text:
Talk:Agkistrodon piscivorus

Maps
I've found a source for wikipedia usable maps (http://www.lib.utexas.edu/maps/united_states.html) and I'll start stitching together the census line maps to produce a US map to use for species ranges.

These maps have been used on some pages already (which is how I found them). See Arlington County, Virginia for an example.

— Preceding unsigned comment added by 68.86.218.135 (talk) 14 December 2003 (UTC)

I don't know how far you've gotten on this, but I found some good PDF maps at the US Census Bureau, which are public domain. I cleaned up one of them to show state and county borders; no rivers and lakes, unfortunately, but it's a nice high resolution. Check it out. -- Wapcaplet 22:10, 20 Dec 2003 (UTC)

Copperhead?
I'm no herpetologist or anything, but isn't that snake to the left of the description a copperhead? — Preceding unsigned comment added by 68.217.126.75 (talk) 02:20, 31 May 2007 (UTC)

 * No, I'm pretty sure that's a young cottonmouth. As juveniles these two species are very much alike, but according to Conant (1975), the main difference is that young cottonmouths have a dark postocular stripe (a line on the side of the head that descends from behind the eye to the angle of the jaw) and young copperheads do not. In the picture, you can just see a postocular stripe on the left side of the animal's head. --Jwinius 10:56, 31 May 2007 (UTC)

 * It's a cottonmouth. The young look very similar to ccopperheads, leading a lot of people to believe that coppers live in areas where they don't (like South Florida). Lfishel 05:23, 2 June 2007 (UTC)

 * This is true. These animals, in their youth, can look a *lot* like their smaller relative, the copperhead (_Agkistrodon contortrix_).  The Southern Copperhead, _A. c. contortrix_, only ranges into a teeny bit of northern Florida, but I've known people in counties where copperheads aren't known to occur who have insisted that they had seen them there; invariably it turns out that the snake they saw was either a young cottonmouth or a colubrid (usually a watersnake of the genus _Nerodia_; I think these feisty but harmless animals may be responsible for the cottonmouth's reputation for aggression, since my impression has been that cottonmouths are shy, mellow snakes, reluctant to strike unless they've tried every other self-defence technique at their disposal, and not aggressive in the slightest).

 * One easy way to tell that a pitviper of the genus _Agkistrodon_ (copperheads, cottonmouths, cantils) is a juvenile is by the almost fluorescent greenish-yellow tail tip (about the colour of a tennis ball), used by the young snakes in caudal luring; if you're in Florida and you see a juvenile pitviper, consider the likelihood that it is a cottonmouth (the southern limit of the copperhead's confirmed range is Liberty County). Copperheads' colouration is typically more tan, sometimes even yellowish, although it may be reddish -- it evolved to blend in with leaf litter -- while newborn cottonmouths tend either to be very bright reddish-orange, or have a very pale background colour, sometimes with a pinkish tint (as in the picture) and dark brown or reddish-brown markings; they darken as they get older, so that the pattern on an adult cottonmouth may be barely visible (particularly among the Western race).  Also, the Southern Copperhead (the subspecies that just barely enters Florida) usually just has saddle-shaped markings, often narrower than those of the Northern subspecies -- sometimes they actually don't meet in the middle, instead forming triangles on the snake's sides; juvenile cottonmouths usually have spots on the inside of and in between the bands, more like the markings typical of the Northern Copperhead (if anything the young cottonmouth's markings are more ornate than those of a Northern Copperhead).  Note, however, that in the northern part of the cottonmouth's range, in the Carolinas and southeastern Virginia, the copperheads may be the Northern race (_A. c. mokasen_) or Northern-Southern intergrades, and may have some of the more elaborate patterning typical of the Northern race.

 * The two southwesternmost-ranging subspecies of copperheads, the Broad-Banded (_A. c. laticauda_) and Trans-Pecos (_A. c. pictigaster_) Copperheads, who reside in central and western Texas and Oklahoma, are easier to tell apart from young cottonmouths; these copperheads tend to be darker -- sometimes a very dark grey -- as juveniles, and instead of the saddle-shaped markings typical of the other races of copperheads, they have straight, wide bands (as suggested by the common name and species epithet of the former).

 * Cottonmouths may be identified easily if they choose to exercise their eponymous warning display, since the lining of a copperhead's (or a watersnake's) mouth is pink (about the same as a human's). There are other vipers and pitvipers whose mouths are white or pale pink on the inside (such as the Eyelash Palm Pitviper, _Bothriechis schlegelii_, of Mesoamerica), but none whose ranges overlap with that of the cottonmouth, that I am aware of.  Mia229 (talk) 11:27, 12 September 2011 (UTC)

Cottonmouths in trees...
Young cottonmouths are occasionally seen in low bushes and I can't rule out one climbing a tree now and then, but certainly 99.9% of the "cottonmouths" seen basking in tree branches over water are harmless banded watersnakes (nerodia fasciata) or related species, the snakes most commonly mistaken for cottonmouths... I'm not sure what would constitute verification of this, since there are no doubt hundreds of people who swear they've seen it and the fact that no herpetologist or serious snake keeper has ever witnessed it and no one has ever taken a picture doesn't "prove" that it didn't happen. 65.218.191.140 21:08, 28 April 2006 (UTC)

no they have not proved!! — Preceding unsigned comment added by 71.192.221.195 (talk) 00:11, 9 June 2006 (UTC)

 * While it would be impossible to tell without catching and handling the snake (something i wouldn't do if i thought it was a cotton mouth) I'm 99% sure I've seen at least one drop from a tree branch right in front of me. It was dark with the correct colorations, very thick for it's length, and had the typical viper shaped head.  It also swam across the top of the water like a cotton mouth.  If it walks like a duck, looks like a duck, and quacks like a duck, it's probably a duck.  I can also back-up the claim that they're not nearly as aggressive as people make them out to be.  I've had friends pick up 4' cotton mouths with snake hook and we had to provoke it just to see the characteristic open mouth.  —Preceding unsigned comment added by 167.7.17.3 (talk) 18:02, 17 October 2008 (UTC)

 * If you happen to witness such a thing again, take a photo with your cell phone! Mia229 (talk) 16:08, 13 September 2011 (UTC)

Yes, Agkistrodon piscivorus does bask in tree branches. In the 1970s I was participating in field work in Alabama and Mississippi, studying turtles of the genus Graptemys in the river systems there. I and two other herpetologists were in a johnboat, checking turtle traps, when we brushed against some tree branches which were hanging low over the water. A large snake was dislodged from the branches and fell right into the boat. All three of us positively identified it as an adult A. piscivorus. Lyttle-Wight (talk) 02:28, 10 April 2019 (UTC)

Here is a photo from wiki-commons showing two cottonmouths in a tree with a third watersnake. It is not unusual. I have seen them on a few occasions two or three feet up in bushes and trees, over water and dry ground.WiLaFa (talk) 05:31, 10 July 2021 (UTC)

Range should mention Mississippi
One other thing, these snakes are located in Mississippi, as well. I do not know why that state did not get mentioned. — Preceding unsigned comment added by 65.15.103.159 (talk) 20:14, 21 September 2006 (UTC)

Request: swimming picture of non-venomous watersnake
This page could benefit from a picture of a non-venomous watersnake swimming. Then readers could see the diference in how they swim, as this is a key way of distinguishing between cottonmouths and other watersnakes.JeffStickney 13:11, 15 October 2006 (UTC)

 * The article doesn't seem to include a picture of a swimming Cottonmouth either! Anyway, I have a picture I took in Nashville, TN (on the Harpeth river) in 2006. I was later told it was a Cottonmouth, although from this article, Nashville would be outside of the snake's natural range?
 * If it is indeed a Cottonmouth, perhaps we can include it as such. If it is a different and non-venomous watersnake, that would satisfy the original request!
 * (Not sure why the file is not embedding, so here's a link to the Wikimedia page.) --Chinmay7 (talk) 09:20, 28 September 2009 (UTC)
 * I included it in the article and have displayed it at right of these comments. That looks like a cottonmouth to me. — BarrelProof (talk) 00:58, 10 July 2021 (UTC)

