Although forests cover only 5% of Australia's landmass, they
support almost half of the terrestrial vertebrates, including 77%, 53%
and 33% of all mammal, frog and reptile species, respectively (Lamb and
Smyth 2003). Furthermore, 75% of these are endemic forest species (Lamb
and Smyth 2003).
Timber harvesting is a significant form of disturbance in those
Australian forests where it is practiced and its effects on fauna
remains contentious (e.g. Recher 1985; Lindenmayer and Franklin 2002;
Calver and Wardell-Johnson 2004). Mammal responses and associations to
timber harvesting have received considerable attention both in Western
Australia (WA) and elsewhere in Australia and include studies of small
terrestrial mammals (e.g. Barry 1984; Kavanagh and Webb 1998; Lunney et
al. 2009), bats (e.g. Lloyd et al. 2006; Adams et al. 2009) and
particularly arboreal mammals (e.g. Kavanagh and Bamkin 1995; Laurance
and Laurance 1996; Lindenmayer et al. 1999; Lindenmayer 2000; Wayne et
al. 2006). Reviewers of this information include Lindenmayer (1994),
Gibbons and Lindenmayer (2002; hollow-users), Lindenmayer and Franklin
(2002), Lindenmayer and Hobbs (2004; plantation forests) and Lindenmayer
et al. (2008; salvage logging).
Vertebrates that use hollows are considered to be especially
sensitive to timber harvesting in eucalypt forests (e.g. Christensen
1997; Abbott and Whitford 2002; Gibbons and Lindenmayer 2002;
Wardell-Johnson et al. 2004; Kavanagh and Stanton 2005). About 75% of
mammals in the forests of south-west WA are considered to use hollows to
some extent (Christensen 1997) and are similarly recognised as an
important habitat element for many other taxa. As a consequence, hollows
and the fauna that use them have been the primary focus of studies on
the effects of silviculture on fauna in south-west WA. These include
investigations of the distribution, abundance and characteristics of
hollow logs (Faunt 1992; Williams and Faunt 1997) and tree hollows
(Whitford and Williams 2000, 2002; Whitford 2001, 2002), and their
predicted availability to hollow users (Abbott and Whitford 2002).
Arboreal and semi-arboreal mammals, including the ngwayir, Pseudocheirus
occidentalis (Inions et al. 1989; Jones et al. 1994a,b; Jones and
Hillcox 1995; Wayne et al. 2000, 2005a, 2006; Jones 2004), koomal,
Trichosurus vulpecula hypoleucus (Inions et al. 1989; Jones and Hillcox
1995; Morris et al. 2001; Wayne et al. 2005a, Wayne unpublished data)
and wambenger, Phascogale sp. WAM M434, formerly P. tapoatafa (Rhind
1996a,b, 1998, 2002, 2004; Rhind and Bradley 2002), have also been the
subject of detailed investigation.
In southern NSW, many small terrestrial mammals and reptiles
(including arboreal, terrestrial and fossorial species) were not
affected by logging or recovered quickly (Webb 1995; Goldingay et al.
1996; Kavanagh and Webb 1998). However, some reptiles were adversely
affected at various periods after logging in coastal forests (Lunney et
al. 1991; Webb 1995), but others in montane forests had significantly
higher abundances at logged sites (Goldingay et al. 1996). In East
Gippsland, no reptile species appeared to be disadvantaged by timber
harvesting and one species may have benefited from forest regrowth, but
reptile species diversity was adversely affected by harvesting in the
lowland forests and favoured in the wet forests (Alexander et al. 2002).
Responses of frogs to disturbance are poorly known in Australia
compared with elsewhere (Gillespie 2002; Hazell 2003). The few studies
undertaken indicate a pattern of response broadly consistent with other
taxa; some species are disadvantaged and some are favoured. In NSW, frog
species richness and abundance were positively associated with logging
disturbance (Lemckert 1999), but other species were considered to be
disadvantaged (Lemckert 1999; Gillespie 2002; Kavanagh and Stanton 2005;
Penman et al. 2005, 2008). Responses within the same taxon may also
vary. For example, Crinea signifera is a well-studied frog that appears
relatively tolerant to disturbance associated with silviculture (Baker
and Lauck 2006; Lauck 2006), but its responses to logging varied
(Kavanagh and Webb 1998; Lemckert 1999; Kavanagh and Stanton 2005; Lauck
Published empirical studies on terrestrial vertebrates in relation
to silviculture in south-west WA are limited but do include reports on
several mammals: mardo, Antechinus flavipes (Wardell-Johnson 1986),
numbat, Myrmecobius fasciatus (Friend 1994), chuditch, Dasyurus
geoffroii (Serena et al. 1991; Morris et al. 2003), woylie, Bettongia
penicillata and quenda, Isoodon obesulus fusciventor (Morris et al.
2003). Some bats have also been recently studied (Webala et al. 2010,
2011). Reviews of the fauna responses to silviculture in south-west WA
include those by Nichols and Muir (1989), Wardell-Johnson and Nichols
(1991), Christensen (1997) and Calver and Dell (1998a,b). There are
currently no peer-reviewed publications that quantitatively relate
effects of silviculture on reptiles or amphibians in Western Australian
forests, and up until recently were severely lacking for elsewhere in
Australia (e.g. Gillespie 2002; Hazell 2003).
Overall, responses of terrestrial vertebrates to the disturbance
associated with timber harvesting vary. Some species are favoured,
others disadvantaged, and in many cases there is no apparent effect or
insufficient data to reliably assess responses (e.g. Woinarski and
Fisher 1995; Goldingay et al. 1996; Kavanagh and Webb 1998; Lindenmayer
and Franklin 2002; Kavanagh and Stanton 2005).
The jarrah (Eucalyptus marginata) forest of south-west WA supports
a particularly high level of biodiversity (Wardell-Johnson and Horwitz
1996), and as such represents one of the most important Australian
bioregions for the conservation of numerous species that have
disappeared from much of their former ranges (National Land and Water
Resources Audit 2002). Although considerable research into disturbance
ecology has been carried out in the region (Wardell-Johnson and Nichols
1991), the lack of appropriate studies of the causes of declining
populations of native species seriously hampers effective conservation
of local biodiversity (Christensen and Abbott 1989; Nichols and Muir
1989; Christensen 1997; Calver and Dell 1998a,b; Friend and Wayne 2003;
Wardell-Johnson et al. 2004).
FORESTCHECK is an integrated monitoring project designed to inform
forest managers about changes and trends in key elements of forest
biodiversity associated with management activities in Western Australia
(Abbott and Burrows 2004; McCaw et al. 2011). The initial focus has been
on monitoring the effects of silvicultural treatment in jarrah forest at
replicated grids and at a regional level in relation to vascular plants,
cryptograms, epigeous macrofungi, invertebrates and vertebrates. While
FORESTCHECK is designed as a long-term monitoring program, it also
provides an opportunity to investigate fauna responses to silviculture.
Therefore the main aim of this study is to determine whether terrestrial
vertebrate associations in jarrah forest subjected to silvicultural
treatments differ among treatments and relative to 'external
reference' areas, these being areas of comparable mature forest
that has either never been harvested or not harvested for more than 40
y. The response measures investigated included abundance of some
individual species, overall species richness and abundance, and
community structure. As such this is the first published account of an
empirical study of the associations of frogs, reptiles and some mammal
species with silviculture in a Western Australian forest.
Details of methods common to this study and other biota groups
monitored in FORESTCHECK are provided by McCaw et al. (2011). Briefly,
48 monitoring grids were established in four jarrah forest ecosystems:
Jarrah South (JS), Jarrah North West (JNW), Jarrah North East (JNE) and
Jarrah Blackwood Plateau (JB) (McCaw et al. 2011). Grids were
established in two locations in the JNW ecosystem--the central (JNW-C)
and northern (JNW-N) subregions to cover its extensive north--south
range. All grids from one ecosystem (or location) were monitored in any
one year, with different ecosystems surveyed in successive years
(2001-2006) (Table 1). Treatments were shelterwood (12 grids), selective
cut (3 grids), gap release (14 grids), coupe buffer (4 grids) and
external reference forest (15 grids). Coupe buffers were uncut temporary
reserves within areas of harvested forest. External reference grids were
established in mature forest in conservation reserves, national park and
state forest, and included forest that had never been harvested (8
grids) or had not been harvested for at least 40 y (7 grids). All
silvicultural treatments (shelterwood, selective cut and gap release)
had been undertaken since 1988, and in each ecosystem were stratified
across time since harvest (McCaw et al. 2011). Descriptive statistics
for coupe buffer and selective cut treatments are presented but not
included in comparative analyses due to the low representation of these
treatments. Through timber harvesting, the basal area of shelterwood
grids was reduced by an average of 45% and of gap release grids by 70%,
and the average size of gaps was 9 ha. At the time of monitoring the
average basal area of grids in the reference, shelterwood and gap
release treatments was 41, 22 and 16 [m.sup.2] [ha.sup.-1] respectively
(McCaw 2011). The attributes of each monitoring grid, including history
and time since last treatment (silviculture and/or prescribed fire), and
detailed descriptions of the forest ecosystems, silvicultural treatments
and other site attributes are included in McCaw et al. (2011).
