New Lifeline for Manning River Turtle

[GBWhite]

https://www.winghamchronicle.com.au...ifeline-from-australian-reptile-park/?cs=1551

 

[Pauls_Pythons]

Nice to read something positive on the conservation front for a change.

 

[Flaviemys purvisi]

It's a good article but it has a few inaccuracies. Nest predation by feral pigs and foxes isn't the largest threat to this species, just like in the Bellinger with georgesi, the largest threat by far to Flaviemys purvisi is the far larger and more aggressive, introduced Murray River turtle - Emydura macquarii macquarii). Flaviemys. purvisi is 55 million years old and has a generation gap of 20 years, (same as the western saw-shell - E. bellii.) This means that the surviving offspring from a single successful clutch (less than 1%) will take 20 years to reach maturity and go on to breed themselves... the generation gap of E. macquarii is less than 1/3 of that. Also, E. macquarii will breed every year whereas research has shown that only 75% of the wild F. purvisi population will breed in any one favourable season (which may only come along once or twice a decade.) We've been observing F. purvisi from as far back as 1998 and really started jumping up and down and making noise about their noticeable decline in 2011 when AFT's divers counted over 350 individual E. macquarii in less than a 1km stretch of the river. The remaining F. purvisi population is extremely isolated and fragmented and their location, rightfully is to be kept undisclosed.
It's good to see though that there's finally some action being taken and people are beginning to pile onto the bandwagon after listening to the noise we've been making about this rare little turtle for over a decade now.
It's been a productive winter with my own purvisi pairs all courting and mating for the duration. The conservation of Every single individual specimen of this species is extremely important now.

 

[GBWhite]

Here's a link to a bit on interesting reading regarding fox predation v habitat destruction v introduction of E macquarii as threats to both F purvis & M geogesi. Second link to Bellinger River Emydura is a very interesting read.

https://www.environment.nsw.gov.au/resources/threatenedspecies/determinations/FDHelmTurtES.pdf

https://www.environment.nsw.gov.au/resources/nature/schedules/BellingerEmydura.pdf

 

[Flaviemys purvisi]

Yeah, I read over those papers about 12 months ago.

 

[GBWhite]

It wasn't actually posted for you specifically Kev but yeah they're interesting because they still consider fox predation on eggs as one of if not the biggest threat to both species. Also interesting is that other than confirmation of only 3 Emydura being introduced to the Bellinger (which by the way came from the Orara River and happened during the study period) the allegation that Emydura is an introduced species can't be confirmed. In fact we were catching heaps of Emydura in the Bellinger when I first came to the area in 1975 and my local indigenous friends tell me they have been a part of their diet for a long, long time so it's more than probable that they are native to the river. Wouldn't surprise me that it's he same situation in the Manning River.

 

[Flaviemys purvisi]

Hi George. The number of juvenile turtles that can be found in the Manning, (purvisi, Emydura & longicollis) suggests that fox predation of nests isn't a huge problem at all as compared to other systems in Australia like the Murray where in many locations, no young turtles can be found at all nor have been sighted for decades. My own experiences and trips to the Manning show that the turtles have no problem breeding successfully, in the good seasons, they're (purvisi) are just being heavily outcompeted and displaced by the Emydura sp. The number of Emydura present in the system of all sizes/ages also shows that nest destruction is a very insignificant factor in this particular system. Purvisi compared to Emydura take a lot longer to mature and breed and the number of Emydura present will grow at 3 times the rate of purvisi.

As for the Bellinger snapper, their own generation gap is 10 years, half that of purvisi. Purvisi are also a lot older than georgesi. Despite the near extinction event of 2015 in the Bellinger, georgesi will recover and repopulate from such an event at twice the speed or half the time that purvisi could.

I personally believe that no Emydura sp was ever native to the Manning river system prior to human interference just as there were none native to the Sydney area. The Manning River system (as you'd know) is almost 300km south of the Bellinger, not exactly a stone's throw.