What is “Mega Mast?”
Mega Mast or exceptionally heavy seeding, occurs in New Zealand forests when trees produce an unusually large amount of flowers and seed. Scientists believe this is caused when an average summer temperature was more than a degree higher than the average temperature of the preceding summer. Last summer was two degrees warmer than the summer.
How can a Mast be predicted?
Extensive seed sampling is carried out across the country during February and March. Sampling indicated the biggest beech mast across 90% of NZ’s beech forests for more than 40 years, with particularly high heavy seed loads in South Island forests. Rimu forests and tussock grasslands also indicated heavy seeding. Not only are beech and rimu trees heavily ladened, but Forest & Bird are concerned that kahikatea, totara, matai and miro were also masting at the same time across most of the country.
Why is Mega Mast a problem?
Whilst increased forest seeding provides a food bonanza for our native species, it also provides an almost unlimited supply of food for rodents and stoats causing the predator population to explode. Birds like the kakariki, mohua, kiwi, kaka, kokako, kea, whio and tuke are all vulnerable to rat plagues, but birds are not the only native species at risk. Our endangered New Zealand bats, native frogs, lizards and also the unique giant land snail are all vulnerable to an increased rat and stoat population. “It’s a double whammy” says Kevin Hackwell from Forest & Bird, “This is going to put a huge amount of pressure on our forest and our wildlife – no question”.
During the 2001 Mast, populations of endangered species were wiped out including the only known population of mohua (yellowbird) north of Canterbury in the Marlborough Sounds.
What is New Zealand’s response?
The Minister of Conservation the Honourable Eugenie Sage said “DOC is planning its largest ever predator control programme for 2019/2020. Responding to the increased threat from introduced predators during such a big Mast year is critical if we are to retain our unique native species that sets New Zealand apart from the rest of the world. We won’t be able to treat, this year, all the forests that are Masting,” Elliott says, “so there’s a prioritisation exercise. We’re still planning and budgeting.”
Not all bad news
Although many native birds will be threatened by the Mega Mast, it is expected to be a boon for one of the country’s beloved parrots, the kakapo. Areas that are home to the two main populations of Kakapo (Whenua Hou north west of Stewart Island and Puke Nui in the Dusky Sound) have really high amounts of fruit on the rimu tree. Andrew Digby who is a Kakapo and Takahe expert at DOC said “It’s the biggest rimu Mast we have ever recorded. We are expecting the biggest kakapo breeding season that we have on record in recent years. It means that pretty much every female kakapo of breeding age will breed on those islands which will be a much needed boost. It’s going to be a big one for us”.
How will it affect me?
Huge rodent numbers will not only be limited to the bush but urban and rural areas will also see higher numbers of rodents in and around properties.
Prepare yourself for the invasion! – at NiceBuys we sell a large range of cages, traps, rodent repellers and bait stations to capture these pesky predators and keep your home rodent free. For our full range see the NiceBuys website