Terrestrial vertebrate surveys
At each of the 48 monitoring grids 15 pitfall traps were arranged
in three transects of five pitfalls spaced 20 m apart along transects
and 25 m between transects (see Fig. 3 in McCaw et al. 2011). Each
pitfall trap comprised a 20 L plastic bucket (25 cm diameter x 40 cm
deep) with a 5-m-long fly-wire 'drift' fence located centrally
across the bucket. The drift fence was kept vertical with stakes to a
height of at least 20 cm high above ground level and was buried to a
depth of at least 5 cm where possible. A polystyrene meat tray or egg
carton and a handful of sand and leaf litter were provided as shelter in
the bottom of each bucket.
Fifteen wire cage traps (20 cm x 20 cm x 45 cm) were arranged in
three transects of five traps each spaced 50 m apart both within and
between transects (see Fig. 3 in McCaw et al. 2011). Traps were located
in sheltered positions with thick hessian bags overlaid to provide
protection to captive fauna and baited with a variant of
'universal' bait (peanut butter, rolled oats and emu oil).
Pitfall and cage traps were run simultaneously on all grids in each
ecosystem for four consecutive nights in both spring
(November--December) and autumn (March-May). All captive animals were
identified and processed at the point of capture, and released
immediately afterward. Mammals were fitted with individual identity ear
tags and their sex, weight and breeding status recorded.
Dunnarts (Sminthopsis spp.) were aggregated at the genus level
given the difficulties of unequivocally distinguishing between S.
gilbertii and S. griseoventer by field identification of live specimens.
Similarly, 'Lerista spp.' skinks reported here is an
aggregation of multiple possible species within the L. distinguenda
group (including L. distinguenda, L. elegans and L. microtis), and
'Morethia spp.' skinks is an aggregation of M. obscura and
possibly some M. linocellata specimens. This is a conservative taxonomic
approach, given that of the vouchered specimens, all Lerista were
confirmed by the WA Museum as L. distinguenda and all Morethia were
confirmed as M. obscura, but some unvouchered field identifications
recorded L. elegans, L. microtis and M. linocellata.
Terrestrial vertebrate responses were analysed according to
silvicultural treatment: (1) gap release, (2) shelterwood and (3)
external reference forest. Preliminary analyses also indicated
significant differences between shelterwood and selective cut grids, and
between coupe buffer and external reference grids. These findings were
consistent with an earlier study in the JS ecosystem (Burrows et al.
1994) which indicated that vertebrate fauna respond differently within
the coupe buffers to either silviculturally treated or contemporarily
unharvested forest (Morris et al. 2001; Wayne unpublished data). While
it may be appropriate to include coupe buffer grids as part of the
reference treatment for sedentary or non-volant taxa (McCaw et al. 2011
and individual FORESTCHECK papers within this issue) this is not
appropriate for terrestrial vertebrates. Within the remaining 41
FORESTCHECK monitoring grids upon which this analysis was based, there
was some bias in the replication across ecosystems/regions in the
shelterwood treatment (Table 1) that has been considered when analysing
the data and interpreting the results.
Whether the grids were located in forest areas subject to routine
aerial fox control as part of the Western Shield program (Armstrong
2004; Orell 2004) was not considered at the time of site selection but
is indicated in Table 1. Shelterwood, gap release and external reference
treatments are not confounded with fox control, with about half the
grids in each being subject to regular fox baiting. However, within each
of the external reference subsets there is confounding: six of the eight
never-harvested grids and two of the seven previously harvested
reference grids were not subject to fox control. There was also
confounding within some ecosystems with respect to fox control (JNW-C,
JNW-N and JB) and between ecosystems over time (i.e. one ecosystem
sampled per year) (Table 1). The analyses and interpretation of the
results from this study has, therefore, given due regard to these
Analysis followed the standard protocol used for all biota groups
examined in FORESTCHECK (see 'Data analysis', McCaw et al.
2011) and is summarised here. Species accumulation curves were
determined for each treatment and for the total sampling effort over the
five sample years using Estimates software (Colwell 2005). Estimates of
total species richness were calculated using statistical extrapolation
and the first-order jackknife estimator (JACK1) (Heltsche and Forrester
Differences in terrestrial vertebrate communities between
treatments were examined using four complementary approaches.
Dominance--diversity curves were constructed to give a visual
representation of population abundance structure in each treatment. Two
multivariate procedures, non-metric multidimensional scaling (nMDS)
(Kruskal 1964) and canonical analysis of principal coordinates (CAP)
(Anderson and Robinson 2003), were used to examine differences in
species assemblages between treatments and forest ecosystems, and
overall differences in species assemblages between treatments and
ecosystems were tested using permutation multivariate analysis of
variance (PerMANOVA) (Anderson 2001). All nMDS, CAP and PerMANOVA
analyses used PRIMER software (Clarke and Gorley 2006).
Multivariate linear modelling was used to assess the effects of
silvicultural treatment, ecosystem/year, live standing tree basal area,
years since harvested, years since last burnt, and fox control on
vertebrate abundance and species richness, using the GLM procedure in
the SAS software (SAS Institute Inc. 2004). Live standing basal area and
years since last burnt were continuous covariates, whereas all other
effects were categorical; years since harvested was coded into four
categories (0-4 y, 5-9 y, 10 y or more, or never harvested); and fox
control as binary yes/no. Initially, a model including all main effects
was fitted using the model-building strategy of Hosmer and Lemeshow
(2000). Because the sample size was relatively small, any clearly
non-significant effects (P > 0.15) other than treatment (the main
variable of interest) were sequentially excluded from the main-effects
model and the remaining effects re-evaluated. Once final models
containing only the significant main effects and treatment were
obtained, single degree-of-freedom contrasts were used to test specific
a priori hypotheses of interest and the means and standard errors for
each effect calculated, after adjusting for other effects. Examination
of residuals was used to assess the assumptions of normality and
constant variance using standard methods (Zuur et al. 2010), and
abundance data were log-transformed to meet these assumptions. Sample
size was insufficient to permit examination of interactions between
Detectable effect sizes for species richness and abundance were
determined using standard methods, based on the results of analysis of
variance (ANOVA) (Osenberg et al. 1994).
Forty-one terrestrial vertebrate taxa (8 frogs, 22 reptiles, 11
mammals) were recorded from pitfall and wire cage traps (Table 2). Four
taxa constituted 55% of all capture records (n = 1165): the mammal T.
vulpecula (22%), Lerista spp. (14%) and Morethia spp. (11%) skinks, and
the mammal B. penicillata (8%). Eight species were recorded only once
(i.e. singletons); seven from the coupe buffer and external reference
grids (1, 3 and 3 species respectively at a coupe buffer, an external
reference grid harvested more than 40 y ago and a never-harvested
external reference grid) and one, the snake Notechis scutatus, from a
shelterwood grid. Except for the eight singletons and the frog
Pseudophryne guentheri (two records), no species was detected
exclusively within one treatment (Table 2). Eight of the 10 species
recorded from only one ecosystem/year were from either JS (2001-02) or
JB (2005-06). Another 10 species were recorded from two
ecosystems/years, four species from three, 10 species from four and only
seven species were recorded in all five ecosystems/ years.
Several species were detected in all but one treatment (Table 2);
the frog Heleioporus eyrei was not detected in an external reference
grid (n = 15), the snake Ramphotyphlops australis was not detected in a
coupe buffer grid (n = 4) and the frogs Crinia georgiana and
Limnodynastes dorsalis, the reptiles Acritoscincus trilineatum, Menetia
greyii and Pogona minor, and the mammals B. penicillata and D. geoffroii
were not detected in a selective cut grid (n = 3).
The mean abundance of the reptile Egernia napoleonis was greater on
the shelterwood grids relative to external reference and gap release
treatments (P < 0.01 and P < 0.02, respectively). Similarly, R.
australis was more abundant in the shelterwood treatment relative to
external reference treatment (P = 0.01). There were no other significant
pairwise differences in the mean abundance of terrestrial vertebrate
species between the two main silvicultural treatments (shelterwood, gap
release) and external reference forest.
Species accumulation curves
Rates of species accumulation were similar for gap release,
shelterwood and external reference grids (Fig. 1), but there was a trend
for the harvested treatments (shelterwood and gap release) to initially
increase more rapidly but have slightly fewer species at 300 individuals
compared to the external reference treatment. Thirty-four species were
detected at the 15 external reference grids, 32 species at the 14 gap
release grids and 29 species at the 12 shelterwood grids. At n = 12
grids, the modelled species richness was 31 for both external reference
and gap release treatments.
The number of species increased relative to the number of captured
individuals marginally more rapidly in the external reference treatment
compared with those subjected to harvesting, particularly the
shelterwood treatment (Fig. 2). Species accumulation rates for each
treatment did not approach asymptotes within the range of individuals
sampled (286-375 individuals each treatment), although when all grids
were combined (i.e. increased sample size) the species accumulation
curve approached an approximate asymptote when more than 750 individuals
Dominance--diversity curves were similar for gap release,
shelterwood and external reference treatments (Fig. 3). The same three
species were the most common in all treatments but their rankings
varied. Within the external reference treatment, the mammal T. vulpecula
and the skinks Lerista spp. and Morethia spp. were the three most common
species respectively. Within the shelterwood treatment the descending
ranking was Lerista spp., T. vulpecula and Morethia spp. Within the gap
release treatment, Lerista spp. and Morethia spp. were equally the most
abundant, followed by T. vulpecula. The relative dominance of the most
abundant species was greatest in the external reference treatment (T.
vulpecula was roughly twice as abundant as the next most common species)
and least in the gap release (the abundances of the three most common
species were roughly equal) (Fig. 3). The proportion of species recorded
only once or twice was 34% for both shelterwood and gap release
treatments and 47% in the external reference treatment.
