Tag Archives: rare

Would you mine a rare population?

21 April 2013 – 2.28pm

The Escarpment Mine on the Denniston Plateau has been tentatively approved by the Environment Court, subject to suitable mitigation plans. One of the issues that may be under consideration is what to do about the site’s population of the Sticherus tener umbrella fern.

Scoop news report: “…tentative nod for Denniston mine plan”.

Sticherus tener has a conservation ranking in New Zealand of Nationally Critical. That is as rare as you can get without being extinct.

The umbrella fern Sticherus tener at a site within the planned Escarpment Mine on the Denniston Plateau. Photo Leon Perrie. © Te Papa.

The umbrella fern Sticherus tener at a site within the planned Escarpment Mine on the Denniston Plateau. Photo Leon Perrie. © Te Papa.

Destroying a population of a species so threatened in New Zealand has to be weighed against the economic benefits of the proposed mine. Of course, the Denniston area’s natural values are far greater than this one fern species. A factor in any consideration specific to Sticherus tener is that it is common in Australia. In that context, it is similar to the white heron or kōtuku (Ardea modesta), which graces our $2 coins. The white heron is also Nationally Critical in New Zealand, but Secure Overseas. Would New Zealanders accept a development destroying part of the white heron population in New Zealand?

Our paper detailing the status of Sticherus tener in New Zealand has just been published. Sticherus tener was known in New Zealand only from one 1980s record from Fiordland. Department of Conservation staff have recently made additional records from Fiordland. Furthermore, Te Papa’s botanists realised that some of the plants in the Stockton and Denniston areas are actually Sticherus tener.

Abstract from the New Zealand Journal of Botany.

Email me if you would like a pdf of the paper.

Te Papa’s collections of Sticherus tener, with more photos.

Our paper also recognises Sticherus urceolatus in New Zealand for the first time. Sticherus urceolatus is closely related to Sticherus tener, and also is Nationally Critical in New Zealand while being common in Australia. Sticherus urceolatus occurs at Stockton (but not Denniston), near Takaka, and apparently in Fiordland.

Te Papa’s collections of Sticherus urceolatus, with more photos.

The umbrella fern Sticherus urceolatus at Stockton. The frond segments of this species arise at a pronounced angle, while those of Sticherus tener are close to 90 degrees. Other differences are detailed in our paper. Photo Leon Perrie. © Te Papa.

The umbrella fern Sticherus urceolatus at Stockton. The frond segments of this species arise at a pronounced angle, while those of Sticherus tener are close to 90 degrees. Other differences are detailed in our paper. Photo Leon Perrie. © Te Papa.

Populations of Sticherus tener and Sticherus urceolatus in the northern South Island had previously been mistakenly attributed to Sticherus flabellatus. We now believe that Sticherus flabellatus does not occur in the South Island, but it is common in the northern North Island. When the Denniston population was erroneously attributed to Sticherus flabellatus, an issue for the proposed mine was the destruction of a population at the southern limit of a species common in New Zealand. The correct identification of the Denniston population as Sticherus tener, Nationally Critical in New Zealand, makes the conservation implications for the proposed mine more serious.

Te Papa’s collections of Sticherus flabellatus.

It was an internet photo that first alerted me to the possibility of Sticherus at Denniston being more complicated that everyone thought. I was trying to find more information about Denniston for our 2012 field work surveying for the then-undescribed Gleichenia inclusisora tangle fern; this Naturally Uncommon species also occurs at Denniston. I came across a report containing a photo from Denniston labelled “Sticherus flabellatus”. I was immediately sure that the photo did not show Sticherus flabellatus, but instead some other species of Sticherus. However, determining the correct identity as Sticherus tener took several more months. This involved a revision of existing herbarium specimens from the northern South Island that were labelled “Sticherus flabellatus” (all actually either Sticherus tener or Sticherus urceolatus), DNA sequencing, and field work to visit the sites ourselves.

Blog post on our 2012 field work in the South Island, targeting Sticherus and other ‘problem’ ferns.

Blog post on the recently described new species of tangle fern, Gleichenia inclusisora.

Interestingly, the Forest and Bird-organised BioBlitz of the Denniston Plateau in 2012 did not detect Sticherus tener. That this medium-sized fern was missed by such a concerted effort to document the area’s biodiversity is a cautionary indicator of how difficult it is to make well-informed land management decisions.

