Blind Snakes and Screech Owls?

Dedicated exclusively to field herping.

Moderator: Scott Waters

Post Reply
User avatar
Mike VanValen
Posts: 2073
Joined: June 7th, 2010, 3:41 pm
Location: Connecticut
Contact:

Blind Snakes and Screech Owls?

Post by Mike VanValen » February 20th, 2014, 5:53 pm

I was looking up info on screech owl nest boxes and came across this paragraph :

Perhaps the oddest part of screech owls' behavior is their association with blind snakes, which have been found in the owls' nests. These odd snakes, which resemble large earthworms, normally appear only at night. Gehlbach and others have observed that the owls bring these small snakes to their nests and release them. The snakes feed on the larval and pupal stages of ants and flies that live in the nest debris, reducing the number of insects competing for the headless mice, dead beetles, and other tidbits cached by the owls. Gehlbach's studies suggest that the snakes actually contribute to the owls' breeding success.

That is pretty damn fascinating, and something I have never heard of.

http://archive.audubonmagazine.org/back ... d0201.html

User avatar
Rich in Reptiles
Posts: 495
Joined: November 30th, 2012, 7:45 am
Location: Missouri

Re: Blind Snakes and Screech Owls?

Post by Rich in Reptiles » February 20th, 2014, 6:03 pm

It is pretty awesome! Have you seen this? http://snakesarelong.blogspot.com/2013/ ... ikely.html

User avatar
klawnskale
Posts: 1211
Joined: June 7th, 2010, 6:09 pm

Re: Blind Snakes and Screech Owls?

Post by klawnskale » February 20th, 2014, 6:15 pm

A wonderful example of domestication. The owls are domesticating the blind snakes to control pests in their nest. The blind snakes benefit by having a good resource of food and live in a protected environment inside the owl nest :thumb:

User avatar
Mike VanValen
Posts: 2073
Joined: June 7th, 2010, 3:41 pm
Location: Connecticut
Contact:

Re: Blind Snakes and Screech Owls?

Post by Mike VanValen » February 20th, 2014, 6:16 pm

No, I didn't see that. Thanks!

User avatar
Lizardman1988
Posts: 235
Joined: June 7th, 2010, 5:38 am
Location: Hays, KS
Contact:

Re: Blind Snakes and Screech Owls?

Post by Lizardman1988 » February 21st, 2014, 11:58 am

klawnskale wrote:A wonderful example of domestication. The owls are domesticating the blind snakes to control pests in their nest. The blind snakes benefit by having a good resource of food and live in a protected environment inside the owl nest :thumb:
How much does the blind snake actually benefit though? While the nest success may be higher for the owls, and the blind snakes may have a ready supply of food, all may not be well. Unless there are more than one bland snakes in a nest, the snakes in the nests will suffer a decrease or complete lack of reproductive fitness. What are the chances of blind snakes reproducing in these nests, or even surviving through winter?

User avatar
klawnskale
Posts: 1211
Joined: June 7th, 2010, 6:09 pm

Re: Blind Snakes and Screech Owls?

Post by klawnskale » February 21st, 2014, 12:09 pm

Lizardman1988 wrote:
klawnskale wrote:A wonderful example of domestication. The owls are domesticating the blind snakes to control pests in their nest. The blind snakes benefit by having a good resource of food and live in a protected environment inside the owl nest :thumb:
How much does the blind snake actually benefit though? While the nest success may be higher for the owls, and the blind snakes may have a ready supply of food, all may not be well. Unless there are more than one bland snakes in a nest, the snakes in the nests will suffer a decrease or complete lack of reproductive fitness. What are the chances of blind snakes reproducing in these nests, or even surviving through winter?
If you read the article in the snakesarelong blogspot, it will answer some of your questions. The researchers found that 14 nestboxes contained anywhere from 1 to 15 blindsnakes; and that the blindsnakes' survival was actually reliant on the presence of baby owls. That fact insures the presence of insects. Blind snakes were only predated on by the baby owls when there was no other available food. The article also states that the blind snakes can climb trees, so if an individual blind snake is starting to find slim pickings, it can leave. It was also documented that a gravid female blind snake did lay her eggs in one nestbox, so supposedly the food source was reliable enough for her to feel stimulated to do that. We are beginning to find out more and more how complex and beneficial interspecies relationships can be; and this is not just symbiosis.

User avatar
Lizardman1988
Posts: 235
Joined: June 7th, 2010, 5:38 am
Location: Hays, KS
Contact:

Re: Blind Snakes and Screech Owls?

Post by Lizardman1988 » February 21st, 2014, 12:47 pm

Well, that answers my questions. Good to know someone looked into it.

