding in remote parts of the mainland and satellite islands in South Westland, Fiordland and Stewart Island that are mostly difficult of access tawaki are exposed to many anthropogenic influences including inshore fisheries, unregulated tourism, and pollution, that other crested penguins are not. The species is believed to have undergone a significant decline in recent decades, although it is unclear whether this trend continues. Currently, the official population estimates for the species range between 5,500 and 7,000 mature individuals¹, although recent surveys suggest that tawaki are more common than generally thought. Until recently little was known about the species marine ecology; diet studies carried out in the 1980s found that the penguins fed predominantly on cephalopods and krill in an open coast environment, while fish dominated the diet in the Foveaux Strait region. Studies conducted since 2014 have significantly expanded our knowledge about the species.

The first detailed account of tawaki was published by John Warham² which primarily focussed on terrestrial aspects of species biology. A comprehensive, encyclopaedic review was compiled by Marchant & Higgins³ which cites several sources that cannot be accessed today. A report summarised the results of the Department of Conservation’s monitoring programme and identified several issues related to survey design⁴. More recently a review of available knowledge largely based on unpublished reports was compiled by Mattern⁵; that chapter serves as basis for this review.

Research and conservation priorities for tawaki have been listed in Taylor⁶ and Mattern⁵. Both stress the urgent need for a better understanding of the species’ demography and marine ecology in order to improve conservation outcomes.

Here, we focus on aspects of the species’ biology that are deemed most important for conservation. Below we list topics and relevant publications that will not be discussed in detail in this review.

• Genetic & Social monogamy⁷
• Vocalisation⁸
• Egg formation⁹ & reproductive endocrinology¹⁰
• Brood reduction^11,12

The Department of Conservation lists tawaki as ‘Nationally Vulnerable’ (criteria D, 5,000-20,000 mature individuals, predicted decline 10-50%¹³). The IUCN red list classified the species as ‘Vulnerable’ due to the species’ small population that underwent ‘rapid decline over the last three generations’¹.

Fiordland penguins have only recently been recognised as distinct from the Snares penguins (Eudyptes robustus). In the 1970s, the Checklist of New Zealand Birds considered Snares, Fiordland and even Erect-crested (E. sclateri) penguins as conspecifics¹⁴. This was disputed due to morphological and ecological differences between each taxa^15–17. More recently, studies that examined relationships using morphology, protein data, and mitochondrial and nuclear DNA have all supported the recognition of three separate species^18–21. Nevertheless, a review of the taxonomic status in 2008 still considered Fiordland and Snares penguins as conspecific²². Consultations by Birdlife International in 2014 led to the calculation of the Tobias score²³, which demonstrated that tawaki and Snares penguins should be considered separate species (see http://bit.ly/tawaki-tobias-score).

The breeding range of tawaki is limited to the south-western coast of New Zealand’s South Island where the penguins occur in lose colonies in coastal rainforests, sea caves or under rock boulders of rocky shores. Mattern⁵ provides an extensive list of tawaki breeding sites that have been surveyed in the past. Penguin numbers at 43 colonies have been estimated sometime between 1991 and 2009. On the mainland, tawaki range from Heretaniwha Point near Bruce Bay, South Westland (S43.59, E169.55) to Coal Island in southern Fiordland (S46.12, E166.63). In Foveaux Strait, the penguins breed on Solander Island/Hautere, Codfish Island/Whenua Hou, Stewart Island/Rakiura and its outliers⁵.

Figure 1. Tawaki in the Harricon Cove, Milford Sound/Piopiotahi breeding colony which features a typical rainforest setting. (Photo: Thomas Mattern)

Tawaki have been recovered from a number of natural fossil deposits and archaeological middens throughout coastal New Zealand, and there are numerous publications that summarise findings^24,25. Although difficult to distinguish from other crested penguins (and even Megadyptes penguins), most prehistoric specimens found to date on the New Zealand mainland were tawaki²¹. The large number of bones excavated from many sites in coastal New Zealand indicate that tawaki have probably inhabited New Zealand at least since sea level stabilised, 6000 years ago.

It has been suggested that historically tawaki had a wider distribution with breeding sites in the north of the South Island and potentially even the lower North Island⁵. However, recent studies seem to contradict this idea. A study looking at genetic information in prehistoric bones, museum skins and blood samples found that the genetic diversity of tawaki does not suggest any substantial range restriction over the last thousand years²¹. Moreover, while historic samples were obtained from adult penguins found as far north as the North Cape, no juvenile bones or eggshells were excavated from the upper South Island or lower North Island. This may indicate that bones from these northern sites originate from vagrants rather than resident breeders. This hypothesis is further supported by a recent examination of the pre-moult dispersal in tawaki²⁶. The authors argue that genetic predisposition may drive the penguins to travel to the sub-Antarctic front some 2,000 km south of New Zealand and that the current range of the species likely represents the geographic extremes at which this strategy is viable.