Forest and Bird’s BioBlitz at Denniston.

By Leon Perrie | Posted in Biodiversity, Collections Online, Ferns, Field trips, Plants | Also tagged , , , , , , , , , | Comments (3)

Rare success – rediscovery of several bryophyte species

19 December 2011 – 11.54am

Te Papa’s botanists made several significant finds during their explorations accompanying the recent Bryophyte and Lichen Workshop.

Led by Research Associate Peter Beveridge and Research Fellow Patrick Brownsey, the moss Dicranoweisia spenceri was found in some abundance at the site we investigated within Tongariro National Park.  This is great news because this is only the second known living population of Dicranoweisia spenceri, after its recent rediscovery at Arthur’s Pass by Landcare Research’s Allan Fife.  More sites around Tongariro National Park now need to be searched for Dicranoweisia spenceri to determine how widespread it is there.

The moss Dicranoweisia spenceri on a branch of a beech tree, Tongariro area. Photo Leon Perrie, © Te Papa.

Close-up image of Dicranoweisia spenceri.

Interestingly, Peter realised the importance of some of his collected* specimens only after we had returned home and he examined them with a microscope – the moss Hampeella pallens from the Bay of Plenty and an undescribed species of Lopholejeunea liverwort near Mahia.  In addition to a 1983 record from the Kaimai Ranges, Hampeella pallens was known from the Bay of Plenty but without a precise locality.  It has a current threat classification of Nationally Critical, one step above Extinct.

It is indicative of the challenges that these tiny plants present that we did not recognise the Hampeella pallens and Lopholejeunea in the field.  Bryophyte identification can take considerable skill and often necessitates microscopic examination.  One of the goals of the annual Bryophyte and Lichen Workshop is to share and develop those skills.

Previous blogs on the Workshop: 2009, 2010.

The liverwort Petalophyllum preissii (centre), Kaikoura. It is similar to Petalophyllum hodgsoniae, which we looked for unsuccessfully in Morere Springs Reserve. Photo David Glenny, © Landcare Research.

We also had some search failures.  We didn’t find the distinctive Petalophyllum hodgsoniae, a liverwort that looks a bit like a fingernail-sized lettuce.  It is known from a single 1947 collection, and is regarded as Nationally Critical.  Visitors to the forest behind the thermal pools at Morere, near Mahia, might keep an eye out for it during spring and early summer.

Our observations, be they positive or negative, provide data for the Department of Conservation sponsored Bryophyte Expert Panel to re-assess the Threat Classification of New Zealand’s bryophytes.

The 2010 evaluation of the threat status for New Zealand’s mosses and liverworts.

More about how Te Papa’s botanists contribute to plant conservation.

We also looked for a Porella liverwort known from a mid-twentieth century record on the coast at Whakamahi near Wairoa.  Unfortunately the area is now devoid of native forest, so there wasn’t much to search.  Many mosses and liverworts have specific habitats.  If the habitats are destroyed, so too are the inhabitants.  Which is why accurately documenting the distribution of New Zealand’s biota, no matter how small the plant or animal, is so important – surely we do not want to inadvertently consign more species to extinction. 

Thanks to Allan Fife and David Glenny, bryologists at Landcare Research’s herbarium at Lincoln, for their expertise and support.

* made under a Department of Conservation permit.

By Leon Perrie | Posted in Field trips, Plants | Also tagged , , , , , , , | Comments (4)

How Te Papa contributes to plant conservation

20 November 2011 – 4.13pm

In the next two weeks, some of Te Papa’s Botany staff will be looking for several poorly known mosses and liverworts.

For instance, the moss Dicranoweisia spenceri was recorded more than 60 years ago from near Mount Ruapehu but it hasn’t been reported from there since – is it still there? We’re going to check.

A specimen of the moss Dicranoweisia spenceri in Te Papa’s collection. This species has a conservation ranking of “Data deficient”; that is, not enough is known about its occurrence to classify the level of threat it faces. © Te Papa.

Conservation managers need to know what is rare and what is not. It allows them to prioritise (increasingly) stretched resources to those plants and animals at most risk of extinction.

New Zealand’s herbaria (collections of dried plant specimens) collectively have over one million specimens (Te Papa has c. 250000). These collections voucher, or provide physical proof, of what plants are in New Zealand, what they look like, and where they occur. Many species occur commonly and over large areas, but many others are only known from a few sites, placing them at risk of extinction.