[FIGURE 1 OMITTED]
[FIGURE 2 OMITTED]
Species richness and abundance
Multivariate linear modelling was used to assess the effects of
silvicultural treatment, ecosystem/year, live tree basal area, years
since harvested, years since last burnt, and fox control on vertebrate
abundance and species richness. Fox control (P < 0.01), time since
harvest (P < 0.01) and ecosystem/year (P = 0.02) significantly
affected abundance but silvicultural treatment did not (P = 0.26),
whereas only silvicultural treatment affected species richness (P =
0.03). Live basal area and years since last burnt did not affect
abundance (P = 0.19 and P = 0.46, respectively) or richness (P = 0.27
and P = 0.56, respectively).
The means for each of these effects were compared using single-df
contrasts. Fox-baited sites had significantly higher abundance (33 vs 10
individuals, P < 0.01) and slightly higher richness (9 vs 7 species,
P = 0.17). The sites that had never been harvested had the lowest
abundance (11), less than the 18 for 1-4 y, and significantly less than
the 23 and 26 for 5-9 or 10+ years since harvest, respectively. Although
abundance varied significantly between ecosystem/years (range 11-35),
there was no difference between silvicultural treatments (Tables 3, 4).
A combined comparison of harvested treatments with external reference
forest also showed no significant difference (P = 0.78). Richness,
however, was significantly lower in external reference grids (by 30%;
[FIGURE 3 OMITTED]
Compared with areas baited for foxes (n = 21 grids), unbaited grids
(n = 20) had, on average, substantially fewer koomals (T vulpecula)
(mean 8.57 vs 0.10, respectively; P < 0.01), Tiliqua rugosa skinks
(mean 0.52 vs 0.05, respectively; P = 0.01), and woylies (B.
penicillata) (mean 3.90 vs 0.15, respectively; P = 0.03), and marginally
fewer pygmy possums (Cercartetus concinnus) (mean 0.66 vs 0.05,
respectively; P = 0.05), and chuditches (D. geoffroii) (mean 0.62 vs
0.15, respectively; P = 0.06).
Never-harvested grids were confounded with fox baiting history (6/8
grids were not fox-baited) and predominantly located in the JNW-C and
JNE ecosystems. The most common taxa recorded were either not detected
at the never-harvested grids (T. vulpecula and B. penicillata) or much
less frequently so than at other grids (Lerista spp. and H. peroni
Modelling (PerMANOVA) of community structure involving
silvicultural treatments, the five ecosystems/years and the interaction
term between these two factors revealed no significant relationship for
the interactive term (P = 0.58), a significant difference in community
structure according to ecosystem/ year (P < 0.01), but no overall
significant difference between silvicultural treatments (P = 0.08).
Nonetheless, a priori pair-wise comparisons of community structure
between treatments revealed a significant difference between external
reference forest and shelterwood (P = 0.01) (Table 4). The two pair-wise
comparisons with gap release were not significant (P = 0.30 and P = 0.49
for shelterwood and external reference treatments, respectively).
The nMDS ordination of community structure did not discriminate
silvicultural treatments (two-dimension stress = 0.22) (Fig. 4). The CAP
ordination also showed no clear separation between the silvicultural
treatments (P = 0.22) (Fig. 5), but, consistent with the perMANOVA,
shelterwood and external reference treatments did tend to differentiate
to some extent along axis one. To determine which species were
associated with silvicultural treatment, correlations between abundances
and the axis scores were calculated. The reptiles E. napoleonis, M.
greyii, Ctenotus labillardieri and to a lesser extent R. australis were
more prevalent or abundant on harvested grids (i.e. their abundances
were significantly and negatively correlated with axis 1). No taxa were
positively associated with external reference forest.
Consistent with the PerMANOVA analysis, the CAP ordination of
community structure revealed highly significant differences between
ecosystem/year of sampling (P = 0.0001) (Fig. 6). The ordination clearly
distinguished and grouped grids within the same ecosystem/year and
generally reflected the geographic/ bioclimatic relationship between
grids (axis one and two approximate the north--south and west--east
geographic spread of grids, respectively). Communities at the two
locations in the JNW ecosystem were not readily distinguished from each
other. The prevalence and abundance of the reptile Hemiergis peroni and
koomals (T. vulpecula) were most strongly associated with grids towards
the left-hand side of axis one (i.e. southern grids) and Lerista spp.and
M. greyi skinks were more strongly associated with grids toward the
right-hand side of axis one (i.e. had correlations greater than 0.58 or
less than -0.58). Key taxa discriminating grids on axis two were the
woylie (B. penicillata) (more prevalent at grids toward the bottom of
the graph) and the skink C. labillardieri (more prevalent at grids
toward the top of the graph) (i.e. had correlations greater than 0.40 or
less than -0.40).
[FIGURE 4 OMITTED]
[FIGURE 5 OMITTED]
[FIGURE 6 OMITTED]
Terrestrial vertebrates in relation to standing tree basal area
Plots revealed no clear relationship between live tree basal area
and either species richness or total terrestrial vertebrate abundance,
consistent with the multivariate modelling described above. There was
also no significant relationship between community structure and live
standing tree basal area (PerMANOVA, P = 0.09, n = 41 grids) after
accounting for the significant ecosystem/year factor (P < 0.01) and
its interaction with the basal area covariate (P = 0.40). Similarly
there was no significant relationship between community structure and
the proportion of basal area removed during the silvicultural treatment
(PerMANOVA, P = 0.37, n = 41 grids) after accounting for the significant
ecosystem/year factor (P < 0.01) and their interaction (P = 0.26).
The detectable effect size (with 95% confidence) (Osenberg et al.
1994) for the current Forestcheck terrestrial vertebrate monitoring
design and data (41 grids, 3 treatments, 12-15 grids per treatment) is
23% for species richness and for 37% for abundance. Table 5 provides
estimates of the number of monitoring grids required to achieve various
detectable effect sizes.
Silvicultural treatment differences
Several terrestrial vertebrate community attributes were similar in
silvicultural treatments and reference forests, including species
accumulations by grids and number of individuals, dominance--diversity
plots, overall community structure and overall abundance. External
reference grids, however, had significantly lower species richness than
shelterwood grids and a significantly different community structure.
These differences resulted from a greater prevalence within shelterwood
of some species such as the reptiles Egernia napoleonis, Morethia
greyii, Ctenotus labillardieri and Ramphotyphlops australis. These
likely benefit from the larger amounts of coarse woody debris in
harvested grids (McCaw 2011) and the intermediate state of forest
structure and diversity available in shelterwoods (e.g. moderately open
forest structure; increased ectothermic opportunities such as basking
sites and the nature, diversity and distribution of micro habitats).
Egernia napoleonis shelters in and forages from the crevices of larger
logs (Bush et al. 1995; pers. obs.), the abundance of which is likely to
be a key factor in determining skink densities (Craig et al. 2011).
Although C. labillardieri is predominantly a rock-dwelling species it
also shelters under logs and bark (Cogger 1994). A subterranean
specialist, the distribution and abundance of R. australis is associated
with soil and invertebrate prey, particularly ants and termites (Ehmann
and Bamford 1993; Cogger 1994) that may be associated with coarse woody
debris. Soil disturbance used to promote jarrah seedling establishment
in shelterwoods may also benefit R. australis. Morethia greyi is a
widespread habitat generalist found in a range of environments from dry
sclerophyll forest to arid scrub (Cogger 1994) and can be found in
disturbed sites, including suburban backyards (Bush et al. 1995).
The most abundant terrestrial mammals recorded in this study were
Trichosurus vulpecula and Bettongia penicillata. Neither species
displayed a strong response to silvicultural treatment. In comparable
areas of jarrah forest, B. penicillata abundance was similar in
harvested forest and external reference grids but T. vulpecula decreased
significantly immediately (less than 2 y) after shelterwood treatment,
in gap releases where retained habitat trees were experimentally removed
and in adjacent unharvested buffers (Morris et al. 2001). Because of the
replicated BACI (before--after, control--impact) design of the Morris et
al. (2001) study, the results are likely to be sensitive and reflect the
true short-term responses of these mammals (e.g. Underwood et al. 1996;
Kavanagh and Stanton 2005). Since this study found no detectable effects
on T. vulpecula at sites silviculturally treated more than 2 y
previously, it appears that any effects may be transitory.
For frogs, both generally and with this study, difficulties with
sampling and highly variable measures of abundance over space (e.g.
Goldingay et al. 1996) and time (e.g. diurnal to annual variation due to
weather, season, etc.; deMaynadier and Hunter 1995) have resulted in
there being insufficient information to understand their responses to
silvicultural treatment (e.g. Kavanagh and Webb 1998).
In this study, lower vertebrate abundances on never-harvested grids
largely reflected the absence of otherwise common mammals T. vulpecula
and B. penicillata, and lower abundances of otherwise common reptiles.
These differences are best explained by the confounding of the
never-harvested external reference treatment with fox control (6/8 grids
not fox-baited). Also, most of the never-harvested grids were located in
the JNW-C and JNE ecosystems, which accounts for the lower abundance of
common reptiles such as the skinks, Hemiergisperoni (more prevalent in
JS ecosystem) and Lerista spp. (more prevalent in JNW ecosystem). While
there is confounding within the external reference treatment subsets,
differences between gap release and shelterwood silvicultural treatments
and the external reference treatment have been analysed with fox control
as a covariate, enabling treatment effects to be examined independently.
