Blue penguins becoming island refugees

Forest and Bird, Volume 23, Issue 1, 1 February 1992, Page 16

Blue penguins becoming island refugees

Alan Tennyson

In Australia more tourists visit Victoria’ Phillip Island blue penguin colony than the Great Barrier Reef, yet New Zealanders pay little attention to these endearing penguins, which nest close to most of our main cities Many mainland New Zealand colonies are being wiped out by continuing threats from predation, set nets, cars, human persecution and habitat

destruction.

describes how we need to act quickly if we

want to save the dwindling mainland colonies.

N THE EYES of children, nothing can beat the cute, waddling, somewhat comical appearance of a penguin. But just thinking that penguins are cute has done nothing to stop the decline of the one penguin species that is accessible to all New Zealanders. Unlike the penguins commonly thought of, it is not confined to the Antarctic or some remote subantarctic island. The blue penguin occurs in more northerly latitudes and agreeable climates and it is the only species that breeds widely throughout New Zealand.

Unfortunately, it is this liking of warmer waters that has led to its demise, because wherever it has come in contact with humans it has suffered. Australians Colin Stahel and Rosemary Gales wrote in their 1987 book on blue penguins: "There are very few, if any, cases where the close proximity of human habitation has not resulted in either a decline in [blue] penguin breeding numbers or their complete disappearance from the areaz> While their yellow-eyed cousins have become media mega-stars (and deservedly so), most people seem to be unaware of

the plight of the blue penguin. Residents of Otago, Southland and south Westland have the benefit of being able to easily reach yellow-eyed or Fiordland crested Penguin colonies, but the majority of New Zealanders live hundreds of kilometres away from these areas. While these rarer species need all the help they can get, it is the blue penguin that most people have the chance to help first-hand, and there is a great deal to be done. In some cases, conservation can literally start at home — those fortunate enough to have blue penguins nesting under their floorboards can make sure their pet dogs and cats are kept away from the birds. HE BLUE PENGUIN or korora is a species confined to New Zealand and southern Australia. It is the smallest of the world’s 17 penguins, standing at about 30 cm and weighing in at about 1 kg. Current thinking recognises only one species of blue penguin, but distinctive white-flippered birds nest around Banks Peninsula and north Canterbury’s Motunau Island. Colonies range in size from a few scattered nests to many thousands of birds. Nests are normally among rocks or in burrows under vegetation, where two eggs are laid each spring. Surprisingly, blue penguins think nothing of walking long distances to their nests, which have been found at an altitude of nearly 300 m and 1.5 km from the sea. Both sexes incubate the eggs which hatch after about 36 days. The chick takes a further eight weeks to rear. In normal years, roughly one third of nesting pairs will rear two chicks, one third will raise one chick, and one third will raise no chicks. Occasionally two broods of chicks can be reared in a single season. After leaving the nest, chicks are independent of their parents and disperse from their natal colony. Some travel up to 1,000 km from their nest during their initial dispersal. Most will return to their natal colony to breed when three years old, but about 50 percent will die before reaching adulthood. The record for blue penguin longevity is 21 years. Unlike other seabirds, penguins are forced to fast on land during their annual moult because they need a complete covering of waterproof feathers to survive at sea. Large fat reserves are built up before the moult, with birds sometimes reaching twice their normal weight. Replacing the entire feather coat takes only 2-3 weeks. Since penguins do not fly, their foraging range is much less than other seabirds. While some petrels may be able to clock up speeds of 100 km an hour, blue pen-

guins can only achieve a maximum swimming speed of about 6 km an hour. As a consequence, blue penguins are coastal birds — usually feeding within 10 km of the shore. The species normally dives to 5 to 20 metres, spending up to a minute underwater per dive. At the extreme, it can reach depths of 70 metres. Their diet consists mainly of squid, small fish and crustaceans and feeding is usually carried out in daylight. R.B. OLIVER stated in his comprehensive book on New Zealand’s birds, published in 1930, that blue penguins were "found commonly along the coast from North Cape to Foveaux Strait and on outlying islands". Only on the Canterbury coast was the species described as "not common", but there it was replaced by the white-flippered form which bred