User avatar
TravisK
Posts: 772
Joined: July 8th, 2010, 10:14 am
Location: Eastern Washington

Re: Blind Snakes and Screech Owls?

Post by TravisK » February 21st, 2014, 1:22 pm

That is really interesting, you learn something new every day. Thanks for sharing this with us.

User avatar
walk-about
Posts: 567
Joined: June 14th, 2010, 11:04 am
Location: 'God's Country' aka western KY
Contact:

Re: Blind Snakes and Screech Owls?

Post by walk-about » February 21st, 2014, 1:57 pm

This is remarkable!!!

User avatar
Brian Willey
Posts: 100
Joined: June 21st, 2010, 5:32 pm
Location: St. Louis, MO

Re: Blind Snakes and Screech Owls?

Post by Brian Willey » February 21st, 2014, 9:04 pm

Wow, that is fascinating!

User avatar
Daryl Eby
Posts: 963
Joined: June 27th, 2010, 12:27 pm
Location: Terlingua / Marfa, Texas
Contact:

Re: Blind Snakes and Screech Owls?

Post by Daryl Eby » February 21st, 2014, 10:28 pm

Wow.

User avatar
Mark Brown
Posts: 567
Joined: June 8th, 2010, 1:15 am
Location: Austin, TX

Re: Blind Snakes and Screech Owls?

Post by Mark Brown » February 22nd, 2014, 2:02 am

Very interesting. I'll have to keep an eye out around the owl house in my yard.

Image

User avatar
monklet
Posts: 2648
Joined: June 7th, 2010, 3:44 pm
Location: Ventura, CA
Contact:

Re: Blind Snakes and Screech Owls?

Post by monklet » February 22nd, 2014, 8:48 am

:shock: Thanks for posting.
klawnskale wrote:this is not just symbiosis.
I don't get this ...seems a strong case for symbiotic mutualism. ...or, if it's determined that the blind snakes suffer or net no benefit, then a rather odd case of parasitism.

The relationship between some ants and aphids seems very similar and even more complex.
http://insects.about.com/od/coolandunus ... aphids.htm

User avatar
Antonsrkn
Posts: 971
Joined: June 10th, 2010, 1:38 pm
Contact:

Re: Blind Snakes and Screech Owls?

Post by Antonsrkn » February 22nd, 2014, 9:04 am

or, if it's determined that the blind snakes suffer or net no benefit, then a rather odd case of parasitism.
Correct me if I'm wrong but it would only be considered parasitism if the blind snakes suffer, if they gain no benefit that would be commensalism.

User avatar
monklet
Posts: 2648
Joined: June 7th, 2010, 3:44 pm
Location: Ventura, CA
Contact:

Re: Blind Snakes and Screech Owls?

Post by monklet » February 22nd, 2014, 10:03 am

Good point. I think you're right in the case of no suffering and I was aware of that and don't know why I said that :crazyeyes: ...too early in the morning I thinketh. Of course, there'd be no basis for the relationship if the snake was not eating and thus enjoying a gain, albeit perhaps not as optimal as if the snake was not transplanted by the owl.

User avatar
Kelly Mc
Posts: 4315
Joined: October 18th, 2011, 12:03 pm

Re: Blind Snakes and Screech Owls?

Post by Kelly Mc » February 22nd, 2014, 4:26 pm

I wonder if glimpses of the blind snakes in the nest by the young, imprint and begin the habit, of these "belonging" in nest as learned future family behavior?

User avatar
klawnskale
Posts: 1211
Joined: June 7th, 2010, 6:09 pm

Re: Blind Snakes and Screech Owls?

Post by klawnskale » February 24th, 2014, 2:35 pm

Kelly Mc wrote:I wonder if glimpses of the blind snakes in the nest by the young, imprint and begin the habit, of these "belonging" in nest as learned future family behavior?
Good question, Kelly. As someone with a personal interest in avian behaviors, the papers and books I have read are indicating more and more that many avian behaviors once thought to be 'instinctual' are proving otherwise. This especially applies to the rearing of offspring and learning what foods to forage, how to hunt prey, selecting good nesting sites, tool use, etc...On a similar vein to the screech owl/blind snake relationship, blue jays are known to exploit ants by disturbing them to cause them to spray formic acid on their feathers as a form of pest control. Mites and ticks find the formic acid to be very irritating and will fall off the bird's body. Here is an amateur video of someone capturing this behavior in their backyard. Just found out from Wikipedia that this behavior actually has a label: "anting"


User avatar
Kelly Mc
Posts: 4315
Joined: October 18th, 2011, 12:03 pm

Re: Blind Snakes and Screech Owls?

