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Ongaonga

Tree Nettle

Urtica ferox

Their Story

Ongaonga (tree nettle) is one of Aotearoa’s most fearsome native shrubs — endemic, venomous, and beautiful. Found along forest margins and streams, its presence in the Brook Waimārama Sanctuary is a blessing and a pain. The plant is best admired at a safe distance.

This woody shrub can reach up to 3 m tall and has a broad, spreading growth. Leaves are pale green with large, coarse teeth, and stems, leaf veins and toothed edges are densely covered in white stinging hairs (trichomes). Contact with these hairs injects toxins, causing intense pain. New Zealand Plant Conservation Network+2Wikipedia+2

Primarily found in forest margins, riparian zones and open patches, ongaonga spreads via underground stems and regenerates after disturbance. Its stinging hairs protect it from many browsers. Ecologically, it plays a key role as the main host plant for the endemic Kahukura / New Zealand Red Admiral Butterfly (Vanessa gonerilla) larvae. Totopanen+1

Flowers appear from November to March in axillary clusters of male and female plants. Fruits are tiny brown achenes, single seeded dry fruits. Seedlings grow in moist forest floor conditions; mature plants may live for many years, continually regenerating from underground stems following disturbance. New Zealand Plant Conservation Network

Endemic to New Zealand, ongaonga occurs on both the North and South Islands and Stewart Island, in coastal to low-altitude forest and shrubland. Within the Brook Waimārama Sanctuary its presence contributes to structural complexity and supports biodiversity in the forest margin and stream-edge habitats.

Classified as Not Threatened, ongaonga has been cleared over much of its historic range, contributing to the decline of our endemic kahukura/red admiral.

Visitors walking through the Sanctuary’s forest edges may encounter ongaonga patches. Care should be taken not to brush against it — the sting is harsh.

🪶 The Māori word ongaonga also means “sting” or “irritation” — reflecting the plant’s painful spines.

Download the fact sheet PDF here

Our other residents

Check out some of the other incredible wildlife that call the Sanctuary home

Help us protect this Sanctuary

Volunteers are the backbone of the Sanctuary and donations, supporter fees, sponsorships allow us to continue our journey protecting the Sanctuary environment and building a place for rare and endangered New Zealand flora and fauna to thrive.

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Win prizes for your best summer photo at the Sanctuary 📸🏆☀️

This season, we want to see the Sanctuary through your lens — the bright light through the canopy, the textures of the forest floor, and the tiny details that make summer feel alive.

Enter our Summer Photography Competition (part of our Sanctuary Seasons series) and you could win:

🏆 Instant camera (Junior Photography winner)
 🌙 Family ticket to a guided night tour
 📰 Feature in our newsletter + social media
 🖼️ Printed display at the Visitor Centre

📅 Entries close 28 February - Submit your entries via our website: Link in bio

Photo credit: Helen Power - Entry from the spring photography competition

#BrookWaimāramaSanctuary #SanctuarySeasons #Ngahere #NaturePhotography #NZWildlife #NelsonTasman #VisitNelson #NZHikes #EcoTourismNZ #ConservationStorytelling
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Two cute to be true?

Brook Waimārama Sanctuary and @savethekiwinz teams have been busy over the past few days tracking and recapturing kiwi to remove their transmitters. Thanks to a huge team effort, all ten males were recaptured within just three days.

Some nest burrows held a surprise or two — in several cases a female was present, and a couple even contained chicks. One burrow amazed us all, with not one but two adorable chicks 😍

All chicks are fully independent at this stage of the season, and after quick health checks and transmitter removal, all adult kiwi were safely returned to their burrows.

This special footage was captured by kiwi handler Tamsin from Save the Kiwi, who led the transmitter removal mahi.

We estimate the 20 females and 21 males released in May last year have already produced around 10–15 kiwi pukupuku (little spotted kiwi) chicks in their very first breeding season — a strong sign the habitat is just right.

With transmitters now removed from all ten males, the kiwi are completely free, with no further handling needed. Annual kiwi call counts by staff and volunteers will help track the growing population across our 690 ha, ring-fenced, pest-free sanctuary.

Credit: Video courtesy of Tamsin Ward-Smith, Save the Kiwi

Thanks to our partnership with @terunangaotoa Ngati Toa and Save the Kiwi

 #kiwipukupuku #littlespottedkiwi #brookwaimaramasanctuary #nelson #thetopofthesouth #conservation #biodiversity #nativebirds #natureloversnz #newzealandwildlife #pestfree #ringfencedsanctuary #conservationinaction
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🎻 45 min string quartet concert at Brook Waimārama Sanctuary

Come and hear a dynamic young string quartet perform a 45 min concert at Brook Waimārama Sanctuary. We welcome everyone to come along, and bring anyone you think might be curious to hear some classical music in a relaxed environment.

The @antipodes.quartet is part of the Fellowship Ensemble Programme, a joint venture between the @adamchambermusicfestival, @newzealandstringquartet and @chambermusicnz, as a career-development experience offered to four of this country’s most promising young string players.

The Antipodes Quartet are Eden Annesley (violin), Mana Waiariki (violin), Tal Amoore (viola) and Lavinnia Rae (cello).

On this occasion, Brook Waimārama Sanctuary are welcoming everyone at local prices: Adult $15, Child $9; Family $35 (on the door)

Find out more: (Link in bio)

#BrookWaimāramaSanctuary #NelsonNZ #Whakatū #WhatsonNelson #NelsonTasman #LiveMusicNZ #ChamberMusicNZ #StringQuartet #ClassicalMusicNZ #AdamChamberMusicFestival #NewZealandStringQuartet #ChamberMusicNewZealand #FamilyFriendly #NatureAndCulture #SupportLocalArts
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STRATEGIC SUPPORTERS

NBS-Comm-2col-CMYK-Hires (002)

CONSERVATION CHAMPIONS

Come Visit Us!

651 Brook St, The Brook
Nelson 7010
New Zealand

(03) 539 4920

info@brooksanctuary.org.nz

OPEN HOURS

Monday: Closed
Tuesday: 9am – 5pm*
Wednesday: 9am – 5pm*
Thursday: 9am – 5pm*
Friday: 9am – 5pm*
Saturday: 9am – 5pm*
Sunday: 9am – 5pm*

The Sanctuary is open on all public holidays except Christmas Day.
*Last entry 4pm

PUBLIC TRANSPORT

NBus route 4 visits the Brook Sanctuary 6 days a week and departs from Nelson Airport. Click here for full timetable

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