Outside the breeding season, recent satellite tracking data suggests that tawaki spend most of the time prior to their moult in sub-Antarctic waters between 1,500 and 2,500 km south-east of the South Island²⁶. Outside the breeding season, tawaki (mostly moulting birds) have been observed around most of the South Island, but also on the Snares/Tini Heke, Auckland, Campbell and Macquarie Islands. They are common visitors to Tasmanian shores and are occasionally reported from southern West Australia all the way to New South Wales; there is one unconfirmed report of a tawaki on the Falkland Islands³. Where tawaki go after completing the moult is currently being investigated; it appears that birds tend to show similar dispersal movements to the pre-moult period (Mattern, unpublished data).

A series of distribution surveys were carried out between 1990 and 1995 that covered most of the species’ current breeding distribution^27-31. To date, these surveys represent the only attempt at an estimate of tawaki numbers. The authors concluded that there were 2,500-3,000 breeding pairs³¹. However, methodology and scope of these surveys made undercounting of penguins highly likely⁵. Using accounts published prior to 2016, a review of Fiordland penguins for the IUCN Red List concluded that there are between 2,500 and 9,999 mature individuals¹.

More recently, nest counts carried out in Fiordland³² and South Westland 33 found considerably more penguins than reported by the survey 20 years earlier. A ground survey conducted in Milford Sound/Piopiotahi in the spring of 2016 found 77 nests and resulted in an estimate of between 130 and 150 breeding pairs in this fjord³², a stark contrast to the 9 nests found in the 1990s²⁷. Similarly, nest searches carried out in the spring of 2014 between Cascade River and Martins Bay found a total of 835 nests³³; the previous estimate for that region was just 150 nests³¹.

The estimates from the 1990s and recent surveys either indicate significant undercounts in the earlier surveys or suggest an increase in tawaki numbers in the past 20 years. McLean et al.³¹ themselves caution readers to consider their counts to be “a minimum estimate” due to the logistic constraints of their survey. So, undercounting certainly contributes to the apparent differences in penguin numbers between the 1990s and the recent surveys.

Most recent estimates of tawaki numbers^32,33 can be used to adjust counts from the 1990s surveys. Along the southern West Coast Robin Long³³ counted 850 breeding pairs while McLean et al.³¹ only recorded 150 pairs in the early 1990s suggesting a population increase (or previous underestimation) of 566%. Similarly, the recent nest counts provided for the Milford Sound population of 77 breeding pairs³² compared to 9 breeding pairs recorded there in 1990s⁵ would represent 770% increase in numbers. Assuming that much higher penguin numbers apply to the species’ entire breeding range and applying a conservative adjustment factor of 500% to the IUCN numbers, the current population size of tawaki could range between 12,500 and 50,000 mature individuals.

Yet, a recent paper analysing tawaki population trends using data from DOC’s monitoring programme that operated from 1990 to 2010 concludes that the tawaki population is still in decline³⁴, in line with the assessments in Taylor⁶ and the IUCN red list¹.

However, other observations seem to suggest numbers have actually increased:

• Beach counts (n=1,270 counts) of tawaki commuting between the sea and their breeding colonies at a beach north of Haast conducted over the past 20 years showed an increase in penguin numbers from an average 8 birds per observation in 1996 to 12 birds in 2017 (Gerry McSweeney, unpubl. data)
• Other credible observers have noted an increase in tawaki numbers in recent decades. Several tourist boat skippers operating in Milford Sound during the past two decades believe that penguin numbers have increased; as do some fishermen operating in Dusky Sound. Tawaki were seldom seen along the north-east coast of Stewart Island in the 1970s (K.-J. Wilson, pers. obs.), where in 2005 and 2014, they seemed to be omnipresent, both at sea as well as on land (Mattern, pers. obs., see https://www.tawaki-project.org/2014/11/07/little-cave-men/).
• Recently tawaki have attempted to breed in the Catlins which may suggest a range expansion for the species³⁵.
• Genetic analyses of 72 historic and recent tawaki samples found no evidence for significant changes in population size for tawaki over last thousand years²¹.

