fox or black rat?

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muskiemagnet
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fox or black rat?

Post by muskiemagnet »

here is a picture sent to me by a friend that is going to acquire it. the pic is bad.

Image

the head seems too broad for a black rat. however the white chin screams black rat. the blotching looks fox to me. aberrant fox? black rat?

-ben
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chrish
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Re: fox or black rat?

Post by chrish »

That is an obsoleta (Black Rat) through and through.
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Antonsrkn
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Re: fox or black rat?

Post by Antonsrkn »

I have to agree with Chris, I have seen photos of black rats with that blotching before and one in person with not quite as distinct blotches as that but pretty close.
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Bryan Hamilton
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Re: fox or black rat?

Post by Bryan Hamilton »

Unless of course you have some genetic data....

I agree, black rat fo sho.
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justinm
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Re: fox or black rat?

Post by justinm »

In Southern Illinois into Kentucky you will see Black Rats that have a lot of yellow and grey on them. This could be from that area? I've seen them looking like this before. I've seen Black Rats with the same blotches in orange in Kansas and Missouri. They're a snake that has a huge range and a lot of variability.

Justin
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Nick Scobel
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Re: fox or black rat?

Post by Nick Scobel »

This snake looks a lot more like a obsoleta/vulpina hybrid to me. The dark coloration is certainly indicative of a black rat, but the head shape, post ocular stripes, and blotches on the back all scream fox snake. Just my $0.02.
Geqqo
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Re: fox or black rat?

Post by Geqqo »

boy that's a tough one. there are examples of black rats with as pronounced a pattern as this individual but jeez if you just showed me the head (I assume it is a Wisconsin animal) and no other portion of the body I would venture it is a fox.
ChadHarrison
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Re: fox or black rat?

Post by ChadHarrison »

Nick Scobel wrote:This snake looks a lot more like a obsoleta/vulpina hybrid to me. The dark coloration is certainly indicative of a black rat, but the head shape, post ocular stripes, and blotches on the back all scream fox snake. Just my $0.02.
I agree with Nick. If you are in an area where the ranges overlap, I'm almost sure it's an intergrade. Those post ocular stripes don't lie.
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Don Becker
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Re: fox or black rat?

Post by Don Becker »

It's 100% Black Rat.
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Cole Grover
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Re: fox or black rat?

Post by Cole Grover »

ChadHarrison wrote:I'm almost sure it's an intergrade
It would be a hybrid, not an "intergrade" under those circumstances. The Pantherophis obsoletus and vulpinus clades are distinct on the basis of phylogeny and morphology regardless of the species concept you subscribe to. An "intergrade" would indicate a zone of non-differentiation between two adjacent morphotypes (AKA, subspecies) in the case of primary intergradation, or the re-melding of characteristics between two parapatric populations which have recently come back into contact following a period of allopatry. Just FYI.
ChadHarrison wrote:Those post ocular stripes don't lie.
True, but they can say either, "P. obsoletus!" or "P. vulpinus!"

This snake isn't the nicest looking obsoletus in the world, but that's what it is.

-Cole
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muskiemagnet
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Re: fox or black rat?

Post by muskiemagnet »

pretty sure it came from wisconsin. i'll have troy try to get that info. when he gets the snake i'll post better pics.

-ben
troy hibbitts
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Re: fox or black rat?

Post by troy hibbitts »

LTC and CB obsoleta typically have smaller and shorter heads than their wild-caught bretheren because head shape in obsoleta is phenotypically plastic. Wild snakes eat a diet of far larger rodents and birds than do captive snakes, and develop a large head. Captives raised from juveniles or hatchlings never get the diet of larger prey items, exposure to UV which allows them to produce D3 which enables proper calcium metabolism all of which leads to the shortened head shape seen in many captive obsoleta . . . like this one.

No need to invoke hybridization at all - this is a black rat that is a LTC that has never eaten anything larger than a weanling mouse, hasn't had its food supplemented by D3, and therefore has a fore-shortened snout.
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Cole Grover
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Re: fox or black rat?

Post by Cole Grover »

troy hibbitts wrote:LTC and CB obsoleta typically have smaller and shorter heads than their wild-caught bretheren because head shape in obsoleta is phenotypically plastic. Wild snakes eat a diet of far larger rodents and birds than do captive snakes, and develop a large head. Captives raised from juveniles or hatchlings never get the diet of larger prey items, exposure to UV which allows them to produce D3 which enables proper calcium metabolism all of which leads to the shortened head shape seen in many captive obsoleta . . . like this one.