Te Papa’s botany collection.

New Zealand Virtual Herbarium – an aggregate database of NZ’s herbaria.

One million specimens sounds a lot. But there’s still huge gaps in the documentation of New Zealand’s native plants (not to mention adventive and cultivated plants).

Mosses and liverworts pose a particular challenge. They’re small and underappreciated, and there’s far fewer people capable of identifying them compared with bigger plants.

What are mosses and liverworts?

There are about 520 mosses and 600 liverwort species in New Zealand. Yet in the recent threat evaluation of these groups, 135 taxa/entities are listed as “Data Deficient”. That is, not enough is known about them to even rate how threatened they are.

The 2010 evaluation of the threat status for New Zealand’s mosses and liverworts.

Which is why the Bryophyte and Lichen Workshop is so important. This is an annual gathering of people – amateurs and professionals, beginners and experts – interested in mosses, liverworts, and lichens. This year the Workshop is based in Matawai, between Opotiki and Gisborne. Three staff and a Research Associate from Te Papa are taking part. There’s very few previous records of mosses and liverworts from the Matawai area, so we’ll be collecting a specimen of every species we find, including common species. But we’ll have a close eye out for those regarded as Data Deficient, both during the Workshop and at targeted sites during our travel there and back.

I’ll let you know what we turn up.

Previous blogs on the Workshop: 2009, 2010.

By Leon Perrie | Posted in Field trips, Plants | Also tagged , , , , , , , | Comments (1)

Delight and Disaster in the Rubbish Heap

24 March 2011 – 3.29pm

I’m always keen to add to the number of plants I can recognise. Weeds are a profitable group in that respect.

One of the species of poroporo, Solanum aviculare. Photo © Leon Perrie.

Recently my wife pointed out an interesting looking organic rubbish heap on the grounds of Massey University that was home to an odd-looking Solanum. Imagine my delight when, on closer inspection, I found it to be not a weedy exotic but a real indigenous treasure: Solanum aviculare.

Solanum aviculare is one of two similar species known as poroporo. The other is Solanum laciniatum, which is very common and widespread through New Zealand. Solanum aviculare, on the other hand, is on the Threatened Plants lists as “At Risk/Declining”. I have never knowingly seen it before, so I was very excited!

Handily, at this rubbish heap the two species of poroporo were growing together, facilitating easy comparison. Although their leaves were strikingly different here, the best way to distinguish them is by their flowers: the petals of S. aviculare are less fused and more deeply cut than those of S. laciniatum.

The two poroporo side-by-side. Solanum laciniatum is on the left, Solanum aviculare on the right. Photo © Leon Perrie.

Flowers of the two poroporo. Solanum laciniatum is on the left, Solanum aviculare on the right. Photos © Leon Perrie.

The DISASTER comes because a week after taking these pictures, this rubbish heap was “cleaned up” – an unfortunate demise for this rarity! Hopefully we can find more S. aviculare locally.

Unripe fruit of poroporo, Solanum laciniatum. Photo © Leon Perrie.

Both poroporo species have similar fruit, which can be eaten when they are ripe (when orange, with bursting skin). However, they’re poisonous when green and unripe, so be wary! They belong to the same genus as tomatoes, potatoes, and black nightshade, and the same family as deadly nightshade. It’s a minefield of nutrition and toxicity.

Interestingly, both Solanum aviculare and S. laciniatum occur in Australia, where they are known as kangaroo apple.

By Leon Perrie | Posted in Plants | Also tagged , , , , , | Comments (5)

More rare maidenhair spleenwort.

16 March 2009 – 11.18am

The rare, tetraploid maidenhair spleenwort  (Asplenium trichomanes subsp. quadrivalens) has only recently been rediscovered in New Zealand.  Several people have contacted me with possible additional sightings. As described by the Scoop website, Jack Ritchie had a maidenhair spleenwort self-sow on a rock used to construct a water feature in his nursery, Tree Guys, in Otane.

Jack took us to the local farm where the rock was sourced from, and without too much effort we found a good population: about 70 plants growing on limestone outcrops in pasture.

Asplenium trichomanes subsp. quadrivalens

Tetraploid maidenhair spleenwort.

These rocks are host to several plants of tetraploid maidenhair spleenwort.