Kavanagh and Stanton (2005) reported the response of 227 vertebrate
species (including bats and birds) to selective timber harvesting at 487
sites across north-eastern New South Wales (NSW). In frequency of
occurrence, 18% were significantly disadvantaged, 18% were favoured and
65% were apparently unaffected, but for many there were insufficient
data to assess their response (Kavanagh and Stanton 2005). Also, more
species were less common in selectively harvested forest compared with
both unharvested and intensively harvested forests, and more mammal
species were disadvantaged than favoured by harvesting (11 versus 4
species, respectively). Reptiles comprised the largest proportion (39%)
of species sensitive to harvesting, with many species responding
differently according to the intensity of harvesting. No species
displayed consistently strong preferences for selectively harvested
forest. Their findings contrast with our study, which found higher mean
species richness and overall abundances in shelterwood (a treatment of
moderate intensity), and two reptiles (E. napoleonis and R. australis)
were more abundant in shelterwood compared with the external reference
treatment: the only significant pair-wise differences.
In this study, fox control had the strongest effect on terrestrial
vertebrate abundance. Areas regularly aerially baited (Armstrong 2004;
Wyre 2004) supported significantly more individuals (three-fold
increase) and around 20% more species than unbaited areas, although this
latter effect is not statistically significant. Several
conservation-listed medium-sized mammals (T. vulpecula, B. penicillata
and Dasyuris geoffroii), the western pygmy possum (Cercartetus
concinnus) and at least one large lizard (Tiliqua rugosa) were
particularly more abundant in fox-baited forest. This finding is
consistent with other studies that indicate foxes and fox control
influence the conservation status, distribution and abundance of many
species, including T. vulpecula, B. penicillata and D. geoffroii (e.g.
How and Hillcox 2000; Burrows and Christensen 2002; Morris et al. 2003;
Orell 2004; Wheeler and Priddel 2009). At less than 20 g adult weight,
the increased abundance of C. concinnus is particularly interesting
given that it is below the so called 'critical weight range'
(35-5500 g) (Burbidge and McKenzie 1989; Kinnear et al. 2002, 2010;
Johnson and Isaac 2009). The current distribution and abundance of some
species is also likely to be an historical artefact of past and present
declines and the managed recoveries of these species. For example, the
current distribution of B. penicillata is a consequence of range
contraction within the jarrah forest to all but one area east of
Manjimup by the 1970s (Start et al. 1998) and subsequent successful
translocations or reintroductions (Mawson 2004).
There were considerable differences in terrestrial vertebrate
species composition, abundance and community structure between the
ecosystems/years. Half of the species (20/41) were recorded from only
one or two ecosystems/years, and only 17% were common to all five
ecosystems/years. Notably, JNW-C (2002-03) and JS (2001-02) had
significantly higher abundances and, while there was no overall
significant difference in species richness, JNW-C (2002-03) had
significantly more species than JNE (2004-05). Community structure
distinctions between ecosystem/years, particularly southern jarrah
(JS/2001-02 and JB/2005-06) from the northern communities, appear to be
strongly influenced by geographically related factors (e.g. climate,
soils and nutrients; see McCaw et al. 2011). However, temporal
influences also need to be considered. For instance, the abundance of B.
penicillata has declined in all large populations in jarrah forest by
more than 90%, including within the JS (2001-02) and JNE (2004-05)
ecosystems, within the 5-y time frame of this study. The species was
recently listed as Critically Endangered (Groom 2010).
Similar overall mean species richness, composition, abundance and
community structure of terrestrial vertebrates in JNW-C (2002-03) and
JNW-N (2003-04) support the classification of these two areas as one
ecosystem, despite its comparatively large north--south extent. This was
also the case for the understorey vascular flora communities of JNW-C,
JNW-N and JNE (Ward et al. 2011) but were markedly distinct for other
taxa including cryptograms (Cranfield et al. 2011), epigeous macrofungi
(Robinson and Williams 2011), invertebrates (Farr et al. 2011) and birds
(Abbott et al. 2011).
Design and data considerations
Detection error, which leads to biased estimates of abundance, is
considered one of the two main sources of variation in monitoring data
(Yoccoz et al. 2001). The assumption that probability of detection is
constant over space and time is common to many field studies that use
indices, such as raw count data, as measures of abundance. Although this
assumption is often invalid (Pollock et al. 2002), there is some
evidence that it may be valid for at least some taxa in this study. For
example, Craig et al. (2009) demonstrated that count data from pitfall
traps accurately reflected total reptile density as well as that of some
individual species, including H. initialis and Lerista spp. (which were
also common in the FORESTCHECK study), and provided relative measures of
abundances that were not influenced by the vegetation structure of
either restored mine pits or unmined jarrah forest. In the southern
jarrah forest, capture probabilities for the mammals T. vulpecula and B.
penicillata, based on mark-recapture modelling from a much larger
dataset, were generally similar or constant over space and time across
different silvicultural treatments (Wayne unpublished data).
Nonetheless, future work associated with FORESTCHECK should test the
veracity of this assumption.
Strengths of the FORESTCHECK study include standard sampling
efforts, continuity of field expertise, and stratified and replicated
trapping sites. All help to reduce detection error and spatial
variation, the second major source of variation in monitoring data
(Yoccoz et al. 2001), and increase confidence in subsequent inferences
from analysis. Nonetheless, few treatment or other effects were detected
in our study (e.g. time since last fire, live tree basal area or the
proportion of basal area removed relative to pre-silvicultural treatment
levels). This may reflect real lack of treatment effects on terrestrial
vertebrates, but may also be due to limitations of our data, including
insufficient records for many species, no records for others known to
occur in jarrah forest, and the limited inferential power available with
the existing data.
Within the treatments, 34-17% of all species were recorded only
once or twice. The reason that eight of the nine species recorded in a
single treatment were from reference forest is likely to be a function
of chance and insufficient sampling rather than them actually being
absent from harvested forest. In a complementary study in the southern
jarrah forest (Wayne et al. 2001; A. Wayne unpublished data), six of
these same eight species were recorded in harvested forest; but that
study was outside the geographic range of the reptiles H. quadrilleata
and L. burtonis. The sampling effort of Wayne et al. (2001) was 3.5
times more than in this study.
Low abundance data for many individual species also made it
difficult to investigate species-level responses to silvicultural
treatments and forest ecosystems. For example, only three species had
more than 100 records across all grids (i.e. an average of more than two
individuals per grid). At least 3 0 native species known to occur in the
areas sampled were not detected in this study, although some of these
(e.g. large macropods) are unlikely to be captured in wire cages or
pitfalls. Evidence for incomplete species detection also includes the
lack of an asymptote in species accumulation curves within treatments,
and the four FORESTCHECK grids located within the Wayne et al. (2001)
study area recorded less than half of the same species (using identical
As a result, statistical power was only sufficient to detect
differences in species richness and abundance between treatments that
were greater than 23% and 37%, respectively. Relative to other taxa the
effort required to generate these data was large. However, FORESTCHECK
is a long-term project and ongoing repeated sampling of grids will mean
that data quality will improve and statistical power will increase over
Learning opportunities for this and other studies of fauna
Ecological monitoring programs for conservation or management are
often considered inadequate (e.g. Yoccoz et al. 2001; Bennett and Adams
2004; Legg and Nagy 2006; Field et al. 2007). Common weaknesses include
poorly defined objectives, insufficient hypothesis formulation, survey
design, data quality and statistical power. Statistical power was a key
limitation of terrestrial vertebrate data in this study, but it can be
improved by changes that reduce residual variance and increase sample
size (Legg and Nagy 2006).
Increasing the number of replicates within a well-balanced
stratified design, with well-defined selection criteria to eliminate
extraneous sources of variation, will increase statistical power and
thus enable the use of simple and more powerful statistical models and
parametric tests (e.g. Legg and Nagy 2006). The importance of design
considerations including all major effects, and not just those of
principal interest, is highlighted by the confounding of fox control
within external reference subsets and between ecosystem/ years in this
study. The consideration of JNW-C and JNW-N grids as replicates within
the one JNW ecosystem category would also be appropriate to improve
efficiency, given the similarities of these locations. Confounding
between ecosystem and year could be overcome by surveying all or a
subset of the treatments (e.g. external reference) within the same year.
However, subsequent rounds of monitoring will also aid in clarifying
ecosystem differences and improve statistical power, through aggregation
of data from multiple years.
Increased sample effort at the grid level is also important. As
well as improving abundance data, more frequent sampling within a given
year will increase the likelihood of detecting more species. This is
especially so for herpetofauna, that are active for relatively limited
periods and or have peak activity periods that vary between species
according to seasons (e.g. Main 1965) and particular meteorological
factors (e.g. Lemckert 2001; Penman et al. 2006). The timing of surveys
in relation to seasonal differences in abundance may also be important
for some species, such as Phascogale sp. with an annual male die-off
that can result in at least a 50% variation in population abundance
within an annual cycle (Rhind 2002). The use of additional complementary
survey methods would enhance the dataset, and records from spotlighting,
sand pads, and sighting surveys from vehicles conducted as part of
Forestcheck could also be incorporated into future analyses.
Species-specific monitoring and research may also be necessary and
particularly valuable for priority taxa that are more readily detected
by more specific methods such as nest boxes for Phascogale sp. and scat
surveys for the possum Pseudocheirus occidentalis (Wayne et al. 2005b).
