Biodiversity Assessment Technical Report



Yüklə 2,94 Mb.
səhifə37/42
tarix27.08.2017
ölçüsü2,94 Mb.
1   ...   34   35   36   37   38   39   40   41   42

Leadbeater’s Possum

Gymnobelideus leadbeateri

RARITY

a) Geographic Range

  • Classification of range size: Medium

  • Range size within region: (ha): 170 000 - 235 000

  • Proportion of region occupied (%): 14 - 20

  • Source: Macfarlane and Seebeck (1991)

b) Abundance

  • Classification of abundance: Medium - this is dependent on the quality of the habitat

  • Population Estimate: 7500 ± 2300, estimated for the population in 1980

  • Density: 1.6-2.9 possums/ha

  • Home Range (ha): 1.3-1.9

  • Source: Smith (1984a), Smith et al. in Smith and Lindenmayer (1992)

c) Habitat Specificity

  • Classification of habitat specificity: Narrow - mainly confined to wet and damp forests

  • Vegetation types used in the region: Montane Damp Forest, Montane Wet Forest, Wet Forest, Riparian Forest, Subalpine Woodland

  • Source: Smales (1994), Jelinek et al. (1995), Macfarlane et al. (1995)

DYNAMICS

Population Trend in Last Decade

  • Increasing, stable or declined: Probably declined, due a decline in nest tree availability and the progression of current favorable habitat to a structurally less-suitable successional stage

  • Source: Smith et al. in Macfarlane et al. (1995), Smith and Lindenmayer (1988), Lindenmayer (1990)

Population trend since discovery by Europeans

  • Increasing, stable or declined: Declined

  • Source: Lumsden et al. (1991)

SPATIAL DYNAMICS

a) Population variability

  • Classification of population variability: Low

  • Source: Smith (1984a)

b) Dispersal

  • Classification of powers of dispersal: High, juvenile females disperse further

  • Average distances dispersed: Unknown, juvenile females typically beyond natal home range

  • Maximum distance dispersed: Unknown

  • Source: Smith (1984a)

LIFE HISTORY PARAMETERS

a) Reproductive output

  • Classification of reproductive output: Low

  • Age of sexual maturity (yrs): 1.5

  • Mean clutch/litter/brood size: 1.4

  • Mean no of clutches/litters/broods per year: 2

  • Time of year young born/hatch: April-June, October-December (majority of births)

  • Source: Smith (1984a)

b) Longevity

  • Classification of lifespan: Short-lived

  • Average lifespan (yrs): Unknown, high mortality in juvenile females

  • Maximum lifespan (yrs): 4 females, >7 males

  • Source: Smith (1984a)

c) Morphology

Adult body size



  • Weight (g): 100-135(122) Spring, 110-166(133) Autumn

  • Length (mm): 150-170(160)

  • Source: Smith in Strahan (1995)

d) Social organisation

  • Colonial or non-colonial: Colonial

  • Territoriality: Females territorial, transient females unsuccessful breeding

  • Source: Smith (1984a)

e) Other

  • Nomadic, migratory, sedentary: Sedentary

  • Mode of feeding: Insectivore (arthropods), Exudivore

  • Source: Smith (1984b)



THREATS

1. Fire (planned): Ranking (2) Macfarlane and Seebeck (1991), Lindenmayer (1990), Milledge et al. (1991)



2. Fire (unplanned): Ranking (3) Lindenmayer and Possingham (1994), Macfarlane et al. (1995)

3. Logging: Ranking (3) Andrew et al. (1984), Fleming et al. (1979), Smith and Lindenmayer (1988), Macfarlane and Seebeck (1991), Lumsden et al. (1991), LCC (1991), Smith and Lindenmayer (1992), Lindenmayer (1995)

4. Introduced Species: Ranking (1)

5. Pest Control: Ranking (0)

6. Grazing: Ranking (0)

7. Disease: Ranking (0)

8. Illegal Harvesting: Ranking (0)

9. Non-forestry Clearing: Ranking (0)

10. Mining/Quarrying: Ranking (0)

11. Roading: Ranking (1) Macfarlane and Seebeck (1991)

12 Recreation: Ranking (0)

13. Vandalism/Disturbance by Humans: Ranking (0)

14. Other: Enhanced Greenhouse Effect Ranking (2)) Lindenmayer (1990) Bennett et al. (1991), Macfarlane and Seebeck (1991)
Current management:

