Elymus multiflorus subsp. kingianus - critically endangered species listing

NSW Scientific Committee - final determination

The Scientific Committee, established by the Threatened Species Conservation Act, has made a Final Determination to list the grass Elymus multiflorus subsp. kingianus (Endl.) de Lange & R.O.Gardner as a CRITICALLY ENDANGERED SPECIES in Part 1 of Schedule 1A of the Act. Listing of Critically Endangered species is provided for by Part 2 of the Act.

 

The Scientific Committee has found that:

 

1. Elymus multiflorus subsp. kingianus (Endl.) de Lange & R.O.Gardner (family Poaceae) is a "somewhat tufted perennial. Culms slender, 30-100cm tall. Leaves narrow, 3-5 mm broad, flat or inrolled, finely scabrid on margin. Spikes 7-17 mm long, with 6-10 spikelets arranged alternately along axis. Spikelets 3-4 cm long (including awn), 3-9 flowered. Glumes unequal, acute; lower glume 9-11 mm long, 5-veined; upper glume 10-12 mm long, 7-9-veined. Lemma narrow, 8-10 mm long, setose-ciliate on margin, dorsally finely scabrid, especially on upper part and awn, with central vein broadening towards base into a coriaceous, round back; apex tapering to a slender scabrid awn, 8-14 mm long, straight or only slightly curved. Palea 8-9 mm long, setose-ciliate on margin" (Green 1994).

 

2. Elymus multiflorus is a widespread species from New Zealand and eastern Australia (de Lange et al. 2005). Elymus multiflorus subsp. kingianus was formally recognised as a subspecies by de Lange et al. (2005). It is restricted to Lord Howe Island in NSW and the Norfolk Island group (Green 1994; de Lange et al. 2005). On Lord Howe Island, it has previously been referred to as Agyropogon scabrum var. scabrum (Rodd & Pickard 1983), Agyropogon scabrum (Pickard 1983) and Elymus multiflorus var. kingianus (Conner 1994; Green 1994). Conner (1994) distinguishes Elymus multiflorus subsp. kingianus from New Zealand Elymus multiflorus plants by the multiplicity of small prickle teeth on the lemmas and on the glumes.

 

3. On Lord Howe Island Elymus multiflorus subsp. kingianus is restricted to two nearby locations (near Old Settlement Beach and Dawsons Point). At both locations it occurs at the intergrade between exposed basalt-derived rocky cliffs and a shrub zone that merges into littoral rainforest. Elymus multiflorus subsp. kingianus occurs in association with several grasses and herbs including Dichelachne crinita (Longhair plume grass), Poa poiformis, Senecio howeanus, Sporobolus virginicus (Sand couch), Tetragonia tetragonioides (New Zealand spinach) along with several shrub species, including Cassinia tenuifolia (Bully Bush), Dodonaea viscosa (Hopwood), Leucopogon parviflorus, Melaleuca howeana (Tea Tree) and Wollastonia biflora. The total extent of occurrence and area of occupancy are estimated to be less than 4 km2, as the entire distribution of the species in NSW falls within a single 2 x 2 km grid cell; the scale of assessment recommended by IUCN (2008).

 

4. Several recent surveys have only located from a few up to 30 individuals of Elymus multiflorus subsp. kingianus (Auld & Bower 2009). Surveys have been conducted over two years and across several seasons and it is likely that the total mature population size is less than 50 plants.

 

5. Elymus multiflorus subsp. kingianus is threatened by a number of exotic weeds that occur in the habitat of the species and compete for space and resources. These weeds include: Briza minor (Shivery grass), Bromus diandrus (Great Brome), Bromus cartharticus (Prairie grass), Conyza bonariensis, Ipomoea cairica, Paspalum dilatatum, Sonchus oleraceus (Common Sowthistle) and Sporobolus africanus (Parramatta grass).

 

6. Elymus multiflorus subsp. kingianus is also threatened by environmental and demographic stochasticity due to its very highly restricted distribution and extremely low population size.

 

7. Elymus multiflorus subsp. kingianus is listed as Critically Endangered on the Environment Protection and Biodiversity Conservation Act 1999.

 

8. Elymus multiflorus subsp. kingianus (Endl.) de Lange & R.O.Gardner is eligible to be listed as a Critically Endangered species as, in the opinion of the Scientific Committee, it is facing an extremely high risk of extinction in New South Wales in the immediate future as determined in accordance with the following criteria as prescribed by the Threatened Species Conservation Regulation 2002:

 

Clause 15

The geographic distribution of the species is estimated or inferred to be:

(a)

very highly restricted,

and

(d)

a projected or continuing decline is observed, estimated or inferred in:

 

(i)

an index of abundance appropriate to the taxon,

 

 

(ii)

geographic distribution, habitat quality or diversity, or genetic diversity.

 

 

Clause 16

The estimated total number of mature individuals of the species is:

(a)

very low,

and

(d)

a projected or continuing decline is observed, estimated or inferred in either:

 

(i)

an index of abundance appropriate to the taxon,

 

 

(ii)

geographic distribution, habitat quality or diversity, or genetic diversity.

 

 

Clause 17

The total number of mature individuals of the species is observed, estimated or inferred to be:

(a)

extremely low.

 

 

Dr Richard Major

Chairperson

Scientific Committee

 

Proposed Gazettal Date: 24/09/10

Exhibition Period: 24/09/10 - 19/11/10

 

 

References:

 

Auld TD, Bower S (2009) Assessment of the conservation status of Elymus multiflorus subsp. kingianus on Lord Howe Island. Unpublished report to NSW Scientific Committee.

 

Connor HE (1994) Indigenous New Zealand Triticeae: Gramineae. New Zealand Journal of Botany 32, 125-154.

 

de Lange PJ, Gardner RO, Sykes WR, Crowcroft GM, Cameron EK, Stalker F, Christian ML, Braggins JE (2005) Vascular flora of Norfolk Island: some additions and taxonomic notes. New Zealand Journal of Botany 43, 563-596.

 

Green PS (1994) Norfolk Island & Lord Howe Island. In: 'Flora of Australia' Vol. 49. Oceanic Islands 1. Canberra: AGPS

 

IUCN (2008) 'Guidelines for using the IUCN Red List Categories and Criteria. Version 7.0.' (Standards and Petitions Working Group of the IUCN Species Survival Commission Biodiversity Assessments Sub-committee: Switzerland). (http://intranet.iucn.org/webfiles/doc/SSC/RedList/RedListGuidelines.pdf).

 

Pickard J (1983) Rare or threatened vascular plants of Lord Howe Island. Biological Conservation 27, 125-139.

 

Rodd AN, Pickard J (1983) Census of vascular flora of Lord Howe Island. Cunninghamia 1, 267-280.

Page last updated: 28 February 2011