Other analytical approaches may also help (e.g. improved control of
covariates and Bayesian and information theoretic approaches). More
reliable measures of abundance may be possible using mark-recapture
methods (e.g. Pollock et al. 1990) or by developing better estimates of
detection probability by other means, such as using the double sampling
approach (Pollock et al. 2002).
The completion of the second cycle of monitoring will provide an
increased dataset to investigate vertebrate associations and enable
preliminary estimations of how repeated sampling over time is likely to
improve statistical power (Field et al. 2007). The integrated nature of
Forestcheck also allows more detailed investigations of relationships
across major taxonomic groups and other forest attributes (such as
soils, nutrients and coarse woody debris) that should provide a better
understanding of the ecology of jarrah forest.
It is important that monitoring programs are associated with
experimental work (Legg and Nagy 2006; Nichols and Williams 2006 and
references within). Experimental research is especially valuable in
verifying the causes and identifying the reasons for observed changes or
differences (i.e. the processes behind responses). Forestcheck is
directly complemented by experimental work investigating the effects of
silviculture within the southern jarrah forest (Burrows et al. 1994,
2001; Morris et al. 2001; Abbott et al. 2003a,b; Craig and Roberts
2005). Future investigations should include a more direct integration
and synthesis between these programs as well as developing similar
research studies in other locations and or regarding other major factors
in common with Forestcheck. However, tension remains between the value
of making any of these improvements and the feasibility of being able to
do so with available resources.
It is important to also emphasise that only the most common and
widespread species furnish sufficient data for rigorous statistical
analysis (Kavanagh and Stanton 2005). Rare, patchy and potentially
sensitive or specialist species may be too difficult to directly measure
their responses to disturbance. Alternative approaches are therefore
necessary, such as the investigation of community-level responses (as in
this study), the aggregation of taxa according to ecological guilds or
by some other biologically meaningful criterion, the possible use of
surrogates and indicator species, use of ecological first principles and
other less direct or lateral means, such as comparative life history
studies (Lauck 2005). Nonetheless, management necessarily continues
within the context of incomplete and imperfect information. Therefore,
while specific information may be necessary, complete knowledge is not
essential to ensure sustainable forest management. Continued application
of the precautionary principle (e.g. Deville and Harding 1997) and
active adaptive management (Walters and Holling 1990; Lee 1999) can
progressively improve knowledge and management.
Summary of responses
The greatest sources of variation in terrestrial vertebrate
richness, abundance and community structure in this study were the
beneficial effect of fox control on those species subject to fox
predation, and differences attributable to ecosystem/year effects. In
comparison, silvicultural treatment and the intensity of timber
harvesting had minor effects. Some species were not recorded from
particular treatments but this may simply reflect non-detection rather
than true absence. Similarly, there was no relationship between live
tree basal area after timber harvesting and either species richness or
total abundance. Significant associations between terrestrial
vertebrates and silvicultural treatment were nonetheless evident. The
significantly different community structure between shelterwood grids
and external reference forest was largely reflected in the former having
higher mean species richness, two reptiles being more abundant, and
greater overall vertebrate abundance. Within the limits of the data, no
species were negatively associated with silvicultural treatment compared
with external reference forest. Indeed, the fraction of species
apparently unaffected by harvesting was much higher than reported by
comparable studies in eastern Australia. Therefore it is likely that the
current silvicultural treatments in the jarrah forest have been within
the tolerance thresholds to disturbance for many of the terrestrial
vertebrates as suggested for other taxa in these forests (e.g. Abbott et
We thank the animal handlers who collected data in the field (Bruce
Ward, Colin Ward, Chris Vellios, Marika Maxwell and Christina Gilbert);
Nature Conservation Program Leaders and employees at Donnelly,
Wellington, Perth Hills and Blackwood Districts of the Department of
Environment and Conservation for essential assistance and support of
field activities (including Ian Wilson, Jennifer Langton, Drew
Griffiths, Steve Gunn, Steve Thomas, Frank Collier and Kelly Bennett);
Verna Tunsell for database management; Amanda Mellican for preliminary
analyses of some of the data; and Richard Robinson, Lachie McCaw and Ian
Abbott for comments on drafts of this manuscript. Thank you also to the
referees who helped to improve this paper.
Abbott, I. and Burrows, N. (2004) Monitoring biodiversity in jarrah
forest in south-west Western Australia: the FORESTCHECK initiative. In:
Lunney, D. (ed.) Conservation of Australia's Forest Fauna. 2nd edn.
Royal Zoological Society of New South Wales, Mosman, NSW, Australia, pp.
Abbott, I. and Whitford, K. (2002) Conservation of vertebrate fauna
using hollows in forests of south-west Western Australia: strategic risk
assessment in relation to ecology, policy, planning, and operations
management. Pacific Conservation Biology 7, 240-255.
Abbott, I., Burbidge, T., Strehlow, K., Mellican, A. and Wills, A.
(2003a) Logging and burning impacts on cockroaches, crickets and
grasshoppers, and spiders in jarrah forest, Western Australia. Forest
Ecology and Management 174, 383-399.
Abbott, I., Mellican, A., Craig, M.D., Williams, M., Liddelow, G.
and Wheeler, I. (2003b) Short-term logging and burning impacts on
species richness, abundance and community structure of birds in open
eucalypt forest in Western Australia. Wildlife Research 30, 321-329.
Abbott, I., Liddelow, G. L.,Vellios, C.V., Mellican, A.E. and
Williams, M.R. (2011) FORESTCHECK : the response of birds to
silviculture in jarrah (Eucalyptus marginata) forest. Australian
Forestry 74, 328-335.
Adams, M.D., Law, B.S. and French, K.O. (2009) Vegetation structure
influences the vertical stratification of open- and edge-space
aerial-foraging bats in harvested forests. Forest Ecology and Management
Alexander, J.S.A., Scotts, D.J. and Loyn, R.H. (2002) Impacts of
timber harvesting on mammals, reptiles and nocturnal birds in native
hardwood forests of East Gippsland, Victoria: a retrospective approach.
Australian Forestry 65, 182-210.
Anderson, M.J. (2001) A new method for non-parametric multivariate
analysis of variance. Austral Ecology 26, 32-46.
Anderson, M.J. and Robinson, J. (2003) Generalized discriminant
analysis based on distances. Australian and New Zealand Journal of
Statistics 45, 301-318.
Armstrong, R. (2004) Baiting operations: Western Shield
review--February 2003. Conservation Science WA 5, 31-50.
Baker, S. and Lauck, B. (2006) Association of common brown
froglets, Crinia signifera, with clearcut forest edges in Tasmania,
Australia. Wildlife Research 33, 29-34.
Barry, S.J. (1984) Small mammals in a south-east Queensland
rainforest: the effects of soil fertility and past logging disturbance.
Australian Wildlife Research 11, 31-39.
Bennett, L.T. and Adams, M.A. (2004) Assessment of ecological
effects due to forest harvesting: approaches and statistical issues.
Journal of Applied Ecology 41, 585-598.
Burbidge, A.A. and McKenzie, N.L. (1989) Patterns in the modern
decline of Western Australia's vertebrate fauna: causes and
conservation implications. Biological Conservation 50, 143-198.
Burrows, N.D. and Christensen, P.E.S. (2002) Long-term trends in
native mammal capture rates in a jarrah forest in south-western
Australia. Australian Forestry 65, 211-219.
Burrows, N., Friend, G., Morris, K., Stoneman, G., Craig, M. and
Williams, M. (1994) An Integrated Study of the Effects of Timber
Harvesting on the Jarrah Forest Ecosystem. Department of Conservation
and Land Management, Perth, Western Australia.
Burrows, N.D., Ward, B. and Cranfield, R. (2001) Short-term impacts
of logging on understory vegetation in a jarrah forest. Australian
Forestry 65, 47-58.
Bush, B., Maryan, B., Browne-Cooper, R. and Robinson, D. (1995) A
Guide to the Reptiles and Frogs of the Perth Region. University of
Western Australia Press.
Calver, M.C. and Dell, J. (1998a) Conservation status of mammals
and birds in southwestern Australian forests. I. Is there evidence of
direct links between forestry practices and species decline and
extinction? Pacific Conservation Biology 4, 296-314.
Calver, M.C. and Dell, J. (1998b) Conservation status of mammals
and birds in southwestern Australian forests. II. Are there unstudied,
indirect or long-term links between forestry practices and species
decline and extinction? Pacific Conservation Biology 4, 315-325.
Calver, M.C. and Wardell-Johnson, G. (2004) Sustained
unsustainability? An evaluation of evidence for a history of overcutting
in the jarrah forests of Western Australia and its consequences for
fauna conservation. In: Lunney, D. (ed.) Conservation of
Australia's Forest Fauna. Royal Zoological Society of New South
Wales, Sydney, pp. 94-114.
Christensen, P.E.S. (1997) A Review of the Knowledge of the Effects
of Key Disturbances on Fauna in the South-West Forest Region. Western
Australian Government Department of Conservation of Land Management,
Christensen, P.E.S. and Abbott, I. (1989) Impact of fire in the
eucalypt forest ecosystem of southern Western Australia: a critical
review. Australian Forestry 52, 103-121.
Clarke, K.R. and Gorley, R.N. (2006) PRIMER v6: User
Manual/Tutorial. PRIMER-E, Plymouth.