Copperhead as a common name
Are we sure that Copperhead is a common name for a Cottonmouth? I'm pretty sure it's not. —Preceding unsigned comment added by Jonjuan (talk • contribs) 17:22, August 29, 2007 (UTC)

 * According to Wright & Wright (1957), "copperhead" was at one point or another a common name used by some people to refer to A. piscivorus. That this name is usually used to refer to A. contortrix is beside the point. However, it is a good example of how confusing common names can be. --Jwinius 17:38, 29 August 2007 (UTC)

I live in the SouthEast (of North America) - in the area it's pretty common knowledge that we have three types of poisonous snakes: Rattlesnake, copperhead, and the water moccasin (aka cottonmouth). I would agree that there might be people that confuse two snakes (everyone gets the rattlesnake right), but I find it highly confusing to think that the three poisonous types of snakes are Rattlesnake, copperhead, and copperhead. Msull (talk) 03:33, 8 July 2008 (UTC)

 * Common names often refer to more than one species. It may be that A. piscivorus is generally referred to as the cottonmouth and that A. contortrix is generally referred to as the copperhead, but the point is that this is not always (or has not always been) the case. The list of common names here is simply as complete as I can make it given the available literature. I didn't make any of this stuff up: that's just the way it is. If you don't like it, go somewhere else. --Jwinius (talk) 10:16, 8 July 2008 (UTC)

 * There's no need to go somewhere else, maybe you could use more recent literature instead of studies from the early 20th century. There comes a point when it's more important to include correct information over cited information.  Anyone who's written that the cottonmouth is also called a copperhead was misinformed, as the two snakes share the same range.  It's not like when different regions used the same common name for two species, these two snakes share the same range so it would be incorrect to call both snakes which are found in the same place, the same name.  Even Linneus mislabeled specimens, I would not put it past the author of the source you're referencing -- and it's not like you have to include it if there's doubt to it's authenticity. — Preceding unsigned comment added by 167.7.17.3 (talk) 18:08, 17 October 2008 (UTC)

 * When it comes to common names, there is no right and wrong. As opposed to scientific names, there is no governing body, such as the ICZN or ICBN that can vouch for their uniqueness, and there are no taxonomic authorities and can say whether they are currently valid or not. The only exception to this rule that I know of is the AOU that regulates common names for birds in North America. So, if in some old publications on snakes certain authors refer to this species as a copperhead, then there is no choice but to accept that as a fact. Just as important, if we add information from a source, such as Wright and Wright (1957), but leave out certain items just because we don't agree with them, then we are being selective with the truth, which is just as bad as corrupting it. --Jwinius (talk) 23:07, 18 October 2008 (UTC)

Water moccasins
what can i do to get rid of water moccasins? how can i tell if it is indeed a baby water moccasins or not? please let me know it's very important, due to the fact that i've done killed two in my house and i have a 3 yr old son. —Preceding unsigned comment added by 24.155.163.109 (talk) 22:10, 9 October 2008 (UTC)

 * Call an exterminator!! Though they probably won't attack unless provoked I wouldn't take my chances!  —Preceding unsigned comment added by 167.7.17.3 (talk) 18:10, 17 October 2008 (UTC)

 * Read the article. Most likely the snakes that you have encountered are not water moccasins at all and are probably harmless. --Jwinius (talk) 23:09, 18 October 2008 (UTC)

 * First of all, may I ask exactly where you live? I ask because I've known many people who thought they had encountered cottonmouths in locations that were outside the range of these snakes (including one in New England!).  According to reverse lookup you are in central Texas, which is the westernmost edge of the cottonmouth's range, but if you are willing to tell me what specific metro area you live in I can probably find out whether there are cottonmouths there.
 * Wildlife rehabilitation (a volunteer service which should be listed in the phone book) should be able to identify whether they are cottonmouths or not. If the snakes are indeed cottonmouths, check under "wildlife" or "animal;" there should be a local service that can relocate them safely and humanely; these are more likely to have experience with snakes than an exterminator.  I should mention that the cottonmouth that is dangerous is the one you don't see, and if you've seen them on your property, the chances are that you will continue to encounter them.  You should be careful to watch where you step, and don't reach somewhere you can't see (like in a tree hollow, behind a rock, in deep grass, etc.); teach your child to be careful as well, and not to disturb a snake or approach it too closely (staying five feet away will be more than sufficient).  Cottonmouths are not aggressive and will not attack a human unprovoked; even if they feel threatened, they are unlikely to strike without first trying other tactics such as crawling away, gaping, or spraying musk.
 * I strongly recommend you not try to kill or remove cottonmouths or other venomous snakes yourself. A very large percentage of the venomous snake bites in the US are the result of people (usually young men) trying to catch or kill a snake (I've seen various statistics, between 40% and 90%, but it's definitely a lot).  If you are finding snakes inside your house, there is a high likelihood that you have a rodent problem; dealing with this should cause the snakes to lose interest.
 * Here is an article about snakebite by Prof. Whit Gibbons, an experienced herpetologist at the University of Georgia's Savanna River Ecology Lab: http://www.uga.edu/srel/ecoviews/ecoview020909.htm
 * — Preceding unsigned comment added by Mia229 (talk • contribs) 16:08, 13 September 2011 (UTC)

'rattler'?
Has anyone ever heard of these snakes being referred to as rattlers? Maybe by someone who calls all venomous snakes rattlers, but as these snakes have no rattle and have no audible warning, outside of hissing, I don't believe this is a common name for these snakes. —Preceding unsigned comment added by Eaglescout1984 (talk • contribs) 16:45, 3 June 2009 (UTC)

 * My understanding is that this term comes from the cottonmouth's habit of vibrating its tail when agitated--a trait shared with other poisonous and non-poisonous snakes. In shallow water, this in turn agitates the water or in leaves or other debris it makes a rustling sound.  Pinethicket (talk) 12:59, 28 September 2009 (UTC)

 * Juvenile cottonmouths and copperheads also wiggle their tails i
 * According to Campbell & Lamar's _Venomous Snakes of the Western Hemisphere_, cottonmouths are or at one point were sometimes called "water rattlesnake," "mangrove rattler," or "saltwater rattler." I don't know if any of these names are still used.  Pinethicket is right, they can make noise by wiggling their tails in water or leaf litter.
 * Mia229 (talk) 16:08, 13 September 2011 (UTC)

Geographic range
The geographic range map show these snakes existing right up to the very edge of the border of the state of Kansas, but I am quite sure they do exist in that state, as my best friend grew up with a boy who was killed by multiple bites from these snakes (upon diving into a water-filled rock quarry), in approximately 1980. There is no other species of aquatic or semi-aquatic, venomous snake in the continental United States, so it had to be this snake. KevinOKeeffe (talk) 05:09, 19 June 2009 (UTC)

The geographic range map shows that these snakes stop in southern Missouri, however they are found in just about every pond, lake, river, and creek up here in northeastern Missouri as well. They are all over up and down the Mississippi and Missouri rivers, so its likely they are found in any state these 2 rivers run through. So I think its safe to say the current map is quit a bit off. —Preceding unsigned comment added by Ryu80x (talk • contribs) 03:43, 11 October 2010 (UTC)

 * I agree. When visiting my grandmother in Southwest Iowa, I saw a cottonmouth while fishing in the East Nishnabotna River. I am certain it was a cottonmouth. I can differentiate between cottonmouths and watersnakes. 2604:CB00:20B:CC00:61C6:8199:83EA:35B (talk) 05:56, 10 October 2020 (UTC)

I agree the map is too limited. I grew up in an area of metropolitan Atlanta that would be excluded from this map (at the time in a relatively undeveloped marshy suburb, now a concrete jungle), but had multiple run-ins with cottonmouths. I can also factually (though anecdotally) state that cottonmouths are, at least at times, quite deserving of their aggressive reputation. I was 'chased' (forced to back away very quickly and followed by a threatening snake) on two occasions. Taterbill (talk) 15:15, 20 August 2011 (UTC)

Toxicity of venom
First sentence makes an assertion that the venom can be sometimes fatal. According to http://emedicine.medscape.com/article/771329-overview, at least one fatality has been reported, so this might make a good citation for that statement. —Preceding unsigned comment added by 69.127.23.158 (talk) 23:48, 19 July 2009 (UTC)

Introduction - reference to "approaching" intruders
It is common or tribal or pseudo knowledge that Cotton Mouths are aggressive. "Urban" (the term doesn't seem to quite fit here) legends have it that these snakes will approach and attempt to enter boats and have "chased" people and dogs.

