Week in Review
An audacious plan to save a rare species
With fewer kākā beak plants in the wild than kākāpō, conservationists have been testing novel ways to hold the fort on extinction.
It was an audacious plan to save a species involving a helicopter, a shotgun and shells full of seeds.
Only around 150 kākā beak (Clianthus Maximus) shrubs exist in the wild. With large bunches of crimson flowers, they’re a spring showstopper. Once-large patches would have brightened parts of the North Island. Unfortunately, as well as being beautiful, they’re delicious to introduced mammals.
Goats, deer, rabbits and hares have feasted on them to the point where there are fewer kākā beak than kākāpō.
The few plants which survive in the wild owe their life to making a precarious home on cliff faces clinging to spots where agile goats can’t even get to.
Hawke’s Bay's Forest Lifeforce Restoration Trust is attempting to increase the number of plants in the wild. Unless new plants are propagated in equally inaccessible places, their deliciousness spells doom.
That’s where the idea of the shotgun came in. Could seeds be shot into the sides of cliffs from a helicopter?
The trust’s forest manager Pete Shaw said there were a few different suggestions.
“People talked about paintball guns and sling shots and throwing balls out of helicopters over cliffs. I thought when you see them in the wild, they’ve got to be in quite specific sites where they are free of browsers, mainly goats. A shotgun seemed to be the ideal way of doing it.”
The idea was tested, seeds were shot into a tin of soil from a 20 metre distance which the team thought would be about the distance they could get by helicopter to cliffs. Eventually, they germinated. Trials in the wild, however, have not been so successful.
“One of the things you learn about kākā beak is they’re often an odd species to deal with. They don’t toe the line like you’d want them to.”
None of the seed shot into cliff faces have germinated so far.
Holding the fort on extinction
Fences, not shotguns, have been successful. The trust has planted around 350 kākā beak plants grown from wild-gathered seed in enclosures. With special fences designed to keep out animals they're doing well.
While 350 sounds like a big number when the total wild-growing population is 150, Shaw said the effort is really just holding the fort on extinction.
Without fences, or a sheer cliff face there's little hope the plant could survive on the mainland. The trust’s work is like an insurance plan until kākā beak can again find areas without goats, deer, rabbits and hare.
“In an ideal world you would have large areas where kākā beak can thrive, but in the meantime what we are trying to do is capture as many of those diverse natural genetics we can.”
There's no due-date on goat-free land and Predator Free 2050 won't be a kākā beak lifeline. Goats don't make it to the hit list.
Just how many goats are wandering around New Zealand’s forests? Shaw doesn’t know:
“Shivers. In Hawkes Bay there are thousands and thousands of them.”
The hunt for the kākā beak
With kākā beak easily available in garden centres, some may think botanist's toting seed-spreading shotguns is a bit extreme.
Having a plant in a front garden doesn’t contribute to the long-term viability of the species.
The garden centre plants are what Shaw describes as genetically flimsy. They’re the product of years of interbreeding from one or two wild plants.
To build a strong population as much genetic diversity as possible is needed. This increases the chances plants will survive a range of issues.
One of the trust’s goals is to find new plants to collect seeds from. Each new wild plant is a precious genetic gem. Shaw said the trust has found around 30 in the wild but hasn’t found any for the last five years. There may well be more, but in recent years he hasn't had the same time available to search for them.
He wants the public to keep a look-out in spring, when the bright red flowers make them easy to spot. The most likely areas they will be seen are Gisborne, East Cape, Hawkes Bay and around Lake Waikaremoana. If spotted, GPS coordinates should be noted and the local Department of Conservation office contacted.
“Any new plant is a big deal ... if you find a plant, normally you get your name attached to it because there are so few of them.”
Kākā beak DNA tinder
Once new plants are found, their offspring helps genetic diversity.
Since 2011 Manaaki Whena Landcare Research’s Dr Gary Houliston has been busy looking at DNA from each of the plants found in the wild. His knowledge makes him like tinder fairy godmother for kākā beak.
Like a dating service, his data lets conservationists know which plants to plant where.
“You do need some sort of gene flow, some genetic exchange.”
He describes it not as a breeding programme but an attempt at trying to keep populations healthy. When he first became involved in the project, he said conservationists were cautious about moving plants between sites.
“If you’re too cautious you can actually reinforce the inbreeding within the populations.”
When kākā beak were more widespread, inbreeding would have been less of an issue. Now isolated in cliff-face pockets, Houliston’s DNA work lets Shaw and his team know they can plant shrubs grown from seeds found in different sites together.
Shaw still holds some hope the seeds shot into cliff faces will germinate and more plants will thrive free of pest fences.
Kākā beak seeds can stay in the ground like little red time capsules for many years before germinating.
He said some kākā beak were found in a former kanuka forest which had been crushed with a roller, set on fire, and then had plantation pine planted on it for 25 to 30 years.
“They had been through all of that disturbance and those seeds were still viable in the ground.”