Cogger, H.G. (1994) Reptiles and Amphibians of Australia. Reed
Books, Chatswood NSW.
Colwell, R.K. (2005) EstimateS: Statistical estimation of species
richness and shared species from samples. Version 7.5. User's
Guide. http:// purl.oclc.org/estimates.
Craig, M.D. and Roberts, J.D. (2005) The short-term impacts of
logging on the jarrah forest avifauna in south-west Western Australia:
implications for the design and analysis of logging experiments.
Biological Conservation 124, 177-188.
Craig, M.D., Grigg, A.H., Garkaklis, M.J., Hobbs, R.J., Grant,
C.D., Flemming, P.A. and Hardy, G.E.S. (2009) Does habitat structure
influence capture probabilities? A study of reptiles in a eucalypt
forest. Wildlife Research 36, 509-515.
Craig, M.D., Benkovic, A.M., Grigg, A.H., Hardy, G.E.S., Fleming,
P.A. and Hobbs, R.J. (2011) How many mature microhabitats does a
slow-recolonising reptile require? Implications for restoration of
bauxite minesites in south-western Australia. Australian Journal of
Zoology 59, 9-17.
Cranfield, R.J., Robinson, R.M., Williams, M.R. and Tunsell, V.L.
(2011) Forestcheck : the response of lichens and bryophytes to
silviculture in jarrah (Eucalyptus marginata) forest. Australian
Forestry 74, 303-314.
deMaynadier, P.G. and Hunter Jr., M.L. (1995) The relationship
between forest management and amphibian ecology: a review of the North
American literature. Environmental Reviews 3, 230-261.
Deville, A. and Harding, R. (1997) Applying the Precautionary
Principle. Federation Press, Sydney.
Ehmann, H. and Bamford, M.J. (1993) Family Typhlopidae. In: Glasby
C.J., Ross, G.J.B. and Beesley, P.L. (eds) Fauna of Australia. Vol 2A.
Amphibia and Reptilia. Australian Government Publishing Service,
Canberra, pp. 280-283.
Farr, J.D., Wills, A.J., Van Heurck, P.F., Mellican, A.E. and
Williams, M.R. (2011) Forestcheck : the response of macro-invertebrates
to silviculture in jarrah (Eucalyptus marginata) forest. Australian
Forestry 74, 315-327.
Faunt, K. (1992) Formation, Frequency and Longevity of Hollows in
Jarrah. Western Australian Government Department of Conservation and
Land Management, Perth.
Field, S.A., O'Connor, P.J., Tyre, A.J. and Possingham, H.P.
(2007) Making monitoring meaningful. Austral Ecology 32, 485-491.
Friend, J.A. (1994) Recovery Plan for the Numbat (Myrmecobius
fasciatus) 1995-2004. Western Australian Wildlife Management Program No.
18. Department of Conservation and Land Management, Western Australia.
Friend, G.R. and Wayne, A.F. (2003) Relationships between mammals
and fire in south-west Western Australian ecosystems: what we know and
what we need to know. In: Abbott, I. and Burrows, N.D. (eds) Fire in
Ecosystems of South-West Western Australia: Impacts and Management.
Backhuys Publishers, Leiden, The Netherlands, pp. 363-380.
Gibbons, P. and Lindenmayer, D.B. (2002) Tree Hollows and Wildlife
Conservation in Australia. CSIRO Publishing, Melbourne.
Gillespie, G.R. (2002) Impacts of sediment loads, tadpole density,
and food type on the growth and development of tadpoles of the spotted
tree frog Litoria spenceri: an in-stream experiment. Biological
Conservation 106, 141-150.
Goldingay, R.G., Daly, G. and Lemckert, F. (1996) Assessing the
impacts of logging on reptiles and frogs in the montane forests of
southern New South Wales. Wildlife Research 23, 495-510.
Groom, C. (2010) Justification for continued conservation efforts
following the delisting of a threatened species: a case study of the
woylie, Bettongia penicillata ogilbyi (Marsupialia: Potoroidae).
Wildlife Research 37, 183-193.
Hazell, D. (2003) Frog ecology in modified Australian landscapes: a
review. Wildlife Research 30, 193-205.
Heltsche, J.F. and Forrester, N.E. (1983) Estimating species
richness using the jackknife procedure. Biometrics 39, 1-12.
Hosmer, D.W. and Lemeshow, S. (2000) Applied Logistic Regression.
2nd edn. Wiley, New York.
How, R.A. and Hillcox, S.J. (2000) Brushtail possum, Trichosurus
vulpecula, populations in south-western Australia: demography, diet and
conservation status. Wildlife Research 27, 81-89.
Inions, G.B., Tanton, M.T. and Davey, S.M. (1989) Effect of fire on
the availability of hollows in trees used by the common brushtail
possum, Trichosurus vulpecula Kerr, 1792, and the ringtail possum,
Pseudocheirus peregrinus Boddaerts, 1785. Australian Wildlife Research
Johnson, C.N. and Isaac, J.L. (2009) Body mass and extinction risk
in Australian marsupials: the 'critical weight range'
revisited. Austral Ecology 34, 35-40.
Jones, B. (2004) The possum fauna of Western Australia: decline,
persistence and status. In: Goldingay, R.L. and Jackson, S.M. (eds) The
Biology of Australian Possums and Gliders. Surrey Beatty and Sons,
Sydney, pp. 149-160.
Jones, B. and Hillcox, S. (1995) A survey of the possums
Trichosurus vulpecula and Pseudocheirus occidentalis and their habitats
in forest at Ludlow, Western Australia. Western Australian Naturalist
Jones, B.A., How, R.A. and Kitchener, D.J. (1994a) A field study of
Pseudocheirus occidentalis (Marsupialia: Petauridae). I. Distribution
and habitat. Wildlife Research 21, 175-187.
Jones, B.A., How, R.A. and Kitchener, D.J. (1994b) A field study of
Pseudocheirus occidentalis (Marsupialia: Petauridae). II. Population
studies. Wildlife Research 21, 189-201.
Kavanagh, R.P. and Bamkin, K.L. (1995) Distribution of nocturnal
forest birds and mammals in relation to the logging mosaic in
south-eastern New South Wales, Australia. Biological Conservation 71,
Kavanagh, R.P. and Stanton, M.A. (2005) Vertebrate species
assemblages and species sensitivity to logging in the forests of
north-eastern New South Wales. Forest Ecology and Management 209,
Kavanagh, R.P. and Webb, G.A. (1998) Effects of variable-intensity
logging on mammals, reptiles and amphibians at Waratah Creek,
southeastern New South Wales. Pacific Conservation Biology 4, 326-347.
Kinnear, J.E., Sumner, N.R. and Onus, M.L. (2002) The red fox in
Australia--an exotic predator turned biocontrol agent. Biological
Conservation 108, 335-359.
Kinnear, J.E., Krebs, C.J., Pentland, C., Orell, P., Holme, C. and
Karvinen, R. (2010) Predator-baiting experiments for the conservation of
rock-wallabies in Western Australia: a 25-year review with recent
advances. Wildlife Research 37, 57-67.
Kruskal, J.B. (1964) Multidimensional scaling by optimizing
goodness of fit to a nonmetric hypothesis. Psychometrika 29, 1-27.
Lamb, D. and Smyth, A. (2003) Forests. In: Attiwill, P. and Wilson,
B. (eds) Ecology: An Australian Perspective. Oxford University Press,
Melbourne, pp. 331-351.
Lauck, B. (2005). Impact of forestry practices on amphibian life
histories. PhD thesis, University of Tasmania.
Lauck, B. (2006) Fluctuating asymmetry of the frog Crinia signifera
in response to logging. Wildlife Research 33, 313-320.
Laurance, W.F. and Laurance, S.G.W. (1996) Responses of five
arboreal marsupials to recent selective logging in tropical Australia.
Biotropica 28, 310-322.
Lee, K.N. (1999) Appraising adaptive management. Conservation
Ecology 3, 3.
Legg, C.J. and Nagy, L. (2006) Why most conservation monitoring is,
but need not be, a waste of time. Journal of Environmental Management
Lemckert, F. (1999) Impacts of selective logging on frogs in a
forested area of northern New South Wales. Biological Conservation 89,
Lemckert, F.L. (2001) The influence of micrometeorological factors
on the calling activity of the frog Crinia signifera (Anura:
Myobatrachidae). Australian Zoologist 31, 625-631.
Lindenmayer, D.B. (1994) Wildlife corridors and the mitigation of
logging impacts on fauna in wood-production forests in southeastern
Australia--a review. Wildlife Research 21, 323-340.
Lindenmayer, D.B. (2000) Factors at multiple scales affecting
distribution patterns and their implications for animal
conservation--Leadbeater's possum as a case study. Biodiversity and
Conservation 9, 15-35.
Lindenmayer, D.B. and Franklin, J.F. (2002) Conserving Forest
Biodiversity: A Comprehensive Multiscaled Approach. Island Press,
Lindenmayer, D.B. and Hobbs, R.J. (2004) Fauna conservation in
Australian plantation forests--a review. Biological Conservation 119,
Lindenmayer, D.B., Cunningham, R.B. and McCarthy, M.A. (1999) The
conservation of arboreal marsupials in the montane ash forests of the
central highlands of Victoria, south-eastern Australia. VIII. Landscape
analysis of the occurrence of arboreal marsupials. Biological
Conservation 89, 83-92.