The article does not really weigh in heavily on this issue, but does refer to the animals "approaching" intruders. The nearest citation to this statement, however, does not mention such behavior.

Given the variety of beliefs and statements on this aspect of Water Moccasin behavior, it would be helpful to strengthen this part of the article.

Pondhockey (talk) 05:42, 10 July 2010 (UTC) (Pardon my clumsiness and possible ignorance of etiquette; I'm new to this kind of discussion and editing.)

Aggressiveness
Here we go again! How about some unbiased writing not giving undue weight to a single study!

One study in 2002 found few snakes in the experiment to exhibit aggressive behaviors as defined by the researchers. That is NOT a finding that the water moccassin is not aggressive!

Did they test the aggressivenss near the nest or with young? Did they test while feeding or preparing to feed? Did they test in all seasons? Did they test both in the water and out of the water? Were they confirming prior studies or was this the first -still not duplicated- study? Furthermore, one sub-species could be more aggressive than others, but again, we just don't know, do we?

Not only that, the behavior reported by the study was different in repeated tests, with most snakes trying to escape in one study; and with most snakes adopting a defensive threat posture in another test!. What can really be concluded from this?

We also suffer from the inability to review the full text -freely- in order to evaluate -and criticize- the methodology. The bottom line is, Wikiteurs should not cite studies unless they cite reviews and not original research, which by definition is not yet the established body of knowledge -remember cold fusion?-

Clearly the wikiteurs have no clue about the scientific process to find the truth, as always evolving process. The paragraph should state instead that it is not settled whether the snake is aggressive and then cite representative studies or reports from both sides. This is what you do until a study is duplicated by others under the same conditions. Then you can conclude that, given the same conditions, i.e. temperature, humidity, lighting, season, maturity, etc., etc., what was reported can be generally accepted. Wikipedia is NOT a *Real* encyclopedia!

Disclaimer: This is a critique of a specific paragraph, not the whole article! 146.23.68.40 (talk) 23:44, 25 February 2011 (UTC)

Completely agree. See my anecdotal post under Geographic Range above. *Something* can make them display aggressive behavior. Taterbill (talk) 15:17, 20 August 2011 (UTC)

Contradiction?
"Harmless watersnakes of the genus Nerodia are often mistaken for it. These are also semiaquatic, thick-bodied snakes with large heads that can be aggressive when provoked,[5] but they behave differently. For example, watersnakes usually flee quickly into the water, while A. piscivorus often stands its ground with its threat display. In addition, watersnakes do not vibrate their tails when excited.[18] A. piscivorus usually holds its head at an angle of about 45° when swimming or crawling.[5]"

But it says earlier in the aggressiveness section that water moccasins usually swim away. What is the deal? Do they stand their ground or do they swim away? — Preceding unsigned comment added by Transkar (talk • contribs) 20:42, 27 April 2011 (UTC)

Latin words
Re:
 * The specific name is derived from the Latin words piscis and voro, which mean "fish" and "to eat".

Doesn't voro mean "I eat"? Paramecium13 (talk) 22:04, 4 July 2011 (UTC)

 * Technically "voro" can be either the first-person or stem form of the verb; you're right, it's not the infinitive ("vorare" is). "Piscivorus" is usually translated "fish-eater" [n.] or "fish-eating" [adj.]. — Preceding unsigned comment added by Mia229 (talk • contribs) 16:08, 13 September 2011 (UTC)

 * Nothing takes up as much space on WP as amateur translations of foreign words. Keep it short and sweet! 46.94.151.134 (talk) 21:01, 9 October 2020 (UTC)

Agression in this species (Agkistrodon piscivorus)
I am disturbed by this notation:

"Although their aggression has been exaggerated, on rare occasions territorial males will approach intruders in an aggressive manner" [3] epa.gov Wharton, C.H. 1969. The cottonmouth mocassin on Sea Horse Key, Florida. Bull. Florida St. Mus., Biol. Sci. 14:227-272.

I would question this completely. Perhaps there needs to be clarification... My belief is that there needs to be a distinction between aggressive behavior on land or in the water.

I understand that anecdotes are forbidden in wikipedia archives... therefore I would leave it up to someone to research this and actually determine the aggressive nature of these snakes... but I would caution the EPA's statement that aggression "has been exaggerated". What exactly does it mean when something has been exaggerated? Is the EPA taking anecdotes and dismissing the aggression completely? That is certainly what the tone of the sentence is.

If anything, I would recommend that the statement from the EPA be scrapped completely unless an aggression study is actually done. From my own anecdote which occurred not even 20 minutes ago August 14, 2011 @ approximately 10:45 AM CST, I can tell you that cottonmouths are extremely aggressive on land. I wish I had made a video to record the "attack first" disposition of this particular cottonmouth... For the record, I live in Denton County Texas, next to lake Lewisville... to give some kind of geographical perspective... who knows... there are so many sleight variations of species based on location, it could be that the species in Florida is more "docile".

I am inclined to think, however, that there is a distinction between aggression on land versus water... the droughts here in TX means that cottonmouths probably have less water to reside; therefore they are forced onto land more frequently. There might be a connection between mobility and aggressive behavior. They are adept at moving in the water, but what about land? There may be a natural tendency for "fight" due to the fact that the land, for this species, is "unsafe" territory.

 * The Florida Cottonmouth (_A. p. conanti_) is a different subspecies than the Western Cottonmouth (_A. p. leucostoma_), which ranges as far as eastern Texas. It's possible there are differences in behaviour.  Cottonmouths are semi-aquatic; they're as mobile on land as other pitvipers such as the copperhead, so I don't think that's it, but it may be that other adaptations for water (such as a preference for aquatic prey, although the species is also known for being willing to eat almost anything) make them more comfortable there and so the drought is leading to increased desperation to flee.  It is true that the species is almost always found in or near water. Mia229 (talk) 16:31, 13 September 2011 (UTC)

UPDATE:

I found this article regarding the aggressive behavior of the cottonmouth... Here is the citation:

<ref>

This is a great article and explains exactly what happened with me and the cottonmouth I encountered. Dr. Means is calling this "blocked flight aggressive" behavior. An excellent article on the aggressive nature of this snake and other snakes. It's a great find.

— Preceding unsigned comment added by Blaine72 (talk • contribs) 16:32, 14 August 2011 (UTC)

 * Yes, I remember this report; Dr. Means refers to the behaviour as "shammed aggression," or "bluffing aggression," since the intent is clearly defensive and in any case is hardly unprovoked. (If I were the snake, I would certainly consider preventing me from escaping a provocation, especially if the one doing the blocking is a big scary human-monster. :->)

 * It's rare to happen upon a cottonmouth with her babies, as the young pitvipers only stay with their mother for a short time (about 2 weeks max). Mothers of other species of pitvipers, and other viviparous snakes such as boa constrictors, have been known to cover for their newborns by making false strikes while the young retreat to safety (up a tree, into a burrow, etc.), though.  (I don't know whether any oviparous snakes do this too, although I would expect it at least in the case of oviparous pitvipers such as the bushmasters (_Lachesis_) and Malayan pitviper (_Calloselasma rhodostoma_), and perhaps pythons (which also brood their eggs).