Post by Kelly Mc » February 24th, 2014, 4:02 pm

So fascinating .. Yes I would even be open to the instigation of this and other behaviors turning out to be even more remarkable to conventional assessment. I try not to dismiss the acuities of other organisms, acuities that may be vastly different than my own, and often greater.

User avatar
beemaster
Posts: 112
Joined: November 22nd, 2010, 4:09 pm
Location: SE Massachusetts

Re: Blind Snakes and Screech Owls?

Post by beemaster » February 25th, 2014, 11:08 am

Wow, thanks a lot for sharing that one. Had no idea about this and I'm totally blown away by it. It just seems like such an unlikely pairing.

User avatar
lateralis
Posts: 318
Joined: June 7th, 2010, 8:56 pm
Location: SW USA

Re: Blind Snakes and Screech Owls?

Post by lateralis » February 25th, 2014, 4:02 pm

Burrowing owls are suspected of doing this as well. Several authorities that I know have found blind snakes at the entrance of owl burrows..
Pretty cool stuff

Coluber Constrictor
Posts: 1164
Joined: June 7th, 2010, 6:25 am
Location: Mobile, AL

Re: Blind Snakes and Screech Owls?

Post by Coluber Constrictor » February 25th, 2014, 5:00 pm

I remember reading about this years ago in some kids' book about snakes and thought it was made up. Pretty mind blowing to find out they really do this. :shock: Owls are awesome.

Verhoodled
Posts: 307
Joined: August 7th, 2010, 2:48 pm
Location: Tucson, AZ

Re: Blind Snakes and Screech Owls?

Post by Verhoodled » February 25th, 2014, 10:58 pm

Awesome article. I'd read about this before, but found it fascinating to read the relationship in further detail.

My lone quibble with the article is with the description of blind snakes resembling "large earthworms." An average earthworm dwarfs the largest of blindsnakes by quite a considerable degree.

I see several dozen Leptos per year. Their tiny, speedy, silvery wiggle only catches your eye in the headlights right as you're passing them. A sight otherwise impossible to describe if you haven't seen it while cruising. This wiggler is typical size for AZ.

http://www.youtube.com/watch?v=KZkvA8sX_gE

They can be stupidly impossible to pick up. Best to slip a piece of paper under them. Fingers are often far too fat and clumsy to lift them off the road.

The few monsters of the species I've seen still don't compare to the average earthworms we'd dig from the garden simply to fish for bluegill in ponds back east. As soon as I find one remotely resembling a large earthworm, I'll be calling Guinness, Game & Fish, etc, on a record animal.

User avatar
jonathan
Posts: 3627
Joined: June 7th, 2010, 7:39 am
Contact:

Re: Blind Snakes and Screech Owls?

Post by jonathan » April 23rd, 2014, 2:52 am

I'm having a very hard time imagining the process by which Screech Owls would determine that this was a good idea and do it intentionally (due to them working out the whole survival benefits in their little brains) or instinctually (due to blind snakes in the nest being so helpful that some particular behavior is selected for that caused the owls to fail to kill the blind snakes they catch). In my imagination I guess that perhaps many prey items brought back to the nest are not killed, blind snakes may be able to evade the baby owls and survive in the nest better than other prey items, and the positive benefits of blind snakes in the nest has caused screech owls who are good at catching blind snakes to be selected for.

User avatar
Kelly Mc
Posts: 4315
Joined: October 18th, 2011, 12:03 pm

Re: Blind Snakes and Screech Owls?

Post by Kelly Mc » April 23rd, 2014, 9:34 am

Sometimes I think we need to remind ourselves of our vantage points as bipeds with our versions of vision and hearing. We know this intellectually but it seeps in unconsciously. Things are on a different scale for other organisms.

The phenomenon of imprinting could be more compound than 'balloon as parent ' lab model.

Perhaps imprinting, in natural situ is more complex than we thought. maybe it is as acute as their eyesight.

steve
Posts: 38
Joined: April 9th, 2012, 6:43 pm

Re: Blind Snakes and Screech Owls?

Post by steve » April 23rd, 2014, 12:36 pm

Here is the paper that Originally describe this behavior. Pretty neat little paper. The fledglings grew significantly faster in presence of the snakes than without the snakes.

F. R. Gehlbach and R. S. Baldridge. 1987. Live Blind Snakes (Leptotyphlops dulcis) in Eastern Screech Owl (Otus asio) Nests: A Novel Commensalism. Oecologia, Vol. 71, No. 4. 560-563.

Summary. Eastern screech owls bring live blind snakes to
their nestlings, whereas all other prey are delivered dead.
Some of the snakes are eaten but most live in nest debris,
where they eat soft-bodied insect larvae from the decomposer
community in fecal matter, pellets, and uneaten prey.
Consumption of larvae may reduce larval parasitism on
owl nestlings or larval competition with nestlings for food
stored in the nest, because nestlings with live-in blind snakes
grow faster and experience lower mortality than same-season
broods lacking snakes. We propose a commensalistic
association in which the screech owl benefits reproductively
and the live-in blind snake is not affected.