Lindenmayer, D.B., Burton, P.J. and Franklin, J.F. (2008) Salvage
Logging and its Ecological Consequences. Island Press, Washington DC.
Lloyd, A., Law, B. and Goldingay, R. (2006) Bat activity on
riparian zones and upper slopes in Australian timber production forests
and the effectiveness of riparian buffers. Biological Conservation 129,
Lunney, D., Eby, P. and O'Connell, M. (1991) Effects of
logging, fire and drought on three species of lizards in Mumbulla State
Forest on the south coast of New South Wales. Australian Journal of
Ecology 16, 33-46.
Lunney, D., Matthews, A., Eby, P. and Penn, A. (2009) The long-term
effects of logging for woodchips on small mammal populations. Wildlife
Research 36, 691-701.
Main, A.R. (1965) Frogs of Southern Western Australia. Western
Australian Naturalist Club, Perth.
Mawson, P.R. (2004) Translocations and fauna reconstruction sites:
Western Shield review--February 2003. Conservation Science WA 5,
McCaw, W.L. (2011) Characteristics of jarrah (Eucalyptus marginata)
forest at Forestcheck monitoring sites in south-west Western Australia:
stand structure, litter, woody debris, soil and foliar nutrients.
Australian Forestry 74, 254-265.
McCaw, W.L., Robinson, R.M. and Williams, M.R. (2011) Integrated
biodiversity monitoring for the jarrah (Eucalyptus marginata) forest in
south-west Western Australia: the Forestcheck project. Australian
Forestry 74, 240-253.
Morris, K., Johnson, B., Rooney, J. and Ward, C. (2001) The
short-term impacts of timber harvesting and associated activities on the
abundance of medium-sized mammals in the jarrah forest of Western
Australia. In: Craig J.L., Mitchell, N. and Saunders, D.A. (eds) Nature
Conservation 5: Conservation in the Production Environments: Managing
the Matrix. Surrey Beatty and Sons, Sydney, pp. 60-70.
Morris, K., Johnson, B., Orell, P., Gaikhorst, G., Wayne, A. and
Moro, D. (2003) Recovery of the threatened chuditch (Dasyurus
geoffroii): a case study. In: Archer M., Jones, M.E. and Dickman, C.R.
(eds) Predators with Pouches: The Biology of Carnivorous Marsupials.
CSIRO Publishing, Melbourne, pp. 435-451.
National Land and Water Resources Audit (2002) Australian
Terrestrial Biodiversity Assessment 2002. National Land and Water
Resources Audit, Canberra.
Nichols, J.D. and Williams, B.K. (2006) Monitoring for
conservation. Trends in Ecology and Evolution 21, 668-673.
Nichols, O.G. and Muir, B. (1989) Vertebrates of the jarrah forest.
In: Dell B., Havel, J.J. and Malajczuk, N. (eds) The Jarrah Forest: A
Complex Mediterranean System. Kluwer Academic Publishers, Dordrecht, pp.
Orell, P. (2004) Fauna monitoring and staff training: Western
Shield review--February 2003. Conservation Science Western Australia 5,
Osenberg, C.W., Schmitt, R.J., Holbrook, S.J., Abu-Saba, K.E. and
Flegal, A.R. (1994) Detection of environmental impacts: natural
variability, effect size, and power analysis. Ecological Applications 4,
Penman, T.D., Mahony, M.J. and Lemckert, F.L. (2005) Soil
disturbance in integrated logging operations and the potential impacts
on a fossorial Australian frog. AppliedHerpetology 2, 415-424.
Penman, T.D., Lemckert, F.L. and Mahony, M.J. (2006) Meteorological
effects on the activity of the giant burrowing frog (Heleioporus
australiacus) in south-eastern Australia. Wildlife Research 33, 35-40.
Penman, T.D., Lemckert, F.L. and Mahony, M.J. (2008) Applied
conservation management of a threatened forest dependent frog,
Heleioporus australiacus. Endangered Species Research 5, 45-53.
Pollock, K.H., Nichols, J.D., Brownie, C. and Hines, J.E. (1990)
Statistical inference for capture-recapture experiments. Wildlife
Monographs 107, 1-97.
Pollock, K.H., Nichols, J.D., Simons, T.R., Farnsworth, G.L.,
Bailey, L.L. and Sauer, J.R. (2002) Large scale wildlife monitoring
studies: statistical methods for design and analysis. Environmentrics
Recher, H.F. (1985) A diminishing resource: mature forest and its
role in forest management. In: Kikkawa, J. (ed.) Wildlife Management in
the Forests and Forest-Controlled Lands in the Tropics and Southern
Hemisphere. IUFRO and University of Queensland, Brisbane, pp. 28-33.
Rhind, S.G. (1996a) Habitat tree requirements and the effects of
removal during logging on the marsupial brush-tailed phascogale
(Phascogale tapoatafa tapoatafa) in Western Australia. Western
Australian Naturalist 21, 1-22.
Rhind, S.G. (1996b) Addendum--Errata: habitat tree requirements and
the effects of removal during logging on the marsupial brush-tailed
phascogale (Phascogale tapoatafa tapoatafa) in Western Australia.
Western Australian Naturalist 21, 1.
Rhind, S.G. (1998) Ecology of the brush-tailed phascogale in jarrah
forest of south-western Australia. Thesis, Murdoch University, Perth,
Rhind, S.G. (2002) Reproductive demographics among brush-tailed
phascogales (Phascogale tapoatafa) in south-western Australia. Wildlife
Research 29, 247-257.
Rhind, S.G. (2004) Direct impacts of timber harvesting and forest
management of the brush-tailed phascogale Phascogale tapotafa and other
arboreal marsupials in a jarrah forest of Western Australia. In: Lunney,
D. (ed.) Conservation of Australia's Forest Fauna. Royal Zoological
Society of New South Wales, Sydney, pp. 639-655.
Rhind, S.G. and Bradley, J.S. (2002) The effect of drought on body
size, growth and abundance of wild brush-tailed phascogales (Phascogale
tapoatafa) in south-western Australia. Wildlife Research 29, 235-245.
Robinson, R.M. and Williams, M.R. (2011) Forestcheck : the response
of epigeous macrofungi to silviculture in jarrah (Eucalyptus marginata)
forest. Australian Forestry 74, 288-302.
SAS Institute Inc. (2004) SAS/STAT 9.1 User's guide, Volumes
1-7. SAS Publishing, Cary, NC.
Serena, M., Soderquist, T.R. and Morris, K. (1991) The chuditch:
Dasyurus geoffroii. Department of Conservation and Land Management,
Start, T., Burbidge, A. and Armstrong, D. (1998) A review of the
conservation status of the woylie, Bettongia penicillata ogilbyi
(Marsupialia: Potoroidae) using IUCN criteria. CALMScience 2, 277-289.
Underwood, A.J., Russell, J.S. and Craig, W.O. (1996) On beyond
BACI: sampling designs that might reliably detect environmental
disturbances. In: Schmitt, R.J. and Osenberg, C.W. (eds) Detecting
Ecological Impacts. Academic Press, San Diego, pp. 151-175.
Walters, C.J. and Holling, C.S. (1990) Large-scale management
experiments and learning by doing. Ecology 71, 2060-2068.
Ward, B., Robinson, R.M., Cranfield, R.J. and Williams, M.R. (2011)
Forestcheck : the response of vascular flora to silviculture in jarrah
(Eucalyptus marginata) forest. Australian Forestry 74, 276-287.
Wardell-Johnson, G. (1986) Use of nest boxes by mardos, Antechinus
flavipes leucogaster, in regenerating karri forest in south western
Australia. Australian Wildlife Research 13, 407-417.
Wardell-Johnson, G. and Horwitz, P. (1996) Conserving biodiversity
and the recognition of heterogeneity in ancient landscapes: a case study
from south-western Australia. Forest Ecology and Management 85, 219-238.
Wardell-Johnson, G. and Nichols, O. (1991) Forest wildlife and
habitat management in southwestern Australia: knowledge, research and
direction. In: Lunney, D. (ed.) Conservation of Australia's Forest
Fauna. Royal Zoological Society of New South Wales, Sydney, pp. 161-192.
Wardell-Johnson, G., Calver, M.C., Saunders, D.A., Conroy, S. and
Jones, B. (2004) Why integration of demographic and site-based studies
of disturbance is essential for the conservation of jarrah forest fauna.
In: Lunney, D. (ed.) Conservation of Australia's Forest Fauna.
Royal Zoological Society of New South Wales, Sydney, pp. 394-417.
Wayne, A.F., Ward, C., Rooney, J. and Wheeler, I. (2000) The
immediate impacts of timber harvesting and associated activities on the
ngwayir (Pseudocheirus occidentalis) in the jarrah forest of Kingston
State Forest Block. Unpublished progress report. Western Australian
Government Department of Conservation and Land Management, Manjimup.
Wayne, A.F., Wheeler, I.B., Ward, C.G., Rooney, J.F. and Mellican,
A. (2001) The impacts of timber harvesting and associated activities on
the small terrestrial vertebrates of the jarrah forest: Kingston Project
progress report. Western Australian Government Department of
Conservation and Land Management, Manjimup.
Wayne, A.F., Cowling, A., Rooney, J.F., Ward, C.G., Wheeler, I.B.,
Lindenmayer, D.B. and Donnelly, C.F. (2005a) Factors affecting the
detection of possums by spotlighting in Western Australia. Wildlife
Research 32, 689-700.
