Herpetofauna of Four Remnant Bushland Isolates in the City of Nedlands, Perth

2008·3.7 MB·English

by  P F Berry

HERPETOFAUNA OF FOUR REMNANT BUSHLAND
ISOLATES IN THE CITY OF NEDLANDS, PERTH
By P.F. BERRY
11 Burwood Street, Nedlands, W.A. 6009 ([email protected])
and O.F. BERRY
School of Animal Biology (M092), The University of WA, Crawley 6009.
ABSTRACT
The herpetofaunas of four small, isolated remnant
bushlands and a nearby urban garden in metropolitan
Perth are documented. Shenton Bushland (21 ha.) was
sampled over eleven consecutive years between 1994 and
2005 and 22 species (4 frogs, 3 snakes and 15 lizards) were
recorded. Underwood Avenue Bushland (31 ha) was sampled
over two years - 1998/1999 and 2000/2001 and 20 species (3
frogs, 3 snakes and 14 lizards) were recorded. Hollywood
Reserve (6.5 ha) was sampled in 2001/2002 and 10 species (1
snake and 9 lizards) were recorded. A small, unnamed
bushland isolate on Monash Avenue (0.75 ha), was sampled
in 2001/2002 and 4 lizard species were recorded. Five lizard
species were recorded from the urban garden over a 26 year
period. No species differing from those on the Shenton
Bushland list was recorded at the other bushlands. Thirteen
of the 18 reptile species recorded (72%) are entirely
dependent on native bushlands, as is the Turtle Frog
(Myobatrachus gotildii), one of four frog species recorded.
Clearly these urban bushland fragments play an important
role in preservation of the biodiversity in the western
suburbs of Perth. Trapping effort at Shenton Bushland was
20,628 trap-days over 10 consecutive years before the gecko,
Strophurus spinigerus, was recorded 597 days (5 years) after it
had been assumed that 100% of the assemblage at Shenton
Bushland had been recorded.
INTRODUCTION Others pointed out that the
Two decades ago Hopkins and Banksia woodlands of the Swan
Saunders (1987) stressed the need Coastal Plain were diminishing
for ecological studies to provide rapidly in area, yet had been
empirical data on the role of neglected scientifically and
remnant bushlands in the urgently required study to
conservation of native biota. achieve conservation goals and
27
to develop management strat¬ its nearest neighbour. Shenton
egies (e.g. Hopper and Burbidge Bushland (21 ha), an A Class
1989; Hopkins and Griffin 1989; Reserve, was sampled over 11
How and Dell 1993). consecutive years between 1994
Despite the rapid pace of and 2005. Underwood Avenue
development in the Perth Bushland (31 ha), owned by the
metropolitan area, only a small University of Western Australia,
number of systematic studies of was sampled over two years -
the vertebrate assemblages of 1998/1999 and 2000/2001.
urban bushland remnants have Hollywood Bushland (6.5 ha), a C
been published to date (e.g. Class Reserve, was sampled in
Cooper 1995; How 1998; How and 2001/2002. An unnamed isolate
Dell 1989; Maryan 1993; Turpin on Monash Avenue (0.75 ha),
1991). As an illustration of this referred to as the Hospital
deficiency in documentation, of Bushland and owned by the Sir
58 bushland sites from the Charles Gairdner Hospital, was
Spearwood dune system assessed sampled in 2001/2002. In
in ‘Perth’s Bush Forever' (Anon. addition, herpetofauna records
2000), 34 (59%) had no records of over 26 years from a nearby
the fauna. urban garden are available. These
four remnants and the garden
Results to date suggest that even
are situated between two of
small urban reserves are valuable
Perth’s major bushlands - Kings
for preserving reptile assemblages
Park (321 ha) and Bold Park (362
(How and Dell, 2000) and the
ha). We show that urban
composition of the fauna
bushland fragments in the Perth
depends in part on major geo¬
metropolitan area support
graphical features such as dune
diverse herpetofaunal assem¬
formation and position relative
blages compared to a suburban
to the Swan River (How and Dell
garden. This result highlights the
1994). However, the high trap¬
critical role of urban bushlands
ping efforts required to record
for the preservation of faunal
some species (e.g. 12 years for
biodiversity in the region.
Pletholax gracilis in Bold Park,
How pers. comm, and eleven
years in this study for Strophurus
STUDY SITES
spinigerus in Shenton Bushland)
suggests that knowledge of All four study sites are on aeolian
herpetofaunal assemblage distri¬ sands of the Spearwood Dune
butions in the Perth metro¬ system and none has free¬
politan area may still be standing water. They are
incomplete. representative of the Karrakatta
In this study we describe the Central and South vegetation
herpetofauna of four urban complex of predominantly open
bushland remnants, none of forest and low woodland of
which is more than 900m from Eucalyptus gomphocephala — E.
