Threats
Verticordia spicata subsp. squamosa was declared as Rare Flora in June 1995. It is currently listed as
Critically Endangered (CR) under the Wildlife Conservation Act 1950 due to its restricted distribution, low
numbers of plants and continuing decline in the quality of habitat. V. spicata subsp. squamosa is listed as
Endangered under the Commonwealth Environment Protection and Biodiversity Conservation Act 1999
(EPBC Act).
It currently meets Red List (IUCN 2000) category ‘CR’ under criteria A4c;
Ba1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v); C2a(i) and D.
Clearing for agriculture around the Three Springs area began early in the 1900s, and has resulted in extensive
habitat loss. There has been additional widening of roads and clearing of road reserves in the Shires of Three
Springs and Mingenew in the past 10 years. The road reserve at Population 2 was graded in 1990 resulting in
the loss of several plants and significant reduction in the amount of available habitat. The main threats to the
taxon are poor recruitment, weeds, edge effects, rabbits, road and fence maintenance and inappropriate fire
regimes.
Interim Recovery Plan for Verticordia spicata subsp. squamosa
8
•
Poor recruitment is apparent at all populations, with juvenile plants germinating recently only at
Population 4b. It may be due to one or a combination of the following: low seed viability, an absence of
germination triggers such as fire or smoke, and the high level of weed competition or grazing. Seed
viability has been found to be variable but is generally low, and is particularly low in the populations that
consist of a single plant (Ginger 1999).
•
Weed invasion and competition are threats to all populations. Weeds suppress plant growth and
recruitment by competing for soil moisture, nutrients and light. They also exacerbate grazing pressure
and increase the fire hazard as grassy weeds produce large amounts of fuel annually.
•
Edge effects severely affect small populations, (especially narrow linear populations such as those on
road reserves) by exposure to influences from adjacent cleared land. In addition to the proximity of a
weed seed source, effects include increased wind speed, fertiliser and herbicide spray drift and runoff,
modified hydrology and altered disturbance regimes, including fire.
•
Degraded habitat is a threat to all populations. The lack of associated native vegetation increases the
likelihood that pollinators will be infrequent or absent. In addition, the lack of available habitat for
recruitment is of concern. Six of the nine populations occur on narrow road reserves in an extensively
cleared landscape.
•
Rabbit warren construction is causing soil disturbance at most roadside populations, in particular
Populations 1, 3 and 6a. Population 6b occurs on private property and the habitat also contains rabbit
warrens. Increasing nutrient levels and weeds introduced from rabbit droppings are also impacting on the
habitat of the taxon. Grazing is likely to impact on the establishment of Verticordia spicata subsp.
squamosa seedlings, thereby limiting natural recruitment.
•
Road, fence and firebreak maintenance activities threaten plants and habitat at road reserve
populations of Verticordia spicata subsp. squamosa. These include actions such as grading the road
reserves, chemical spraying, constructing drainage channels and mowing the roadside vegetation to
improve visibility. These disturbance events also often encourage weed invasion into adjacent habitat.
•
Inappropriate fire regimes would adversely affect the viability of populations, as seeds of Verticordia
spicata subsp . squamosa probably germinate following fire. If this is the case, the soil seed bank would
rapidly be depleted if fires recurred before regenerating or juvenile plants reached maturity and
replenished the soil seed bank. High fire frequency also results in a temporary increase in the availability
of nutrients, and this favours weed establishment (Panetta and Hopkins 1991). However, it is likely that
occasional fires are needed for reproduction of this taxon, but fire appears to be very infrequent in the
habitat of the known populations.
