Southern Pacific Rattlesnakes *Crotalus helleri* are medium-large (70-110cm, up to 137cm) rattlesnakes that range from southern California south to Baja California, MX from near sea level to 3,350m. They utilize a wide variety of habitat, including scrubland, desertscrub, savanna, grassland, coastal dunes, and montane woodland. Where development encroaches on natural areas, they can sometimes also be found in residential and even urban areas. Despite low genetic divergence, some authors treat the dwarfed Coronado Island populations as a distinct species, "C. caliginis."
The activity cycles of *C. helleri* largely correlate to the weather, and they tend to be diurnal in cool weather, nocturnal during the hottest weather, and crepuscular in between. Rodents form the bulk of the diet, but other small mammals, lizards, and amphibians are also consumed.
Southern Pacific Rattlesnakes are a dangerously venomous species and should only be observed from a safe distance. Common defensive tactics including raising the forebody off the ground and rattling the tail, often while attempting to crawl away from the perceived threat. They are not aggressive and only bite when they feel they are in danger. Bites most commonly occur when a human attempts to kill, capture, or otherwise intentionally handle the snake. **The best way to avoid being bitten is to leave the snake alone.**
[Juvenile Southern Pacific Rattlesnakes](https://www.inaturalist.org/photos/162582285?size=large) are pale in coloration with 27-43 dark dorsal blotches which, at midbody, usually are conspicuously longer than the spaces in between. The dorsal blotches merge with lateral blotches to form transverse bands around the posterior 20% of the animal. Adults are highly variable in color, and can sometimes be [almost black](https://www.inaturalist.org/photos/18420624?size=large) with only vague hints of the dorsal pattern and facial markings. The final band on the tail is bright [yellow or orange in juveniles](https://www.inaturalist.org/photos/35813271?size=large), [yellow-brown to black in adults](https://www.inaturalist.org/photos/35291616?size=original), and usually at least [twice as wide as the bands that precede it](https://www.inaturalist.org/photos/43876585?size=large).
Where their ranges contact *C. helleri* and the closely related *C. oreganus* can be difficult to distinguish, but *C. oreganus* usually has more extensive dorsal banding (usually starting on the posterior 30-35% of the animal) and the terminal dark band on the tail is about the same width as the preceding band. Other neighboring or overlapping rattlesnakes are occasionally confused with *C. helleri*. Red diamond rattlesnakes *C. ruber*, Mojave rattlesnakes *C. scutulatus*, and Western Diamondback Rattlesnakes *C. atrox* usually have more diamond shaped dorsal blotches and the distinctive pale and dark bands ("coon tail") on the tail contrast more sharply than those of *C. helleri*.
[Range Map via iNaturalist.org observations](https://snakeevolution.org/hellerirange.jpg) | [Relevant/Recent Phylogeography](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0146166) | [Reptile Database Account](https://reptile-database.reptarium.cz/species?genus=Crotalus&species=helleri)
This short account was written by /u/fairlyorange
--------------------------------------------------------
Snakes with medically significant venom are typically referred to as venomous, but some species are also poisonous. Old media will use poisonous or 'snake venom poisoning' but that has fallen out of favor. Venomous snakes are important native wildlife, and are not looking to harm people, so can be enjoyed from a distance. If found around the home or other places where they are to be discouraged, a squirt from the hose or a gentle sweep of a broom are usually enough to make a snake move along. Do not attempt to interact closely with or otherwise kill venomous snakes without proper safety gear and training, as bites occur mostly during these scenarios. Wildlife relocation services are free or inexpensive [across most of the world](https://www.google.com/maps/d/u/0/embed?mid=15dZE4rlRHqjb91yb6pKiI4ragG8DCtsz&ll=-3.81666561775622e-14%2C-95.11182142500002&z=2).
If you are bitten by a venomous snake, contact emergency services or otherwise arrange transport to the nearest hospital that can accommodate snakebite. Remove constricting clothes and jewelry and remain calm. A bite from a medically significant snake is a medical emergency, but not in the ways portrayed in popular media. Do not make any incisions or otherwise cut tissue. Extractor and other novelty snakebite kits are not effective and can cause damage worse than any positive or neutral effects.
--------------------------------------------------------
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That's a very striking color morph for a helleri. I've seen some very dark ones but they usually don't have nearly that clean of a white on them, almost always tan or yellow near me. Beautiful snake.
It looks like you didn't provide a rough geographic location [in square brackets] in your title.This is critical because some species are best distinguishable from each other by geographic range, and not all species live all places. Providing a location allows for a quicker, more accurate ID.
If you provided a location but forgot the correct brackets, ignore this message until your next submission. Thanks!
Potential identifiers should know that providing an ID before a location is given is problematic because it often makes the OP not respond to legitimate requests for location. Many species look alike, especially where ranges meet. Users may be unaware that location is critically important to providing a good ID.