Wayne, A.F., Cowling, A., Ward, C.G., Rooney, J.F., Vellios, C.V.,
Lindenmayer, D.B. and Donnelly, C.F. (2005b). A comparison of survey
methods for arboreal possums in jarrah forest, Western Australia.
Wildlife Research 32, 701-714.
Wayne, A.F., Cowling, A., Lindenmayer, D.B., Ward, C.G., Vellios,
C.V., Donnelly, C.F. and Calver, M.C. (2006) The abundance of a
threatened arboreal marsupial in relation to anthropogenic disturbances
at local and landscape scales in mediterranean-type forests in
south-western Australia. Biological Conservation 127, 463-476.
Webala, P., Craig, M.D., Law, B.S., Wayne, A.F. and Bradley, S.J.
(2010) Roost site selection by southern forest bat Vespadelus regulus
and Gould's long-eared bat Nyctophilus gouldi in logged jarrah
forests, south-western Australia Forest Ecology and Management 260,
Webala, P., Craig, M.D., Law, B.S., Armstrong, K.N., Wayne, A.F.
and Bradley, J.S. (2011). Bat habitat use in logged jarrah eucalypt
forests of south-western Australia. Journal of Applied Ecology 48,
Webb, G.A. (1995) Effects of logging on lizards in eucalypt forest
at Eden, New South Wales. Australian Forestry 58, 155-159.
Wheeler, R. and Priddel, D. (2009) The impact of introduced
predators on two threatened prey species: a case study from western New
South Wales. Ecological Management and Restoration 10, S117-123.
Whitford, K.R. (2001) Dimensions of tree hollows used by fauna in
the jarrah forest: improving the dimensional description of potentially
usable hollows. CALMScience 3, 499-511.
Whitford, K.R. (2002) Hollows in jarrah (Eucalyptus marginata) and
marri (Corymbia calophylla) trees: I. Hollow sizes, tree attributes and
ages. Forest Ecology and Management 160, 201-214.
Whitford, K.R. and Williams, M.R. (2000) Survival of jarrah
(Eucalyptus marginata Sm.) and marri (Corymbia calophylla Lindl.)
habitat trees retained after logging. Forest Ecology and Management
Whitford, K.R. and Williams, M.R. (2002) Hollows in jarrah
(Eucalyptus marginata) and marri (Corymbia calophylla) trees--II.
Selecting trees to retain for hollow dependent fauna. Forest Ecology and
Management 160, 215-232.
Williams, M.R. and Faunt, K. (1997) Factors affecting the abundance
of hollows in logs in jarrah forest of south-western Australia. Forest
Ecology and Management 95, 153-160.
Woinarski, J.C.Z. and Fisher, A. (1995) Wildlife of lancewood
(Acacia shirleyi) thickets and woodlands in Northern Australia. 1.
Variation in vertebrate species composition across the environmental
range occupied by lancewood vegetation in the Northern Territory.
Wildlife Research 22, 379-411.
Wyre, G. (2004) Management of the Western Shield program: Western
Shield review--February 2003. Conservation Science Western Australia 5,
Yoccoz, N.G., Nichols, J.D. and Boulinier, T. (2001) Monitoring
biological diversity in space and time. Trends in Ecology and Evolution
Zuur, A.F., Leno, E.N. and Elphick, C.S. (2010) A protocol for data
exploration to avoid common statistical problems. Methods in Ecology and
Evolution 1, 3-14.
Adrian F. Wayne (1,3), Graeme L. Liddelow (1) and Matthew R.
(1) Department of Environment and Conservation, Science Division,
Locked Bag 2, Manjimup, WA 6258, Australia
(2) Department of Environment and Conservation, Science Division,
Locked Bag 104, Bentley Delivery Centre, WA 6983, Australia
(3) Email: firstname.lastname@example.org
Revised manuscript received 27 September 2011
Table 1. Summary of Forestcheck monitoring grids according to jarrah
forest ecosystem/year of sampling, silvicultural treatment, and fox
control (number of grids subject/not subject to routine fox/baiting
out of the total number of grids for that particular ecosystem/year
x silvicultural treatment)
Year sampled and ecosystem
Treatment 2001-02 2002-03 2003-04
JS JNW-C JNW-N
Gap release 1/2 0/3 2/0
Shelterwood 1/0 0/3 3/0
Coupe buffer 1/2
> 40 y ago 1/1 2/0
harvested 0/1 0/3 1/0
Total 4/6 0/9 8/0
Year sampled and
Treatment 2004-05 2005-06 Total
Gap release 1/2 3/0 7/7
Shelterwood 1/2 2/0 7/5
Selective cut 3/0 3/0
Coupe buffer 1/0 2/2
> 40 y ago 0/1 2/0 5/2
harvested 0/2 1/0 2/6
Total 3/7 11/0 26/22
Table 2. Count of all terrestrial vertebrate taxa recorded in all
treatments from 48 Forestcheck grids
release Shelterwood cut
Species (n = 14) (n = 12) (n = 3)
Crinia georgiana 7 2
Heleioporus eyrei 13 6 1
Limnodynastes dorsalis 5 1
Litoria adelaidensis 2
Acritoscincus trilineatum 5 2
Apraisia pulchella 7 6 2
Christinus marmoratus 6 1 1
Ctenotus catenifer 1 1
Ctenotus labillardieri 6 21 2
Diplodactylus polyophthalmus 1 2
Egernia napoleonis 9 22 9
Glaphyromorphus gracilipes 1
Hemiergis initialis 1 9
Hemiergis peroni 15 8 2
Lerista spp. 49 71 3
Menetia greyii 23 34
Morethia spp. 49 38 4
Notechis scutatus 1
Parasuta gouldii 1
Pogona minor 2 3
Ramphotyphlops australis 7 10 4
Rhinoplocephalus bicolor 2 1
Tiliqua rugosa 2 6
Varanus rosenbergi 1 1
Antechinus flavipes 6 4
Bettongia penicillata 32 31
Cercartetus concinnus 7 04 7
Dasyurus geoffroii 6 8
Mus musculus 3 1
Rattus rattus 7 13
Sminthopsis spp. 7 12 1
Tachyglossus aculeatus 2 1
Trichosurus vulpecula 46 56 24
Species (n = 4) (n = 15)
Crinia georgiana 7 4
Crinia glauerti 1
Crinia subinsignifera 1
Heleioporus eyrei 3
Limnodynastes dorsalis 3 3
Litoria adelaidensis 1
Litoria moorei 1
Pseudophryne guentheri 2
Acritoscincus trilineatum 2 4
Apraisia pulchella 12
Christinus marmoratus 1 3
Ctenotus labillardieri 9
Diplodactylus polyophthalmus 2
Egernia napoleonis 1 6
Glaphyromorphus gracilipes 1
Hemiergis initialis 6
Hemiergis peroni 8 17
Hemiergis quadrillineata 1
Lerista spp. 3 41
Lialis burtonis 1
Menetia greyii 2 17
Morethia spp. 1 35
Parasuta gouldii 1
Pogona minor 1 1
Ramphotyphlops australis 2
Tiliqua rugosa 4
Varanus rosenbergi 1
Antechinus flavipes 5
Bettongia penicillata 9 22
Cercartetus concinnus 1 4
Dasyurus geoffroii 4 2
Isoodon obesulus 1
Mus musculus 4 1
Rattus fuscipes 1
Sminthopsis spp. 3 6
Trichosurus vulpecula 46 80
Table 3. Mean species richness and abundance ([+ or -] se)
vertebrates for the five forest ecosystems/years of sampling
(n = 41). N = number of grids monitored; values in the same column
followed by the same letter are not significantly different
([alpha] = 0.05).
year N Richness Abundance
JS/2001-02 7 8.42 [+ or -] 0.87 (ab) 21.69 [+ or -] 3.83 (ab)
JNW-C/2002-03 9 9.60 [+ or -] 0.91 (a) 34.93 [+ or -] 6.48 (a)
JNW-N/2003-04 8 7.81 [+ or -] 1.16 (ab) 11.44 [+ or -] 2.70 (c)
JNE/2004-05 9 6.70 [+ or -] 0.82 (b) 19.99 [+ or -] 3.29 (bc)
JB/2005-06 8 7.93 [+ or -] 1.01 (ab) 12.25 [+ or -] 2.50 (c)
Table 4. Mean species richness and abundance ([+ or -] se) of
terrestrial vertebrates for the two main silvicultural treatments
and external reference forest (n = 41). N = number of grids
monitored; values in the same column followed by the same letter
are not significantly different ([alpha] = 0.05).
Treatment N Richness Abundance
reference 15 6.34 [+ or -] 0.87 (a) 17.61 [+ or -] 3.10 (a)
Shelterwood 12 9.63 [+ or -] 0.73 (b) 21.64 [+ or -] 3.21 (a)
Gap release 14 8.31 [+ or -] 0.72 (ab) 16.36 [+ or -] 2.38 (a)
Table 5. Estimates of the number of study grids required to get
detectable effect sizes (Osenberg et al. 1994) ranging from 50% to
5% (i.e., an increase or decrease with respect to the external
reference treatment), with 95% confidence, based on the current
Forestcheck terrestrial vertebrate monitoring design and data
(n = 41 grids, 3 treatments).
Attribute Detectable effect size (%)
50 40 30 20 10 5
Species richness 12 15 24 051 200 0800
Abundance 21 33 69 168 750 3200