No need to invoke hybridization at all - this is a black rat that is a LTC that has never eaten anything larger than a weanling mouse, hasn't had its food supplemented by D3, and therefore has a fore-shortened snout.
Exactly. Also, pressing the snout against the side of the cage can create that short, stubby snout like this animal has.

-Cole
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Re: fox or black rat?

Post by troy hibbitts »

D3 (not UVB) is required by reptiles, birds, and mammals for proper calcium metabolism and bone health. Reptiles, birds, and mammals all synthesize D3 in their skins. Those that are nocturnal or that live near the poles must get their D3 from thier diets.

It is true that most snakes get most of their D3 from their food, but remember that all vertebrates produce D3 from UV. Also consider that obsoleta do quite a bit of basking in the wild - they aren't particularly nocturnal - so at least some of their D3 must come from UVB synthesis of D3 (the exact amount produced has not been studied, AFAIK). Add to that, the problem with lab mice diet is that lab mice are D3 poor themselves whereas wild birds and rodents are not. Pile all that up, you have recipe for at least minor skeletal abnormalities, as seen with the "dinky head" common to LTC or CB obsoleta.

Metabolic bone disease is just the extreme end of the spectrum of calcium deficiency in bones. Just as an analogy, in humans we call metabolic bone disease "rickets" which can manifest as a range of deformities from obvious limb deformations to "invisible" deformities of the pelvic canal which makes childbirth difficult. Think of it as a continuum. In snakes, insufficient D3 can manifest as weak or thin eggshells all the way up to kinks that appear in a seemingly "healthy" growing young snake.

As for the dinky-headedness of captive obsoleta, it is unclear exactly how much of this is caused by phenotypic plasticity in head size due to environmental factors such as meal size when the snakes are young and how much of it is caused by D3 deficiency. AFAIK, the exact contributions of each have not been studied. I do know that wild obsoleta hatchlings will eat adult deer mice and adult lizards like green anoles - a far more calcium- and D3-rich diet than most captives get feeding on pinkie and fuzzy lab mice. Adult obsoleta also eat far larger prey than most keepers offer them . . . I've seen 4' adult ratsnakes with 18" long fox squirrels (not counting the tail) in their stomachs - a far larger prey item than the weanling or small rats that most feed them in captivity.

I know (although I don't recall the citation) of at least one study that showed a correlation between prey size eaten and head size in captive obsoleta vs wild obsoleta. I don't recall whether or not that particular study linked this to calcium metabolism or any other biological mechanism. That said, drawing parallels with lizards (MBD) and humans (rickets), as well as inferring from studies of the effect of D3 on snake egg production (particularly with lizard-feeding snakes like kingsnakes), its a pretty safe bet and a good hypothesis that D3 is at least part of the story here as well.
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Kelly Mc
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Re: fox or black rat?

Post by Kelly Mc »

Yes, it is - isnt it :)
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Tim Borski
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Re: fox or black rat?

Post by Tim Borski »

I agree with Black rat. Every dark Fox I've ever seen had the elongated blotches behind the head, this one is plenty light enough to show them if they were present.

Tim
teter247
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Re: fox or black rat?

Post by teter247 »

Leave it to a Hibbitts to end an argument in a single sentence...I havn't seen a Troy post in a long time!!
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muskiemagnet
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Re: fox or black rat?

Post by muskiemagnet »

was told this thing was wild caught by a family when camping. every rat i have seen in the wild had a narrow head. not broad.

like i said, i'll get pics as soon as i can.

-ben
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Don Becker
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Re: fox or black rat?

Post by Don Becker »

As far as coloring goes, ones like that show up in NE Iowa, and I found a couple in central Iowa as well. These three snakes were all found within 10ft of each other within a minute of each other.

Yellowish Black Rat
Image

Reddish Black Rat (it was more red than the picture shows)
Image

Black Black Rat
Image
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Sam Sweet
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Re: fox or black rat?

Post by Sam Sweet »

What Troy and Cole said! Excellent summary of the pinhead effect in CB/CR snakes. I have a pair of Virginia CB Lampropeltis calligaster that were given to me in disgust at age 5 because they still struggled to eat pinkies at 18-20" TL. Eight years later the female is ca. 32", male 28", and they can eat fuzzies but not hopper mice. Nice snakes, but Jeez.
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Kelly Mc
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Re: fox or black rat?

Post by Kelly Mc »

I have a male multifasciata mt king gifted right out of the egg. Tube fed a few times as a neo then went right to pinks. Most of his growth occurred his first year 2011. Hes 27 inches now eating hoppers and has been daycycled with UVB, which he lays out under almost daily.
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Kelly Mc
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Re: fox or black rat?