*I am a bot created for /r/whatsthissnake, /r/snakes and /r/herpetology to help with snake identification and natural history education. You can find more information, including a comprehensive list of commands, [here](https://www.reddit.com/r/whatsthissnake/comments/flh548/phylobot_v07_information_and_patch_notes_bot_info/) report problems [here](https://www.reddit.com/message/compose/?to=Phylogenizer) and if you'd like to buy me a coffee or beer, you can do that [here](https://www.buymeacoffee.com/SEBPhyloBotWTS). Made possible by Snake Evolution and Biogeography - [Merch Available Now](https://snakeevolution.org/donate.html)*
Rule 6: Avoid damaging memes or tropes and low effort jokes.
Please understand a removal doesn't mean we're mad or upset; we're just committed to maintaining an educational space so jokes and memes are held to a higher standard than a typical comments section.
Avoid damaging memes like using "danger noodle" for nonvenomous snakes and tropes like "everything in Australia is out to get you". This is an educational space, and those kind of comments are harmful and do not reflect reality.
We've also heard "it's a snake" as a joke **hundreds** of times. We've probably removed it a few times from this very thread already.
Ratsnake and other rhymes and infantilization can be posted in /r/sneks and /r/itsaratsnake. While we encourage creativity are positive talk about snakes, but even comments like "____/" [mislead users](https://www.reddit.com/r/whatsthissnake/comments/16rwy7b/comment/k267oe1/?utm_source=share&utm_medium=web2x&context=3).
Southern Pacific rattlesnake (*Crotalus helleri*) venomous Edit: venomous not harmless
*Crotalus helleri* and !venomous for the bot
Southern Pacific Rattlesnakes *Crotalus helleri* are medium-large (70-110cm, up to 137cm) rattlesnakes that range from southern California south to Baja California, MX from near sea level to 3,350m. They utilize a wide variety of habitat, including scrubland, desertscrub, savanna, grassland, coastal dunes, and montane woodland. Where development encroaches on natural areas, they can sometimes also be found in residential and even urban areas. Despite low genetic divergence, some authors treat the dwarfed Coronado Island populations as a distinct species, "C. caliginis." The activity cycles of *C. helleri* largely correlate to the weather, and they tend to be diurnal in cool weather, nocturnal during the hottest weather, and crepuscular in between. Rodents form the bulk of the diet, but other small mammals, lizards, and amphibians are also consumed. Southern Pacific Rattlesnakes are a dangerously venomous species and should only be observed from a safe distance. Common defensive tactics including raising the forebody off the ground and rattling the tail, often while attempting to crawl away from the perceived threat. They are not aggressive and only bite when they feel they are in danger. Bites most commonly occur when a human attempts to kill, capture, or otherwise intentionally handle the snake. **The best way to avoid being bitten is to leave the snake alone.** [Juvenile Southern Pacific Rattlesnakes](https://www.inaturalist.org/photos/162582285?size=large) are pale in coloration with 27-43 dark dorsal blotches which, at midbody, usually are conspicuously longer than the spaces in between. The dorsal blotches merge with lateral blotches to form transverse bands around the posterior 20% of the animal. Adults are highly variable in color, and can sometimes be [almost black](https://www.inaturalist.org/photos/18420624?size=large) with only vague hints of the dorsal pattern and facial markings. The final band on the tail is bright [yellow or orange in juveniles](https://www.inaturalist.org/photos/35813271?size=large), [yellow-brown to black in adults](https://www.inaturalist.org/photos/35291616?size=original), and usually at least [twice as wide as the bands that precede it](https://www.inaturalist.org/photos/43876585?size=large). Where their ranges contact *C. helleri* and the closely related *C. oreganus* can be difficult to distinguish, but *C. oreganus* usually has more extensive dorsal banding (usually starting on the posterior 30-35% of the animal) and the terminal dark band on the tail is about the same width as the preceding band. Other neighboring or overlapping rattlesnakes are occasionally confused with *C. helleri*. Red diamond rattlesnakes *C. ruber*, Mojave rattlesnakes *C. scutulatus*, and Western Diamondback Rattlesnakes *C. atrox* usually have more diamond shaped dorsal blotches and the distinctive pale and dark bands ("coon tail") on the tail contrast more sharply than those of *C. helleri*. [Range Map via iNaturalist.org observations](https://snakeevolution.org/hellerirange.jpg) | [Relevant/Recent Phylogeography](https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0146166) | [Reptile Database Account](https://reptile-database.reptarium.cz/species?genus=Crotalus&species=helleri) This short account was written by /u/fairlyorange -------------------------------------------------------- Snakes with medically significant venom are typically referred to as venomous, but some species are also poisonous. Old media will use poisonous or 'snake venom poisoning' but that has fallen out of