This is a great time of year to appreciate some of the significant links between plants and the animals that rely on them for food.
As you walk through Shakespear Regional Park, take a closer look at the trees to see which ones are currently fruiting. The low-growing karo or turpentine trees are now laden with ripening fruit, which open to reveal sticky black seeds. I’ve seen tūī and bellbird (korimako), whitehead (pōpokatea) and saddleback (tīeke) all feeding on these seeds.
This has been a big year for kohekohe fruit. The female trees are laden with large fruit that look at first glance like green grapes growing out of the main trunk and branches. They ripen to a brownish colour and then open to reveal bright red fleshy fruit. On Tiritiri Matangi Island the kōkako seem particularly keen on kohekohe, while in the park they are a favourite of tūī and kererū.
It’s more difficult to spot the tiny flowers and fruit on wire vine (pohuehue), but you can tell they are there when the red-crowned parakeets (kākāriki) and kererū descend to feed on them.
While some of our trees are currently fruiting and providing a generous supply of nutritious food, it’s important to remember that the resident birds, reptiles and invertebrates mostly rely on the bush to provide food every day of the year. So, while people are encouraged to eat what’s currently in season, the birds have no choice but to do so.
Scientists sometimes categorise birds by the types of food they eat, so there are groups that feed on nectar, seeds, and invertebrates. But most of our birds don’t rely on just one food source and would be better labelled as omnivores – eating lots of different food types. Just as I mentioned kōkako eating kohekohe fruit, they’ve also been feasting on cicadas over the past few weeks. And, when the flax is flowering, many of our bird species get a dusting of orange flax pollen on their foreheads as they reach into the flowers for nectar.
This dependence on a wide range of plant food presents a challenge for conservationists who are trying to restore the bush so that it will support our native animals. The first steps in replanting bush tend to use what’s called ‘pioneer species’. These are the tough, drought tolerant, reliably growing species including mānuka, kānuka, flax (harakeke), karo, māpou, māhoe, coprosma species and ngaio. The idea is that these grow rapidly and soon form a closed canopy. Once the canopy is closed, it is possible to inter-plant with succession species that will eventually be the huge dominant trees in the bush. It is important to select and plant a wide range of species to ensure that when bush is established, it will eventually provide the year-round supply of food vital for birds and other creatures.