Biodiversity Assessment Technical Report



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b) Abundance

  • Classification of abundance: Low

  • Population Estimate: A few pairs.

  • Density: Approximately 1 pair/1200km2, Estimated 20-50 pairs in Victoria

  • Home Range (ha): Unknown

  • Source: C. Silveria pers. comm., Debus and Silveira (1989), Baker-Gabb in Garnett (1992)

c) Habitat Specificity

  • Classification of habitat specificy: Wide

  • Vegetation types used in the region: Most forest and woodland EVCs, especially riparian forest. Not recorded from extensively cleared and naturally open areas, alpine areas, mountain ash forest and small forest remnants.

  • Source: Debus and Silveira (1989), R. Loyn pers. comm.

DYNAMICS

Population Trend in Last Decade

  • Increasing, stable or declined: Unknown

  • Source: C. Silveira pers. comm.

Population trend since discovery by Europeans

  • Increasing, stable or declined: Possibly declined

  • Source: Lumsden et al. (1991), C. Silveira pers. comm.

SPATIAL DYNAMICS

a) Population variability

  • Classification of population variability: Unknown

  • Source: R. Loyn pers. comm.

b) Dispersal

  • Classification of powers of dispersal: High

  • Average distances dispersed: Capable of moving 100s km

  • Maximum distance dispersed: Unknown

  • Source: Debus and Silveira (1989)

LIFE HISTORY PARAMETERS

a) Reproductive output

  • Classification of reproductive output: Low

  • Age of sexual maturity (yrs): 2-3 years

  • Mean clutch/litter/brood size: 2-3 eggs

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

  • Time of year young born/hatch: Spring

  • Source: Debus and Czechura (1989), Marchant and Higgins (1993)

b) Longevity

  • Classification of lifespan: Long-lived

  • Average lifespan (yrs): Unknown

  • Maximum lifespan (yrs): >15 years

  • Source: Marchant and Higgins (1993)

c) Morphology

Adult body size



  • Weight (g): Female 590-680, male 501

  • Length (mm): Female 550-560, male 500-510

  • Source: Olsen et al. (1993)

d) Social organisation

  • Colonial or non-colonial: Usually seen singly

  • Territoriality: Nesting territories

  • Source: Debus and Czechura (1989)

e) Other

  • Nomadic, migratory, sedentary: Migratory

  • Mode of feeding: Mainly carnivore (including young birds from nests)

  • Source: Debus and Czechura (1989)



THREATS

1. Fire (planned): Ranking (1) R. Loyn pers. comm.

2. Fire (unplanned): Ranking (2) R. Loyn pers. comm.

3. Logging: Ranking (1) R. Loyn, pers. comm., Debus and Czechura (1989)

4. Introduced Species: Ranking (0)

5. Pest Control: Ranking (0)

6. Grazing: Ranking (1) R. Loyn pers. comm.

7. Disease: Ranking (-)



8. Illegal harvesting: Ranking (1) R. Loyn pers. comm., Jolly (1989)

9. Non-forestry Clearing: Ranking (1) R. Loyn pers. comm., Debus and Czechura (1989)

10. Mining/Quarrying: Ranking (-) R. Loyn pers. comm.

11. Roading: Ranking (1) R. Loyn pers. comm.

12 Recreation: Ranking (0)



13. Vandalism/Disturbance by Humans: Ranking (1) R. Loyn pers. comm., Jolly (1989)

14. Other: Ranking (-)


Current Management:

The Square-tailed Kite is classified as “vulnerable” in Victoria (CNR 1995a). There are no current management prescriptions for the species in the Central Highlands.


Comments: The Square-tailed Kite is a spring-summer visitor to Victoria, and occurs naturally in low densities (Debus and Silveria 1989, C. Silveria pers. comm.). Only a few pairs may occur within the Central Highlands. Its migration is likely to be linked to food availability; the species’ main prey is nestling passerines. The Square-tailed Kite is known to use traditional nest sites, and nests in mature living Eucalypts. It relies on an adequate supply of prey and tall trees for nesting, and threats to the species relate to loss or disturbance of these critical resources (Debus and Czechura 1989). In the Central Highlands the highest ranked threat is wildfire which results in loss of habitat and prey. Illegal shooting and egg collection have been recorded (Jolly 1989) and are minor threats to the species.