Leadbeater’s Possum is listed under the Victorian Flora and Fauna Guarantee Act 1988 and the Commonwealth Endangered Species Protection Act 1992. An Action Statement (Macfarlane et al. 1995), a Draft Management Strategy (Macfarlane and Seebeck 1991) and Management Guidelines which are applicable only to timber production forests, are currently being implemented. Management actions include: the establishment of a zoning system with specific prescriptions relating to the assessment of habitat, size and shape of coupes, buffer establishment and the protection of all hollow-bearing trees regardless of zoning classification. All known colonies are to be protected and other management activities including roading and reforestation are to be addressed. Intended management actions outlined in the Action Statement include: establishment of 21 Leadbeater’s Possum Management Units, resource assessment surveys to determine the extent and distribution of current optimum and potentially optimum habitat, a revision of the current zoning system to reflect habitat changes over time, logging coupe assessment, retention of buffer strips, protection of hollow trees, salvage logging plans, operational trials of retained overwood silvicultural systems, reserve establishment, continuation of research to assist and improve long-term conservation, captive management planning, social and economic planning and continuation of community education (Macfarlane et al. 1995).


Comments: The distribution of Leadbeater’s Possum is centered on the montane ash forests (Eucalyptus regnans, E. delegatensis and E. nitens) of the Central Highlands (Macfarlane et al. 1995). There is a single colony in a lowland swamp forest (E. camphora and E. ovata) within Yellingbo State Nature Reserve (Smales 1994) and a few records from Lake Mountain within snow gum woodland (E. pauciflora) (Jelinek 1995).
The habitat of Leadbeater’s Possum includes large old trees for breeding and shelter, a vegetation structure that facilitates movement, and available food (Macfarlane et al. 1995). In ash forests Leadbeater’s Possum forages for arboreal arthropods beneath the decorticating bark of the eucalypts and the sap of Acacia species (Acacia dealbata, A. melanoxylon and A. frigescens). A dense layer of Acacias also provides a suitable structure for movement (Smith 1984a). The montane ash forests of the Central Highlands are a valued timber resource and loss of hollow trees as a consequence of logging is a major threat to Leadbeater’s Possum (Smith and Lindenmayer 1992, Lindenmayer 1995). Harvesting prescriptions stipulate that all live hollow trees are to be left standing and protected on logging coupes. However, these trees are often killed during the hot regeneration burns used for seed bed preparation in these forests, and are highly vulnerable to windthrow and collapse. The longevity of these habitat trees post logging requires research (Lindenmayer et al. 1990, Rhind 1996)
Although wildfire has been important in the development of suitable habitat for Leadbeater’s Possum, widespread, severe wildfire was predicted to have a major negative impact on the persistence of the species. This impact is particularly evident in areas with little old-growth forest (Lindenmayer and Possingham 1994) and is a major threat to the species (Macfarlane et al. 1995). A contraction in the range of Leadbeater’s Possum as well as E. regnans and E. delegatensis was predicted by models of the likely influence of the Enhanced Greenhouse Effect (Lindenmayer 1990), and is a moderate threat to the species.

Common Bent-wing Bat

Miniopteris schreibersii blepotis

RARITY

a) Geographic Range

  • Classification of range size: Medium

  • Range size within region: (ha): 182 000 - 325 000

  • Proportion of region occupied (%): 15 -27

  • Source: Atlas of Victorian Wildlife, Lumsden et al. (1991), CNR and AHC (1994)

b) Abundance

  • Classification of abundance: Medium

  • Population Estimate: 5 000 - 10 000

  • Density: Unknown

  • Home Range (ha): Unknown

  • Source: L. Lumsden pers. comm.

c) Habitat Specificity

  • Classification of habitat specificity: Narrow, given the roosting requirements (dependence on mineshafts) of this species

  • Vegetation types used in the region: Damp Forest, Riparian Forest, Foothill Forest Complex, Grassy Dry Forest, Floodplain Riparian Woodland

  • Source: Lumsden et al. (1991)

DYNAMICS

Population Trend in Last Decade

  • Increasing, stable or declined: Declined, due to destruction, closing and natural collapse of mineshafts within the region

  • Source: L. Lumsden pers. comm.