These rocks are host to several plants of tetraploid maidenhair spleenwort.

Lara Shepherd (Massey University) and I collected a few samples, and confirmed through analyses of their spores and DNA that they were the tetraploid maidenhair spleenwort rather than the common hexaploid maidenhair spleenwort.

DNA sequence data. The highlighted position is one of several DNA sites found by Lara that differ between the tetraploid (upper two samples) and octoploid (lower two samples) maidenhair spleenworts.

DNA sequence data. The highlighted position is one of several DNA sites found by Lara that differ between the tetraploid (upper two samples) and hexaploid (lower two samples) maidenhair spleenworts.

There is plenty of similar habitat in the region, so the tetraploid maidenhair spleenwort could well be much more widespread. We need to find more than 250 individuals to lift it out of the Nationally Critical conservation category, which I am hopeful we will achieve with more searching.  Ideally, it will turn out to be sufficiently common that it doesn’t even need to be on the threatened list.

Thanks to Jack Ritchie and everyone else who has contacted me about the maidenhair spleenwort. I have several other promising leads to follow-up when I am next able to escape the office.

If you would like to see a tetraploid maidenhair spleenwort for yourself, then visit Jack Ritchie. He is a very knowledgeable and enthusiastic plant-person, and his tetraploid maidenhair spleenwort is the only one I know of in ‘captivity’. Jack’s Tree Guys nursery is in Otane, on the main road between Waipukurau and Hastings.

By Leon Perrie | Posted in Ferns, Field trips, Plants | Also tagged , , , , , | Comments (1)

Identifying maidenhair spleenwort ferns.

24 February 2009 – 2.00pm

The maidenhair spleenwort is a spleenwort fern (Asplenium) that (supposedly) looks like a maidenhair fern (Adiantum, see below). The 600 or so of the world’s spleenworts are characterised by having their reproductive structures in lines away from the margins of their fronds’ undersides.

asplenium_trichomanes_sori_edit

The reproductive structures (the sori, made up of the sporangia which contain the spores, and their protective indusia) of maidenhair spleenwort, on the underside of a frond.

Two maidenhair spleenworts occur in New Zealand. They look very similar, but one has four sets of chromosomes (tetraploid) and the other six (hexaploid). This difference in chromosome number means they cannot interbreed. In New Zealand, the hexaploid is common, but the tetraploid is rare, only being known from the Hawke’s Bay, and only recently being rediscovered. Outside New Zealand, the hexaploid is rare, being known from only a few places in Australia, while the tetraploid is common and widespread around the world.

Tetraploid and hexaploid plants of maidenhair spleenwort.

Tetraploid and hexaploid plants of maidenhair spleenwort.

distributionmaps

The distributions of the maidenhair spleenworts in New Zealand.

  

Maidenhair spleenworts are most commonly found on limestone rock. They can be out in the open, or under semi-shade, but usually in fairly dry conditions. They often hold their fronds erect, whereas other ferns growing from rock usually have pendulous fronds.

Open, limestone outcrops; a habitat for maidenhair spleenworts.

Open, limestone outcrops; a habitat for maidenhair spleenworts.

The taxonomy of New Zealand’s maidenhair spleenworts is still being researched. The tetraploid may be referable to Asplenium trichomanes subsp. quadrivalens. The correct scientific name for the hexaploid, the most common maidenhair spleenwort in New Zealand, is presently unclear.

Maidenhair spleenworts can be distinguished from other New Zealand ferns by the combination of their typical spleenwort reproductive structures (see above), and their frond stems which are almost black, almost smooth (without hairs and with only a few scales), and undivided (i.e., the stems do not branch). Similar-looking  ferns in New Zealand are described below.

 
Necklace fern, Asplenium flabellifolium.
A spleenwort or Asplenium fern like the maidenhair spleenworts can be most obviously distinguished from the maidenhair spleenworts by its green stem.

 

asplenium_flabellifolium1

Necklace fern, Asplenium flabellifolium.

Maidenhairs, Adiantum.
The maidenhairs are most obviously distinguished from the maidenhair spleenworts by the branching stems of their fronds. The Small maidenhair (Adiantum diaphanum) can sometimes have unbranched frond stems, but it, like all maidenhairs, can be reliably distinguished by having the reproductive structures on the margins of their fronds’ undersides.

A maidenhair fern, Adiantum fulvum.

A maidenhair fern, Adiantum fulvum.