"plentifully all around the [Banks Peninsula] coast." By comparison, the Ornithological Society’s ten year nationwide bird mapping scheme during 1969-79 revealed a fragmented distribution around the coast. While the survey was not comprehensive, it gives us a good idea where blue penguins have declined. Few records came from the North Island south of Auckland. In the South Island, apart from many records in Malborough/Nelson, Banks and Otago peninsulas and Fiordland, only scattered records were received from the

west, east and southern coasts. Many sightings came from Stewart and smaller offshore islands. In 1955 when Oliver produced his second edition of New Zealand Birds he added that "this penguin has suffered a reduction in its numbers through clearing of scrub and forest from its nesting sites; being killed by dogs, cats, stoats and ferrets; being covered by oil discharged from ships; and lastly, where it crosses a coastal road to breed, being run over by motor cars." Despite this knowledge, little has been done to stop the species declining. Valuable long-term studies are underway on Somes Island in Wellington Harbour and at the large Motunau Island colony of about 5,000 birds, but we have very little knowledge of most surviving mainland colonies which are more than likely in decline.

HERE ARE a number of causes of unnatural penguin death. The sight of dogs chasing a flock of gulls or oystercatchers from their roost is a common event on New Zealand’s beaches. Fortunately most birds can fly to escape dogs’ predatory instincts. Flightless and ground-dwelling species such as kiwis and penguins are not so fortunate and have suffered terribly from uncontrolled dog attacks. Two recent incidents of dog predation on blue penguins epitomise the problem. At one part of the Oamaru colony,

* Blue penguins °

dog predation has been recorded for several years, including 15 deaths in December 1990, eight killed in one night in July 1991 and a further five in late September. This part of the colony was thought to number about 70 in 1990 but must now be heading for rapid extinction. At Piha Beach on Auckland’s west coast, residents tried for years to get the local council to control dogs in the area. The dog predation problem increased in the late 1980s with 30 penguin deaths recorded in two years and the colony was reportedly wiped out by 1990. Introduced cats, ferrets and, in Australia, foxes and dingos, are also known to kill large numbers of blue penguins at their colonies. Cats killed about 20 blue penguins in only three days in one instance at Wedge Island, Tasmania. Ferrets have killed up to 90 percent of chicks and 5 percent of adults on Banks Peninsula colonies in a season. As a result, some colonies on the peninsula have disap-

peared in recent years and others are much depleted. Penguins are frequent victims of set nets. The numbers of penguins drowned will remain a mystery while set netting goes largely unmonitored. It is certain that many more blue penguins drown in set nets than are reported. Nevertheless, Forest and Bird has compiled records of blue penguin drownings in the Bay of Plenty, Taranaki, Wellington, Nelson, Malborough, Kaikoura, Canterbury and Otago. The worst reported incident involving this species is of 16 whiteflippered penguins caught off Motunau Island in December 1985. They also drown in gill nets off Australia. Blue penguins have also drowned in box-nets — a fishing method used briefly in New Zealand before it proved uneconomic. The decrease in food supplies is another problem. In some years huge numbers of blue penguins, particularly fledglings, will die and beaches can be

littered with corpses. The Ornithological Society’s "beach patrol" scheme normally records 300-1,000 dead blue penguins washed up on New Zealand’s coast each year. Nearly 5,400 were found in 1985, and 3,729 were recorded from northeastern North Island coasts in 1974. Such mortalities are thought to be "natural" events caused by a collapse in numbers of prey species. Human over-fishing of penguin prey species, such as pilchards and anchovies, 1s likely to increase the number of such mass die-offs. New Zealand fish stocks are only managed on a species by species basis, rather than an ecosystem basis, which means the penguin’s entire food supply could be removed without any consideration of its effect on the penguin. For blue penguins nesting near human habitation, cars can be a big problem. A human preference for waterfront roads and sub-divisions has often led to a deadly strip of asphalt being built between penguins’ traditional nest sites and the sea. In

