Green Treefrog Expanding Range

[manumuskin]

In I believe 2012 a study was done on the expanding Green Treefrog population that had recently "Jumped" the Delaware River and had shown up in Salem county and extreme western Cumberland county. Well it appears they have also jumped the Cohansey.Last night Whipoorbill did a thirty minute recording of which here is a snippet at Back Neck rd which would roughly be about here https://maps.njpinebarrens.com/#lat=39.37338202810728&lng=-75.32663125198366&z=15&type=nj2015&gpx= which makes them now much further east then at least we had heard them before.I know of Pine Barren Treefrog locations in the vicinity of Dividing Creek so their about to bump in to each other it seems.Now their habitat preferences may keep them apart.PB"s of course preferring bogs and cedar swamps though I have seen them in decidedly deciduous and more alkaline environments and the Greens like reed marshes and even brackish water so they my never meet.But if they do and hybridize what would it sound like? PB"s "Wonk" Greens "Wank" would the hybrids Wink? Wenk?Woonk?or Wunk?
I present to you a Green Treefrog symphony conducted and recorded by Whipoorbill!

PS there is also a Copes Grey Treefrog in there as well.

 

[NJChileHead]

Hey Al, great find, and really interesting! Regarding the hybridization in NJ, there was a thread about this a few years ago: https://forums.njpinebarrens.com/threads/pbtf-and-green-tree-frog-range-overlap.9947/

I read a few years back about hybrids between the two in Florida, specifically Blackwater River State Forest. I thought I remembered also reading about them in Appalachicola, but I might be mistaken. Here's a link to a picture that someone claims is a hybrid (not sure the criteria): https://www.flickr.com/photos/nclarkii/3116496460

Another picture, describes the call as similar to a PBTF: https://www.flickr.com/photos/fins72/14350990236

Here's some literature from the 80's, the abstract confirms their hybrids: https://www.jstor.org/stable/1444890?seq=1#page_scan_tab_contents

...and here's a copy-paste for an abstract to a paper that might be of interest: it shows that each species prefers their own, but with certain caveats. Pretty interesting.

"The results of a cross between the tree frogs Hyla andersonii and H. cinerea indicate a high level of genetic compatibility. Reproductive contact between the two species in the area of sympatry in North Carolina is minimal because of breeding habitat differences. The mating calls of the two species are similar, in many respects, but differ in average call-repetition rate and in spectral composition. In discrimination experiments with females of both species, each animal initially responded to the mating calls of a male of its species. However, females of H. andersonii often responded to the calls of H. cinerea when these were closer and thus relatively more intense than conspecific calls. Females of H. cinerea were more selective in that they consistently responded to conspecific calls even when those of H. andersonii were closer. Hybridization between the two species may occur in areas where habitat isolation breaks down and mixed breeding aggregations form."

I'm interested now in finding out how low of a pH the green treefrog can tolerate as far as breeding. Hopefully this won't be of any consequence to our PBTF populations.

 

[manumuskin]

It's not my find.Whipoorbill found them and sent me the recording. Funny you mention Blackwater and Apalachicola NF.Thats where I went on vacation last January.Pine Barrens Dixie style. Also it does not surprise me that Green Treefrogs and PB treefrogs will respond to each others calls.PB treefrogs respond to my calls which I know are less the perfect.
I have found PB's in out of character habitats such as clay pits and sand washes but never in a brackish reed marsh.I have never found greens in anything but reeds at least not in NJ.Have seen them in cypress swamps down south.Wonder what a hybrid would look like or sound like?