28
rnarginata — Corymbia calophylla wealth property along two of its
and woodland of E. rnarginata borders makes the area an
-
Banksia species. According to effectively larger bushland
Perth’s Bush Forever, 18% of this remnant. It is situated on a ridge
complex remains as native (max. height 34m AHD) and is
vegetation on the Spearwood approximately half way between
Dunes in Perth Metropolitan Perth’s two largest inner urban
Region (Anon. 2000). bushlands - Kings Park and Bold
Park (Figure 1).
The Shenton Bushland (an A
class reserve vested in the City of Prior to its vesting, parts of
Nedlands in 1996) covers an area Shenton Bushland were severely
of 20.9 ha, of which 19.7 ha is degraded by the dumping of
bushland. However, adjacent rubbish and weed invasion,
bushland on State and Common¬ whilst other parts were in
Figure 1. Positions of Bold Park, Kings Park, Underwood Avenue Bushland,
Shenton Bushland , Hollywood Reserve and Monash Bushland.
29
relatively good condition (Anon. although structurally similar to
1996). Perth’s Bush Forever rates Shenton Bushland, was charac¬
the vegetation condition as >50% terised by having generally larger
Very Good to Excellent; <50% and more abundant Jarrah and
Good to Degraded with areas of more large living Tuarts, pro¬
severe localised disturbance viding a denser eucalypt canopy,
(Anon. 2000). Prior to com¬ as well as extensive thickets of
mencement of this study this Banksia prionotes. The last fire
bushland had not had a major prior to the sampling for this
fire for at least a decade; there study was in January 1988 (Don
was a small fire along the King pers. comm.). A fire in
northern border in 1992 (Don January 2002, which burnt
King pers. comm.). The most approximately 95% of Under¬
recent fire burned approxi¬ wood Bushland severely damaged
mately 65% of the reserve during those thickets surveyed.
the study in 1997. Few large E.
The Hollywood Reserve is a 6.5ha
gopiphocephala (Tuart) remain
bushland remnant bordered by
alive and most large E. marginata Karrakatta cemetery, except for
(Jarrah) have been cut out.
the south and north-east sides of
Significant rehabilitation, par¬
the reserve where there are
ticularly weed reduction, has
suburban roadways. It is
been undertaken continuously
managed by the City of Nedlands
by the Nedlands City Council
and the Friends of Hollywood
and the Friends of Shenton
Reserve Inc. The fauna and
Bushland Inc. since 1994.
vegetation have been described
The Underwood Avenue Bush¬ by Cousin et al (2000) on the basis
land is owned by the University of a 3 week survey in December
of Western Australia which plans 1999. Weed control as well as
to subdivide it for a housing replanting of non-local native
development. It covers an area of plants has occurred in this
32.1 ha, of which 31.5 is remnant reserve. Frequent small fires have
native vegetation and is situated also contributed to its
approximately 600 metres degradation.
directly north of the Shenton The Hospital Bushland is a
bushland. Small fragmented areas remnant of approximately 0.75
of native vegetation persist on ha of E.marginata/Banksia wood¬
private property between the two land owned by the Sir Charles
bushlands. Perth’s Bush Forever Gairdner Hospital. Apart from
rates the vegetation condition as moderate weed invasion, its
>50% Very Good; <50% Good to vegetation and floristics appear to
Degraded with areas of severe be typical E.marginata/Banksia
localised disturbance (Anon. woodland and in moderately
2000). In 1998/99 and 2000/01 good condition, though they
(when the fauna surveys were have not been described. In 2001
undertaken) this bushland, the University of Western Aus-
30
tralia built a new dental school to Total number of days trapped
the east of the bushland which over this 11 year span was 1230.
has reduced insolation. Sub¬ Site One, at the highest point of
sequent to the building activity the bushland, was characterised
the Hospital has undertaken by a thicket of Dryandra sessilis
some rehabilitation work and that became progressively more
restricted public access. mature and dense over the study
The urban garden, on a 1000m2 period. This site was not burnt in
the 1996 fire, but was sprayed the
block, has been cleared of natural
vegetation for at least 70 years. same year with herbicide which
eliminated perennial veldt grass
(Ehrhartci calycina). Site Two was
SAMPLING selected as being typical of the
Eucalyj)tus-Banksia woodland. It
Animals were captured using 20L
was burned in 1996 which also
plastic bucket pit traps
had the effect of reducing veldt
(dimensions 30 x 50 cm) with 4m
grass.
