Acknowledgements V Summary VI 1 General introduction 1 1 Barred Galaxias 1




НазваниеAcknowledgements V Summary VI 1 General introduction 1 1 Barred Galaxias 1
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2.3 Results

2.3.1 Site identification


A total of 217 survey sites were selected for field inspection. None of these were identified from post-fire aerial images as stream-flows at the time of photography were low and barriers could therefore not be identified by the presence of white water. Also, unburnt riparian vegetation and the local topography shaded and inhibited the view of streams in many areas. One site was marked on a topographic map as a waterfall (Figure 6), and the location of an additional barrier (on Sylvia Creek) was provided by an officer from the Toolangi DSE Office. The remaining 215 survey sites were selected from topographic maps.


Figure 6. Evelyn Falls on Koala Creek, which prevents upstream movement of trout (Image: David Bryant).


2.3.2 Site assessment


The list of 217 potential sites were prioritised by the presence of known barriers, geographic location and catchment area and 61 of the sites, including those with larger upstream catchment areas, were surveyed between May 2010 and March 2011 (Figures 7 & 8). Of these, none had recently been heavily burnt by bushfire or had sustained timber harvesting within their upstream catchment in the past 20 years. Three (5%) sites were found to be dry and 36 (59 %) sites had no fish (Table 1; Figure 8). Of the 22 where fish were present, trout (Brown Trout, Rainbow Trout, or both species) were recorded from 20 (33%) sites, one (2%) site (FT045) contained a previously unknown population of Barred Galaxias, and one (2%) site (FT023) contained a population of Mountain Galaxias (Table 1; Figure 8).

Of the 36 fish-less sites, 7 (19%) had instream barriers located further downstream, equating to five barriers in total as two streams had two sites each (Table 1). These included: Koala and Silvia creeks (FT001, FT005, FT018) and Torbreck River (FT061), where the presence of barriers was previously known but their locations were reconfirmed and physical structure investigated; Taponga River (FT033), where a barrier was found within the fish survey reach; and, Shaw Creek (FT024, FT043), where a barrier was identified by surveying further downstream after examining contour lines on a topographic map. All barriers were considered effective as trout were not detected upstream. Conversely, barriers were assumed either absent or ineffective at the 20 sites which contained trout in the assessment reach. The presence of barriers at the remaining 29 fish-less sites was undetermined as none were found during fish assessments and time constraints prevented additional downstream investigation at these sites (Table 1).

Water quality parameters measured at all sites where similar to those at known Barred Galaxias sites (Raadik 2000, 2002, Raadik, T.A. unpublished data).

Figure 7. Examples of survey sites: tributary of Big River (left); and Shaw Creek (right) (Images: Michael Nicol).

Figure 8. Distribution of the 61 sites surveyed including their assessment result and fish species recorded. Blue squares indicate suitable sites. Note that multiple symbols overlap in some areas.

Table 1. Details of the 61 potential Barred Galaxias translocation sites surveyed and their translocation suitability. BG – Barred Galaxias; Brch – branch; BT – Brown Trout; Crk – creek; d/s – downstream; MG – Mountain Galaxias; Nth – north; R – river; RT – Rainbow Trout; Sth – south; Trib – tributary; TSp – unidentified trout species; ? – undetermined.

Site no.

Waterbody (Catchment)

Date sampled

Latitude (°S)

Longitude (°E)

Altitude (m)

Catchment Area (km2)

Fish species present

Barrier present downstream

Translocation suitability

FT001

Koala Crk
(Big R)

17/05/2010

-37.5176

145.9122

910

8.3

No fish

Yes

Yes – immediate

FT005

Koala Crk

(Big R)

18/05/2010

-37.4982

145.8878

1200

2.5

No fish

Yes

Yes – immediate

FT024

Shaw Crk

(Big R)

28/07/2010

-37.6348

146.0216

830

3.5

No fish

Yes

Yes – immediate

FT043

Shaw Crk

(Big R)

7/10/2010

-37.6417

146.0308

960

1.1

No fish

Yes

Yes – immediate

FT033

Taponga R

(Big R)

11/08/2010

-37.4578

145.9998

620

1.4

No fish

Yes

Yes – immediate

FT018

Sylvia Crk Nth Brch

(Yea R)

16/07/2010

-37.5104

145.5197

810

0.1

No fish

Yes

Yes – immediate

FT061

Torbreck R Sth Brch, trib.