Button fern, Pellaea rotundifolia.
The brown and scaly frond stems and reproductive structures on the margins of their fronds’ undersides distinguish button ferns from the maidenhair spleenworts.

The Button fern, Pellaea rotundifolia.

The Button fern, Pellaea rotundifolia.

Blechnum ferns.
Like most Blechnum ferns, Creek fern (Blechnum fluviatile) and Lance fern (Blechnum chambersii) have very different looking fertile and sterile fronds. Those fronds that are making spores have much narrower segments, are held more erect, and are black or brown (they are not dead despite their lack of greenness!).

blechnum_fluviatile_chambersii

Blechnum chambersii or Lance fern (left) and Blechnum fluviatile or Creek fern (right). The blue arrows indicate fertile fronds.

 

We are still interested in learning more about the maidenhair spleenworts in the southern North Island (south of, and not including, the Waikato). I would be very grateful for notification (and a photo) if you think you have found maidenhair spleenwort in the southern North Island. Please either email (leonp@tepapa.govt.nz), phone (04 381 7261), or write me (Leon Perrie, Te Papa, PO Box 467, Wellington).

By Leon Perrie | Posted in Ferns, Plants | Also tagged , , , | Comments (5)

Rare fern rediscovered.

21 October 2008 – 4.45pm
I’m one of the Botany Curators at Te Papa, and ferns are one of my specialties.  New Zealand has about 200 native ferns, and some of them are very rare.  We recently rediscovered one rare fern that had been ‘lost’.  I was beginning to wonder if it had become extinct, but fortunately it has not.  Still, the known total of individuals is still only 9, and this population is only a goat-lunch away from extinction!
Me, on top of the Ruahine Ranges. No rare ferns sighted up here, but interesting nonetheless.

Me, on top of the Ruahine Ranges. No rare ferns sighted up here, but interesting nonetheless.

The rediscovered fern is a maidenhair spleenwort.  It had been definitively identified from just three New Zealand sites, all in Hawke’s Bay, and all dating to the 1950′s.  The localities of these three sites were not precisely recorded, and no one I talked to knew of a living population.   I enlisted the help of the Manawatu Botanical Society to search one of these sites (the most precise one, which involved searching several square km rather than several tens of square km).  I wasn’t very optimistic, given the amount of time since it had been previously collected and that I had already looked at a number of similar Hawke’s Bay sites.  But, we found it – 9 plants in one very small area. 

There is another maidenhair spleenwort in NZ, and it is quite common.  These two maidenhair spleenworts look similar, but they have different chromosome numbers; the common one has six sets of chromosomes while the rare one has four sets.  This kind of difference is usually treated at the subspecies or even species level in ferns.   Unfortunately, the present taxonomy, or formal scientific naming, for these ferns is not adequate.  We hope to sort this out in the next year or so.  They have both been called Asplenium trichomanes, but this fern does not occur in NZ (at least when interpreted in a narrow sense).  The rare maidenhair spleenwort in NZ has also been called Asplenium trichomanes subsp. quadrivalens; whether this is correct remains to be established.
Maidenhair spleenwort. This is the rare species, but the common one looks very similar.

Maidenhair spleenwort. This is the rare species, but the common one looks very similar.

The two maidenhair spleenworts usually occur on or near limestone.  They can be distinguished from all other ferns in NZ by their undivided, black, almost smooth stems, and by having their reproductive structures in lines away from the margins of the undersides of their leaves.  This particular arrangement of the reproductive structures characteristics all of the spleenwort (Asplenium) species, of which there are about 20 in NZ (and some 600 in the world).

I’d be interested in learning of additional maidenhair spleenwort sites in Hawke’s Bay.  Both species of maidenhair spleenwort have been recorded from the Hawke’s Bay, so any new finds may be the rare or the common species.  I would need to closely inspect them to be sure.  But, please, do not remove them from the wild!  Email (leonp@tepapa.govt.nz) or phone (04 381 7261) me the locality details.

Te Papa’s Collections Online includes a photo of a maidenhair spleenwort specimen collected from the Hawke’s Bay in 1881 (it’s the common species, rather than the rare one).  The New Zealand Plant Conservation Network also has more information about maidenhair spleenworts.

By Leon Perrie | Posted in Collections Online, Ferns, Plants | Also tagged , , , , | Comments (3)
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