What your apple core can do to our native birds

Department of Conservation —  11/02/2020

What may seem like a harmless action could be negatively impacting our native species.

You may be (unknowingly) contributing to our litter problem on public conservation land, simply because you’ve been told a sneaky lie.

This lie has passed down generations, without us taking much notice.

Parents tell their children that it’s okay, because “it’s biodegradable.”

And their parents said the same to them, for no other reason than we’ve just always believed it to be true.

Friends encourage friends to make the mistake – it “will help wildlife” or “be good for the soil.” It’s a lie not just told in New Zealand, but all around the world. It’s a lie that as tidy Kiwis, we shouldn’t stand for.

We’re talking about the lie of discarding organic waste, like apple cores, banana peels and any other food items in nature is harmless or even good for the environment.

For so long, you may have believed that throwing an apple core into nature was the right thing to do. Seems plausible, huh?

The harsh reality: food scraps can take years to break down in some areas and they feed predators like rats, stoats and mice.

Let’s bust the myths that make up the apple core lie.

Apple core in the Mangatepopo Valley, beside the Tongariro Alpine Crossing track | Photo: Julia Wells

Myth #1: Organic waste breaks down quickly in nature.

“Organic waste, or green waste, is organic material such as food, garden and lawn clippings. It can also include animal and plant based material and degradable carbon such as paper, cardboard and timber.”
Environment Victoria

Not all environments are created equal when it comes to waste breakdown. In general, an apple core takes about 2 months to break down in normal conditions. In alpine conditions, this can take years depending on the environmental conditions.

Even though these items break down quicker than plastic or glass, they still stay in nature for some time.

With this in mind: In popular sites, for example the Abel Tasman Coastal Track, if everyone leaves behind an apple core, that’s 300,000 apple cores left in nature.

This is why it’s so important to take your litter with you. Organic waste is waste; it harms our environment, our soil, our waterways and our wildlife.

Photo: Sabine Bernert

Myth #2: It’s a natural food source for wildlife.

When you feed our native wildlife, either directly or indirectly, you are disrupting their diets and changing their social behaviour.

In an episode of the Sounds of Science podcast, DOC vet Kate McInnes shares why your food scraps aren’t as appealing to wild birds as you may have been led to believe. Mainly because they lurk around, looking like they do, indeed, need the food.

Kate shares an example from the Kākā Cam – when fed just corn (which they love), the chicks will get a calcium-phosphorus imbalance.

“Their bones won’t grow properly. They’ll get bent beaks. They’ll get weak bones. And they’ll actually get broken bones.”

Even nuts can cause harm to the diet of a kākā. Kate compares nuts as “chippys and ice cream” to the kaka diet.

If kaka are eating nuts all day, they’re going to experience the obesity problems that comes with eating chips and ice cream all day.

Feeding can even change the natural behaviour of birds in the wild. They congregate in different ways and can contract disease a lot easier; this can cause stress in less dominant birds, and also more dominant birds who fight to gain access to the introduced food source.

Tongariro Crossing Track | Photo: Julia Wells

Myth #3: One apple core won’t hurt the environment.

It’s just an apple core, right? An apple core that can unnecessarily attract rats, mice, stoats and ferrets to precious areas on conservation land, where our most endangered native species live. By feeding introduced predators (yes, even that apple core you hid off the track), you are actively threatening the survival of New Zealand’s unique biodiversity.

What may seem harmless, can actually be halting our progress to a Predator Free New Zealand in 2050: the purpose is to preserve threatened species, improve our biodiversity, create greater ecological resilience and restore our unique ecosystems.

Chucking your apple core into nature, it’s in direct opposition to PF2050. Take it with you and help protect New Zealand’s native species.

Apple left in nature

Love This Place

This summer, we’re asking visitors to public conservation land to ‘Love This Place’ – a nationwide effort to engage domestic and international tourists to behave responsibly while travelling Aotearoa.

Many New Zealanders are unaware of the harm organic waste can do to our wildlife when left out in nature. Take your litter with you, even apple cores and banana peels.

What you can do when out in nature:

• Show you love this place by always being prepared to carry your litter away with you.

• There are no rubbish bins in the bush, so pack prepared

• Remove as much packaging as possible, so you don’t have to carry it out again

• Pack your food and supplies into reusable containers

• Take a bag or container to store your rubbish

• A leak-proof, air-tight container (e.g. an ice-cream container) is ideal

39 responses to What your apple core can do to our native birds


    Thank you! Very interesting insight on what I have often thought was ‘harmless’, it truly is important to practice leave no trace.


    Very informative and useful post! Surely learnt something new today. Please check out my recent post too on the need of practicing conservation by one and all in different ways and feel free to share your thoughts! 🙂 – https://thelifestyleleader.wordpress.com/2020/04/05/lifestyle-changes-for-the-bigger-cause/

    Sharon Bailey 20/02/2020 at 5:36 pm

    Why make such a fuss people? And why be so rude? Because you think you
    are anonymous? Come on – now that we’ve heard good reasons to not leave unnatural rubbish, let’s just take it with.Its not accusing anyone of devious behaviour – just ignorance. BTW the main thing I noticed the article mention was that our junk feeds rodents. (Your cyanide arguments were a side-track.)

