New Zealand Brown Teal

New Zealand Brown Teal – An Almost Forgotten Species

by F.Neil Hayes QSM – Brown Teal Conservation Trust

Photo courtesy Lynda Feringa and the Wairarapa Time Age

THE RACE TOWARDS EXTINCTION
Brown teal evolved in an almost totally predator free New Zealand environment and in a landscape which contained vast tracts of every type of wetland.
Whilst the destruction/modification of New Zealand wetlands, together with excessive hunting, impacted heavily on brown teal survival, the greatest factor influencing the brown teal’s race towards extinction has been the importation and spread of predators – firstly with rats, and then with cats, ferrets, stoats, weasels and hedgehogs; coupled with the ever-increasing population growth of the harrier hawk, which benefited from protective legislation introduced in 1986. Plus the clearance of native forests. In addition, both feral and domestic dogs have assisted the decline/demise of teal at a number of critically important sites.
When humans first arrived in New Zealand (research is ongoing to determine when this actually occurred) brown teal were believed to be the most abundant species of New Zealand duck and were found throughout the country’s vast wetlands. But with the arrivals of Europeans (accompanied by cats, ferrets, stoats, weasels, hedgehogs, guns, etc) the brown teal population began a significant period of decline, a decline that accelerated from the 1950’s onwards. In spite of gaining total protection in 1921 the population plummeted dramatically from c2,500 in 1988 to a level where the species is now one of the world’s most endangered ducks; perhaps the world’s fourth most endangered, and by 1999 was in imminent danger of premature extinction, with only c750 surviving – and with the predicted time for total extinction being 2015.
However, there is now clear, compelling and conclusive evidence to show that brown teal can be saved from premature extinction - by eliminating all predators at key sites, by ensuring pristine habitat, by ensuring an adequate food chain at these habitats, and by ensuring that the whole programme is well supported by a soundly based management structure, as well as a soundly managed captive breeding programme – remembering that no species of rare waterfowl has been saved without a major captive breeding component.
For many years brown teal protagonists have attempted to promote the philosophy that predator control at key sites will, in the short-term, rapidly retard the decline, and in the medium-term teal populations will expand. In the long-term such activity, in association with habitat protection, creation, enhancement, seriously dedicated management, plus a major captive breeding programme, will eventually result in brown teal populations dramatically expanding and brown teal being removed from the endangered list.
The successful survival and breeding of captive reared brown teal released on to a number of New Zealand’s predator free offshore islands clearly endorses this philosophy – clearly supported by the fact that the ten pairs of teal released onto Kapiti Island in 1969 resulted in a self-sustaining population on the island.
In simple terms, you provide brown teal with good habitat and a protected environment and they live long healthy productive lives – just as we have seen with captive brown teal, a number of which have lived for 16, 17, 18 and 22 years, with the record being just over 24 years!



A brown teal flock at Parekura Bay, just south of Russell in New Zealand’s Bay of Islands, in 1984. For decades this site was an important brown teal roost site and c100 birds could be regularly seen there. But by 1996 there were no brown teal present – all eliminated by predators.

PREMATURE EXTINCTION
Many environmental experts have long promoted the philosophy that extinction is a biological certainty and an intrinsic part of the evolution process; with natural causes being the main route to extinction — earthquakes, eruptions, floods, massive natural environmental changes, competition for food, and so on. Historically this is, of course, very true, but in the past c100 years the path towards extinction for many bird and animal species has undoubtedly been hastened by the massive growth in the world’s population, by our poor respect for the natural environment and for the world’s wild animals and birds; together with our generally abysmal understanding of the environment and how to successfully manage the world’s natural resources. Nothing could be truer than with the New Zealand situation, where New Zealand comfortably holds the world record for a country with the highest number of endangered endemic birds - none of which have become endangered by ‘natural causes‘. Remembering that these endemic bird species evolved in a predator-free environment, these species have all become endangered through mans’ interference with nature - by introducing predators, by introducing competing bird life, by destroying habitat, by drastically modifying/disturbing habitat, and by excessive hunting. Many are in grave danger of ‘premature extinction’.
All of these accumulated factors have lead to the precarious state of many New Zealand bird species, with brown teal suffering more than any other endemic mainland waterfowl species.



BROWN TEAL BEHAVIOUR
Besides being endemic to the New Zealand landscape, it is mainly the behavioural characteristics of brown teal that set it apart from all other species of dabbling duck, and in a class of its own.
These behavioural characteristics can be summarised as follows
• Nocturnal behaviour
• Monogamous relationship
• Murderous nature of an established pair (In 1960 when Peter Scott received three
brown teal at WWT Slimbridge he said that he hoped New Zealander’s were not of
a similar nature!)
• Long-term parental attention provided to their progeny by both parents
• Great climbing ability
• Incredible vulnerability to predation
• Failure to adapt to environmental changes
• Preference (nowadays) to estuarine habitat
• Colour, body shape, size, weight, courtship, displays, and vocal sounds
• Pre and Post-Copulatory behaviour (invariably there isn’t any!)
• Feeding patterns
• What they eat
• A small clutch size
• Egg shape, size and weight
• Colour, size and weight of progeny
• Specialised bill
• Flocking behaviour
• Preference for walking instead of flying
In fact having webbed feet is really the only feature brown teal have in common with other waterfowl.
Brown teal do not adapt readily to environmental changes, and it is believed that the long-term protection of remaining flock sites may well be a vital link in brown teal survival. Over the last 60, or so, years such flock sites have been mainly in estuarine areas and mostly at the confluence of fresh and seawater, but as already mentioned, this was not always the case and flocks of brown teal were found in every pond, lake, swamp, river and major wetland in New Zealand.
At a flock site progeny of the year will live quite happily together over a period of several months and it is not until the onset of the breeding season that aggravation amongst each other commences.
But, by far the most alarming feature of brown teal behaviour is the species vulnerability to predators – far more vulnerable than any other species of waterfowl.
However, in a protected environment – such as a captive one – they live very long lives; with 14, 15, 16, 17, 18, 22 & 24 years of age being recorded.
Just like all New Zealand endemic bird species, brown teal evolved in an almost totally predator free environment - for millions of years - and have never adapted to a modern environment full of predators.