long, 30cm high flywire mesh
drift fences. Checks of pitfall
Underwood Avenue Bushland
traps were made daily and
animals released at their point of Two sites were sampled using pit
capture after identification and traps. Traps were arranged as two
measurement. High trapping line transects, one of 9 traps and
efforts were used as How (1998) one of ten traps, with traps
has shown that an intensive spaced ca. 10 metres apart.
trapping program of over 960 Trapping was continuous from 7
pit-days was necessary to record October 1998 to 14 March 1999
at least 80% of the herpetofaunal (149 days) and 10 September 2000
assemblage in Bold Park. to 25 February 2001 (155 days).
Coordinates of pitfall traps are Line 1 ran parallel to Selby Street
listed in Table 3. Herpetofauna through a low, flat area of sparse
from the urban block were Eucalyptus-Banksia woodland
recorded opportunistically by overlying heath. The second line
P.F.B. from swimming pool ran up the slope parallel to
casualties and opportunistic Underwood Avenue through
captures since 1981. dense Eucalyptus-Banksia wood¬
land and included Banksia
Shenton Bushland prionotes thicket.
Two sites were sampled using pit-
Hollywood Reserve
traps. At each site traps were
arranged as 3 x 3 trap grids with Ten pit traps were used, 5 in the
traps spaced ca. 5m apart. northern and 5 in the southern
Trapping began in 1994 and was sectors of the reserve. The traps
continued during the spring, were located as close as possible
summer and autumn months to positions used and mapped by
(September to March) until 2005. Cousin et al (2000) in their 1999
31
Table 1. Herpetofauna recorded from the Shenton Bushland (SHB) between 1994
and 2005, the Underwood Avenue Bushland (UAB) in 1998/1999and 2000/2001,
Hollywood Reserve (HR) in 2000/2001 and Monash Avenue Bushland (MAB) in
2000/2001. Also shown is the herpetofauna recorded from Kings Park (KP) (data
from How and Dell 2000 and unpubl.), and Bold Park (BP) (data from How 1998
and How and Dell 2000).
SPECIES SITE
REPTILES SHB UAB HR MAB BP KP
Skinks (Scincidae)
Cryptoblepharus plagiocephalus 116 25 23 - 27 37
Ctenotus fallens 515 239 32 1 463 756
Ctenotus australis 171 36 - - 59 62
Cyclodomorphus celatus - - - - 12 3
Hemiergis quadrilineata 503 342 37 4 998 164
Lerista elegans 61 95 28 - 176 26
Lerista lineopunctulata - - - - 164 40
Lerista praepedita 7 13 2 - 17 14
Menetia greyii 107 54 58 23 40 185
Morethia lineoocellata - - - - 1 1
Morethia obscura 142 80 - - 2 21
Tiliqua rugosa 32 8 5 - 43 6
Legless Lizards (Pygopodidae)
Aprasia repens 86 37 28 7 19 72
Lialis burton is 41 13 - - 84 15
Qekkos (Qekkonidae)
Diplodactylus alboguttatus - - - - 1 -
Diplodactylus polyophthalmus - - - - - 1
St roph u rus spin igerus 1 - - - 114 -
Christ in us marinoratus 55 8 9 - - 24
Dragons (Agamidae)
Pogona minor 28 23 - - 32 69
Rankinia adelaidensis - - - - 19 -
Monitors (Varanidae)
Varanusgouldii 5 1 - 4 2
Varanus tristis ; 1
Blind Snakes (Typhlopidae)
Ramphotyphlops australis 29 22 1 (cid:9632) 27 8
Fixed Front-Fanged Snakes (Elapidae)
Pseudonaja affinis 6 2 - - 1 1
Simoselaps bertholdi 28 9 - - 122 3
Simoselaps bimaculatus - - - - 10 3
Simoselaps calonotus - - - - 16 _
Simoselaps fasciolatus - - - - 7
S imoselaps sem ifasciat us - - - - 22 -
Subtotal reptile taxa 18 17 10 4 26 23
Subtotal reptile individuals 1933 1007 223 35 2480 1514
32
Table 1 (cont.)
