PWCS T4 project proposal: on the Green Golden Bell Frog · Green & Golden Bell Frog in NSW – 1995...
Transcript of PWCS T4 project proposal: on the Green Golden Bell Frog · Green & Golden Bell Frog in NSW – 1995...
PWCS T4 project proposal:Impacts on the Green & Golden
Bell Frog
Prof Graham H. Pyke (UTS)Representing the NSW Frog &
Tadpole Study Group
Main points
• GGBF critically endangered, within NSW, within the Hunter region and at Kooragang
• Single highly‐significant population of GGBFs on Kooragang/ Ash islands; it needs to be managed as such
• Assessing impacts of human activities on GGBF populations rests on breeding habitat
• T4 project will probably lead to population extinction; ‘death by several cuts’
• Contribution of proposed offset area to GGBF conservation is close to zero
GGBF‐ Heading for extinction
• Up to 1995‐ over 80% loss
Green & Golden Bell Frog in NSW –1995 to 2007
• Populations23% lost
• Only about 40 populations remaining in 2007, out of thousands
• More disappeared since 2007
GGBFs in Upper Hunter
• 8 recorded sites
• Possibly all gone
• One site uncertain
GGBFs in Middle Hunter
• 8 recorded sites
• Probably all gone
GGBFs in Lower Hunter
• Probably only Kooragang/ Ash Island still extant
• Sig population
GGBFs on Kooragang/ Ash Island
• Scattered records of GGBFs
• Single, large population
• Development areas treated as separate
GGBF population size on Kooragang/ Ash Island
• The trend is in the wrong direction!
1,995 2,000 2,005 2,010 2,015YEAR
0
200
400
600
800
1,000
# G
GB
F ad
ults
GGBF breeding and assessing human impacts
NO:• Calling (by males)• Eggs• Immatures• AdultsYES:• Tadpoles• Metamorphs
Impacts on GGBFs on Kooragang island
• GGBF breeding habitat lostBHPB
1.4ha => 0.7haNCIG
0.8ha
Impacts on GGBFs on Kooragang island
• GGBF breeding habitat lostBHPB & NCIG
1.5ha PWCS
5.1haDeath by three cuts
GGBFs in Ramsar wetland
• Kooragang population declines => Fewer GGBFs in Ramsarwetland
No worries? – New breeding habitat on
the way
• Success unlikely & will take timeRecipe not worked out
Previous such attempts have mostly failed
Max success rate only ~10%
Outcome requires at least 3 years
Proposed Brundee offset area:Contribution to GGBF conservation?
• NegligibleGGBF
records few & restricted in location
No breeding habitat
Potential to develop breeding habitat
Impact of proposed T4 project on GGBF
• Likely extinction of Kooragang/ Ash Island population
• Negligible contribution to GGBF conservation from proposed offset area
T4 bad news for GGBF