As we sat beside Kiwiriki creek
near it’s confluence with the sea, we heard a strange ‘booming’ noise. I
thought it might be a bittern, although it was not as loud or as long as
bittern ‘booms’ I’ve heard before. Anyway this pesky noise set in motion
a plan to kayak from Fitzroy to the Kiwiriki at dawn the following
weekend to search for bitterns in the salt marsh. This plan was carried
out, albeit that thanks to a cold westerly I arrived on site a bit later
I kayaked around there for a bit, and had a ‘walk’ through the salt
marsh, but neither heard nor saw any bitterns. I tied up in some large
old mangroves on the southern shore of the bay, but there is not as much
tall reedy vegetation (bittern habitat) as I expected. However, I had
the pleasure of watching an adult pied shag (Phalacrocorax varius)
teaching its juvenile how to catch fish! They were racing about in 30 cm
of clear water in the mangroves, chasing parore. I was sitting in the
kayak not paddling, and one of them passed right under me. Later I went
up Coffin’s Creek and again drew a blank on bitterns.
Adult Pied Shag at Kiwiriki creeek
On the positive side I saw a pair of reef herons (Egreta sacra) on the
Kaiaraara mud flats. They are seen fairly frequently at Okupu (Emmy
Pratt), and I occasionally see one on the east coast near Awana. Seeing
a pair together suggests possible nesting in the area. Reef herons are
‘Nationally vulnerable’ in New Zealand (MisKelly et al. 2008) although
the species is quite widespread in Australia and the Pacific. We have
only the grey form –a more dramatic white version of the same species
occurs in the Pacific.
Shag skull - it demonstrates the
efficiency of the shag jaws
as a fish catching structure and the large eye socket.
are rare on GBI but judging by the occasional report of their booming
calls they are not extinct. Their decline is due partly to habitat loss
(swamp drainage) and partly to predation on eggs and juveniles.
The Trust would appreciate any reports of sightings or of their
distinctive calls. There is a recording of such on Radio
National’s website if you wish to hear an original at
• Sir Walter Laury Buller’s painting of
the New Zealand Bittern or Matuku (botaurus poeciloptlius) extracted
from his landmark text “A History of the Birds of New Zealand”.
A NEW RECORD FOR GREAT BARRIER
While in Kiwiriki Bay I nearly tipped up the boat pulling out a
different-looking brown seaweed over a metre long. Subsequent
consultation showed this to be Sargassum scabridum, a new
species on Great Barrier. This find simply demonstrates that
there is still plenty to discover about the island’s flora, and
brings the total number of marine algae (seaweeds) here up to
Sargassum scabridum from the
northern shore of Kiwiriki Bay. The photo shows the end of
a frond which was c. 1.2m long.
Some of the old mangroves (Avicennia
marina) in Kiwiriki Bay. All photos by John Ogden.