The interior design tastes of Mullet the little blue penguin are causing concern for those who provide guardianship and protection during the crucial penguin nesting and chick season and beyond.
Mullet, in his futile search for leaf litter to line his Moturiki burrow, has instead adapted diving petrel feathers. The main problem is that the feathers are attached to one of the decomposing petrel carcasses discarded by a marauding domestic cat.
This disturbing development in the ongoing fight for survival of our vulnerable petrel and penguin colonies has alarmed Western Bay Wildlife’s trust chairperson Melissa McLuskie, who leads the little blue penguin research, and Julia Graham - well-known locally as Mount Maunganui’s ‘Penguin Lady’.
“A cat is killing the diving petrels and stashing their bodies under a rock,” explains Julia. “That’s not unusual in itself, but on the trail cam footage we’ve noticed that Mullet has been going and getting the carcasses of these dead birds, dragging them down to his burrow and lining his nest with them.”
A contributing factor to the issue is that people are not staying to the trails when walking on Moturiki and Mauao.
“There’s not a lot of leaf litter or undergrowth on Moturiki. When people go off the beaten tracks, they’re pushing the leaf litter down to the bottom and it gets washed out into the ocean. If penguins don’t have leaves and twigs for their nests the next best thing is obviously feathers. They just happen to be attached to a dead bird.”
A colony of around 45 diving petrels was wiped out on Moturiki in 2014 by Humphrey, another local domestic cat that had gone hunting at night. At the time, Julia’s team captured images of Humphrey on a trail camera and were able to track down his home and owners. They quickly returned Humphrey to his previous home on a farm.
“Humphrey had been fixed,” says Julia, “but once a cat finds a good area they realise they actually don’t have to work very hard for it. These birds are sitting there. The cats don’t have to chase them. There’s no effort involved. It’s like going through a KFC drive-thru.”
It’s taken nearly seven years for that diving petrel colony to begin re-establishing itself on Moturiki after the huge loss of over 700 birds during the Rena oil spill and Humphrey’s deadly foray, only for them to be faced once again with the same fight for survival.
“If it keeps up we’re going to risk losing all the petrel population.”
Meanwhile Mullet is doing his best to rear his family after abandoning his nest in 2020. Last year Melissa discovered Mullet’s nest on a stash of wild rock pigeon and petrel carcasses; it had been trampled and eggs crushed due to people going off-track.
“So that was two less penguins on Moturiki that could have contributed to the declining population,” says Melissa.
“The impact of humans on the native birds’ habitat is huge and this is an extremely vulnerable area with threatened native species. The petrels are on the ground – they can’t flap their wings and fly away like other species, and penguins can’t fly at all.
“People don’t realise that when they run up and down the tracks and don’t follow the stairs but climb the banks, that they’re not only damaging seedlings and causing erosion but also taking away that layer of leaf debris which helps preserve moisture and provide insect cover.”
“Penguins are crazy little buggers,” says Julia. “We initially thought the cat or a weasel was hiding the carcasses in burrows and the penguins were coming along and nesting on top of the bird bodies. Thanks to the hard work of volunteers helping with research, we know for sure Mullet is getting the carcasses himself.
“The penguins are at risk from diseases that other birds can carry, particularly rock pigeons as they are an introduced species and carry a multitude of diseases. They also pose a risk to human health. Mullet might not necessarily go too close to a diving petrel or pigeon, but having decomposing carcasses in his burrow is not great.”
The substantially growing rock pigeon population is attracting cats, rats and weasels and are a great food source for them. Once predators are on the island, they discover the vulnerable ground-nesting birds.
Melissa says it is heartbreaking to watch growing, healthy penguin chicks getting ready to make their way out to sea suddenly disappear from a nest.
“This has been going on for the past few years. Owners are failing to keep these cats indoors at night and our wildlife are suffering, nationwide.”
Julia says putting a bell on a cat “just doesn’t cut it”.
“Petrels are attracted to noises, so a bell on a cat is more likely to attract the petrel to the cat than anything else.”
To assist Western Bay Wildlife with their ongoing work, visit: www.westernbaywildlife.nz