New Zealand Fairy Tern / Tara-iti

With a population of fewer than 40 birds and including a four year average (2009-2012) of just 9 breeding pairs, Sternula nereis davisae, the New Zealand fairy tern, (NZFT) is New Zealand's rarest endemic breeding bird.

Facts about the

New Zealand Fairy Tern

 

  • The New Zealand fairy tern is the smallest tern that breeds in NZ with adults measuring around 250mm in length and weighing a mere 70 grams
  • The average lifespan of a NZ fairy tern is less than 10 years (Ferreira et al 2005), however, two individuals are known to have survived into their 19th year.
  • Their nests are scrapes in shell-covered sand, usually above the spring high tide mark, on only four North Auckland beaches.
  • Unlike all other tern species breeding in NZ territorial waters, NZFT do not nest in conspicuous colonies. NZFT nests are often kilometres apart. At Mangawhai 2006-07, the minimum distance between any of the five breeding pairs' nests was c. 900 metres. (Brogtrop 2007)
  • Average incubation is 23 days.
  • Chicks fledge after three weeks.
  • Both sexes incubate their eggs.
  • Male birds provision themselves, their partner and their chicks.
  • Females source food for their chicks and themselves but rarely, if ever, for the male.
  • NZFT eggs are predominantly ovate and buff/sand coloured with tiny dark splotches, weighinig 12-13 grams and measuring 25mm X 35mm.
  • Some breeding females, who have repeatedly lost early clutches, have laid seven eggs (minimum 84 gms) in one season, which is more than their own body weight.
  • Breeding trios, ie two females and one male, have been recorded up until egg laying commences, at Papakanui (2001-02) and Waipu (2010-11).
  • A 2 egg nest was discovered at Mangawhai on Nov 3, 1999 by OSNZ volunteers Marie Smith, Diana Dombroski and Audrey Williams. Two dry chicks were spotted on Nov 19 and counting back from the hatching date, these eggs must have been laid October 29 or 30, making it a new early laying record. (Hansen 2000)

 

Threats to the New Zealand fairy terns' survival

 

  • Predation —introduced predators such as rats, dogs, cats, hedgehogs and mustelids (weasels, polecats, ferrets and stoats) prey upon eggs, chicks and adult birds.  Read more
  • Environmental events such as high tides, storms, and strong winds destroy nests or chicks.
  • Strong winds and persistent rain can impede the adults' ability to forage, sometimes causing them to desert their nests.
  • Disturbance from peoples' activities on beaches and in NZFT estuarine foraging areas during the breeding season.
  • Modification and /or loss of foraging, breeding and roosting habitat.

 

 

The "AGM" of New Zealand fairy terns, held at Huitoa Island (Kaipara Harbour) 23 April 2001. Just under half of the (then) total population attended. Guests included (in the background) South Island Pied Oyster Catchers.

Photo/James Colville

 

 

Post Breeding sightings of NZFT: 

Anyone visiting a wader roosting site on the Kaipara Harbour, or an East Coast estuary/breeding ground or ANY coastal shorebird roost site for that matter, is encouraged to LOOK for NZFT because juveniles can disperse widely.

If you see any NZFT, please record:

 

  • The place of the sighting.
  • The number of NZFT seen.
  • The date and time you saw the bird(s).
  • Your name and that of any other observer with you.

    If you have a camera with you, take a photo; if you have a telescope please try to read and record the bird(s)' leg bands. Write the bands you see down in the following order:

    Left leg first, top band and then any second band underneath it.
    Right leg , top band first and then any second band underneath it.

    Once you have recorded the above, please report your sighting to either

Dr Anthony Beauchamp, DoC, Whangarei - (09) 470-3312

e-mail: tbeauchamp@doc.govt.nz or

David Wilson at DOC, Warkworth (09) 425-7195 e-mail: dwilson@doc.govt.nz   

 

A list of literature pertaining to Australasian small terns is available on request from info@fairytern.org.nz