With widespread yellow-eyed penguin chick deaths in Otago this year and colonies in some areas producing no chicks, a Moeraki penguin rescuer is questioning why the Department of Conservation does not intervene more to help save the endangered species.
Administering drugs to penguin chicks during the breeding season could be a key for the species' survival, Penguin Rescue manager Rosalie Goldsworthy said.
She said the charitable organisation ran a volunteer-led intervention programme, giving antibiotics to penguin chicks at the colony it manages, which saved the lives of scores of chicks of the endemic endangered species. And she questioned why the management technique was not being used by the Department of Conservation (Doc).
After a third straight season of the little-understood disease avian diphtheria running through the colony at Moeraki, Mrs Goldsworthy said she remained convinced a course of antibiotics in the first three to four weeks of a yellow-eyed penguin's life could make all the difference for colonies.
''You need to have a survival rate better than one chick per nest for the colony to continue,'' she said.
''It's inevitable - if they're not replacing themselves, they're down the tubes.
''They [Doc] already know what we do - and that it works.''
At Moeraki, of 42 nests, six failed and the remaining 36 nests produced 57 chicks.
Forty-seven of the chicks were treated with antibiotics and survived as a result, she said.
Widespread yellow-eyed penguin chick deaths in Otago this year come on top of yet another decline in the number of nests established on the coast of mainland New Zealand.
Estimates of 250 yellow-eyed penguin nests was down on the previous year's 261, which had already lowered the bar as the fewest nests in a quarter of a century.
Last month the University of Otago's Dr Thomas Mattern told the Otago Daily Times the biggest issue, among various reasons, for the ongoing population decline of what Doc calls possibly ''one of the world's rarest penguin species'' was ''penguins living far too close to humans''.
The human activity he targeted was the fishing industry and, along with Forest & Bird, he called for the fishing industry to alter its practices concerning set netting.
Mrs Goldsworthy said the battle to save the birds would have to be fought on many fronts, but she could continue to administer antibiotics to penguin chicks.
Getting to chicks early and administering antibiotics for a period of five days would have a positive impact on population numbers and the species' chance of survival.
''At about three weeks two things happen, it [a penguin chick] stands up, and its own immune system kicks in,'' she said.
''At places like Bushy Beach [in Oamaru] where all the chicks died, that colony is doomed, and it is not acceptable, is it?''
Doc veterinarian Kate McInnes said the department was ''aware and is working on issues with avian diphtheria - particularly around the Otago coastline, where it is most prevalent in yellow-eyed penguin (hoiho) chicks''.
''Some sites have lost many or all their chicks to avian diphtheria. But others have not.''
She said three summers ago Doc monitored the outcome of different treatment options for the disease but did not look at antibiotic use due to the high level of intervention/disturbance it required.
Instead, the removal of the lesions the disease caused in chicks' mouths was found to be effective - and required one visit as opposed to the five antibiotics treatments would require.
Doc still considered antibiotics treatments an option ''if warranted'', but given the intervention involved, would not choose it lightly.
The reasons behind nest failure were complex and varied between sites, she said, and applying one management method without taking account of local conditions was, in addition to being wasteful of resources, a potential source of pathogens.
Further, Doc Coastal Otago operations manager Annie Wallace said due to the dispersal of penguin nests along the Otago and Southland coastline regular access was difficult and in some cases made intervention not viable.
The birds faced ''a range of threats, posing some critical management challenges for all those working on their recovery''.
''We recognise the seriousness of the situation for hoiho with numbers of this taonga species continuing to decline at key nesting sites despite robust predator control and other land-based interventions,'' she wrote in an email.
''We are urgently working with MPI [the Ministry for Primary Industries], Ngai Tahu, the Yellow-eyed Penguin Trust, other site managers and others involved in their recovery to better understand the factors contributing to their decline.''
Conservation Minister Eugenie Sage said she was ''seriously concerned'' by the ongoing decline of yellow-eyed penguin numbers.
She noted Doc's work on a recovery plan for the species with Ngai Tahu and the Yellow-eyed Penguin Trust, as well as her request that Doc investigate ''potential impacts'' on the birds from being caught in fishing nets ''and how to best deal with this''.
Doc confirmed it had compiled a list of nest checks from a variety of sources but declined to share it with the ODT as it ''might be a little bit sensitive or incomplete or in process''.