(Big R)

23/03/2011

-37.4873

145.9190

960

2.4

No fish (BG ds)

Yes

Potentially – genetic research required

FT014

Westcott Crk

(Sunday Crk)

6/07/2010

-37.3717

145.1555

630

5.1

No fish

?

Potentially– barrier survey required d/s

FT017

Number One Crk

(Yea R)

9/07/2010

-37.5308

145.3589

510

2.7

No fish

?

Potentially– barrier survey required d/s

FT013

Comet Crk

(Sunday Crk)

6/07/2010

-37.3717

145.1555

560

2.1

No fish

?

Potentially– barrier survey required d/s

FT046

Big R, trib.

(Big R)

27/10/2010

-37.4584

146.1110

600

2

No fish

?

Potentially– barrier survey required d/s

FT031

Big R, trib.

(Big R)

11/08/2010

-37.4635

146.0579

640

1.7

No fish

?

Potentially– barrier survey required d/s

FT015

Number One Crk

(Yea R)

9/07/2010

-37.5290

145.3445

540

1.6

No fish

?

Potentially– barrier survey required d/s

FT060

Tom Burns Crk

(Rubicon R)

1/02/2011

-37.3888

145.8398

1010

1.3

No fish

?

Potentially– barrier survey required d/s

FT022

Dungaree Crk

(Big R)

27/07/2010

-37.6100

146.1508

1060

1

No fish

?

Potentially– barrier survey required d/s

FT044

Fryer Crk

(Big R)

26/10/2010

-37.3812

146.1258

840

1

No fish

?

Potentially– barrier survey required d/s

FT051

Twenty Five Mile Crk, trib.

(Big R)

14/12/2010

-37.4712

146.1188

680

1

No fish

?

Potentially– barrier survey required d/s

FT036

Taponga R, trib.

(Big R)

12/08/2010

-37.4658

146.0137

650

0.9

No fish

?

Potentially– barrier survey required d/s

FT050

Wombat Crk

(Goulburn R)

13/12/2010

-37.5146

146.1697

1010

0.9

No fish

?

Potentially– barrier survey required d/s

FT035

Wild Dog Crk

(Big R)

12/08/2010

-37.4700

146.0125

710

0.8

No fish

?

Potentially– barrier survey required d/s

FT003

Torbreck R Sth Brch, trib.

(Big R)

17/05/2010

-37.4777

145.9203

930

0.8

No fish

?

Potentially– barrier survey required d/s

FT004

Torbreck R Sth Brch, trib.

(Big R)

17/05/2010

-37.4718

145.9241

960

0.8

No fish

?

Potentially– barrier survey required d/s

FT058

Ryan Crk

(Goulburn R)

1/02/2011

-37.5237

146.1596

1050

0.7

No fish

?

Potentially– barrier survey required d/s

FT048

Goulburn R

(Goulburn R)

29/10/2010

-37.5362

146.2036

1010

0.6

No fish

?

Potentially– barrier survey required d/s

FT029

Big R, trib.

(Big R)

10/08/2010

-37.4617

146.0736

690

0.5

No fish

?

Potentially– barrier survey required d/s

FT010

Second Crk

(Big R)

18/05/2010

-37.4420

145.9418

1080

0.4

No fish

?

Potentially– barrier survey required d/s

FT007

Torbreck R Nth Brch, trib.

(Big R)

18/05/2010

-37.4559

145.9377

1040

0.4

No fish

?

Potentially– barrier survey required d/s

FT008

Torbreck R Nth Brch, trib.

(Big R)

18/05/2010

-37.4548

145.9387

1040

0.4

No fish

?

Potentially– barrier survey required d/s

FT009

Torbreck R N Brch, trib.

(Big R)

18/05/2010

-37.4479

145.9415

1080

0.4

No fish

?

Potentially– barrier survey required d/s

FT006

Deep Crk

(Big R)

18/05/2010

-37.4621

145.9301

1050

0.3

No fish

?