some waterfront areas, such as Wellington Harbour, trains regularly kill penguins. Penguins probably spend more time on the surface of the sea than any other type of bird and this makes them particularly vulnerable to entanglement in plastic rubbish and oil slicks. Many blue penguins have been found with beer six-pack rings around their heads or entangled in discarded nylon fishing line. Large oil spills adjacent to penguin colonies can be disastrous. In 1990, more than 200 blue penguins were oiled off Victoria, Australia, in one slick. However, overall, small scale oil spills may cause just as many blue penguin deaths. Out of 42 freshly dead blue penguins washed up on the New Zealand coast that I have examined in the last ten years, two (almost five percent) have been oiled. From 56 chicks banded by Fred Kinsky on Somes Island, only two were recovered within a year: one dead on a beach and one live but oilstained and exhausted. Similar problems occur in Australia — for example, an average of one or two oiled blue penguins are reported in Victoria each year. The incidence of oiled and entangled penguins clearly needs more study, but reported instances are frequent enough to cause concern. Deliberate acts of violence against such vulnerable birds also occur. In some areas,

blue penguins have been used as bait in rock Jobster pots. A spate of shootings occurred at Evans Bay, Wellington Harbour in 1981 — about 20 penguins were found shot or mauled by dogs. Shootings still occur here, one in June 1984, and the latest in August 1991. Some people take exception to the rather noisy, guttural brayings that emanate from penguins’ nests near their houses, but it must be remembered that the penguins were here long before people invaded and destroyed their colonies. HERE ARE big bucks to be made from the little blues. Most New Zealanders live within an hour’s drive of places where blue penguins come ashore under the cover of darkness to their nests. Blue penguins are present at colonies during most of the year. While New Zealand’s mainland blue penguin populations are being or have been wiped out, Australia is investing heavily in blue penguin conservation. With nearly 500,000 tourists visiting Victoria’s Phillip Island "penguin parade" each year, officials have seen the sense of putting money into penguin protection. Blue penguin watching on Phillip Island adds $60 million per year to the Victorian

economy. It is said to be Australia’s second most popular natural tourist attraction after Uluru (Ayers Rock). All revenue generated is re-invested in the penguin reserve for the benefit of the penguins. Phillip Island isn’t the only blue penguin colony in Australia that has organised tourist visits. There are two mainland sites in Victoria, two island colonies off South Australia and one off New South Wales. Tasmania has one island and one mainland colony where penguin tours are taken. In Western Australia a venture has Just started up, with cruises to a colony of 300 pairs on Penguin Island, off Rockingham. Mainland New Zealand colonies couldn’t match Phillip Island for its sheer number of penguins where some 24,000 are present, but to most, the sight of five penguins can be nearly as exciting as seeing 500. The many Australian tourist ventures, some to colonies with less than 100 birds, demonstrate that small colonies can be used successfully for tourism. Yet in most parts of New Zealand, coastal blue penguin colonies are just ignored, despite the growing popularity of Otago’s yellow-eyed penguin tourist ventures. One exception is the nature-based tourism venture of Akaroa Harbour Cruises who take people out on the scenic harbour to view Hector’s dolphins, fur seals and blue penguins. In Oamaru authorities are deciding whether or not to form a fenced reserve to protect the 400-strong local blue penguin colony, particularly from dogs. The colony there could become a great tourist drawcard for a region struggling for employment opportunities. Residents, such as Lorraine Adams, and local Department of Conservation staff are working to persuade the Waitaki District Council to form the reserve. The council’s Mayor, Mr Reg Denny, considers part of the area occupied by the penguin colony may need to be developed for cement works. Unfortunately in this era of budget cut-backs, promoting the financial benefits from penguin tourism may be the only way that money is put aside for penguin protection. ORTUNATELY, the plight of some mainland blue penguin colonies is being taken seriously by locals, but as yet there is no national coordination to systematically protect the colonies. On Wellington’s southern coast, concern over road kills has led to road signs being put up and nest boxes being installed on the seaward side of the road. Wellington Central Rotary Club with

