the online meeting place for all who love our amphibians and reptiles
Home Page Live Forums Archived Forums Site Search Identify Record Donate Projects Links
Forum Home Forum Home > Herpetofauna Native to the UK > Pool Frog
  New Posts New Posts RSS Feed - Pool Frog programme coming up
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Pool Frog programme coming up

 Post Reply Post Reply Page  <1234 6>
Author
Message
liamrussell View Drop Down
Senior Member
Senior Member
Avatar

Joined: 13 Jan 2005
Status: Offline
Points: 100
Post Options Post Options   Thanks (0) Thanks(0)   Quote liamrussell Quote  Post ReplyReply Direct Link To This Post Posted: 06 Aug 2012 at 11:37am
Thought I'd sleep on this and give it some serious consideration as I was a bit ambivalent before. After thinking about it I came to the conclusion that I would be in favour of controlling grass snakes in this situation for two main reasons. I'm not advocating grass snake control as a permanent situation, but just until the pool frogs can develop the strength and depth of (meta)population structure which would reflect a true natural population. 

Regardless of whether the pool frog reintroduction should have been undertaken in the first place, now that it has been, it should be given every chance of success. Considerable amounts of time, money and effort and good science has been invested in the programme and to let that go to waste now due to problem which could be solved would be an extremely bad use of resources and a shame really.

Secondly, and perhaps more compellingly; in the long-term it will benefit both pool frogs and grass snakes for the pool frog population to be robust. Pool frogs occupy a slightly different niche to other native anurans and I'm told that the site didn't have many amphibians prior to the reintroduction. Therefore if the grass snakes eat all the pool frogs there will be little food left and their population will crash as they either starve or are forced to disperse in to less suitable habitat with a low likelihood of survival. If the pool frog population is allowed to build to a state where it reflects a robust natural population, then you would expect a normal predator-prey relationship to become established which would mean stable populations of both pool frogs and grass snakes would be present on the site with a good long-term likelihood of survival. Given this, I think it would be prudent to control grass snakes at the site whilst the pool frog population is in a vulnerable early stage.


Back to Top
GemmaJF View Drop Down
Admin Group
Admin Group
Avatar

Joined: 25 Jan 2003
Location: Essex
Status: Offline
Points: 4188
Post Options Post Options   Thanks (0) Thanks(0)   Quote GemmaJF Quote  Post ReplyReply Direct Link To This Post Posted: 06 Aug 2012 at 1:27pm
@Caleb yes I agree that nobody has actually put forward that grass snake etc should be controlled in any way - I am just considering if these populations are monitored at what point would someone suggest control. Is there much point monitoring predators if no action at all were to be taken. I originally asked 'what are the options?' and then went on to discuss one possibility.

You are right also regarding the overall decline. I was referring to the loss of the final animals which is also well documented and related to a lack of management and collection at one site. As far as I remember at the time it was only speculation that the population may have been native. I would consider the re-introduction programme is starting at a similar point and working back the other way (i.e avoiding publishing the location, appropriate management etc), I guess the team involved have not persuaded anyone to re-flood the entire fens (yet Wink)

@ Liam - thanks for taking the time to put across your view which I really appreciate. I met an  ornithologist a few years back whilst working on a site. He related to me a project where Magpies were controlled by trapping to encourage rare song birds. After several years it was noted that the target species were actually declining faster. More common small birds had though increased in number. The conclusion drawn was the Magpie 'baddies' were actually controlling the more common species in the past which gave the rarer species a chance at the site. Just one example where what appeared to be a simple solution backfired in reality. Caleb noted that there were few existing amphibians at the site, so they are present. Removing their 'control' predator could for example have the same effect as the Magpie site even in a case where the animals occupy a different niche?
Back to Top
Caleb View Drop Down
Senior Member
Senior Member


Joined: 11 Apr 2011
Status: Offline
Points: 653
Post Options Post Options   Thanks (0) Thanks(0)   Quote Caleb Quote  Post ReplyReply Direct Link To This Post Posted: 06 Aug 2012 at 2:30pm
Originally posted by GemmaJF GemmaJF wrote:

I was referring to the loss of the final animals which is also well documented and related to a lack of management and collection at one site.


It was the final animals I was referring to when I mentioned the water table. That site had dozens of ponds that dried up in summer after summer in the 80s and 90s.

It seems a bit much to blame management when the species became extinct before it was accepted as a native- no-one could have been expected to improve habitat for what was then seen as an  alien.

Is there any real evidence that collection had an effect? No-one knew the Norfolk pool frogs were anything special until after they became extinct, and anyone wanting to catch green frogs had plenty more high-profile sites to choose from.

Originally posted by GemmaJF GemmaJF wrote:

Is there much point monitoring predators if no action at all were to be taken


Well, this is also intended to be the first of several reintroductions, so the data could be applied to the next site(s). The predator data may be able to show if introductions of adults, juveniles, tadpoles or spawn are most likely to succeed, how many individuals should be released, at what time of year, and/or how often.