Grey Goshawk

Accipiter novaehollandiae

RARITY

a) Geographic Range

  • Classification of range size: Medium

  • Range size within region: (ha): Unknown, possibly 250 000-600 000

  • Proportion of region occupied (%): Unknown, possibly 20-50

  • Source: CNRandAHC (1994), Atlas of Victorian Wildlife, R. Loyn pers. comm.

b) Abundance

  • Classification of abundance: Low

  • Population Estimate: Possibly a few pairs

  • Density: Densities of 2-3 pairs/100km2 in optimum habitat with little disturbance recorded in Tasmania.

  • Home Range (ha): Unknown, possibly core areas of about 10km2

  • Source: Mooney and Holdsworth (1988), C. Silveira pers. comm.

c) Habitat Specificity

  • Classification of habitat specificity: Wide

  • Vegetation types used in the region: Wet forests and gullies (including those containing Mountain Grey Gum), riparian forest, occasionally woodlands, dry forest, suburban parks and wooded farmlands.

  • Source: Emison et al. (1987), R. Loyn pers. comm.

DYNAMICS

Population Trend in Last Decade

  • Increasing, stable or declined: Unknown

  • Source: R. Loyn pers. comm.

Population trend since discovery by Europeans

  • Increasing, stable or declined: Possibly declined

  • Source: Lumsden et al. (1991), C. Silveira pers. comm.

SPATIAL DYNAMICS

a) Population variability

  • Classification of population variability: Unknown

  • Source: R. Loyn pers. comm.

b) Dispersal

  • Classification of powers of dispersal: High

  • Average distances dispersed: Unknown

  • Maximum distance dispersed: Unknown

  • Source: R. Loyn pers. comm.

LIFE HISTORY PARAMETERS

a) Reproductive output

  • Classification of reproductive output: Low

  • Age of sexual maturity (yrs): 2-3 years

  • Mean clutch/litter/brood size: 2-4

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

  • Time of year young born/hatch: September-December
    Mooney and Holdsworth (1988) suggest one third of adults may not breed in any one year

  • Source: Burton et al. (1994), Marchant and Higgins (1993)

b) Longevity

  • Classification of lifespan: Unknown

  • Average lifespan (yrs): Unknown

  • Maximum lifespan (yrs): Unknown

  • Source: R. Loyn pers. comm.

c) Morphology

Adult body size



  • Weight (g): Female 530-859, male 283-450

  • Length (mm): Female 500-550, male 380-420

  • Source: Olsen et al. (1993)

d) Social organisation

  • Colonial or non-colonial: Monogamous pairs

  • Territoriality: Territorial when breeding

  • Source: Marchant and Higgins (1993)

e) Other

  • Nomadic, migratory, sedentary: Established pairs sedentary

  • Mode of feeding: Carnivore, occasional scavenger and insectivore

  • Source: Marchant and Higgins (1993)



THREATS

1. Fire (planned): Ranking (1) R. Loyn pers. comm.

2. Fire (unplanned): Ranking (1) R. Loyn pers. comm.

3. Logging: Ranking (2) R. Loyn pers. comm. 4. Introduced Species: Ranking (0)

5. Pest Control: Ranking (2) R. Loyn pers. comm.

6. Grazing: Ranking (-)

7. Disease: Ranking (-)

8. Illegal harvesting: Ranking (-)



9. Non-forestry Clearing: Ranking (1) R. Loyn pers. comm.

10. Mining/Quarrying: Ranking (-)



11. Roading: Ranking (1) R. Loyn, pers. comm.

12 Recreation: Ranking (1) R. Loyn pers. comm.

13. Vandalism/Disturbance by Humans: Ranking (1) R. Loyn pers. comm.

14. Other: Ranking (-)


Current Management:

The Grey Goshawk is classified as “rare” in Victoria (CNR 1995a). There are no current management prescriptions for the species in the Central Highlands.