 * I would say the EPA is correct that aggression "has been exaggerated," although I agree that this statement is rather ambiguous; I'm dubious as to whether this bluffing behaviour (which is, as Dr. Means makes clear, *not* an actual attempt to bite) even ought to be considered "aggression," but even if it is, Dr. Means seems to be right that it only occurs under particular circumstances, does not appear to pose any threat of a bite, and probably can be avoided simply by letting the cottonmouth go on its way rather than blocking it. The rumoured "aggression" by cottonmouths is, in any case, much more extensive than that which has been documented reliably.  The EPA didn't rule out aggression, though, they just said that rumours have exaggerated it.  Mia229 (talk) 16:08, 13 September 2011 (UTC)
 * I cannot personally attest to the aggression... but my late wife was, as a pre-teen, chased over a dozen yards by one.
 * Wait. No. Yes, I can, but I'd actually forgotten. My brothers and I once had to scramble into the back of a pickup to get away from a nest of them, and then I had to get in the front seat without getting into their reach to drive us away (I was the only one who knew how to drive the pickup, at 13). I've never seen nor heard of so many together before or since, but I'd forgotten it, given that it was almost forty years ago. Frankly, I never want to. Dstar3k (talk) 10:01, 6 October 2023 (UTC)

Poisonous?
Question: Is this snake poisonous? — Preceding unsigned comment added by 1.120.97.183 (talk) 03:52, 25 April 2015 (UTC)
 * No, but it is venomous. — BarrelProof (talk) 10:35, 8 July 2021 (UTC)

Taxonomic changes
Hi all, The taxonomy of this complex was recently revised.

Two species and no subspecies are now recognized. Agkistrodon conanti on the SE coastal plain in Florida and Agkistrodon piscivorus everywhere else with gene flow between species. While exciting, this isn't an unexpected development and these biogeographic patterns have been well described in the literature and served as key examples in Avise's work that founded the field of phylogeography.

Link to full text: http://cnah.org/pdf/88290.pdf - this includes maps, niches and putative hybrid zones for both this species and its congeners, Agkistrodon contortrix and Agkistrodon laticinctus. The Society for the Study of Reptiles and Amphibians, as well as the new Peterson Field Guide to ENA snakes accept these changes and they should be incorporated into wikipedia at (y)our earliest convenience. Phylogenizer (talk) 20:39, 31 March 2017 (UTC)Phylogenizer — Preceding unsigned comment added by Phylogenizer (talk • contribs) 20:36, 31 March 2017 (UTC)

External links modified
Hello fellow Wikipedians,

I have just modified one external link on Agkistrodon piscivorus. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
 * Added archive https://web.archive.org/web/20051121020750/http://www.uga.edu/srel/Reprint/2583.htm to http://www.uga.edu/srel/Reprint/2583.htm

When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.

Cheers.— InternetArchiveBot  (Report bug) 18:09, 10 December 2017 (UTC)

Feeding Behavior
I feel this long list would be better presented in some kind of table format. Right now, it's far too cluttered to be readable. — Preceding unsigned comment added by RJ0053 (talk • contribs) 15:00, 14 September 2018 (UTC)

How is this a good article?
I’m curious as to how this page meets good article criteria when I have observed at least 3 citation needed tags throughout? — Preceding unsigned comment added by 2601:84:8880:5E80:CDF9:B68A:D461:E08F (talk) 05:56, 8 February 2020 (UTC)

It is outdated as well. The taxonomy has been changed so the former species was split into two. The rangemaps are now wrong and the picture in the header appears to be A. contanti, not A. piscivorus. More info can be found at https://doi.org/10.1111/zoj.12211 and Peterson's 4th Edition Field Guide to Reptiles and Amphibians of Eastern and Central North America (2016). I am not very familiar with Wikipedia yet, so I don't really feel comfortable updating it myself, but I hope someone addresses it. SilverSheWolf (talk) 03:39, 29 July 2020 (UTC)

Number of Venomous Snakes
The article say that there are only four venomous snakes in North America. I can name off the top of my head more than four species of venomous snakes that I have seen just in the states of Arkansas and Missouri where I have lived. Copperheads, Pygmy Rattlesnake, Canebreak Rattlesnake, Diamond Back Rattlesnake, and Cottonmouths. All of those species I have seen in the wild in North America. That is more than four. 2604:CB00:20B:CC00:61C6:8199:83EA:35B (talk) 05:24, 10 October 2020 (UTC)

 * I read the article referenced and it is wrong. I assumed that the correct statement would be that there are only four genera of venomous snake in North America (that might be correct, but I'm not sure), but that's not the intended statement of the author of the referenced article. The author lists the "only four snakes" of North America as Cottonmouth, Rattlesnake, Copperhead, and Coral Snake. There are several (wiki says 36) species of rattlesnakes in two genera that the author sites as just one snake species and the copperhead is a close relative of the cottonmouth in the same genus. 2604:CB00:20B:CC00:61C6:8199:83EA:35B (talk) 05:47, 10 October 2020 (UTC)

Name change
I don’t like the fact that the article is named Agkistrodon piscivorus, Because most Wikipedia articles used the species common name. Quincy43425 (talk) 23:07, 28 February 2021 (UTC)

Requested move 8 July 2021

 * The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review after discussing it on the closer's talk page. No further edits should be made to this discussion.

The result of the move request was: Not moved. New evidence has been presented that the proposed name is not precise enough, the original Cottonmouth species having been split in two. Opponents also point out that there is no pressing reason to move away from the scientific name, which is consistent with those of related species. No such user (talk) 12:54, 2 August 2021 (UTC)

Agkistrodon piscivorus → Cottonmouth – WP:COMMONNAME (already redirects here). If not "Cottonmouth", then "" (which also redirects here). Both redirects have been stable for 5 years or longer. — BarrelProof (talk) 10:42, 8 July 2021 (UTC)

 * Move history note: As far as I can tell, the article was originally at "Cottonmouth" and was moved to the Latin binomial without formal discussion on 26 April 2006 by a user who said "Scientific names should be used for page names whenever possible to avoid confusion." Another user disagreed with that move and reverted it, saying "Use common names", but the mover insisted and moved it again on 29 April 2006, saying "Snake people use sci. names much more than common names." It has been at this title ever since, except for a self-reverted move to spelling variation of "Water moccasin" for 11 minutes in May 2021. — BarrelProof (talk) 18:21, 8 July 2021 (UTC)
 * See also the similar comment above by Quincy43425 on 28 February 2021, in the section entitled "Name change". — BarrelProof (talk) 01:24, 10 July 2021 (UTC)

There are two species of cottonmouths. Herpetologist (and ornithologist) and herpetological societies like the Society for the Study of Amphibians and Reptiles, and others, have been trying to establish standardized common names for reptile and amphibians for decades. The current and up to date list should be consulted before making changes.

Checklist of the Standard English Names of Amphibians & Reptiles Herpetologist and herpetological societies have discouraged the use of the name "water moccasin" since the 1960s. Common names for many North American and European species are probably ok if established standardized common names are followed, but for tropical species common names are not established or meaningful, and are often confusing with the same names often applied to many species. Keep in mind, with a shift in the last 20 to 30 years from morphologically based taxonomy to molecular (DNA) based taxonomy, and from traditional based  taxonomic theories to phylogenetic theories, many names that had been stable for decades and even centuries, are unstable, in a state of flux,  and change often.

— Preceding unsigned comment added by Wilafa (talk • contribs) 19:13, 9 July 2021 (UTC)

 * Wikipedia articles currently say there is only one cottonmouth species, with three subspecies and some intergradation. Even if somewhat rewritten in the future to reflect recent reclassification efforts, my understanding is that A. piscivorus remains the primary meaning of "cottonmouth" and "water moccasin", especially among nonspecialists. I think any ambiguity can be handled with a hatnote. (And SSAR appears to refer to the whole genus Agkistrodon as "American moccasins", so they don't seem to be trying very hard to discourage the use of "moccasin".) — BarrelProof (talk) 23:00, 9 July 2021 (UTC)

Wikipedia articles are currently out of date. The change was made in 2014.

