Steve Henderson, a Pest Management Officer with the Northland Regional Council, says spring is heaven for hungry possums after the lean times of winter.
“People who have willow, poplar and similar types of trees may notice worn tracks in the grass leading to them as the possums make their nightly trips to forage on the new growth.”
Mr Henderson says branches broken by possums as they try to reach succulent new growth are another telltale sign.
“Oak trees are also a favourite this time of the year and if you have one of these trees you can bet every possum in the neighbourhood also knows about it and will be making a beeline for it every night.”
Roses are another possum delicacy and many gardeners have suffered the annoyance of having their rose garden invaded and destroyed overnight.
However, he says native trees are not immune to the possum’s unwelcome attentions either.
“Puriri, totara and pohutukawa in particular can all take a hammering as their new growth sprouts away. Pastoral farmers trying to get a new grass established may also notice bare patches, particularly where the land is close to blocks of bush.”
Mr Henderson says landowners keen to protect their property from marauding possums have a number of options.
“Rural landowners and others living away from built up areas will find night shooting in poplars as and willows very productive, especially before the foliage can get too thick and offer possums somewhere to hide. Dogs can also be helpful in ensuring possums remain in the trees and can’t climb down to escape.”
Mr Henderson says poisoning with fast-acting poisons such as cyanide and phosphorus is another option, but these require a licence to use.
“People without a licence to use these restricted poisons can either hire a pest control contractor to lay poisons on their behalf or use a non-restricted toxin such as ‘Pestoff’. But it can take two to three weeks for a possum to succumb to the effects of slower-acting poisons like Pestoff, during which time the animal can still be causing havoc so getting in early is a priority.”
Mr Henderson says there are a number of different sorts of traps that can be used very successfully, although these can be labour intensive over a big area.
“Remember too, that if leg hold traps are being used, care is needed to prevent accidentally catching ground-dwelling birds and other non-target species.”
Mr Henderson says Timms traps and live capture traps also work very well, provided sufficient are used. Legally, all live capture traps must be checked daily.
“A good strategy to maximise the use of a few traps over a wider area with lower possum numbers is to pre-feed prior to trapping. This involves leaving bait and noting where it gets taken from. Traps can then be placed in those areas.”
He says possums can be “a little picky” in spring when there’s so much other food about. However, apples and carrots spiced with cinnamon, flour and icing sugar can make a big difference to a trap’s attractiveness.
Apply a mixture of plain flour and about 20 percent icing sugar with a little cinnamon powder to halves or quarters of apples or carrots.
“Signs that you have been successful on a spring campaign will be densely foliated trees without broken branches. Native totara, pohutukawa and puriri will develop nicely rounded shapes on their canopies and be able to support native birds through the nesting season. Around the garden, roses will flourish and fruit trees will be able to develop fruit to full potential.”
Mr Henderson says Northland Regional Council pest management staff can help with year-round advice on possum control, competitively priced traps, poisons and ammunition.