Post by Kelly Mc »

Snapping off the forelegs of the pinky, fuzzy or hopper makes a big ergonomic difference in how they go down for a lizard eater. There really isnt much of a difference in circumferance factor and fuzzies and hoppers all vary themselves in size, but removing the upward set forelegs really helps.

A lizards arms rest flat laterally, when its dead, and being swallowed by a snake.
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Jon Wedow
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Re: fox or black rat?

Post by Jon Wedow »

Looks like a Black Rat to me. Around here in Ontario we have Fox and Rat snakes overlapping and I have never heard of a hybrid or even seen an adult of one that looks like the other. However as hatchlings they seem to be almost impossible to tell apart (around here anyway). Tim Borski, you have some photos of crazy dark Fox snakes which I have never seen before... are there Black Ratsnakes in that area?

A couple from Southern Ontario:

Image

Image
corey.raimond
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Re: fox or black rat?

Post by corey.raimond »

muskiemagnet wrote:was told this thing was wild caught by a family when camping. every rat i have seen in the wild had a narrow head. not broad.

like i said, i'll get pics as soon as i can.

-ben
Does this person realize that it is illegal to collect black rat snakes (which this is) from Wisconsin?

See http://dnr.wi.gov/files/pdf/pubs/er/er0102.pdf

-Corey
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Tim Borski
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Re: fox or black rat?

Post by Tim Borski »

Tim Borski, you have some photos of crazy dark Fox snakes which I have never seen before... are there Black Ratsnakes in that area?
John, There are no Black rats where I encounter the dark Fox snakes. Here's a dark one and a pic of it alongside a typical individual.


Image


Image


Tim
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muskiemagnet
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Re: fox or black rat?

Post by muskiemagnet »

corey.raimond wrote:
muskiemagnet wrote:was told this thing was wild caught by a family when camping. every rat i have seen in the wild had a narrow head. not broad.

like i said, i'll get pics as soon as i can.

-ben
Does this person realize that it is illegal to collect black rat snakes (which this is) from Wisconsin?

See http://dnr.wi.gov/files/pdf/pubs/er/er0102.pdf

-Corey
corey, he knows. he is a friend who rescues natives and does educational talks. he is licensed by the state to do so.

did you see tim's pics? what if a fox of this "non-normal" color had a "non-normal" white chin as well? your "(which this is)" comment is very patronizing. i am only throwing it out there. that is all. it could be a fox. until we have it in hand we will not know. there are characteristics that make me wonder. just cause you found a few lined snakes does not make you a god. get off your horse. good work though, but honestly, i tried to be your friend and engage you in good conversation but you patronized me then as well. see ya.

-ben
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muskiemagnet
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Re: fox or black rat?

Post by muskiemagnet »

cool snake tim. why don't we do a study and split the fox even more. pantherophis vulpinus tbor. i think muskiemagnet would be a better name for the subspecies though. :D :D :D

-ben
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Tim Borski
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Re: fox or black rat?

Post by Tim Borski »

Ben, P. vulpinas muskiemagnet works for me. 8-)


Tim
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muskiemagnet
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Re: fox or black rat?

Post by muskiemagnet »

don't feel like doing pictures. different head angle. definitely a rat.

-ben
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justinm
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Re: fox or black rat?

Post by justinm »

muskiemagnet wrote:don't feel like doing pictures. different head angle. definitely a rat.

-ben
Ben, I am curious if he's licensed to keep protected species from the wild? I think it's a valid concern. I've seen you get on a high horse as well. It's good that the community polices itself lest we let Authorities do it. I would say no harm in asking.
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Kelly Mc
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Re: fox or black rat?

Post by Kelly Mc »

Muskiemagnet is one of the coolest handles i ever heard. And there are quite a few good ones around here. just sayin.
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muskiemagnet
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Re: fox or black rat?

Post by muskiemagnet »

justinm wrote:
muskiemagnet wrote:don't feel like doing pictures. different head angle. definitely a rat.

-ben
Ben, I am curious if he's licensed to keep protected species from the wild? I think it's a valid concern. I've seen you get on a high horse as well. It's good that the community polices itself lest we let Authorities do it. I would say no harm in asking.
justin. he's licensed. all good.

as far as my high horse. i hope i learned my lessons. i know i can be opinionated. feel free to call me out if needed. thank you.

-ben
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Tim Borski
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Re: fox or black rat?

Post by Tim Borski »

Kelly Mc wrote:Muskiemagnet is one of the coolest handles i ever heard. And there are quite a few good ones around here. just sayin.

+1
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