Comments: The Grey Goshawk is rarely recorded in the Central Highlands and the population possibly consists of only a few pairs. In Tasmania, adult Grey Goshawks are known to primarily use old growth wet forests for hunting and nesting. Some birds may also nest in mixed-age or young regrowth forest if old growth trees are present (Mooney and Holdsworth 1988, Brereton and Mooney 1994). Suitable sheltered perches for hunting may also be important. The loss and modification of such habitat by logging and clearing for agriculture and development is likely to be detrimental to the species (Brereton and Mooney 1994). While the species may tolerate some level of disturbance near nest sites (eg. selective logging, limited road building), nests are deserted following intense/direct disturbance (Mooney and Holdsworth 1988).
In the Central Highlands loss of habitat as a result of logging is a moderate threat to the Grey Goshawk (R. Loyn pers. comm.). In Victoria the species is known to take rabbits in farmland near forest edges, and reduction of rabbit numbers through pest control measures may have an adverse affect on the population (R. Loyn pers comm). Illegal shooting of birds is considered a significant threat in Tasmania (Brereton and Mooney 1994) but is not likely to be significant in the Central Highlands. Other minor threats including secondary poisoning through consumption of baited prey and contamination by pesticides (Mooney 1988, Mooney and Holdsworth 1988).

White-bellied Sea-Eagle

Haliaeetus leucogaster

RARITY

a) Geographic Range

  • Classification of range size: Unknown, possibly large

  • Range size within region: (ha): Unknown

  • Proportion of region occupied (%): Unknown
    There are less than 30 records of the species within the Central Highlands. While the species can range widely and occur in a wide range of habitats, its use of the Central Highlands is largely unknown.

  • Source: Atlas of Victorian Wildlife, P. Clunie pers. comm.

b) Abundance

  • Classification of abundance: Low

  • Population Estimate: Unknown
    Only one known breeding pair currently known within Central Highlands.
    Possibly 100 breeding pairs or less in Victoria

  • Density: Unknown. Estimates for other areas of Victoria vary greatly

  • Home Range (ha): Unknown in Victoria.

  • Source: R. Bilney pers. comm., Clunie (1994), Atlas of Victorian Wildlife

c) Habitat Specificity

  • Classification of habitat specificity: Wide

  • Vegetation types used in the region: Usually nests near water, in tall live or dead trees (including River Red Gum Eucalyptus camaldulensis, Forest Red Gum E. tereticornis and Southern Mahogany E. botryoides). Usually tall open forest and woodland, may occur in open areas (grassland, heath) and urban areas, rarely within dense vegetation.

  • Source: Emison and Bilney (1982), Marchant and Higgins (1993)

DYNAMICS

Population Trend in Last Decade

  • Increasing, stable or declined: Unknown

  • Source: P. Clunie pers. comm.

Population trend since discovery by Europeans

  • Increasing, stable or declined: Declined
    Decline over coastal range could be presumed due to clearing

  • Source: Lumsden et al. (1991), Clunie (1994)

SPATIAL DYNAMICS

a) Population variability

  • Classification of population variability: Low

  • Source: P. Clunie pers. comm.

b) Dispersal

  • Classification of powers of dispersal: High
    Immature birds may disperse widely

  • Average distances dispersed: Unknown

  • Maximum distance dispersed: Unknown

  • Source: Emison et al. (1987)

LIFE HISTORY PARAMETERS

a) Reproductive output

  • Classification of reproductive output: Low

  • Age of sexual maturity (yrs): 4-5 years

  • Mean clutch/litter/brood size: 1-2 eggs

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

  • Time of year young born/hatch: July-October (in Gippsland Lakes area)

  • Source: Bilney and Emison (1983), Mooney (1986)

b) Longevity

  • Classification of lifespan: Long-lived

  • Average lifespan (yrs): Unknown

  • Maximum lifespan (yrs): Unknown, possibly 17 years

  • Source: Mooney (1986)

c) Morphology

Adult body size



  • Weight (g): Female 3100-3900g, male 2000-2420g

  • Length (mm): Female 800-850mm, male 750-770mm

  • Source: Olsen et al. (1993)

d) Social organisation

  • Colonial or non-colonial: Generally alone or in pairs

  • Territoriality: Defend small territory around nest during breeding season

  • Source: Marchant and Higgins (1993)

e) Other

  • Nomadic, migratory, sedentary: Sedentary, established pairs

  • Mode of feeding: Carnivore, opportunistic

  • Source: Marchant and Higgins (1993)