User avatar
regalringneck
Posts: 562
Joined: June 7th, 2010, 5:20 am

Re: Blind Snakes and Screech Owls?

Post by regalringneck » April 23rd, 2014, 7:53 pm

... dang, i hate to disagree w/ a giant like Gehlbach (one of the original regalis investigators) but i too have a tough time accepting this, the blind snakes that ive held are not going to stay (?) in a hole ... or stick nest; like electricity ... they rapidly "go 2 ground" & dissapear. I'd need to see data ; b-snakes w/ puppae of fly-ant larvae in their stomachs of the same life cycle also fd. in the owls nest ... but how do they get up there? following termite colonys up the rotten trees that attract woodpeckers that make screech owl holes ? ah yes ecology ... the interactions/mutualisms ... beauty : }
Blindsnakes do stink terribly tho., so i dont blame Otis for not eating them, mebbe they "ant" w/ them?
I have seen much wasted prey (including squamates) around various raptor nests, i havent followed the particular caches closely enough tho to see if they are ever actually utilized.

User avatar
Kelly Mc
Posts: 4315
Joined: October 18th, 2011, 12:03 pm

Re: Blind Snakes and Screech Owls?

Post by Kelly Mc » April 23rd, 2014, 10:02 pm

Could the blindsnakes energy needs make them more continual feeders than snakes that feed on more nutritively dense chordate prey?

And could the abundance of feeding opportunity in the nest being a closed system, be a factor of distraction from leaving? Could refuse/matter in it provide some tactile equivalent of fossorial security? Along with the extra warmth in its parameters possibly be a physiological magnet with abundance of close proxy prey? Do they leave often and more are brought?

User avatar
jonathan
Posts: 3627
Joined: June 7th, 2010, 7:39 am
Contact:

Re: Blind Snakes and Screech Owls?

Post by jonathan » April 26th, 2014, 3:17 am

To clarify, the reason I posted what I did is because my intuition is that even if the data (blind snakes being brought back live to nests and thriving within them, thereby helping screech owlet survival rates) is accurate, I think it's highly possible that it may just be a result of factors that have nothing to do with the survival rates.

Blind snakes might just be somewhat harder to kill than other prey (does the owl know where the blind snake's head is?), and taste somewhat worse, and be somewhat better at surviving in the nests, and that combination of facts is coincidentally a nice thing for baby screech owls. But whether or not the snakes or the owls have evolved in such a manner that has increased this advantage is something I would lean towards a "probably not".

The main questions, I think, are

"Would this behavior have begun and continued even if the blind snakes didn't help the chick survival rates?"

and

"If either the snakes or the owls evolved to take advantage of this relationship, what were the actual traits that were selected for?"

User avatar
Kelly Mc
Posts: 4315
Joined: October 18th, 2011, 12:03 pm

Re: Blind Snakes and Screech Owls?

Post by Kelly Mc » April 26th, 2014, 8:40 am

You bring up an interesting point, as broader ranges of behavior, than the traditional definition and values of benefit, are being examined and enlarging our understanding of animal behavior, in the sciences.

along with rapidly expanding technologies enabling us to get a closer look at how brains and behavior actually work.

Neural mapping and behavioral research have come a Long Way since the wire mother and electrodes of the past, correlating with a crude analogy of brain "areas". but that's whole other (exciting) topic .

Its all exciting though.

User avatar
Joseph S.
Posts: 540
Joined: June 11th, 2010, 4:21 pm

Re: Blind Snakes and Screech Owls?

Post by Joseph S. » April 26th, 2014, 11:08 am

It does seem like this is a partnership in the beginning stages. Indeed-originally started by screech owls probably dropping blindsnakes by accident somehow and failing to kill them.

One would have to look at out of season consumption of blind snakes by screech owls and determine if both sexes bring back blind snakes with equal frequency. Also, seeing what nesting/ young rearing stages they are brought back the most, if the number of blindsnakes captured is correlated to owl nest parasite load, etc. etc. A clincher would be if they are being brought back during incubation, for example.

A lot of neat behavioral study could be done with this.

Now we need to give it another 1000 years and blindsnakes will develop some sort of signal behavior by rubbing their scales together that will provide an auditory signal for owls to locate them and drop them into nests for free meals...(although for the time being I suspect this is a weird form of parasitism since the blind snakes are injured, sometimes consumed, and displaced from their home range so the fitness of captured blindsnakes is probably lowered)

Post Reply