More Surprise Finds of Fissidens Berteroi in Auckland City
The water ways of Auckland City are now largely given over to naturalised plants, and sad to say, mostly seriously polluted. Over the last few summers botanists Dr(s) Peter de Lange and Rhys Gardner have been documenting the indigenous vegetation of waterways draining into the Waitemata Harbour along the Three Kings lava flow. This lava flow, the largest in Auckland City, extends from the ruins of the Three Kings volcanic vents north and west into the Waitemata Harbour. Several water ways drain this area, and these, along with a series of associated springs have been investigated by the pair.Despite the rank weed growth, rats, and rubbish choking the waterways they have been surprised at the indigenous flora that still persists in these areas.
A number of regionally significant finds have been made. However, the most impressive from a conservation view point are several large populations of Fissidens berteroi, the largest New Zealand species in the genus, and one of the most threatened. Previously, in 2005, de Lange had found this moss in Auckland gracing the eel tank at Kelly Tarltons Underwater World where it had appeared on a log that had been collected from an “urban Auckland stream”. Frustratingly, staff couldn’t say where this stream was, as the person who had placed the log had left their employment, and no records had been kept.
In the wild Fissidens berteroi had previously been recorded from Auckland at two sites, a small drainage pipe near Onehunga – all that remains of a formerly important natural spring that had supplied water for that suburb, and from Motions Creek, near Jaggers Bush, Westmere. The Onehunga site still persists thanks to careful water management but the Motions Creek site was believed to have died out not long after Auckland City Council removed willows from the stream banks in 2005.
De Lange was the first to notice Fissidens berteroi in Auckland Zoo during a visit in November 2007 when he fortuitously noticed a strand floating near the zoo outlet for the creek. Not long later he and Dr Gardner found a few plants near the upper end of the creek. It seemed clear that Fissidens should be in the zoo section of the creek. Permission from the zoo was sought and Mr Hugo Baynes Zoo Horticultural Curator agreed to allow the pair to wander the zoo portion of the creek. Within minutes several large populations were found, mostly in and around the stone bridges that cross the creek, but also on boulders near small seepages and springs that enter the waterway.
The zoo staff are of course delighted with the find, as it is a first for them to have a natural population of an endangered species occurring within their grounds. The zoo is currently refurbishing their threatened indigenous biota displays for a major exhibit “Te Wao Nui o Tane”, and in the process had been actively seeking suggestions from the Department of Conservation as to what threatened flora they should show case. A naturally occurring threatened moss, and an aquatic one at that, is certainly an unexpected bonus, and one that provides numerous useful opportunities to educate on the importance of Auckland’s freshwater waterways.
This find along with another found by de Lange and Gardner elsewhere within the City adds to other recent (2007) discoveries of the moss on the Chatham Islands and in the Wairarapa. Despite these discoveries Fissidens berteroi is still hardly secure and in Auckland remains mostly at threat from ongoing willow tree clearance, which increases light levels entering the waterways, leading to massive algal blooms, which seem to choke out the moss.
Posted: 27/01/2008