The assumption by Taylor⁶ that numbers were in decline was based on observations from a single site, Open Bay Islands. Between 1988 and 1995 the tawaki population on the island reportedly declined by 33%³⁶. However, during that period research that involved handling of eggs shortly after laying and daily nest checks was undertaken on the island 11. As tawaki are perhaps the most timid of all crested penguin species³⁷, that intensive research may have contributed to this apparent decline.

In this light it seems doubtful that negative population trends observed at Open Bay Islands are representative across the species’ entire range. The information available does not allow us to determine population trends with any degree of certainty.

The diverse breeding and foraging habitats occupied by tawaki are reflected in notable differences in their ecology and demographic parameters. For example, while the breeding success and number of breeding tawaki from Jackson Head, West Coast was significantly impacted first by a strong El Niño in 2015 and then by an invasion of stoats (Mustela erminea) in 2016, the situation in Milford Sound was diametrically different with above average breeding success and stable nest numbers^38,39. Similarly, breeding success was found to be high and penguin numbers stable at Codfish Island/Whenua Hou in both 2016 and 2017³⁹. At some sites, terrestrial predators can have serious impacts on breeding success while at other sites these predators are absent³⁹. Predation by stoats varies season to season and site to site. At Jackson Head no predation events were recorded during the 2014, 2015 and 2017 seasons, yet all breeding attempts failed in 2016 with stoat predation being the likely main cause; at the same time no predation events were recorded at their Gorge River study site 45 km away⁴⁰.

Figure 2. Impenetrable tawaki habitat in a kiekie patch on Breaksea Island. Yellow arrow indicates tawaki nest. (Photo: Thomas Mattern)

Tawaki are notoriously difficult to monitor. They mostly breed in inaccessible places such as in thick kiekie (Freycinetia banksia) vegetation, narrow rock crevices or labyrinthine caves making it very difficult to conduct reliable counts ^5,32 (see also https://youtu.be/Z2Qc6SrGDjc). Observer experience and endurance is of utmost importance to achieve reproducible monitoring results and can significantly affect the reliability of ground counts. For example, on three consecutive surveys an increasing number of nests were found in previously overlooked areas even though the observers were highly experienced and knew the terrain extremely well^33,41,42.

Overall, it is unlikely valid conclusions about population trends can be drawn from ground counts. The penguins’ cryptic breeding habits and often impenetrable breeding habitat effectively prevents the application of traditional nest searches to obtain reliable information on population trends. Instead, a focus on determining key demographic parameters (i.e. survival rates, fecundity) from mark-recapture studies across their varied habitat should be used to assess population trajectories.

Between 1990 and 2010 the Department of Conservation conducted annual nest counts at various sites ranging from Codfish Island/Whenua Hou, Foveaux Strait to Monro Beach, South Westland³⁴. More recently, double counts (the count repeated by a second team two days later) at selected sites were employed to minimize the potentially substantial observer error from the single counts prior to 2010; this indeed delivered more reliable population estimates³⁷. However, limited resources have since led to a cessation of the DOC monitoring programme.

Based on the monitoring data, Otley et al.⁴³ determined core demographic variables for the species. Survival probabilities were calculated to be around 89% for adult penguins, with juvenile survival – defined as survival until first breeding – estimated at 77%. Combined with a mean breeding success of 0.61±0.02 chicks per pair, tawaki core demographic variables appear to be higher than for most other crested penguin species^44–46.

The Tawaki Project has researched the marine ecology of tawaki at three sites – Jackson Head, Milford Sound and Codfish Island/Whenua Hou – and in conjunction with this work has monitored breeding success. While breeding success at Jackson Head varied due to the aforementioned impacts of El Niño and stoat invasion between 0.12 and 0.94 chicks per pair (2014-2017), reproductive efforts of tawaki from Harrison Cove, Milford Sound were consistently high (0.8 - 1.1 chicks per pair, 2015-2017); breeding success was similarly high at least until crèching on Codfish Island/Whenua Hou (Mattern et al. unpubl. data). However, as with ground counts, determination of breeding success is difficult as chick survival can only be determined with certainty until the crèching stage during which chicks are highly mobile and often impossible to locate.