SAVING BROWN TEAL
Between 1968 and 1987 the NZ Wildlife Service, which was replaced by the Department of Conservation in 1987, was active in protecting and enhancing brown teal habitats in Northland and on Great Barrier Island, and in 1976, the Wildlife Service, in association with Ducks Unlimited (NZ), established a major brown teal captive breeding programme, entitled “OPERATION PAKEKE” (‘Pateke’ being the Maori name for brown teal).
Between 1976 and 1999 c2,000 brown teal were reared in captivity, and c1,800 of these were released into the wild, at 29 different sites. During this highly successful captive breeding period a unique system of ‘natural pairing’ evolved – where each bird is allowed to choose its own partner. Once established a pair were retained in their own special aviary. This was so successful that in a single season participating breeders reared 153 brown teal.
Sadly, however, the intrinsic reasons for the decline of wild brown teal were not addressed and whilst captive released birds showed great adaptability to the wild, survived for long periods, and reared young, they too declined in the face of huge numbers of predators, just like their wild predecessors.
On top of this, the period 1990 to 1999 saw the recovery programme going rapidly backwards, largely through non-existent Dept of Conservation management, to eventually reach a point where the total wild population of brown teal had plummeted from c2,500 birds to c750 birds – c150 in Northland and c600 on Great Barrier Island - that by 2000 brown teal had become one of the world’s most endangered species of duck. Between 1990 and 1999 brown teal became a FORGOTTEN SPECIES amongst wildlife professionals.
In mid-1999 the disastrous state of the recovery programme became glaringly apparent when two individuals took it upon themselves to promote the plight of brown teal by appearing during prime viewing time on New Zealand’s National Television News, on a Sunday evening in September 1999, to clearly show that the recovery programme was really a very simple management exercise - all that was needed was to provide brown teal with a protected environment – but without a concerted effort brown teal would be totally extinct within the next fifteen years
By mid-1999 the plight of the captive brown teal population also became apparent, with the numbers in captivity having plummeted, over the previous decade, from c140 birds to c30 birds, and the numbers being reared annually dropping from c130 to c30.
The number of brown teal breeders, once spread from Northland to Southland, also became in danger of premature extinction when, over the same period, their numbers plummeted from 39 to just 9!
So, having irrevocable evidence of the dramatic decline of brown teal in the wild and in captivity, together with the abysmal track record of the recovery programme, those within the Department of Conservation’s ‘corridors of power’ were ‘persuaded’ to investigate the brown teal recovery programme and in late 1999 instigated a complete review/Audit of the whole programme. In October 2000 the Audit findings were duly published.


THE “AUDIT”
The Audit was compiled over a six-month period and close to forty people were interviewed. The published report was seen as a valuable and vitally important document, and an essential ‘guide’ towards saving brown teal.
From 2000 onwards the recovery programme has undoubtedly been turned around from one of imminent disaster to one of imminent success. Large-scale predator control programmes were introduced at a number of critically important sites in Northland and on Great Barrier Island. One of the most spectacular successes was the elimination of 50 stoats in one month at one site in Northland, and between 2001 and the end of 2004 the Northland population had risen dramatically from c200 brown teal to c400.

 

2500        *                                                                                 

2000                 *                                                                                     

1700                            *                                                                             *

1200                                      *                                                         *        

950                                                *                                     *

800                                                          *                 *

700                                                                    *

1988 1990 1992 1994 1996 1998 2000 2002 2004 2006 2007
BROWN TEAL POPULATION DYNAMICS OVER THE PAST 18 YEARS

The graph above shows the accelerating race towards extinction. Had the recovering programme not
been restructured in 2000 brown teal would have been totally extinct by c2015!
THE PRESENT RECOVERY PROGRAMME
Since the AUDIT in 2000 the brown teal recovery programme has made excellent progress and is now on a clearly defined plan that, over the next decade, will see brown teal numbers increase steadily in the wild. However, it is likely to take 20-30 years to reach a point where the future of brown teal is assured and to achieve this goal predator control programmes, habitat management and captive breeding must be ongoing indefinitely.
Also since 2000 the brown teal captive breeding programme has bounced back with a vengeance. C15 breeders are now actively participating and c100 birds are being reared each season. (In the words of the 2000 AUDIT “You can never have too many brown teal in captivity!”)
Since 2000 the input into predator control programmes, and the results being obtained, are impressive.
The results in the past 5 years confirm the Brown Teal Conservation Trust’s belief that given suitable and protected predator-free habitat brown teal will survive and breed very successfully.
The Trust also believes that on going research into brown teal habitat requirements, and into what brown teal eat in the wild, are vital ingredients to the long term survival of the species.
However, government priorities in New Zealand change with the wind and to help ensure the long-term viability of the recovery programme a major private sponsor may be needed.