I'd like to think that this introduction could be allowed to fail and used as a lesson for future efforts rather than 'controlling' other natives or chucking in animals year after year to die off or be eaten. It seems to be generating enough data to make it well worth while even if this does turn out to be the case (which looks unlikely, given that it is already generating a slow increase in the number of pool frogs in the wild).



Back to Top
GemmaJF View Drop Down
Admin Group
Admin Group
Avatar

Joined: 25 Jan 2003
Location: Essex
Status: Offline
Points: 4188
Post Options Post Options   Thanks (0) Thanks(0)   Quote GemmaJF Quote  Post ReplyReply Direct Link To This Post Posted: 06 Aug 2012 at 2:38pm
Well I think you will find Caleb there was one individual who did think they were native and was making a lot of fuss about the final decline, sadly  nobody was listening at the time but then history is written by the victors eh?
Back to Top
Caleb View Drop Down
Senior Member
Senior Member


Joined: 11 Apr 2011
Status: Offline
Points: 653
Post Options Post Options   Thanks (0) Thanks(0)   Quote Caleb Quote  Post ReplyReply Direct Link To This Post Posted: 06 Aug 2012 at 3:37pm
It may have been too late even then. As I understand it, the last sighting of a native pool frog in Norfolk was 1991 or 1992, so they were probably already in terminal decline by the time their native status was being considered. Charles Snell's 'Neglected Native' article was published in 1994.
Back to Top
Richard2 View Drop Down
Senior Member
Senior Member


Joined: 01 Dec 2010
Status: Offline
Points: 285
Post Options Post Options   Thanks (0) Thanks(0)   Quote Richard2 Quote  Post ReplyReply Direct Link To This Post Posted: 06 Aug 2012 at 6:43pm

The last surviving native Pool Frog was the male who was christened 'Lucky', isn't that right? You probably all know this story well. It makes me think of Waiting for Godot. Didn't Lucky die shortly before the clinching evidence emerged that Pool Frogs were a native species and could therefore be replenished with an imported population? This report, however, suggests that Lucky did breed with some imported females, and that therefore the bloodline was preserved. Is that right? Are some of the introduced specimens genetically descended in part from the native population?

 
Back to Top
Caleb View Drop Down
Senior Member
Senior Member


Joined: 11 Apr 2011
Status: Offline
Points: 653
Post Options Post Options   Thanks (0) Thanks(0)   Quote Caleb Quote  Post ReplyReply Direct Link To This Post Posted: 07 Aug 2012 at 9:34am
Originally posted by Richard2 Richard2 wrote:

Are some of the introduced specimens genetically descended in part from the native population?


Sadly not. I'm told that 'Lucky' bred with some frogs from the Netherlands, but never with any Scandinavian females. All the animals released originate from specimens recently collected in Sweden.

Back to Top
Richard2 View Drop Down
Senior Member
Senior Member


Joined: 01 Dec 2010
Status: Offline
Points: 285
Post Options Post Options   Thanks (0) Thanks(0)   Quote Richard2 Quote  Post ReplyReply Direct Link To This Post Posted: 07 Aug 2012 at 10:08am
Thanks - that's interesting. Does anyone know what did happen to Lucky's progeny?
Back to Top
liamrussell View Drop Down
Senior Member
Senior Member
Avatar

Joined: 13 Jan 2005
Status: Offline
Points: 100
Post Options Post Options   Thanks (0) Thanks(0)   Quote liamrussell Quote  Post ReplyReply Direct Link To This Post Posted: 07 Aug 2012 at 3:14pm
@Gemma, I guess that's always going to be a possibility and the only way to find out is to closely monitor the situation and adapt the management as necessary. From what I know about the site (John Baker did a talk about if at the HWM this year) there aren't many other amphibians on the site (newts) but I guess the habitat improvement may have made it more suitable for all species.

@Caleb - I think if the first reintroduction was 'allowed to fail' the chances of obtaining any more funding for subsequent reintroductions would be slim to say the least...
Back to Top
GemmaJF View Drop Down
Admin Group
Admin Group
Avatar

Joined: 25 Jan 2003
Location: Essex
Status: Offline
Points: 4188
Post Options Post Options   Thanks (0) Thanks(0)   Quote GemmaJF Quote  Post ReplyReply Direct Link To This Post Posted: 07 Aug 2012 at 7:19pm
I would agree with that last point Liam. If the purpose of monitoring the grass snakes is also to prevent 'chucking in' animals in the future as Caleb suggests, it also raises the point that perhaps it should of occurred before the reintroduction rather than after it!
Back to Top
 Post Reply Post Reply Page  <1234 6>
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 11.06
Copyright ©2001-2016 Web Wiz Ltd.

This page was generated in 0.047 seconds.