Except for a few open nests, tawaki are cryptic breeders that prefer to nest in inaccessible locations. Along open coast sites like Jackson Head, the penguins tend to breed in dense, impenetrable kiekie shrub often in small clusters of nests². At Gorge River, the penguins breed in a more open forest setting, primarily under tree roots or fallen trees, in amongst kiekie or tangles of supplejack (Ripogonum scandens)³³. In Harrison Cove, Milford Sound less than a third of all nests are under rock overhangs or upturned tree roots. Most of the nests are in rock crevices or in cavities and caves under rock falls. At Sinbad Gully, Milford Sound, the penguins occupy a steep slope that is dominated by windfall of rimu (Dacrydium cupressinum) and other large trees; a few kilometres up the fjord, the majority of the penguins nest in an extensive warren under remnants of a glacial moraine³². On Codfish Island/Whenua Hou, the penguins breed in dense tree fern groves, mainly in dug out, deep burrows in the soft peaty soil or in deep hollows under tree roots, while along the north-east coast of Stewart Island the penguins breed in sea caves and fissures in cliffs only accessible from the sea (Mattern, pers. obs.).

Nests usually consist of shallow bowls lined with twigs and stones (Fig. 3).

Figure 3. Tawaki nest in Harrison Cove, Milford Sound/Piopiotahi (Photo: Thomas Mattern)

John Warham² published the first and seminal account of tawaki breeding biology, although his observations were largely limited to a single site, Jackson Head. In the late 1980s and early 1990s, St. Clair^11,47 focussed on site fidelity and incubation behaviour in an effort to decipher the crested penguins’ obligate brood reduction. Some aspects of the breeding biology of tawaki are also touched on by Ellenberg et al.³⁷.

Mattern⁵ provides a detailed summary of the species breeding biology thus only a condensed account is presented here.

Tawaki return from three months at sea to their breeding colonies in mid-June, with the majority of penguins returning to the nest sites they used in the previous year; about two-thirds of the penguins reunite with their previous partner^2,47. Egg laying occurs over a 10-day period in late July and early August, the clutch size is two with the eggs being laid 3-6 days apart. As with other crested penguins, the first-laid A egg is smaller than the second-laid B egg, although the size difference is less marked than in other crested penguins⁴⁸. While largely synchronized within colonies, the timing of egg laying seems to vary between sites by as much as 2-3 weeks³⁷.

In tawaki, the roles during incubation are the reverse of that in other crested penguins. The pair spends the first 5-10 days after the B-egg is laid together at the nest, the female then leaves on a two week long foraging trip²; in all other crested penguins it is the male that makes the first foraging trip⁴⁸. After the females return, the male penguins leave for up to two weeks usually returning a few days prior to egg hatching. Like all other crested penguins, tawaki are considered obligate brood reducers that generally only raise one chick. However, McLean et al.⁷ noted that in years when food is abundant, up to 12% of tawaki pairs can fledge both chicks. Some tawaki breeding in Milford Sound/Piopiotahi and on Codfish Island/Whenua Hou can also fledge both chicks^38,39,49.

Eggs hatch throughout September, 31-36 days after the B-egg is laid^2,11. In nests where only one chick is raised, the smaller chick that hatched from the A-egg usually dies within a week after hatching, severely disadvantaged by smaller body size compared to its sibling. Both Marchant & Higgins³ and St Clair⁵⁰ state that 50-60% of nests only hatch one egg; the rate of egg loss was lower during recent studies^38,39,49,50. The male penguins guard the chicks for up to three weeks, while the female is the sole provider of food to her offspring².

From early October, chicks may form small crèches that are often guarded by one male penguin. Mostly, however, both male and female undertake foraging trips at this stage. It is mainly the female that feeds the chicks, although males increase their food contribution closer to fledging². Chicks fledge between mid-November and early December. The parents leave on their pre-moult foraging trips shortly after the chicks have fledged.

Satellite tracking of adult tawaki from Gorge River, South Westland during the pre-moult dispersal November 2016 to February 2017 found that the penguins travelled extraordinary distances compared to other crested penguins at this stage of the annual cycle²⁶. The birds left their colonies between mid-November and early December with those birds departing earlier travelling towards the subtropical front some 800-1000 km south of Tasmania, while penguins leaving in December ventured further south to the sub-Antarctic front southeast of Macquarie Island. Return journeys ranged from 3,500-6,800 km during the 8-10-week sojourn at sea before returning to the mainland to moult. Of the five birds that could be tracked for the entire trip, three penguins returned to their breeding colony at Gorge River to moult. The remaining two birds moulted at Dusky Sound and Sutherland Sound, respectively. Warham (1974) states that penguins generally return in mid-January and early February to moult. The satellite tracking study found that some birds may return as late as the end of February²⁶.