Burbrink, Frank T. and Timothy J. Guiher. 2014. Considering gene flow when using coalescent methods to delimit lineages of North American pitvipers of the genus Agkistrodon. Zoological Journal of the Linnean Society, 173: 505–526. (http://cnah.org/pdf/88290.pdf)

the new and current arrangement is -
 * Agkistrodon piscivorus (Lacépéde, 1789), Northern Cottonmouth
 * Agkistrodon conanti (Gloyd, 1969), Florida Cottonmouth

Most of the scientific literature, as well as the new mainstream books and websites are using the new taxonomy, such as the most recent edition of the Peterson Field Guides and the Reptile Database

Powell, Conant & Collins. 2016. Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, 4th ed. Houghton Mifflin Harcourt Publishing Co. New York. 494 pp.

 * The Reptile Database: Agkistrodon piscivorus (Lacépéde, 1789)
 * The Reptile Database: Agkistrodon conanti (Gloyd, 1969)

As I stated, the name "water moccasin" has been discouraged. Water moccasin and American moccasins are not the same thing. WiLaFa (talk) 02:45, 10 July 2021 (UTC)

 * Even if somewhat rewritten in the future to reflect recent reclassification efforts, my understanding is that A. piscivorus remains the primary meaning of "cottonmouth", especially among nonspecialists. I think any ambiguity can be handled with a hatnote. — BarrelProof (talk) 03:24, 10 July 2021 (UTC)

In my opinion, the current Agkistrodon piscivorus article is out of date, and it could use some improvement in a few areas. If the name of the article is to be changed from the Latin name to the common name (which on this particular page I have no objections to), I would suggest the following -
 * Change the name of this article to Northern Cottonmouth (not Cottonmouth)
 * Create a new article for the Florida Cottonmouth
 * Then sort-out and edit what information in this article applies to which species and place it in the appropriate article. Some of it will apply to both.

While I certainly DO NOT think this work requires a PhD. herpetologist, I would hope anyone making these kinds of changes would have solid knowledge of the subject and an understanding of the impactions of the changes they make. The point is to improve Wikipedia and keep it up to date, not sidestep outdated information and compound problems in doing so.WiLaFa (talk) 04:56, 10 July 2021 (UTC)

 * Moving this article to (lowercase 'c' per WP:NCFAUNA) might be an improvement over the current name, but I don't really think that is a name in common use. The fact that the name is a red link is evidence of that. It's especially hard to think of this snake as a "Northern" animal, since it is only found in The South. There is already an article about the Florida cottonmouth, so there is no need to create one. — BarrelProof (talk) 07:15, 10 July 2021 (UTC)

You do have a couple of valid points, it is a snake with a distributional range in the south, and the name northern cottonmouth is not in common use either. However, the northern cottonmouth's distribution is "north" in relation to the other species of cottonmouth, the Florida cottonmouth. The name northern cottonmouth is not in common usage because it is new, as of 2014 when the taxonomy was changed.

Nevertheless, it is the new standardized common name, and it is being recommended and used by the scientist and specialist in the field, including all of the major herpetology societies: Society for the Study of Amphibians and Reptiles, the American Society of Ichthyologists and Herpetologists, and the Herpetologist's League. It is also slowly finding its way into popular usage and is being used by most of the new books, new editions of popular field guides, and websites. The Reptile Database is using it, iNaturalist is using it, and some pages on Wikipedia are using it, List of reptiles of North America. The IUCN Red List is not using it, but their Agkistrodon piscivorus page says it was last assessed on 1 March 2007 and needs updating.

I agree, "northern cottonmouth" was not a great choice for the standardized common name. But that is what has been proposed and generally accepted by the field of herpetology and it is slowly finding its way into popular science and mainstream publications on the subject. Wikipedia is not really the forum for challenging or arguing alternative views on taxonomy and nomenclature. A review, or some comments under the "Common names" heading of the article could certainly include some views or information on the subject, even about popular usage and perception. I wrote one for the Bothrops asper article a while back. But I think the name of this article should be Agkistrodon piscivorus or northern cottonmouth (either one).

If there are already articles for each of the old subspecies, I would suggest changing the name of the Agkistrodon piscivorus conanti, to Florida cottonmouth and updating the taxonomy to Agkistrodon conanti. Then merging the Agkistrodon piscivorus piscivorus and the Agkistrodon piscivorus leucostoma articles with the current article under the name northern cottonmouth.WiLaFa (talk) 20:31, 10 July 2021 (UTC)

Per: Naming conventions (fauna) Currency: "If the scientific name of animal has recently been changed (e.g. a species has been transferred into a different genus), and there is no reason to believe that the name change is contentious, use the new name regardless of usage in older reliable sources. It is not appropriate for us to retain archaic terminology while we wait for usage in older reliable sources to be swamped by usage in newer sources."WiLaFa (talk) 17:31, 11 July 2021 (UTC)
 * Support move to Cottonmouth; distinction from Florida cottonmouth can be accomplished with a slight addition to the existing hatnote. BD2412  T 18:08, 26 July 2021 (UTC)
 * Support per BarrelProof, history, and BD2412. Dicklyon (talk) 03:09, 29 July 2021 (UTC)

 * Oppose Article has been stable at this title since 26 April 2006. What is the harm in continuing to use the scientific name as the title? 17 articles link to [water moccasin]; 20 articles link to "cottonmouth"; 110+ articles link to "Agkistrodon piscivorus". That is WP:AT NATURALNESS on the part of editors. It simply is not possible to fulfill the WP:AT criteria of PRECISION and CONSISTENCY by using common/vernacular names as title for snakes (or most other organisms}. WP:COMMONNAME dates to an era when it wasn't certain that search engines would feature Wikipedia prominently, and it wasn't clear that Wikipedia would eventually grow to cover 350,000+ species of organisms (most of which are obscure, and only known by specialists). There are certainly cases where an organism is well known by a single vernacular name, which would be an appropriate title for Wikipedia. Venomous snakes native to English speaking countries are quite likely to be well known by a single vernacular name. However, Agkistrodon piscivorus is well known both as "water moccasin" and "cottonmouth" (with cottonmouth more popular recently). Talk:Crotalus concolor is another American venomous snake that ran into some complications with the vernacular name. And Talk:Killer whale has endless comments over which vernacular name is the best title. There haven't been any previous disputes about using the scientific name as the title of this article. Plantdrew (talk) 03:49, 31 July 2021 (UTC)

 * Opposed I think Wikipedia should follow science on the name of a species. It should not be a "vote for your favorite popular name contest". Otherwise what is Wikipedia really doing? This is one of two species of cottonmouths, and it has a Latin name Agkistrodon piscivorus, and a standardized English common name northern cottonmouth. I am in favor of using the Latin name first, the English name second, and opposed to any other names.WiLaFa (talk) 20:17, 31 July 2021 (UTC)
 * The answer to your question of "what is Wikipedia really doing?" is that Wikipedia is choosing the WP:COMMONNAME. That is the Wikipedia policy. — BarrelProof (talk) 15:31, 1 August 2021 (UTC)

What I mean by that is, Wikipedia should be educating people, not reinforcing outdated and obsolete information because it is familiar, and ignoring new information because it is not familiar to people. There used to one species of cottonmouth, now there are two.

Also, see heading Currency under Naming conventions (fauna)

Cottonmouth does not meet "the five criteria" listed in your link.

"Precision – The title unambiguously identifies the article's subject and distinguishes it from other subjects. "

cottonmouth is ambiguous, there are two different species. "Conciseness – The title is no longer than necessary to identify the article's subject and distinguish it from other subjects. "

cottonmouth is not concise for the same reason above.

"Consistency – The title is consistent with the pattern of similar articles' titles. "

Of the 16 pages in the Category: Agkistrodon, 14 use are using the Latin names and have been for years, and the two that are not where just changed in the last 20 days (one at your request). WiLaFa (talk) 17:52, 1 August 2021 (UTC) The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

Move to cottonmouth
Common name pretty clearly the standard for animal names. the last move attempt seemed 50/50. The opposed votes seem to be opposed because they feel Wikipedia as a whole should use scientific names instead. but the fact is that Wikipedia prefers common names and the fact that this article isn’t at the common name makes the website more inconsistent and makes this article look like it’s a stub. 97.126.89.248 (talk) 00:32, 18 August 2023 (UTC)

 * Opposed WiLaFa (talk) 03:28, 19 August 2023 (UTC)
 * Why? 97.126.89.248 (talk) 07:37, 21 August 2023 (UTC)
 * See discussion above. WiLaFa (talk) 04:06, 22 August 2023 (UTC)
 * Then why bother commenting opposed here? I saw you were opposed 97.126.89.248 (talk) 18:24, 23 August 2023 (UTC)

Scientific or common name?

