The disappearance of frogs and butterflies indicates the environment is “out of whack”, according to Kaimaumau orchardist Grace Wright.
When she and husband Bill Wright moved to Kaimaumau, 30km north of Kaitaia, 17 years ago, the swampy 4ha site of their present orchard was home to untold frogs.
Even after Bill got busy on drainage work using gear he had kept from their former excavating business back in Taranaki, the croaking crescendo was “deafening” after dark.
The couple planted avocados, and about 10 years ago HortResearch gave them some blueberry plants for a trial to see if the species – usually grown in colder climates – would survive in the subtropical Far North.
“The idea was to see if we could produce blueberries for the United States’ Thanksgiving Day market,” Grace said.
Thanksgiving is celebrated on the fourth Thursday in November and the Kaimaumau crop “worked perfectly” to fit into that time slot.
HortResearch – its project completed – gifted the blueberries to the Wrights, who let the weeds grow among the three rows of plants for a couple of years.
” Then we got a bumper crop,” Grace said.
Their interest revived, they built a canopy of bird netting covering a hectare, expanded their rows of blueberries and today harvest about 1.5 tonnes of the berries annually, selling them at farmers’ markets in Kerikeri and Whangarei.
About four years ago Grace decided to try breeding butterflies in the balmy conditions under the bird netting. She put in several varieties of milkweed favoured by monarch butterfly caterpillars and waited to see what would happen as caterpillars breeding locally converged on the feast laid out for them.
“The first year we tagged and released 500 monarchs,” she said.
“You swat it with a butterfly net then stick a very light adhesive number on to its wings. Someone who finds it later on reports the number to the Butterfly Trust and it helps record the monarch’s migration pattern.”
In 2008, there were 200 monarchs tagged and released. Last year there were four and this year there have been none.
And now the nights are silent. The frogs have gone too.
“I don’t know what’s happening,” Grace said. “But I’ve heard the first two things to disappear when the environment is out of whack are frogs and butterflies.”
The Wrights use Roundup for weed control between their rows of blueberries. All their fertilisers are organic and they don’t spray their avocados, happy they can sell their “mediocre” harvest as spray-free fruit at farmers’ markets.
Grace won’t comment on what could be causing the environmental upset which has driven out fragile frogs and butterflies. She gets on well with her neighbours, and wants the good relations to continue.
Butterfly Trust secretary Jacqui Knight, formerly of Russell and now living in Auckland, is not under the same constraints.
She blames pesticides used to combat clover root weevil and other pasture pests, and the sprays used to protect the big new plantings of avocados which can be seen by State Highway 1 from before Waiharara to Pukenui and further north.
“We will never know for sure how much damage these chemicals are doing to our environment,” Ms Knight said.
“In 1891 Coca-Cola was said to be an ‘ideal brain tonic’ and less than 100 years ago cigarettes were being touted as good for our health.”