Figure 4. Pre-moult dispersal of tawaki from Gorge River, Southwestland December 2016-February 2019 as determined by satellite tracking; graph adapated from Mattern et al. ²⁶

Although it has been stated that tawaki generally return to their breeding colonies to moult², this seems to vary between sites. For example, tawaki colonies on the western side of Jackson Head were found to be virtually devoid of moulting penguins or sign that penguins had recently completed moulted there in February and March 2014-2018 (Mattern, pers. obs.). Instead, moulting tawaki are commonly seen in the nearby settlement of Neils Beach and along the coastal road to Jackson Bay (Geoff Robson, Greenstone Helicopters, pers. comm.). In Harrison Cove, Milford Sound/Piopiotahi (Fig. 5), on the other hand, there seem to be more penguins moulting there than are present during the breeding period. On Codfish Island/Whenua Hou, the colonies seem to be largely occupied by moulters that had bred there months earlier (Mattern, pers. obs.).

Replacement of feathers takes roughly three weeks; the penguins then depart on their winter sojourns².

Figure 5. Tawaki undergoing the moult in Harrison Cove, Milford Sound/Piopiotahi (Photo: Thomas Mattern)

Until recently the only information available on the marine ecology of tawaki was derived from two studies of their diet in the early 1980s^52,53. Prey taken varied between regions with arrow squid (Nototodarus sloani) (relative biomass contribution: 85%) and krill (13%) dominating the diet of tawaki from Martins Bay, Fiordland⁵³, while fish (85%), especially larval stages, were most important for penguins from Codfish Island/Whenua Hou, where cephalopods and crustaceans were minor constituents of their diet⁵². More recently, the prey composition of penguins from Jackson Head was investigated by identifying prey DNA in penguin scats (Julie McInnes et al., unpubl. data). Fish were the most common prey category (frequency of occurrence: 75%) followed by cephalopods (15%) and krill (10%). Interestingly, jellyfish DNA was found in several of the samples which could indicate that, like yellow-eyed penguins⁵⁴, tawaki may feed on fish larvae associated with jellyfish.

Since the 2014 breeding season, The Tawaki Project has studied the foraging behaviour of chick rearing tawaki at sites representative of the species’ varied marine habitat, i.e. Jackson Head, South Westland (continental shelf); Harrison Cove, Milford Sound/Piopiotahi (fjord); and Codfish Island/Whenua Hou, Foveaux Strait (shallow, coastal). The at-sea movements and diving behaviour differed significantly between these sites.

At Jackson Head, the penguins generally foraged between 10 and 50 km offshore, mostly north-west of the colony. Foraging ranges and trip durations were influenced by prevailing environmental conditions travelling further during longer duration trips during years dominated by southerly winds (e.g. El Niño conditions) while north-westerly winds appear to create more favourable foraging conditions closer to the coast (https://youtu.be/1c4B9sdL8Y0?t=12m50s).

During three years of research in Milford Sound/Piopiotahi, there has been just one observation of a penguin leaving the fjord. All other data clearly show that while feeding chicks tawaki forage exclusively within the fjord; most of the foraging activity occurring just 1-4 km from their breeding colony. It is noteworthy that the penguins tend to spend most of their time along the northern side of the fjord within one of New Zealand’s few marine reserves (Fig. 6).

Figure 6. Tawaki undergoing the moult in Harrison Cove, Milford Sound/Piopiotahi (Source: http://bit.ly/milford-sound-MPA)

Tawaki from Codfish Island/Whenua Hou tracked in the 2016 and 2017 breeding seasons and have shown two types of foraging strategies. Birds either forage very close inshore following the coast line, presumably targeting prey in the kelp forests, or they travelled 20-30 km to the west where the shallow Foveaux Strait seafloor drops away into the deep-water Solander Trough (Mattern & Ellenberg 2017; Mattern et al. unpubl. data).

Overall, it appears that penguins from South Westland show the greatest foraging effort and are most susceptible to environmental perturbations. What this means for tawaki breeding along the open Fiordland coast – especially populations in interface regions where birds can choose to forage inside or outside the fjords (e.g. Breaksea Island, Shelter Islands) needs to be addressed.

Diving behaviour of tawaki is also being studied as part of The Tawaki Project. A maximum dive depth of 99 m has been recorded for a female from Jackson Head. However, most dives are considerably shallower, seldom exceeding 30 m, indicating that tawaki mostly feed close to the surface. Body acceleration has also been recorded which allows a more detailed analysis of the penguins’ diving behaviour⁵⁵. Detailed analysis of all diving data is pending.