SPECIES SITE
SHB UAB HR MAB BP KP
AMPHIBIANS
Crinia insignifera 1 - - - - -
Heleioporus eyrei 42 1 - - 71 -
Limnodynastes dorsalis 4 5 - - 146 -
M yobatrachus gouldi 97 45 - - 25 5
Subtotal amphibian taxa 4 3 0 0 3 1
Subtotal amphibian individuals 144 51 242 5
Total number of species trapped 22 20 10 4 29 24
Total number of individuals 2258 1058 223 35 2722 1519
Total days trapped 1230 290 123 123 398 173
Total number of trap-days 22140 5510 1230 246 9552 8703
Individuals/10 trap-days 1.02 1.92 1.81 1.42 2.85 1.75
study. Trapping was undertaken and the Hospital Bush lands
between the 16 September 2001 where the reptile taxa were
and 29 February 2002 (123 days). reduced to 10 and 4 species
respectively, all of which also
Monash Avenue Bushland occur in Shenton and Under¬
wood Avenue Bushlands (Table
Two pit traps were used. Trap¬
ping was undertaken between 16 1).
September 2001 and 29 February The urban garden in the vicinity
2002 (123 days). of the bushlands contained only
5 lizard species - 4 skinks (H.
quadrilineata, M. greyii, C.
RESULTS
plagiocephalus, L. elegans) and 1
Species Richness gecko (C. marmoratus).
A total of 22 herpetofauna
Reptiles
species was recorded in this
study, comprising 18 reptile and Catch per unit of effort for the
4 frog taxa. Apart from one herpetofauna taxa recorded in
additional gecko species all the bushlands is presented in
(Strophurus spinigerus) and one Table 2. Over the eleven con¬
additional frog species (Crinia secutive years sampled at
insignifera) recorded at Shenton Shenton Bushland, by far the
Bushland, the same 17 species of most captures were of the skinks
reptiles and 3 species of frogs Ctenotus fallens and Hemiergis
were recorded at Underwood quadrilineata. With fewer
Avenue Bushland. No frogs were captures, but recorded in all
recorded from the Hollywood eleven years sampled were
33
Aprasia repens, Ctenotus australis, Frogs
Cryptoblepharus plagiocephalus, The Turtle Frog M. gouldii, the
Lialis burtonis, Lerista elegans, most frequently captured frog,
Menetia greyii, Morethia obscura, was recorded in all eleven years
Christinas marmoratus, Simoselaps sampled in Shenton Bushland. H.
bertholdii, and Tiliqua rugosa. R. eyrei (9 years) and L. dorsalis (6
australis was recorded in ten of years) were recorded in low
the eleven years sampled. Least
numbers and all were sub-adults,
captures, and recorded irregu¬
while only a single specimen of
larly over the period sampled
C. insignifera was recorded (Table
(number of years in brackets)
2). Presumably these latter three
were of Pogona minor (8), Lerista taxa were dispersing from nearby
praepedita (6), Pseudonaja affinis (5) water bodies where breeding had
and Varanusgouldii (1). The gecko, occurred. Of the frogs recorded,
Strophurus spinigerus, (1) was only only the Turtle Frog M. gouldii is
recorded in the eleventh year at
resident and breeds in Shenton
Site 1 which is in a maturing
and Underwood Bushlands. Its
Dryandra sessilis thicket.
distribution within these bush¬
The capture rate for most species lands shows a clear preference for
in the Underwood, Monash and the crests of ridges. At Shenton
Hospital bushlands was approxi¬ Bushland 123 (95%) of a total of
mately twice those recorded for 130 specimens captured were at
Shenton Bushland in the same Site One, the higher of the two
years (Tables 1 and 2). C. fallens and sites. At Underwood Avenue
H. quadrilineata were the most Bushland 100% of specimens (45
frequently captured species in individuals) were recorded at
Shenton and Underwood Bush- Line 2 in which the traps
lands, but A. repens and M. greyii represented a transect from the
were the most frequently bottom to the top of a ridge. 50
captured species in Hollywood % of the specimens recorded
and Monash Avenue Bushlands. were in the top two pit-traps
One hundred and fifteen days towards the ridge crest. No
(2070 trap days) elapsed before specimens were captured at Line
80% of the Shenton Bushland 1, which runs along a swale.