 * For possible future discussions.
 * First, this article really needs updating. Agkistrodon piscivorus piscivorus and the Western cottonmouth (Agkistrodon piscivorus leucostoma) should be discussed for merging.
 * I can't imagine any benefit of keeping the above articles. For a long time they have been wrongly classified as subspecies. However, indepth research articles have been written on supposed subspecies like: "testis of the male Western Cottonmouth Snake, Agkistrodon piscivorus leucostoma".

Northern cottonmouth

 * user:Wilafa's suggestions of "Northern Cottonmouth" has merit as there are a multitude of states, universities, organizations, and media, that use the common name "Northern Cottonmouth". In the US, especially in areas where there are no possible hybrids (hybrid zones), it is common to find the nomenclature of just cottonmouth or water moccasin as there is no confusion with other snakes in these areas.
 * Scientific nomenclature on articles are expected when there is not a clear unambiguous more common name. The suggested names "Cottonmouth" and "Water moccasin" (or combination "Cottonmouth water moccasin") seem too vague for a world-wide encyclopedia. The Mexican moccasin (Agkistrodon bilineatus), commonly called the "Black moccasin", Mexican moccasin, cantil, or Mexican cantil, should be considered even though these alternate names still only refer to the same Agkistrodon bilineatus.

Resources

 * States that use "Northern Cottonmouth":

 * Oklahoma,
 * Missouri,
 * Washington University in St. Louis lists the Northern Cottonmouth (Agkistrodon piscivorus) but also still lists the Western Cottonmouth (Agkistrodon piscivorus leucostoma).
 * Illinois,
 * Louisiana,
 * Virginia is titled "Snakes on the Water: Cottonmouth or Watersnake?] and the image has the caption "Northern cottonmouth (venomous)"

Organizations

 * South Carolina Partners in Amphibian and Reptile Conservation (SCPARC), formally the South Carolina Herpetological Society
 * The Virginia Herpetological Society
 * Note: herpsofarkansas uses Agkistrodon piscivorus subtitled Northern Cottonmouth
 * Texas A&M University title: "Detectability of Northern Cottonmouth Snakes (agkistrodon Piscivorus) Within Constructed Wetland Complex"
 * Sam Houston State University title: Foraging Activity Time and Refuge Site Selection in the Northern Cottonmouth, Agkistrodon Piscivorus"
 * The Kansas Herpetofaunal Atlas: Titled: Northern cottonmouth Agkistrodon piscivorus (Lacepede 1789)

Media

 * Shreveport Times: Northern cottonmouth
 * Newsweek lists; Northern cottonmouth water moccasin.
 * Springfield News-Leader: "The northern cottonmouth — the type of cottonmouth found in Missouri..."
 * The Advocate covers a story of 6,000 posters being distributed to Louisiana schools identifying eight venomous snakes in the state. The first snake on the poster is listed as the Northern cottonmouth.

General websites

 * expert website
 * "The Maligned Cottonmouth" Image of snake with the caption "Agkistrodon piscivorus (Northern Cottonmouth)"

Out of date information
Otr500 (talk) 09:03, 19 September 2023 (UTC)
 * Alabama still recognizes three subspecies, with the "Eastern cottonmouth (Agkistrodon piscivorus)".
 * Tennessee uses Agkistrodon piscivorus but also still recognizes Western Cottonmouths.
 * North Carolina still uses "Eastern cottonmouth".
 * JSTOR uses the Eastern Cottonmouth (Agkistrodon piscivorus).
 * The above information was found on a fast search meaning there are likely more examples. --  Otr500 (talk) 09:03, 19 September 2023 (UTC)

 * I think northern cottonmouth is fine. I don't think it's a real common name, more of a technical name. That articles titled Cottonmouth and Florida cottonmouth would be fine but clearly others don't. I would support a move to northern cottonmouth.
 * As off topic rant, I don't like that the bar for species has moved from produces viable offspring to something more vague. Agkistrodon piscivorus and conanti have overlapping ranges and commonly hybridize in the wild, so it's unclear to me how they are different species. But sources are sources. Always beleive in hope (talk) 21:19, 20 September 2023 (UTC)

Areas needing work

 * Aside from the title naming issue the "Description" section (second and fourth paragraphs) has content concerning the A. p. piscivorus. that needs removing or rewording.
 * The list in the "Common names" section (58 of them) are sourced from the single source "Handbook of Snakes of the United States and Canada". The understood meaning of WP:COMMONNAMES on Wikipedia would be a name "that is most commonly used (as determined by its prevalence in a significant majority of independent, reliable English-language sources). There should be at least some sources and not one single source. Listing 58 names found in one source is overboard. Names that could be considered common, meaning someone might look for the subject by that name, should have a redirect to avoid confusion. This would include "cottonmouth", "northern cottonmouth", and "water moccasin". I may have missed it but I could not find anything under "swamp moccasin" for this snake. Loyola University New Orleans referred to the subject as Omnivore of the Wetlands but that does not make it a common name. I could find no sources to indicate this snake is considered the "black moccasin". It is a common name of the Agkistrodon bilineatus (Mexican cantil) and not the Lampropeltis getula as the set index article shows.
 * The last sentence of the last paragraph of the "Feeding" section, Burmese pythons are an invasive species in Florida with the capacity to inflict great damage to the local ecosystem, so it is hoped that A. piscivorus may be in the process of modifying its diet to enable it to hunt the pythons, is unsourced begging a maintenance tag.
 * The subject snake is considered an opportunistic feeder and will eat smaller pythons, including tracking transmitters. As an opportunistic feeder pretty much anything in it's area may become prey.

Appendices

 * The explanatory essay Further reading states The Further reading section of an article contains a bulleted list of a reasonable number of works that a reader may consult for additional and more detailed coverage of the subject. Somehow I do not consider 48 entries to be "a reasonable number of works". The "Limited" section has more on that. For any that might cry "it is only an essay", I would submit that some essays are used by a broad majority so are more relevant than others. Here to build an encyclopedia (WP:NOTHERE) is an "explanatory essay" but if someone runs afoul of this they can be banned or blocked. Maybe a reason to wonder why it hasn't been promoted. Also, MOS:FURTHER, refers to this essay and states "An optional bulleted list, usually alphabetized, of a reasonable number of publications".
 * The External links section has six links. Some things just grow overtime. This is one of the optional appendices. Three seems to be an acceptable number and of course, everyone has their favorite to add for four links.
 * The problem is that none is needed for article promotion.

 * ELpoints #3) states: Links in the "External links" section should be kept to a minimum. A lack of external links or a small number of external links is not a reason to add external links.
 * LINKFARM states: There is nothing wrong with adding one or more useful content-relevant links to the external links section of an article; however, excessive lists can dwarf articles and detract from the purpose of Wikipedia. On articles about topics with many fansites, for example, including a link to one major fansite may be appropriate.
 * ELMIN: Minimize the number of links. --
 * ELCITE: (Not relevant here) Do not use cite web or other citation templates in the External links section. Citation templates are permitted in the Further reading section.
 * WP:ELBURDEN: Disputed links should be excluded by default unless and until there is a consensus to include them.