Interim Recovery Plan for Verticordia spicata subsp. squamosa
9
Summary of population information and threats
Pop. No. & Location
Land Status
Year/No. plants Condition
Threats
1. NNE of Three Springs
Shire road
reserve
1992 2
1995 6
1995 2
2000 5
2003 1
Moderate
Road and fence maintenance
activities, weeds, rabbits, agricultural
chemical drift, grazing by stock
through fences, drought
2. NE of Three Springs
Shire road
reserve
1992 3
1999 0
2000 0
Cleared
3. ENE of Yandanooka
Shire road
reserve
1994 1
1995 1
1997 1
1999 1
2000 1
2001 1
2003 0 [1]
Poor
Road maintenance activities, weeds,
agricultural chemical drift, rabbits,
drought
4a. E of Yandanooka
Shire road
reserve
1992 1
1995 0
1997 0
1999 0
Poor
Road maintenance activities, high
level weed competition, agricultural
chemical drift
4b. E of Yandanooka
Private property
1993 12
1995 10
1998 11
1999 4
2000 4 (2)
2001 5 (4)
2003 8 (2)
Moderate
Grazing by sheep, firebreak
maintenance, shading, drought
5. NE of Three Springs
Shire reserve
1995 2
Moderate
Quarrying, weeds
6a. NE of Three Springs
Shire road
reserve
1995 15
1999 10
2000 15
2002 15
2003 12
Moderate
Road maintenance activities, high
level weed competition, agricultural
chemical drift, rabbits, drought
6b. NE of Three Springs
Private property
1995 7
1999 7
2003 6
Moderate
Grazing by sheep, rabbits, degraded
habitat, drought
7. ENE of Yandanooka
Shire road
reserve
1996 1
1999 1
2001 1
2003 1
Poor
Road and fence maintenance
activities, high level rabbit
disturbance, drought, weeds,
agricultural chemical drift, shading
8. E of Yandanooka
Shire
(unconstructed)
road reserve
2000 1
2002 1
2003 1
Moderate
Road construction, fence and
firebreak maintenance activities,
weeds, agricultural chemical drift,
drought, rabbits
9T. N of Yandanooka
Private property
06.01 (8)
01.02 (8)
06.02 (6+21)
12.02 (4+19)
10.03 0+3 (3+8)
Moderate Drought,
rabbits
Numbers in brackets = number of juveniles. Plants in 9T listed by year of planting; ie, from 2001 planting + from 2002 planting.
Guide for decision-makers
Section 1 provides details of current and possible future threats. Any on-ground works (clearing, firebreaks,
roadworks etc) in the immediate vicinity of Verticordia spicata subsp. squamosa will require assessment.
On-ground works should not be approved unless the proponents can demonstrate that they will not have an
impact on the taxon, its habitat or potential habitat.
Interim Recovery Plan for Verticordia spicata subsp. squamosa
10
Critical habitat
Critical habitat is habitat identified as being critical to the survival of a listed threatened species or listed
threatened ecological community. Habitat is defined as the biophysical medium or media occupied
(continuously, periodically or occasionally) by an organism or group of organisms or once occupied
(continuously, periodically or occasionally) by an organism, or group of organisms, and into which
organisms of that kind have the potential to be reintroduced (EPBC Act).
Verticordia spicata subsp. squamosa is listed as Critically Endangered, and as such it is considered that all
known habitat for wild and translocated populations is critical habitat. This includes:
•
the area of occupancy of wild and translocated populations;
•
areas of similar habitat within 200 metres of populations, i.e. open mallee over low scrub on deep yellow
sands (these provide potential habitat for natural range extension);
•
corridors of remnant vegetation that link populations (these are necessary to allow pollinators to move
between populations and are usually road and rail verges); and
•
additional occurrences of similar habitat that do not currently contain the species but may have done so
in the past (these represent possible translocation sites).
Benefits to other species or ecological communities
Three Priority flora (Atkins 2003) species are known from the habitat of Verticordia spicata subsp.
squamosa. These are Acacia lanceolata (Priority 2), Calytrix purpurea (Priority 2) and Pityrodia viscida
(Priority 3). In addition, recovery actions such as weed control or planting of buffer vegetation at V. spicata
subsp. squamosa populations will help to protect the ecological community in which the populations are
located.
International obligations
This plan is fully consistent with the aims and recommendations of the Convention on Biological Diversity,
ratified by Australia in June 1993, and will assist in implementing Australia’s responsibilities under that
Convention. V. spicata subsp. squamosa is not specifically listed under any international treaty, and therefore
this plan does not affect Australia’s obligations under any other international agreements.