Population trend since discovery by Europeans

  • Increasing, stable or declined: Increased, the construction of mineshafts has resulted in an increase in suitable roost sites.

  • Source: Lumsden et al. (1991)

SPATIAL DYNAMICS

a) Population variability

  • Classification of population variability: Low

  • Source: Lumsden pers. comm.

b) Dispersal

  • Classification of powers of dispersal: High

  • Average distances dispersed: 200km, juveniles dispersal from Nargun’s Cave, East Gippsland to the region

  • Maximum distance dispersed: 240 km

  • Source: Lumsden et al. (1991)

LIFE HISTORY PARAMETERS

a) Reproductive output

  • Classification of reproductive output: Low

  • Age of sexual maturity (yrs): 2 females, 1 males

  • Mean clutch/litter/brood size: 1

  • Mean no of clutches/litters/broods per year: 1

  • Time of year young born/hatch: December

  • Source: Dwyer (1963)

b) Longevity

  • Classification of lifespan: Long-lived

  • Average lifespan (yrs): Unknown

  • Maximum lifespan (yrs): 20

  • Source: Purchase (1982)

c) Morphology

Adult body size



  • Weight (g): 13-17

  • Length (mm): 52-58

  • Source: Dwyer in Strahan (1995)

d) Social organisation

  • Colonial or non-colonial: Colonial

  • Territoriality: Unknown

  • Source: Dwyer (1966a)

e) Other

  • Nomadic, migratory, sedentary: Adult females are migratory, seasonally to Nargun’s maternity cave, East Gippsland, Males and first year females are sedentary

  • Mode of feeding: Insectivore (flying insects)

  • Source: Dwyer and Hamilton-Smith (1965), Vestjens and Hall (1977), L. Lumsden pers. comm.


THREATS

1. Fire (planned): Ranking (-) L. Lumsden pers. comm.

2. Fire (unplanned): Ranking (-) L. Lumsden pers. comm.

3. Logging: Ranking (-) Law (1996), L. Lumsden pers. comm.



4. Introduced Species: Ranking (2) Dwyer (1964), Dwyer (1966b), Hall (1982), L. Lumsden pers. comm.

5. Pest Control: Ranking (2) Dunsmore et al. (1974), Menkhorst and Lumsden in Menkhorst (1995), L. Lumsden pers. comm.

6. Grazing: Ranking (0) L. Lumsden pers. comm.

7. Disease: Ranking (0) L. Lumsden pers. comm.

8. Illegal Harvesting: Ranking (0) L. Lumsden pers. comm.



9. Non-forestry Clearing: Ranking (1) L. Lumsden pers. comm.

10. Mining/Quarrying: Ranking (2) Lumsden et al. (1991), L. Lumsden pers. comm.

11. Roading: Ranking (0) L. Lumsden pers. comm.

12. Recreation: Ranking (0) L. Lumsden pers. comm.

13. Vandalism/Disturbance by Humans: Ranking (3) Seebeck and Hamilton-Smith (1967), Hall (1982), Lumsden et al. (1991), Menkhorst and Lumsden in Menkhorst (1995), L. Lumsden pers. comm.

14. Other: Collapse of mineshafts and overgrown entrances: Ranking (3) L. Lumsden pers. comm.
Current Management:.

The Common Bent-wing Bat is listed under the Victorian Flora and Fauna Guarantee Act 1988, and an Action Statement is being prepared. During determination of National Estate Values of the Central Highlands, old mines used by colonial or roosting bats were identified as key fauna habitat (CNR and AHC 1994). The conservation principal is the maintainence of key fauna habitats within the Central Highlands project area.