Potentially– barrier survey required d/s

FT002

Torbreck R Sth Brch, trib.

(Big R)

17/05/2010

-37.4818

145.9171

950

0.3

No fish

?

Potentially– barrier survey required d/s

FT056

Big R, trib.

(Big R)

15/12/2010

-37.5254

146.0791

530

4

No fish

No

Potentially – barrier installation required

FT020

Sylvia Crk Nth Brch

(Yea R)

20/07/2010

-37.5236

145.5214

680

2.1

No fish

No

Potentially – barrier installation required

FT040

Taponga R, trib.

(Big R)

22/09/2010

-37.4561

145.9975

620

0.7

No fish

No

Potentially – barrier installation required

FT032

Big R, trib.

(Big R)

11/08/2010

-37.4605

146.0644

600

0.5

No fish

No

Potentially – barrier installation required

FT030

Big R, trib.

(Big R)

10/08/2010

-37.4576

146.0654

620

0.3

No fish

No

Potentially – barrier installation required

FT039

Taponga R, trib.

(Big R)

22/09/2010

-37.4560

145.9976

620

0.8

RT

No

Potentially – barrier installation and trout removal required

FT041

Dudley Crk

(Big R)

23/09/2010

-37.4729

145.9787

640

1.4

RT

No

Potentially – barrier installation and trout removal required

FT038

Taponga R

(Big R)

21/09/2010

-37.4573

146.0029

580

1.9

TSp

No

Potentially – barrier installation and trout removal required

FT021

Sylvia Crk Sth Brch

(Yea R)

20/07/2010

-37.5337

145.5237

700

2.3

BT

No

Potentially – barrier installation and trout removal required

FT019

Sylvia Crk Nth Brch

(Yea R)

16/07/2010

-37.5261

145.5214

660

2.8

BT

No

Potentially – barrier installation and trout removal required

FT034

Wild Dog Crk

(Big R)

11/08/2010

-37.4591

146.0040

600

3.3

RT

No

Potentially – barrier installation and trout removal required

FT053

Goulburn R

(Goulburn R)

14/12/2010

-37.5462

146.2128

880

3.3

BT

No

Potentially – barrier installation and trout removal required

FT059

Little Crk

(Big R)

1/02/2011

-37.5397

146.0141

550

3.4

RT

No

Potentially – barrier installation and trout removal required

FT025

Spring Crk

(Big R)

29/07/2010

-37.6103

146.1511

1110

3.6

RT

No

Potentially – barrier installation and trout removal required

FT055

Big R, trib.

(Big R)

15/12/2010

-37.5068

146.0600

580

3.7

RT

No

Potentially – barrier installation and trout removal required

FT026

Boundary Crk

(Big R)

30/07/2010

-37.5805

146.0242

600

3.7

RT

No

Potentially – barrier installation and trout removal required

FT037

Big R, trib.

(Big R)

21/09/2010

-37.4640

146.0663

560

4.4

TSp

No

Potentially – barrier installation and trout removal required

FT054

25 Mile Crk

(Big R)

15/12/2010

-37.4918

146.1244

620

5.2

RT

No

Potentially – barrier installation and trout removal required

FT042

Shaw Crk

(Big R)

5/10/2010

-37.6228

146.0170

710

5.7

BT RT

No

Potentially – barrier installation and trout removal required

FT028

Big R, trib.

(Big R)

10/08/2010

-37.4741

146.0696

550

5.8

BT RT

No

Potentially – barrier installation and trout removal required

FT011

Torbreck R Sth Brch

(Big R)

19/05/2010

-37.4829

145.9256

790

6.6

BT

No

Potentially – barrier installation and trout removal required

FT052

Moonlight Crk

(Goulburn R)

14/12/2010

-37.4542

146.1750

650

9.6

RT

No

Potentially – barrier installation and trout removal required

FT057

Dear Hound Crk

(Big R)

28/10/2010

-37.5091

146.0938

460

13

RT

No

Potentially – barrier installation and trout removal required

FT027

Shaw Crk
(Big R)

30/07/2010

-37.5897

146.0243

610

17.5

BT

No

Potentially – barrier installation and trout removal required

FT012

Torbreck R Sth Brch, trib.