Role and interests of indigenous people
Indigenous communities interested or involved in the regions affected by this plan have not yet been
identified. The Aboriginal Sites Register maintained by the Department of Indigenous Affairs does not list
any significant sites in the vicinity of these populations. Implementation of recovery actions under this plan
will include consideration of the role and interests of indigenous communities in the region, and this is
discussed in the recovery actions.
Social and economic impacts
Some populations of Verticordia spicata subsp. squamosa occur on private land and negotiations will
continue with regard to the future management of these populations. The implementation of this recovery
plan has the potential to have some social and economic impact, where populations are located on private
property or other lands that are not specifically managed for conservation such as road reserves. Recovery
actions refer to continued liaison between stakeholders with regard to these areas.
Evaluation of the plan’s performance
CALM will evaluate the performance of this IRP in conjunction with the Geraldton District Threatened Flora
Recovery Team and the Moora District Threatened Flora Recovery Team. In addition to annual reporting on
progress with listed actions and comparison against the criteria for success and failure, the plan is to be
reviewed within five years of its implementation.
2.
RECOVERY OBJECTIVE AND CRITERIA
Objectives
The objective of this Interim Recovery Plan is to abate identified threats and maintain or enhance in situ
populations to ensure the long-term preservation of the species in the wild.
Interim Recovery Plan for Verticordia spicata subsp. squamosa
11
Criteria for success: The number of individuals within populations and/or the number of populations have
increased by ten percent or more over the five year period of the plan.
Criteria for failure: The number of individuals within populations have decreased by ten percent or more
over the five year period of the plan.
3. RECOVERY
ACTIONS
Existing recovery actions
All relevant land managers have been notified of the location and threatened status of the taxon. The
notification details the Declared Rare status of Verticordia spicata subsp. squamosa and the associated legal
responsibilities.
Declared Rare Flora (DRF) markers have been installed at Populations 1, 3, 6a and 7. These alert people
working in the area to the presence of significant flora, and help to prevent accidental damage. Awareness of
the significance of these markers has been promoted to relevant land managers such as local government
authorities.
Populations 4b and 6b on private property were fenced in 1997 to prevent sheep grazing and trampling plants
and habitat. Rabbit-proof enclosures were installed over the juveniles at Population 4b in May 2000. These
were replaced with larger enclosures in December 2003.
Spot weed control was undertaken at Populations 3 and 6a as part of a weed control research project (Obbens
1997). Both sites were spot sprayed with Fusilade in August 1996, achieving patchy but generally good
control of target weeds including wild oats (Avena sp.) and annual veldt grass (Ehrharta longiflora). Care
was taken to avoid herbicide drift on to non-target plants during spraying. No native species were damaged
by the weed control, and this includes several monocot species and Austrostipa elegantissima, a native grass
present in the habitat. Small outbreaks of broadleaf weeds occurred once grasses were reduced. Weed control
with Fusilade and spotspraying of Roundup was implemented at Populations 3, 4a, 4b and 7 in May 2000.
Some hand removal of wild oats has since been undertaken at Populations 3 and 7, and these populations
were weed-free in January 2001.
Research into the reproductive biology, seed bank dynamics and seed germination physiology (particularly
the response to smoke) was undertaken as part of an Honours project on V. spicata subsp. squamosa and V.
albida (Ginger 1999). Details of his findings about number of flowers produced, seed viability, soil stored
seed reserves and germination response to smoke were reported in his thesis.
In 2000 CALM staff from Geraldton District attempted to stimulate seed germination with the application of
smoke granules in association with weed control. Quadrats were established around each plant in June 2000,
and smoke granules applied. Seedlings were evident by August 2000, although by November it was apparent
that none of these were of V. spicata subsp. squamosa. It is thought that germination failure is at least
partially due to the dry winter experienced that year and the following year.
Approximately 3,700 seeds have been stored at CALM’s Threatened Flora Seed Centre (TFSC), collected
from Populations 1, 4b, 6a and 7 over the years 1996, 1997, 1998 and 2002. The initial germination rate of
this seed was found to range from 7% to 100%, and after one year in storage ranged from 33% to 100%
(unpublished data A. Cochrane
3
). More seed was collected in December 2003 from Populations 1, 4b, 6a, 6b
and 8. Seed was unavailable for collection due to plant absence at Populations 2, 3 and 4a, a lack of
flowering at Population 7, and plant immaturity at Population 9T. The quantity and viability of these seed
collections is unknown as they have not yet been processed. The seed will be stored at the TFSC until sent to
the Botanic Gardens and Parks Authority (BGPA) nursery to be propagated for translocation.