THREATS

1. Fire (planned): Ranking (-) P. Clunie pers. comm.

2. Fire (unplanned): Ranking (-)



3. Logging: Ranking (1) P. Clunie, pers. comm.

4. Introduced Species: Ranking (0)



5. Pest Control: Ranking (1) P. Clunie pers. comm.

6. Grazing: Ranking (-)

7. Disease: Ranking (-)

8. Illegal harvesting: Ranking (0)



9. Non-forestry Clearing: Ranking (1) P. Clunie, pers. comm.

10. Mining/Quarrying: Ranking (-) P. Clunie, pers. comm.

11. Roading: Ranking (-) P. Clunie, pers. comm.

12 Recreation: Ranking (1) P. Clunie, pers. comm.

13. Vandalism/Disturbance by Humans: Ranking (2) P. Clunie pers. comm.

14. Other: Interspecific competition Ranking (1) Wiersma (1996).
Current Management:

The White-bellied Sea-Eagle is listed under the Flora and Fauna Guarantee Act 1988 and an Action Statement has been prepared (Clunie 1994). Intended management actions include: annual surveys of known beeding sites to determine breeding success over time, identify population trends, determine critical habitat, encourage research particularly in relation to heavy metal levels in the species and the effect of food chain contamination on survival and reproduction, undertake a population viability analysis once more information is known about dispersal activity, and the protection of known nest sites including buffer zones which will be incorporated into Forest Management Plans and encourage protection of breeding sites on private land through extension programs or conservation covenants.


Comments: White-bellied Sea-Eagles occur in low densities over much of Victoria. They are most common along the coast from Gabo Island to Wilsons Promontory, with birds also occuring along the Murray and Goulburn Rivers and sometimes over inland areas with impoundments. The species is found in a range of habitat types, and usually nests near water in tall live or dead trees. There are few records of the species from the Central Highlands, only one breeding pair is currently known.
White-bellied Sea-Eagles are sensitive to disturbance, particularly during the breeding season when disturbance can lead to reduced breeding success (Dennis and Lashmar 1996). As a result activities including recreation, mining, logging and agriculture which disturb or encroach into its habitat represent a threat. Loss of habitat components such as nest trees also represent a threat (Mooney 1986). Birds may nest in suboptimal habitat but under these conditions breeding success can be reduced (Bilney and Emison 1983). Eggshell thinning has been recorded due to past DDT use; while this may not have caused significant population declines (Olsen et al. 1993a), it is an issue to be considered. Deliberate shooting has been recorded (Mooney 1986) although is unlikely to be a significant threat within the Central Highlands. The significance of poisoning (direct or secondary), and food chain contamination by heavy metals is also unknown. Competition with Wedge-tailed Eagles for nest sites and food has been recorded (Wiersma 1996), although its significance is unclear.

Barking Owl

Ninox connivens

RARITY

a) Geographic Range

  • Classification of range size: Medium

  • Range size within region: (ha): Unknown, possibly 200 000-500 000

  • Proportion of region occupied (%): Unknown, possibly < 10
    There are approximately 50 records post 1980 within the Central Highlands, although very few breeding records. Misidentification is a significant issue.
    Source: Atlas of Victorian Wildlife, CNR and AHC (1994), R. Loyn pers. comm.

b) Abundance

  • Classification of abundance: Low

  • Population Estimate: Unknown, probably < 10 pairs
    Population estimate of < 100 pairs in Victoria

  • Density: Unknown

  • Home Range (ha): Approximately 100ha

  • Source: P. Peake pers. comm. in Robinson (1994), R. Loyn pers. comm.

c) Habitat Specificity

  • Classification of habitat specificity: Narrow

  • Vegetation types used in the region: Dry forest and woodlands, open forest and wooded farmlands. Particularly near riverine and swampy areas. Rarely wet forest and then usually only near clearings.

  • Source: Emison et al. (1987), Schodde and Mason (1980), Kavanagh et al. (1995)

DYNAMICS

Population Trend in Last Decade

  • Increasing, stable or declined: Unknown

  • Source: R. Loyn pers. comm.