(Big R)

19/05/2010

-37.4857

145.9209

880

2.5

BT (BG upstream)

No

No – barrier installation and trout removal required

FT045

Moonlight Crk, trib.

(Goulburn R)

27/10/2010

-37.4500

146.1423

910

1.3

BG

?

No – barrier survey required d/s

FT023

Oaks Crk

(Big R)

27/07/2010

-37.6394

146.1299

1150

1.1

MG

?

No

FT016

Number Three Crk

(Yea R)

9/07/2010

-37.5113

145.3859

400

3.8

DRY

?

No

FT047

Ryan Crk, trib.

(Goulburn R)

28/10/2010

-37.4873

146.1443

820

1.3

DRY

?

No

FT049

Frenchmans Crk, trib.

(Big R)

13/12/2010

-37.5852

146.1744

1130

0.4

DRY

?

No



2.3.3 Selection of suitable translocation sites


Based on assessment criteria, six (10%) sites assessed were found suitable for the immediate translocation of Barred Galaxias (Table 1; Figure 8). These are located in the Koala Creek (FT001, FT005), Shaw Creek (FT024, FT043), Sylvia Creek north branch (FT018), and upper Taponga River (FT033) catchments (Table 1). In particular, these sites were located upstream of a suitable instream barriers, did not have a resident fish fauna, had good catchment and streamflow conditions and ranged in catchment area from 0.1–8.3 km2.

A further 24 (39%) sites lacked fish but require further assessment of the presence and condition of potential downstream barriers before further assessment against the suitability criteria and possible inclusion as potential translocation sites (Table 1; Figure 8). Five (8%) other sites (FT020, FT030, FT032, FT040, FT056) lacked fish but also lacked instream barriers (Table 1; Figure 8). These sites, in catchments varying from 0.3–4 km2, require the installation of an appropriate instream barrier to prevent the upstream movement of trout before they can be included as potential translocation sites.

The upper reaches of a tributary of the Torbreck River, south branch (FT061) lacked fish and had a barrier downstream, however a small population of Barred Galaxias currently exists below this barrier. This site may be included as a potential translocation site once the genetic structure of the resident Barred Galaxias population is determined.

Nineteen sites are currently unsuitable for translocation as they contain trout and do not have an effective downstream barrier. The remaining six sites were rejected as suitable for translocation because they were dry (three sites), or contained populations of native fish species (three sites: FT012, Torbreck River south branch tributary; FT023, Oaks Creek; and, FT045, Moonlight Creek) (Table 1, Figure 8).

Selection of two trial translocation catchments


Four catchments were initially identified as suitable for use in the trial translocation of Barred Galaxias (Table 1). They ranged in upstream catchment area from 0.1 km2 (Sylvia Creek north branch) to 8.3 km2 (Koala Creek). Koala Creek was rejected from use in the translocation trial because smaller catchments were preferable to keep the scale of the trial manageable. It was also considered more valuable to be set aside for a large and critical future translocation of Barred Galaxias once procedures for effective translocations had been established.

Consequently, Shaw Creek and the upper Taponga River (catchment areas of 3.5 and 1.4 km2 respectively) were chosen as the trial translocation catchments (see Chapter 3), being the next two consecutively smaller catchments
(Table 1).

The upper Taponga River site (FT033) was surveyed a second time over an 800 m reach upstream from the instream barrier, targeting habitat suitable for trout (i.e. pools). Again no trout were found and suitable conditions and habitat were confirmed for Barred Galaxias. Similarly, Shaw Creek was surveyed a second time, at approximately 1.75 km’s upstream of the original survey location (FT043). No trout were found in a 100 m reach and suitable conditions and habitat for Barred Galaxias also existed.

2.3.4 Distribution of Mountain Galaxias


An unexpected outcome of the field assessments was the lack of populations of Mountain Galaxias recorded within the study area, with the species found at only one of the 61 sites (Table 1; FT023, Oaks Creek). This species is widespread in foothill to montane areas of north-eastern Vitoria (Raadik 2011). Comparison of Figure 2 with Figure 8 indicates that Mountain Galaxias are almost as rare in distribution as Barred Galaxias in the upland reaches of the south-east portion of the Goulburn River system, particularly in the Big River catchment.
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