Possible B-class

 * There is credible evidence that the article should be reclassified. The B-class criteria #2 states: The article reasonably covers the topic, and does not contain obvious omissions or inaccuracies. It contains a large proportion of the material necessary for an A-Class article, although some sections may need expansion, and some less important topics may be missing.
 * Considering taxonomic changes do not recognize any subspecies, yet there are more than a few articles on these "subspecies" and visual differences. The hybrid zone might be responsible for introgressive hybridization (hybridization and backcrossing) might explain different populations of a single species, or possibly species divergence. There may be too much for a single article. Certainly, now, there is a lot of missing material that questions that the article now "reasonably covers the topic". The other articles on non-recognized subspecies will need to be dealt with. The entire subject may require a specialist. -- Otr500 (talk) 01:44, 24 October 2023 (UTC)

title: Talk:Agkistrodon piscivorus


text:
SS Chelyuskin

SS Chelyuskin («Челю́скин») was a Soviet steamship, reinforced to navigate through polar ice, that in 1934 became ice-bound in Arctic waters during a navigation along the Northern Maritime Route from Murmansk to Vladivostok and sank. 111 people were on board the Chelyuskin, and all but one were rescued by air. The expedition's task was to determine the possibility to travel by non-icebreaker through the Northern Maritime Route in a single navigation season.

It was built in Denmark in 1933 by Burmeister and Wain (B&W, Copenhagen) and named after the 18th century Russian polar explorer Semion Ivanovich Chelyuskin. The head of the expedition was Otto Yuliyevich Shmidt and the ship's captain was V. I. Voronin. There were 111 people on board the steamship, including Soviet cinematographers Mark Troyanovsky and Arkadii Shafran who documented on film the entire voyage, including the rescue. The crew members were known as Chelyuskintsy, with the singular form "Chelyuskinets".

Mission
After leaving Murmansk on 2 August 1933, the steamship managed to get through most of the Northern Route before it was caught in the ice fields in September. Eight members of the crew had been dropped off at Kolyuchin Island, so there were 104 people on board including 10 women and two small children. One of the children was only 6 months old: geodesicist Vasily Vasiliev's daughter Karina, born on August 31, 1933, during the voyage in the Kara Sea. After becoming icebound, the ship drifted in the ice pack before sinking on 13 February 1934, crushed by the icepacks near Kolyuchin Island in the Chukchi Sea. During the wreck one crew member, B. G. Mogilevich, was killed by deck cargo. The survivors made a camp on the ice floe. The women and children were airlifted out by Anatoly Liapidevsky on March 5 after 29 rescue flight attempts, but the men in the crew were not rescued until April after over two months on the ice. The crew managed to escape onto the ice and built a makeshift airstrip using only a few spades, ice shovels and two crowbars. They had to rebuild the airstrip thirteen times, until they were rescued in April of the same year and flown to the village of Vankarem on the coast of the sea. From there, some of the Chelyuskinites were flown further to the village of Uelen, while fifty-three men walked over 300 miles to get there.

The aircraft pilots who took part in search and rescue operations were the first people to receive the newly established highest title of Hero of the Soviet Union. Those pilots were Anatoly Liapidevsky, Sigizmund Levanevsky (who crashed en route to the camp, but survived), Vasily Molokov, Mavriky Slepnyov, Mikhail Vodopianov, Nikolai Kamanin and Ivan Doronin. Liapidevsky flew an ANT-4, the civilian version of the TB-1 heavy bomber, while Slepnev and Levanevsky flew a Consolidated Fleetster specially brought in from the US for the mission, and the other pilots flew the Polikarpov R-5. Two American air mechanics, Clyde Goodwin Armitstead, and William Latimer Lavery, also helped in the search and rescue of the Chelyuskintsy, on 10 September 1934, and were awarded the Order of Lenin.

As the steamship became trapped at the entrance to the Bering Strait, the USSR considered the expedition mainly successful, as it had proven that a regular steamship had a chance to navigate the whole Northern Maritime Route in a single season. After a few additional trial runs in 1933 and 1934, the Northern Sea Route was officially opened and commercial exploitation began in 1935. The following year part of the Soviet Baltic Fleet made the passage to the Pacific where an armed conflict with Japan was looming.

Legacy
In the wake of the catastrophe, a central square in Yaroslavl was renamed after the Chelyuskintsy, as was Chelyuskinites Park in Minsk. Marina Tsvetayeva wrote a poem applauding the rescue team. Nine days after the two Soviet cameramen aboard reached Moscow, their footage was developed, edited and released as a feature documentary motion picture. In 1970, East German television produced Tscheljuskin, a film about the ship's voyage, directed by Rainer Hausdorf and featuring Eberhard Mellies as Prof. Schmidt, Dieter Mann as the surveyor Vasiliev and Fritz Diez as Valerian Kuybyshev.

Efforts to find the wreck of the ship were made by at least four different expeditions, and it was finally discovered in September 2006, at a depth of about 50 metres in the Chukchi Sea. The polar explorer Artur Chilingarov argued that the ship should be raised and converted into a museum.

Michael Roberts, an English poet, wrote a poem "Chelyuskin", which was included in his collection Poems, published by Jonathan Cape in 1936.

The story was dramatised in the radio drama The Cruise of the Chelyuskin.

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: SS Chelyuskin


text:
Cornerback

A cornerback (CB) is a member of the defensive backfield or secondary in gridiron football. Cornerbacks cover receivers most of the time, but also blitz and defend against such offensive running plays as sweeps and reverses. They create turnovers through hard tackles, interceptions, and deflecting forward passes.

Other members of the defensive backfield include strong and free safeties.

The cornerback position requires speed, agility, strength, and the ability to make rapid sharp turns. A cornerback's skill set typically requires proficiency in anticipating the quarterback, backpedaling, executing single and zone coverage, disrupting pass routes, block shedding, and tackling. Cornerbacks are among the fastest players on the field. Because of this, they are frequently used as return specialists on punts or kickoffs.

Overview
The cornerback's chief responsibility is to defend against the offense's pass. The rules of American professional football and American college football do not mandate starting position, movement, or coverage zones for any member of the defense. There are no "illegal defense" formations. Cornerbacks can be anywhere on the defensive side of the line of scrimmage at the start of play, although their proximity, formations, and strategies are outlined by the coaching staff or captain. Examples of cornerbacks in the NFL are Jalen Ramsey, Patrick Surtain II, Marlon Humphrey, Jaire Alexander, Sauce Gardner, L'Jarius Sneed, and Charvarius Ward.

Most modern National Football League defensive formations use four defensive backs (two safeties and two corners); Canadian Football League defenses generally use five defensive backs (one safety, two defensive halfbacks, and two corners). A cornerback's responsibilities vary depending on how the defense assigns protection to its defensive secondary. In terms of defending the run, often corners may be assigned to blitz depending on the coaching decisions in a game. In terms of defending passing plays, a corner will be typically assigned to either zone or man-to-man coverage.

The most effective cornerbacks are typically called "lockdown corners". These elite defenders cover an offensive receiver so effectively on either side of the field that the quarterback does not target the receiver being covered.

Zone
In zone coverage, the cornerback defends an assigned area of the field. Many schemes and variations were created to provide defensive coordinators great latitude and flexibility which aim to thwart offensive schemes.

When a team is using zone coverage, some areas of the field require special attention when defending against specific pass plays. They include the flats (to defend the screen pass and hitch routes), mid range zones including the void (to defend the "stop n go", quick post, fade, hook, curl, and "sideline" or "out" routes), and finally the deep zones (to defend the post/deep post, chair, streak, "fly", "go", bomb, or Hail Mary routes). These are basic terms (perhaps the most generic) for the basic zones and routes which vary system to system, league to league, and team to team.

Advanced forms of coverage may involve "quarterback spies" and "containment" coverages, as well as various "on field adjustments" that require shifts and rotations; the latter usually initiated by the captain of the secondary (typically the free safety) during the quarterback's cadence. At this time the captain attempts to "read" the alignment (pro set, split set, trips, etc.) of the offensive "skill players" (backs and receivers) in order to best predict and counter the play the offense will run. He will base his decision on past experience, game preparation, and a sound comprehension of his teammates strengths, abilities, and tendencies. These adjustments may change on a play by play basis, due to substitutions or even evolving weather or field conditions. For example, defensive coordinators may favor a tendency to play a less aggressive containment style zone coverage during wet or slippery field conditions to avoid problems associated with over-pursuit (when a defender takes a poor angle on a ball carrier and cannot redirect in time due to poor footing).