Comments: The Common Bent-wing Bat is a fast flying, highly mobile aerial insectivore. Most available information is related to roosting; very little is known about other habitat requirements and ecology. The species is relatively widespread but is considered threatened due to its dependence on a small number of maternity caves (two known in the State) and overwintering sites (L. Lumsden pers. comm.)
Within the Central Highlands there are no maternity sites of the Common Bent-wing Bat, but there are important roost sites (Lumsden et al. 1991). Males and first year females use these sites all year round while adult females travel to maternity sites (Nargun’s Cave) from December to March then return to overwinter in the Central Highlands.
Common Bent-wing Bats go into torpor during winter. Colonial overwintering sites have had as many as 2000 individuals recorded (Seebeck and Hamilton-Smith 1967). During this time the species is particularly vulnerable to human disturbance, including the deliberate closure of mineshaft entrances for safety reasons near areas of human habitation, which can result in mortality and is a major threat. Collapse of mineshafts and blockage of entrances by vegetation which inhibits bat access, are also major threats to the species (Lumsden pers. comm.).
Moderate threats to the Common Bent-wing Bat in the Central Highlands include the reworking of mines (L. Lumsden pers. comm.), predation by introduced species, bats have been recorded being taken by feral cats as they leave roosts, and poisoning through cumulation of pesticides (Menkhorst and Lumsden in Menkhorst 1995). The effects of forestry practices on this species are unknown (L. Lumsden pers. comm.).

Eastern Horseshoe Bat

Rhinolophus megaphyllus

RARITY

a) Geographic Range

  • Classification of range size: Small

  • Range size within region: (ha): 60 000

  • Proportion of region occupied (%): 5

  • Source: Atlas of Victorian Wildlife, CNR and AHC (1994)

b) Abundance

  • Classification of abundance: Low

  • Population Estimate: < 500

  • Density: Unknown

  • Home Range (ha): Unknown

  • Source: L. Lumsden pers. comm.

c) Habitat Specificity

  • Classification of habitat specificity: Narrow given roosting requirements (dependence on mineshafts)

  • Vegetation types used in the region: Grassy Dry Forest

  • Source: Lumsden et al. (1991)

DYNAMICS

Population Trend in Last Decade

  • Increasing, stable or declined: Declined, due to natural collapse of mineshafts within the region

  • Source: L. Lumsden pers. comm.

Population trend since discovery by Europeans

  • Increasing, stable or declined: Increased, due to the construction of mineshafts

  • Source: Kerle (1979), Lumsden et al. (1991)

SPATIAL DYNAMICS

a) Population variability

  • Classification of population variability: Low

  • Source: L. Lumsden pers. comm.

b) Dispersal

  • Classification of powers of dispersal: Low, individuals rarely move far from their roosts however the species is thought to be capable of long distance movements.

  • Average distances dispersed: Unknown

  • Maximum distance dispersed: Unknown

  • Source: Dwyer (1966c), Lumsden and Menkhorst in Menkhorst (1995)

LIFE HISTORY PARAMETERS

a) Reproductive output

  • Classification of reproductive output: Low

  • Age of sexual maturity (yrs): 2-3 females, 2 males

  • Mean clutch/litter/brood size: 1

  • Mean no of clutches/litters/broods per year: 1

  • Time of year young born/hatch: November, December

  • Source: Purchase and Hiscox (1960), Dwyer (1966c), Young (1975)

b) Longevity

  • Classification of lifespan: Long-lived

  • Average lifespan (yrs): Unknown

  • Maximum lifespan (yrs): Unknown, closely related European species of the same genus (different species) can live up to 30 years.

  • Source: L. Lumsden pers. comm.

c) Morphology

Adult body size



  • Weight (g): 7-14

  • Length (mm): 42-58

  • Source: Pavey and Young in Strahan (1995)

d) Social organisation

  • Colonial or non-colonial: Colonial

  • Territoriality: Unknown, but unlikely

  • Source: Dwyer (1966c), L. Lumsden pers. comm.

e) Other

  • Nomadic, migratory, sedentary: Probably sedentary

  • Mode of feeding: Insectivore

  • Source: Vestjens and Hall (1977), L. Lumsden pers. comm.


THREATS

1. Fire (planned): Ranking (-) L. Lumsden pers. comm.

2. Fire (unplanned): Ranking (-) L. Lumsden pers. comm.

3. Logging: Ranking (-) Law (1996), L. Lumsden pers. comm.



4. Introduced Species: Ranking (2) L. Lumsden pers. comm.

5. Pest Control: Ranking (2) Dunsmore et al. (1974), L. Lumsden pers. comm.

6. Grazing: Ranking (0) L. Lumsden pers. comm.

7. Disease: Ranking (0) L. Lumsden per. comm.

8. Illegal Harvesting: Ranking (0) L. Lumsden pers. comm.

9. Non-forestry Clearing: Ranking (0) L. Lumsden pers. comm.

10. Mining/Quarrying: Ranking (2) Lumsden et al. (1991), L. Lumsden pers. comm.

11. Roading: Ranking (0) L. Lumsden pers. comm.

12. Recreation: Ranking (0) L. Lumsden pers. comm.

13. Vandalism/Disturbance by Humans: Ranking (3) Lumsden et al. (1991), Lumsden and Menkhorst in Menkhorst (1995), L. Lumsden pers. comm.