Blue penguins *

sponsorship from Trustbank, in conjunction with DoC’s Wellington Conservancy and Conservation Corps, has coordinated work on the nest boxes. Students such as those at Mount Cook school helped to build the boxes. The recently installed boxes have already been occupied by a few penguins and it is expected that their use will increase. In addition, the Ministry of Agriculture and Fisheries in Wellington has tried to "‘penguin proof" the storm water drains of their Evans Bay building to stop birds from entering the drains and becoming trapped. DoC’s West Coast Conservancy has recently undertaken surveys in north Westland to determine where to erect road signs warning motorists to look out for penguins which are frequently run over in the Paparoa region. The survey will also assist staff carrying out predator control. Unfortunately the survey results suggest that the local population is declining. Many empty burrows were found. The most detailed New Zealand work is being carried out by Chris Challies on Canterbury colonies at Banks Peninsula and Motunau Island. His study has been ongoing for more than 20 years. At Godley Head, at the entrance to Lyttelton Harbour, ferret predation has been a big

problem in recent years with much of the colony being eliminated. Fortunately trapping now controls these pests. He has received Forest and Bird Canterbury branch’s Stocker Scholarship to help him continue predator control and penguin monitoring work. Having already managed to get most of the breeders at Godley Head to start nesting in artificial boxes, he is attempting to re-populate the depleted colony by moving well-grown chicks from other colonies into boxes there. The idea being that a young penguin will return to breed wherever it spent its last days ashore as a chick, and wherever it first ventured into the sea. This technique has proven remarkably successful with many transferred chicks returning to Godley Head to breed. Farmers and DoC staff are also working to control predators, especially ferrets, at Banks Peninsula colonies, and ferretproof fencing is being considered around one colony (see Forest & Bird, November 1991). At Oamaru, DoC and locals have tried ta, restore blue penguin habitat by improving the area for natural nest sites, constructing nest boxes and planting native coastal plants. The district council is funding a study on the penguins this summer.

AN BLUE PENGUINS survive on the mainland? Without intervention the answer is almost certainly "No". Visiting Victorian penguin expert Peter Dann (who is in the country on an ANZAC fellowship to study and survey the blue penguin in Otago), predicted a bleak future for New Zealand’s mainland populations: "In Australia, dingos, foxes. and dogs have largely restricted the population to offshore islands and inaccessible mainland sites. New Zealand populations face similar problems, particularly from dogs and ferrets." There is no immediate danger of blue penguins becoming extinct because large island colonies can safeguard the long term survival of the species, but like kaka and kakariki, if we want to retain mainland populations active management will be required. This should include: * a nationally coordinated detailed survey, and follow-up monitoring, of all mainland colonies * identification of areas where active management, such as predator control or chick transfers, is required and is feasible * education programmes in areas where home owners and recreational users could cause problems for penguins ¢ establishment of dog-free zones around colonies * formal protection of all penguin colonies and colony habitat restoration. If blue penguins are going to be protected at sea we will need to reduce marine pollution, consider other species in the food chain when setting commercial fishing quotas, and outlaw the indiscriminate, wasteful fishing method of set netting which is a threat to all coastal seabirds and marine mammals. Blue penguins are a source of delight to all who see them, yet we take them for granted. Unless action is taken now to halt the decline of mainland colonies, the sight of penguins in inshore waters will become a rarity away from island colonies. We will forget that penguins once nested alongside people under coastal baches, and those "penguin crossing" road signs will just become redundant relics of the past. Acknowledgements Thanks to Peter Dann, David Bishop and Chris Challies for their help and to Suzie Brow for ferreting out some old news articles. # Alan Tennyson is a researcher at Forest and Bird head office in Wellington.