Population trend since discovery by Europeans

  • Increasing, stable or declined: Possible decline
    Clearing and degradation of habitat for agriculture

  • Source: Lumsden et al. (1991), Robinson (1991)

SPATIAL DYNAMICS

a) Population variability

  • Classification of population variability: Low

  • Source: R. Loyn pers. comm.

b) Dispersal

  • Classification of powers of dispersal: Probably high

  • Average distances dispersed: Unknown

  • Maximum distance dispersed: Unknown
    Some may be dispersive, linked to fluctuations in food

  • Source: Robinson (1994), R. Loyn pers. comm.

LIFE HISTORY PARAMETERS

a) Reproductive output

  • Classification of reproductive output: Low

  • Age of sexual maturity (yrs): > 2 years

  • Mean clutch/litter/brood size: 1-3 eggs

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

  • Time of year young born/hatch: July-November

  • Source: Schodde and Mason (1980), Robinson (1994)

b) Longevity

  • Classification of lifespan: Possibly long-lived

  • Average lifespan (yrs): Unknown

  • Maximum lifespan (yrs): Unknown

  • Source: R. Loyn pers. comm.

c) Morphology

Adult body size



  • Weight (g): 425-485 females, 425-510 males

  • Length (mm): 370-440 females, 350-450 males

  • Source: Schodde and Mason (1980)

d) Social organisation

  • Colonial or non-colonial: Breeding pairs

  • Territoriality: Yes

  • Source: Schodde and Mason (1980)

e) Other

  • Nomadic, migratory, sedentary: Sedentary

  • Mode of feeding: Carnivore, insectivore

  • Source: Schodde and Mason (1980)



THREATS

1. Fire (planned): Ranking (-)

2. Fire (unplanned): Ranking (-)

3. Logging: Ranking (-) R. Loyn pers. comm.

4. Introduced Species: Ranking (0) R. Loyn pers. comm.



5. Pest Control: Ranking (1) R. Loyn pers. comm.

6. Grazing: Ranking (2) R. Loyn pers. comm.

7. Disease: Ranking (-)

8. Illegal Harvesting: Ranking (0) R. Loyn pers. comm.

9. Non-forestry Clearing: Ranking (2) R. Loyn pers. comm., Robinson (1994).

10. Mining/Quarrying: Ranking (-)

11. Roading: Ranking (-)

12 Recreation: Ranking (-)

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

14. Other: Ranking (-)


Current Management:

The Barking Owl has received a final recommendation for listing under the Victorian Flora and Fauna Guarantee Act 1988.


Comments: There are approximately 50 post-1980 records and four breeding records of Barking Owls within the Central Highlands. However, misidentification of the species is a significant issue (R. Loyn, pers. comm.) and this is likely to be an overestimate. Recent surveys within the Central Highlands covering all forest types, failed to record this species (R. Loyn pers. comm.). Barking Owls are conspicuous birds which range widely, and densities are likely to be low (R. Loyn pers. comm.).
The Barking Owl is mainly recorded in dry, open forest and woodlands and wooded farmlands; frequently in habitat with moderate tree cover including wooded farmland near forests or along ecotones of large forest blocks (Emison et al. 1987, P. Peake pers. comm. in Robinson 1994). The species appears to have a preference for hunting in open habitat (Robinson 1994) but may roost among dense vegetation. Birds primarily nest in large, hollow-bearing trees (Schodde and Mason 1980).
Loss and fragmentation of habitat through clearing is a moderate threat to Barking Owls in the Central Highlands. The species is known to utilise broad strips of riverine forest along major creeks however, isolated, narrow strips of linear habitat do not appear to be used (Robinson 1994). Kavanagh et al. (1995) suggest the Barking Owl may be tolerant to intermediate levels of disturbance.
Reduced availability of large hollow-bearing trees as a result of logging and lack of habitat regeneration due to grazing which will limit future habitat availability are minor threats to the Barking Owl. Rabbits can be an important food source (P. Peake, pers. comm. in Robinson 1994), and the implications of pest control are unknown. However, Kavangh et al. (1995) suggest the species has a wide dietary flexibility.


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