14. Other: Mineshaft collapse and entrance overgrown Ranking (3) L. Lumsden pers. comm.


Current Management:

The Eastern Horseshoe Bat is classified as a “Restricted Colonial or Roosting Species” (CNR 1995a). During determination of National Estate Values of the Central Highlands, old mines used by colonial or roosting bats were identified as key fauna habitat (CNR and AHC 1994). The conservation principal is the maintainence of such habitats within the Central Highlands project area.


Comments: Like the Common Bent-wing Bat, the Eastern Horseshoe Bat is dependent on caves and mineshafts for roosting and breeding. Within the Central Highlands the species is at the western most limit of its range within Victoria. With the construction of mines it appears that the range of the species has expanded into the region since European settlement (L. Lumsden pers. comm.).
The Eastern Horseshoe Bat is a slow flying species which does not make long journeys between roost sites. Heavily pregnant females have been trapped in the Eildon area 200km from the nearest known maternity colony (Lumsden et al. 1991). Given the known flight pattern and movements of this species it is thought that there may be a maternity site within the Central Highlands. If a maternity colony is found within the Central Highlands this site will be very important for the conservation of the species within the region (Lumsden et al. 1991).
Major threats to the Eastern Horseshoe Bat within the Central Highlands relate to the species’ roosting requirements and include disturbance at the roost by humans, loss of habitat through mineshaft collapse and overgrown entrances, and loss of habitat through reworking of old mines (Lumsden et al. 1991, L. Lumsden pers. comm.) Predation by feral animals (particularly cats) and poisoning through cumulation of pesticides (Dunsmore et al. 1974) are moderate threats to the species and L. Lumsden pers. comm.).

Large-footed Myotis

Myotis macropus

RARITY

a) Geographic Range

  • Classification of range size: Medium

  • Range size within region: (ha): 40 000 - 130 000

  • Proportion of region occupied (%): 3 - 11

  • Source: Atlas of Victorian Wildlife, Lumsden et al. (1991), CNR and AHC (1994)

b) Abundance

  • Classification of abundance: Low

  • Population Estimate: Unknown

  • Density: Unknown

  • Home Range (ha): Unknown

  • Source: L. Lumsden pers. comm.

c) Habitat Specificity

  • Classification of habitat specificity: Narrow

  • Vegetation types used in the region: Riparian Forest Complex, Floodplain Riparian Woodland

  • Source: Lumsden et al. (1991)

DYNAMICS

Population Trend in Last Decade

  • Increasing, stable or declined: Unknown

  • Source: L. Lumsden pers. comm.

Population trend since discovery by Europeans

  • Increasing, stable or declined: Unknown

  • Source: Lumsden et al. (1991)

SPATIAL DYNAMICS

a) Population variability

  • Classification of population variability: Low

  • Source: L. Lumsden pers. comm.

b) Dispersal

  • Classification of powers of dispersal: Unknown, but no recorded long-distance movements

  • Average distances dispersed: Unknown

  • Maximum distance dispersed: Unknown

  • Source: L. Lumsden pers. comm.

LIFE HISTORY PARAMETERS

a) Reproductive output

  • Classification of reproductive output: Low

  • Age of sexual maturity (yrs): 1 or 2

  • Mean clutch/litter/brood size: Probably 1

  • Mean no of clutches/litters/broods per year: 1 or 2

  • Time of year young born/hatch: Heavily pregnant females have been recorded October and lactating females have been recorded in March

  • Source: Lumsden and Menkhorst in Menkhorst (1995), L. Lumsden pers. comm.


Yüklə 2,94 Mb.

Dostları ilə paylaş:
1   ...   34   35   36   37   38   39   40   41   42




Verilənlər bazası müəlliflik hüququ ilə müdafiə olunur ©azkurs.org 2020
rəhbərliyinə müraciət

    Ana səhifə