    Gordy Wordy 19/02/2020 at 8:45 pm

    Is this mostly about the cyanide content of apple pips?


    This is mostly just speculation. If there was some actual evidence that apple cores and banana peels are significantly impacting native wildlife, \i would like to see it.

      Mrs ROse Pera 19/02/2020 at 9:30 pm

      This is very annoying to say that we have been telling lies about apple cores for years. if what you say is true, it has been a well intentioned belief, not a lie, you are making it sound like we, the older generation, is all about conning the world. Believe it or not, we are all just as keen on helping out nature as you who think you are the only ones who are trying to help the world survive. Grow up, DOC.


    Apple pips, like peach kernels and others, contain a small amount of cyanide.
    If that were to kill off some of the pests then I’d be all for discarding it in the bush.
    The problem is, we don’t want our birds to die the same way.
    There is not enough cyanide to to kill in one apple so it could be a slow death (if ONE bird finds enough apple cores. AT the same time, a rodent could possibly build up an immunity which could make things worse.
    I guess the best thing is, as suggested, take ALL rubbish home to the compost bin.


      This is a really uneducated chat about cyanide. You should give it a google.

      If you dont have enough cyanide to kill you it wont kill you. It’s why we dont die slowly after eating a few apple seeds.


    I am guilty of this here in America – I always think “carry in, carry out” doesn’t apply to organic food items… that habit changes now


    I think we have bigger problems than apple cores, eh?


      Like all the 1080 poison you’re dropping and killing the ecosystem which we are part of […] and you are worried about a few apple cores lol get a life for […] sake Doc. You’re doing a very bad job of protecting nature you’re killing it…

        Chris Sayer 18/02/2020 at 2:34 pm

        My thoughts exactly. Do you remove all the birds and dead animals after your 1080 drops.? I don’t think so.!


        What other option do they have? If all those people complaining about 1080 actually went out and helped cull the number of predators we have, maybe they wouldnt need to drop 1080…But no, everybody wants to complain but noone wants to help or offer other options. […]


    but if the animal die then free apple tree
    so […]

    Anne Donaldson 13/02/2020 at 9:49 am

    Thank you DOC – very informative. Will share with friends & family. Keep up the awesome work!


    What’s an Apple core compared to freedom campers […] every where maybe we should deal with that first it’s way worse!!!!


    And yous think throwing carrots laced with poison is right, […] ban 1080 you do more damage then the public.


    Native birds thrive in towns and gardens because of the exotic trees providing food for them. This may not be a ‘natural’ environment, but so? They need all the help they can get.

    Michael wynne 12/02/2020 at 6:45 pm

    Wondering about our bushfires in oz not to leave Apple cores or any food scraps when we are told of starving animals?

      Zachary Ting-Feng Ngow 12/02/2020 at 8:43 pm

      Did you know you can do more than one thing at a time?


      Feral cats kill an estimated 6 million individual indigenous critters in Australia per annum. The wild fires killed an estimated quarter of that this year. Tackling the feral cat issue would be very effective too.


    I wonder how many species will survive after our present extinction event has run its course. Its comments like this that perpetuate the illusion that all is well in our little corner of the world. Lol “ In the Age of Extinction, only love remains.”


    Where I live in the Whirinaki valley there are many wild apple trees from heritage strains. They are an asset to the valley. Their spring blossoms add beauty and nectar for bees etc.
    Their fruit is sought after by deer, pigs, possums, the free roaming horses and of course humans.
    Apple trees should be planted everywhere.


      So basically its a invasive species magnet.


      None of these are native though, and the pigs and possums are an active threat to native wildlife.

        Chris Sayer 18/02/2020 at 2:38 pm

        I’ve even heard of possums dragging babies out of tents and eating them.


      So the windfall apples are sought after by “pigs, possums…” and other undesirable mammals that humans have introduced to New Zealand? That sounds more like a reason to cut them down rather than plant them. Predator Free 2050


    I eat the core so there is no waste.


    I had no idea. I’ve always been an apple core chucker. I won’t be doing that anymore! Thanks DOC.


    people rarely see past their own nose… I never leave any seed pip fruit stone or other rubbish in our nature reserves.

    Shirley Newman 11/02/2020 at 8:21 pm

    Excellent info. 👍


    Very relevant article! I always wondered about this, and never felt comfortable about leaving food scraps in nature. Now I have more reasons to not do so. It’s also very common to see people throwing fruit peels/cores out through the window into the bush while driving on highways.


    I commend you on your well written article but do wonder why this has not been well publicized before.

      Dave Matthews 11/02/2020 at 9:23 pm

      This is not rocket science Trevor. Rubbish is rubbish and no food waste should ever be discarded in the back country. I was taught that 60 years ago.


      Like the 1080 poison they drop.
      Hypocrites 🙄