Reptile & Amphibian Forums

Interesting find, these 2 snakes in the situation they were in...roadkill? Direct predation? Why of all possible prey items [one of the parents was observed feeding on a small mammal on top of a nearby saguaro...] were these 2 related taxons lost/discarded?
Ah the inherant problems w/ a data set of 1.....
Wish'd I'd proofed my txt box a bit closer!
TC; beautiful green snake down below...& I hope you collect a limit of those blues

John,
My two younger son's and daughter along with their mother came across two ravens in the process of killing a Rubber Boa on a back road in Mendocino county, California in the early 1980s.

On May 2nd, I found an adult male and female boa about 30 meters apart under rocks at my eastern Oregon site that had large wounds on the low part of their bodies. There were no teeth marks around these recent gaping wounds in which part of the lower intestine of both boas were exposed outside the body.

The only explanation I could come up with is that one or more Ravens, common and nesting at that site, had found the two boas (on the surface in courtship) and caused the wounds and somehow both snakes had escaped. They both died a few days later. They soon will be donated to the Calif. Academy of Science for voucher specimens. Was a real shame as the female was one of the largest I had found at that site (over 25" and palped 5 - 6 ova.

Richard F. Hoyer

Hello Richard, uuugggh the thought of a raven boinking & tearing at one of the most fragile & docile serpents is enough to make me sick! Tho its still interesting!
I feel less guilty now for [in my more lethal youth] putting a handful of them or 2 in the big 50mm scope on my .222 & sending them on as a puff of feathers!
Ive watched ravens for cummulatively hours on hundreds of occasions & never observed them w/ a snake...might make for an interesting lit-review...thus your Mendocino report is particularly interesting to me. Your May 2 find while fascinating, disturbing & puzzling... doesnt in my mind implicate ravens w/o additional evidence. Together your observations w/photos of the wounds might make a decent field note in Herp Review?
I also cant recall them paying any attention to roadkilled serpents & have long noted the squirrels/rabbits/etc are scavenged much faster by ravens & mammalian scavengers than are your typical DoR snakes...Turkey & black vultures now.....those are a whole nother story...

Cheers, RxR

Posted by: Richard F. Hoyer at Sun May 15 20:33:06 2005 [ Report Abuse ] [ Email Message ]

John,
My two younger son's and daughter along with their mother came across two ravens in the process of killing a Rubber Boa on a back road in Mendocino county, California in the early 1980s.

On May 2nd, I found an adult male and female boa about 30 meters apart under rocks at my eastern Oregon site that had large wounds on the low part of their bodies. There were no teeth marks around these recent gaping wounds in which part of the lower intestine of both boas were exposed outside the body.

The only explanation I could come up with is that one or more Ravens, common and nesting at that site, had found the two boas (on the surface in courtship) and caused the wounds and somehow both snakes had escaped. They both died a few days later. They soon will be donated to the Calif. Academy of Science for voucher specimens. Was a real shame as the female was one of the largest I had found at that site (over 25" and palped 5 - 6 ova.

Richard F. Hoyer

Just my $.02 here but perhaps the reason the snakes were killed and not preyed upon is because the raven's were simply defending a nest? I've seen magpies (this is in another country) practically disassemble a cat that got too close to a nest on more than one occasion! Grisly, but all part of the natural plan I suppose.

:O)

Bryan
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"Nothing happens in contradiction to nature, only to what we know of it."

Here on the desert ravens definitely scavange road-killed snakes in the early morning, provided that they are not already flattened into the road-bed. And, of course, they are notorious for preying on hatchling desert tortoises.
We have been tracking raven populations from bird censuses over some 40 years, and the graph curve looks like the curve on human population growth (near exponential).
What was once a rare bird on the desert is now extremely common.

Glad to see a few giving it a thought...

Defending the nest is definitely thinking out of the box...& on smaller passerines; nest predation via ophidians is a big issue...but to know ravens & magpies [] is to know small colubrids are not a nest predation issue for them!
Harold, while I cant say I never saw a raven on a DoR snake...I can recall them nearly daily on mammalian, avian, or even saurian roadkill & again why.... out of a mole of ravens....have I never seen one flying w/ a snake????
Clearly RH has witnessed live predation..see above.
Now heres a desertrat challenge...who has seen a raven actually drink?
Managed to tree a Son. whipsnake today...what an arboreal spps!
Ill have to see after download...if any are worth posting!

Cheers/RxR

I suppose I have more opportunity, seeing ravens on a daily basis. They don't seem to pick up and fly with snakes big enough to see. They pick at them on the pavement, and if you drive by they fly up and then return.
Ravens come down to drink at my irrigation all the time. So I see them drink all the time, at least if I see them before they see me. They are very wary birds on the ground.

Hi All,
Speaking of predation on snakes and scavenging, Sunday I was in the Big Bend area of Florida and saw examples of both. I saw a broadwing hawk fly accross the road with a small(15 in) snake and then saw a turkey vulture scavenging on a snake and backed up to ID it. It was a 6 in chunk of an about 5 ft."white oak" phase grey rat and as I drove off, a fish crow flew down and grabbed the remains and flew off. I know the birds make short work of road kills both in FL and W. TX.
Jim McLean

You know, I did give some thought to the size differential but I considered that (perhaps) ravens are just "hardwired" to defend thier nests to anything that resembles a threat. Perhaps those with more experience with ravens can shed some light on that.
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"Nothing happens in contradiction to nature, only to what we know of it."