Cover 1
The Cover 1 defense is an aggressive formation employed against offenses trying to gain short yardage. In the Cover 1 defense, one defender—normally a safety—plays deep zone downfield, providing security over the top and freeing the other safety to rush the line of scrimmage or drop back into coverage. Meanwhile, the corner's primary responsibility is to play on or off the receiver and not release him vertically. Defensive coordinators typically call for Cover 1 formations only when their cornerbacks are skilled at playing man-to-man coverage.

Cover 2
The Cover 2 formation, which deploys four defensive backs in a "two-deep zone", is popular among NFL defensive coordinators because it uses two safeties to defend the deep routes instead of one. The safeties line up on or near their respective hashmarks between 11 and 15 yards off the line of scrimmage, while the cornerbacks line up around five yards from the wide receivers nearest to each sideline. With the safeties able to watch the play develop in front of them, the corners are free to pursue a more aggressive style of play.

In Cover 2, the cornerback is usually responsible for "containment", meaning that he is tasked with preventing any eligible receiver or ball carrier from running between him and the sideline. He funnels receivers toward the middle of the field and may physically "jam" them within five yards of the line of scrimmage in order to disrupt their assigned routes. If he determines that the offense is not attempting a running play or a pass into the flat, he then drops back to defend the secondary. This is often referred to as the "catch-and-run" technique. Typically, cornerbacks mirror each other's zone responsibilities. However, sometimes they play a "man-up" style of bump-and-run coverage designed to eliminate the short pass, where the receiver is forced to the near sideline, which is the opposite of the run-oriented "containment" style of Cover 2.

Cover 3
In a "Cover 3", the two corners and free safety defend their assigned deep thirds of the field, where the corners defend the outside thirds, (hence the term corner) while the safety defends the middle third. This allows the strong safety to address a full range of duties depending on what reads he makes coupled with the coverage called. These duties may simply include single or zone coverage, being a quarterback spy, providing extra run support in short yardage situations, or to stunt or blitz through a gap or from the end.

Cover 4
In a "Cover 4" each defensive back is responsible for covering his designated "deep fourth" of the field, while other defensive players are responsible for covering the underneath areas. Sometimes Cover 4 is used as a "prevent defense".

Variations of these coverages exist to counter the many styles of offenses a defense may face on any given week. For example, one variation of the Cover 2 allocates the weak-side corner (e.g.: typically the "right cornerback" when playing against right-handed quarterbacks) to cover half the field in order to free up a safety; the idea being to allow the safety to engage a different part of the field, blitz, contain, or spy. The strong side cornerback (the "left cornerback") may be in a variety of different alignments which may include "loose man", "man-under", or "man-up". Although these are forms of single coverage, more often than not his responsibility is usually limited to an initial jam and funnel with a subsequent drop back into the "void". This pie-shaped slice of field is included with your most basic 2 Deep Zone coverage. One interesting aspect sometimes encountered with Cover 2 is that it is possible for one corner to be in a zone coverage, where he funnels and drops into the void, while another may be in man coverage. However, your basic garden variety 2 Deep Zone usually employs the two safeties to share half the field responsibilities, with the two corners funneling.

Jamming the receiver

When a cornerback is attempting to jam a receiver, he is trying to disrupt the receiver's route at the line of scrimmage. Many routes are precisely coordinated between the quarterback and the receiver, to the point that a quarterback may throw the ball without looking, knowing his receiver will be in an exact spot after a certain time. Jamming will disrupt the timing between the two, which provides the defense with extra time to sack the quarterback (sometimes called a "coverage sack"), or force an ill-timed throw that misses the target. In addition, a proper jam allows the safety or linebacker to provide stronger run support because he then has more time to drop back into zone coverage in the event of a pass. In other words, he has been granted more time by the corner to recover from his mistakes if he anticipates a run when in fact the play is a pass.

Proper jamming technique requires the cornerback to use their legs, shoulder width apart. At the same time, the cornerback thrusts their arms forward into the receiver's chest to maximize power. When properly executed, a jam can knock a receiver off his feet. Jamming is only legal within five yards from the line of scrimmage.

If the jam fails, the cornerback is usually flat footed and not in a suitable position to defend the mid to long-range passes. When this occurs, the safeties and linebackers usually cannot return to their zone obligations in time, especially if they were anticipating a run as the play began. In essence, the defense is unnecessarily "stretched" to its breaking point. Receivers who can effectively avoid the jam and stretch defenses are far more likely to create big play opportunities for the offense. Therefore, it is vital that a cornerback execute a proper funnel or jam to allow safeties and linebackers enough time to return to their zone responsibilities in the event of an unforeseen pass play. By working together and familiarizing where one's help may come from, a higher degree of confidence is established among the defensive secondary as a unit, with the end result translating into a much more formidable defense against both the run and pass.

Single/man-to-man coverage
In single or man to man coverage, the cornerback is responsible for a particular receiver assigned to him. As the play begins, the corner may either attempt to "jam" the receiver at the line, play a step or two off of him, or concede a few yards and play with a "cushion". Cushions can range from a yard or two, to forty yards in a "prevent defense" situation. Cushion is just how far off the defender plays away from the offensive player he is assigned to defend. When lining up in front of the receiver to "jam" him or playing just a few steps off, it is important that the corner keeps his body in front of the receiver's body. The easiest way for a corner to be in position is to line up slightly inside of the receiver and the ball, and keep his eyes looking between the receiver's hip and his knees. If a cornerback loses focus on his receiver, the receiver will run straight past him, and then it leads to corners having to use the cushion technique. Generally, cushions are smaller in single coverage and larger in zone coverage.

Single coverage in the "red zone" – the area between the twenty-yard line and the goal line – is usually designed to prevent receivers from slanting towards the middle of the field. These types of routes are difficult to stop in the red zone because this area is usually congested with bodies colliding, crossing, and weaving in different directions. Although illegal, defenders are easily picked or screened by opposing receivers and sometimes by their own teammates; this is illegal yet difficult to enforce in short field, congested situations. To avoid this, it is often favorable for cornerbacks to either: "switch" assignments, where he will agree beforehand to trade assignments with one of his fellow defenders if the receivers criss-cross as the play begins, or alternatively, if a corner may instead line up very close to the receiver at the line of scrimmage to force or "jam" him toward the sideline (outside) without violating the 5-yard no-touch rule. Corners often refer to this second style of coverage as the "man under" technique.

Single coverage, or man to man coverage usually employs relatively few techniques. However, they are often initially displayed to resemble one another as much as possible to disguise the true motives of the defense, and be interchangeable as well. Although terminology for single coverage can vary, a few generic terms have been included to establish a general understanding of cornerback philosophy and how his function relates to the rest of the defense.

Loose man
Loose man requires cornerbacks to play off the receiver with a five to ten yard cushion. He usually does not touch the receiver and tries to keep his head on a swivel in order to move in whatever direction the receiver decides to shape his route. Typically with loose man coverage, the cornerback has little or no help from the safety in defending against the receiver.

This defense is used to discourage deeper passes, but often allows short yardage passes. A loose-man defense looks to create confusion for the quarterback by using blitzes. The idea is to disrupt the coordination necessary for short routes, which leads to drops or poorly thrown passes stalling the drive. However, accurate quarterbacks with a quick release of the football can exploit this and routinely make 3 to 5 yard completions to receivers.

Man up
By far the most challenging, the man up technique grants the wide receiver a relatively free release as the corner shadows him stride for stride everywhere he goes. The cornerback's objective here is to position himself between the quarterback and the receiver, without knowing where the receiver is going. As the ball is snapped the corner will initially ignore the quarterback, turn and run with the receiver and hope the ball does not drop out of the sky before he can react to it. Corners must also hope the receiver does not change directions when it is time to sneak a peek at the quarterback in effort to discover where the ball is. A wet field makes this coverage extremely difficult. In addition, a perfect throw is hard, if not impossible, to stop. This coverage is usually reserved for the elite cornerback with superb coverage skills.

title: Cornerback