herpetofauna was recorded,
whereas only 19 days (361 trap
DISCUSSION
days) were required to achieve
this at Underwood Avenue The vertebrate fauna of the
Bushland (However, if Varanus majority of urban bushland
gouldii is excluded, the effort to remnants on the Spearwood
achieve 100% of the species in dune system has received little or
common was similar at Shenton no study (Anon 2000). This limits
and Underwood Bushlands our understanding of the dis¬
(3816 and 3834 trap days tribution of species on the Swan
respectively). Coastal Plain, and the role that
34
bushland fragments play in recorded and may reflect habitat
preserving regional biodiversity. changes that have occurred over
We conducted a long-term time (maturation of the Dryandra
trapping study to document the sessilis thicket and protection
herpetofauna of urban bushland since reserve status was
fragments within the western acquired). However, it also may
metropolitan region of Perth. We also be because the taxon is
show that bushland fragments extremely uncommon or very
contain biodiverse herpeto- untrappable This record further
faunal assemblages, and the demonstrates that uncommon
majority of these species do not species, which are often the focus
occur in urban gardens. of conservation and manage¬
ment strategies (e.g. Milne et al
The importance of long-term
2000), may be missed by short
trapping effort to adequately
term or low intensity surveys. A
document herpetofaunal assem¬
more detailed analysis of our
blages is well accepted (e.g. How
catch per effort results, includ¬
1998, Thompson et al 2007). How
ing an additional year of
(1998) recorded 80% of the
sampling will be presented
herpetofaunal assemblage at
elsewhere (O.F. Berry and P.F.
Bold Park after 960 pit-days (40
Berry in prep.).
days over 2 years) and 100% of
the fauna was assumed to have The Turtle Frog M. gouldii is
been reached after 4,512 pit-days clearly dependant on persistence
(188 days over 4 years), there of native bushland for its
being no additions for 5,040 survival in the Metropolitan
additional pit-days (210 days over area. Within these bushlands its
3 years) thereafter. However, this apparent preference for high
assump-tion was negated by the ground towards the crest of
sub-sequent recording of the ridges needs to be taken into
legless lizard Pletholax gracilis after account. Although recorded at
12 years (How pers. comm.). Simi¬ low levels of abundance, the
larly, with the trapping effort at other frog species recorded may
Shenton and Underwood benefit from native bushlands
Avenue Bushlands (20,628 trap- for feeding and as dispersion
days over 10 years and 5,510 trap- corridors.
days over two years respectively) In addition to the species
it seemed unlikely that additions recorded in this study, ten
would be made to the herpeto¬ reptile species - two skinks,
faunal assemblages until the (Cyclodomorphus celatus and Lcrista
gecko, Strophurus spinigerus, was lineopunctulata), one agamid
recorded at Shenton Bushland (Rankinia adelaidensis), two geckos
after 11 years. This was 597 days (5 (Diplodactylus alboguttatus and
years) after it had been assumed Diplodactylus polyophthalmus), one
that 100% of the assemblage at varanid (Varanus tristis) and four
Shenton Bushland had been elapid snakes (Brachyurophis
35
B), re
Ahe CQ
nd (Ute w S< siKCnoN OrNnN" ooo oOo ooo iinn ooo ooo ooo moOins
ao
hlen CON
Buss d o<N PZ.
y ell oo
ersited c <ON
nivhad fXfl On NCNO in iCnN rn ON <n
B), Uch. S CO CN rCnN oo in N"
Hr
SMa
d (
ushlanober to ONr<OS oomCN iNNn7" N0NO0“ 0dN“ OOodns
O) at Shenton B by species Octon Bushland - ie Oct-March icrnno rOrCnnNn NCdNO 0Oin0n NmCNO ONCNn" »n
atch per unit of effort (trap nights xlOO and Monash Avenue Bushland (MAB)t than the maximum recorded at ShentNIGHT (XlOOO) Trap days exclude Sept OOOOoS2ooCoBNNoNNn' rfXXC^fnOl Croi0i—OinnnnNs arCvndO omo.Cvd—NdNoCN+nONONOds“l nco°tOQni- oNrSo0C_NnOOO0~ ro——n NrOowr0rONOC4dnnOoO0OS1ssi 'OC2O2'O rOnTN+n+7il-1 OodI mnicocCriON4nOnnnNodn!” cimvinrnTd• -i Cn200n—+N4014i 5CN srCrinrnirouCc4OnnnnO-Nd1i-jj SSVtdVc-O3-j oO§dcNr4nnOst 8^ OCmiv1Nr—4nnNdOs!1 rCoC,VrnNNn, im0roCN+nnNd-• r^Onns
of cHR)danAP
Table 2. Comparison Hollywood Reserve (axa were more abunNB MEAN IS NO/ TR <(cid:9632)a. -.~6SQxoO?S-Tn. .^-OSa•UOjoxxj i 3 2 X• bvS5-io "T2e£a3 n(cid:9632)-aQiQCs-X, 2• 2bC<x>o
t
36