Although Warham² states that seals are unlikely to play an important role in predation of tawaki, recent observations show that tawaki are taken by fur seals (Arctocephalus forsteri) in Milford Sound (Daniel Crook, Southern Discoveries, pers. comm.). Moreover, groups of fur seals apparently undertaking coordinated pursuit of tawaki have been observed at the entrance of the fjord (Turgut Ortabas, Southern Discoveries, pers. comm.). Dead tawaki have been found on beaches with obvious signs of shark bites (Fig. 7, Mattern, pers. obs.). However, beyond this little is known about predation of tawaki at sea.

Figure 7. Dead tawaki found on a Southwestland beach 2014 with rows of laceration from shark bites running along one flipper and its torso (Photo: Thomas Mattern)

On land, stoats have a significant impact on breeding success during some years at some locations. At Jackson Head and Gorge River they have been observed to take eggs and kill tawaki chicks^39,40. In the 2016 breeding season, an invasion of stoats apparently caused almost complete breeding failure on the western side of Jackson Head. Yet in 2014, 2015 and 2017 no predation events were recorded at that colony⁴⁰. Conversely at Gorge River, 45 km away, where nests were also monitored by motion activated cameras, one egg was taken by a stoat in both 2014 and 2015 but no predation events were recorded in 2016, the year stoats caused breeding failure at Jackson Head⁴⁰. The 2016 breeding season followed a mast event in the podocarp forests near Jackson Head and the stoat invasion may have been a result of stoats moving onto the headland as food availability in the neighbouring forests declined. Disappearance of chicks at Jackson Head in 2016 only ceased after traps had been deployed and three stoats killed. A network of self-setting traps has since been established on Jackson Head. The effectiveness of ongoing predator control by the Wilderness Lodge Moeraki and the Department of Conservation at one site north of Haast using brodifacoum bait stations (until 2006) followed by regular 1080 drops is likely to be linked to increasing penguin numbers determined from beach counts during the past 20 years (Gerry McSweeney, pers. comm.).

The endemic weka (Gallirallus australis) preys upon tawaki eggs and chicks^6,12,50. Weka have been introduced to some islands where tawaki breed including Open Bay Islands and Solander Island⁶. However, Mattern⁵ suggests that if the impact of weka was severe, tawaki populations at those sites would probably have declined in the immediate years following weka introduction; yet both tawaki and weka remain common on both.

Taylor⁶ suggested rats (Rattus sp.), and brushtail possums (Trichosurus vulpecula) to be potential predators of tawaki eggs and chicks. Rats, mice and brushtail possums are present in the Jackson Head and Gorge River tawaki colonies, they frequently pass by and occasionally investigate tawaki nests but none have been seen preying on tawaki eggs, chicks or harassing adult penguins⁴⁰. Rats and possums may scavenge expelled eggs and dead chicks (Mattern, pers. obs.). Dog attacks have been reported at some accessible breeding sites including Jackson Head (Jacinda Amey, DOC Haast, pers. comm.).

Human disturbance through research and unregulated tourism is believed to have a significant impact on tawaki⁶. While people’s presence at landing sites do indeed cause delays when penguins want to come ashore, the penguins seem to be more tolerant to research interactions than previously expected⁵¹. This is presumably due to the penguins’ attachment and investment in their nest rather than a greater tolerance of disturbance³⁷. Unregulated visits to the colony at Munro Beach, South Westland has apparently led to a decline in the numbers of tawaki breeding there although robust data to support this is lacking. Along the Jackson Bay Road, tawaki occasionally get run over by vehicles, particularly during the moult (Geoff Robson, Greenstone Helicopters, pers. comm.)

Comprehensive summaries of threats have been published in Mattern 5 and Otley et al. 34, however neither provides a threat level ranking or considers regional differences. In this report, we rank threats into major, medium and minor categories and provide a regional context.

Environmental disasters

Pollution

Fisheries interactions

Marine predators

Terrestrial predators

Disease

Climate change

Human interactions

While recent research has advanced out knowledge about tawaki, the species remains one of the least known of the world’s penguins. The demographic work in particular has raised more questions than answers. It is imperative to develop enhanced monitoring methods to get a better understanding of population trends.

1. Population monitoring

2. Marine Ecology

We are grateful to Tess Cole, Helen Otley, Gerry McSweeney and Dave Houston for valuable feedback and criticism of earlier drafts of this account. This review was funded by the T-Gear Charitable Trust and the Birds-New Zealand Research Fund - thanks so much for supporting our work. We are especially grateful to Peter Gaze for his support and interest throughout.

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