This taxon has proved very difficult to propagate. Trial grafting of Verticordia spicata subsp. squamosa onto
rootstock of Chamelaucium uncinatum was undertaken in 1994, but none of the 58 grafts were successful.
Only ten plants resulted from 916 cuttings struck by the BGPA nursery in 1999 and 2001. Seven of those
died within 7 months, and the remaining three plants were planted into Population 9T in 2002. An unknown
3
Anne Cochrane, Manager, CALM's Threatened Flora Seed Centre
Interim Recovery Plan for Verticordia spicata subsp. squamosa
12
number of seeds have been sown and smoke treated, with 18 germinants surviving to juvenile stage. All of
these were also included in the translocation in 2002 (A. Shade
4
, personal communication). Historically,
some plants were planted into the Botanic Garden, but there is evidence that these were of the V. comosa
x
spicata subsp. squamosa hybrid (George 2002).
A translocation was developed by staff from CALM’s Geraldton District and implemented in cooperation
with the Mingenew Herbarium Group, part of the Mingenew Land Conservation District Committee
(LCDC). Assistance with funding was provided by the Threatened Species Network program of the World
Wide Fund for Nature. The translocation site is on remnant vegetation on private property, which is
protected by a Conservation Covenant. The owner of this land is associated with the Mingenew LCDC. The
first planting of eight juveniles occurred in June 2001. All translocates are planted with individual rabbit-
proof enclosures and drip-lines from a gravity-fed watering system that is switched on over summer.
However, there have been repeated failures of the control box of this watering system, resulting in extended
periods over summer with no delivery of water to translocates. Four direct seeding plots were also fenced
and seeded. Treatments tested were smoke (applied as vermiculite), raking, and both smoke and raking.
Seeded plots were not watered over summer. No seedlings were observed in the seeded plots at any time,
although monitoring continued to October 2003. An additional 21 juveniles were planted in June 2002, all
with individual rabbit-proof enclosures and driplines. Failures of the watering control box recurred over the
summers of 2002 and 2003. The landowner supported the project with occasional manual watering at these
times. Survival of the translocates is recorded in the following table.
Survival
of
Verticordia spicata subsp. squamosa after translocation
A double-sided information sheet has been produced, and includes a description of V. spicata subsp .
squamosa, its habitat, threats, recovery actions and photos. This will be reprinted, and continue to be
distributed to the community through local libraries, wildflower shows and other avenues. It is hoped that
this may result in the discovery of new populations, and will raise community awareness of the value of
native flora.
Staff from CALM’s Moora and Geraldton Districts regularly monitor all populations of this taxon. Liaison
with local residents led to the confirmation of a new population - Population 8.
The Moora District Threatened Flora Recovery Team and the Geraldton District Threatened Flora Recovery
Team are overseeing the implementation of this IRP.
Future recovery actions
Where populations occur on lands other than those managed by CALM, permission has been or will be
sought from appropriate land managers prior to recovery actions being undertaken. The following recovery
actions are roughly in order of descending priority; however this should not constrain addressing any of the
priorities if funding is available for ‘lower’ priorities and other opportunities arise.
1.
Coordinate recovery actions
The Geraldton District and Moora District Threatened Flora Recovery Teams will coordinate recovery
actions for Verticordia spicata subsp . squamosa and other Declared Rare Flora in their districts. They will
include information on progress in their annual reports to CALM’s Corporate Executive and funding bodies.
4
Amanda Shade, Horticulturalist, Botanic Garden and Parks Authority
2001 plantings
2002 plantings
Year
No.
surviving %
survival
Year
No.
surviving %
survival
Initial (Jun 2001)
8
Jan 2002
8
100
Jun 2002
6
75
Initial (Jun 2002)
21
Dec 2002
4
50
Dec 2002
18
86
Oct 2003
3
38
Oct 2003
8
38
Interim Recovery Plan for Verticordia spicata subsp. squamosa
13
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