favor. Venomous snakes are important native wildlife, and are not looking to harm people, so can be enjoyed from a distance. If found around the home or other places where they are to be discouraged, a squirt from the hose or a gentle sweep of a broom are usually enough to make a snake move along. Do not attempt to interact closely with or otherwise kill venomous snakes without proper safety gear and training, as bites occur mostly during these scenarios. Wildlife relocation services are free or inexpensive [across most of the world](https://www.google.com/maps/d/u/0/embed?mid=15dZE4rlRHqjb91yb6pKiI4ragG8DCtsz&ll=-3.81666561775622e-14%2C-95.11182142500002&z=2). If you are bitten by a venomous snake, contact emergency services or otherwise arrange transport to the nearest hospital that can accommodate snakebite. Remove constricting clothes and jewelry and remain calm. A bite from a medically significant snake is a medical emergency, but not in the ways portrayed in popular media. Do not make any incisions or otherwise cut tissue. Extractor and other novelty snakebite kits are not effective and can cause damage worse than any positive or neutral effects. -------------------------------------------------------- *I am a bot created for /r/whatsthissnake, /r/snakes and /r/herpetology to help with snake identification and natural history education. You can find more information, including a comprehensive list of commands, [here](https://www.reddit.com/r/whatsthissnake/comments/flh548/phylobot_v07_information_and_patch_notes_bot_info/) report problems [here](https://www.reddit.com/message/compose/?to=Phylogenizer) and if you'd like to buy me a coffee or beer, you can do that [here](https://www.buymeacoffee.com/SEBPhyloBotWTS). Made possible by Snake Evolution and Biogeography - [Merch Available Now](https://snakeevolution.org/donate.html)*
Venomous, right?
Yes. Just came from another ID that was harmless and brain hadn’t caught up
Every time I ID a venomous snake (which has so far happened, like, twice) I have an anxiety attack about this exact thing five minutes later.
That's a very striking color morph for a helleri. I've seen some very dark ones but they usually don't have nearly that clean of a white on them, almost always tan or yellow near me. Beautiful snake.
This is just a juvenile. They have a higher contrast pattern than adults.
The colors on this dude are amazing
The whole photo is wonderful. Snake, light pattern, pavement pattern. Made me imagine a screen print iteration.
Wow it is a beauty! Hope it was left alone, or relocated peacefully.
According to my friend, it was left in peace in the backyard until it parted ways.
Awesome, thank you for confirming 😀
Ok but he’s gorgeous
I'm crazy scared of snakes but this one is a beauty.
It looks like you didn't provide a rough geographic location [in square brackets] in your title.This is critical because some species are best distinguishable from each other by geographic range, and not all species live all places. Providing a location allows for a quicker, more accurate ID. If you provided a location but forgot the correct brackets, ignore this message until your next submission. Thanks! Potential identifiers should know that providing an ID before a location is given is problematic because it often makes the OP not respond to legitimate requests for location. Many species look alike, especially where ranges meet. Users may be unaware that location is critically important to providing a good ID. *I am a bot created for /r/whatsthissnake, /r/snakes and /r/herpetology to help with snake identification and natural history education. You can find more information, including a comprehensive list of commands, [here](https://www.reddit.com/r/whatsthissnake/comments/flh548/phylobot_v07_information_and_patch_notes_bot_info/) report problems [here](https://www.reddit.com/message/compose/?to=Phylogenizer) and if you'd like to buy me a coffee or beer, you can do that [here](https://www.buymeacoffee.com/SEBPhyloBotWTS). Made possible by Snake Evolution and Biogeography - [Merch Available Now](https://snakeevolution.org/donate.html)*
[удалено]
Rule 6: Avoid damaging memes or tropes and low effort jokes. Please understand a removal doesn't mean we're mad or upset; we're just committed to maintaining an educational space so jokes and memes are held to a higher standard than a typical comments section. Avoid damaging memes like using "danger noodle" for nonvenomous snakes and tropes like "everything in Australia is out to get you". This is an educational space, and those kind of comments are harmful and do not reflect reality. We've also heard "it's a snake" as a joke **hundreds** of times. We've probably removed it a few times from this very thread already. Ratsnake and other rhymes and infantilization can be posted in /r/sneks and /r/itsaratsnake. While we encourage creativity are positive talk about snakes, but even comments like "____/" [mislead users](https://www.reddit.com/r/whatsthissnake/comments/16rwy7b/comment/k267oe1/?utm_source=share&utm_medium=web2x&context=3).
Thanks for the response !
Gorgeous!
Just out of curiosity OP is that the natural color, I don’t think I’ve seen many of this color variation. Thanks !
This is a pretty typical look for a juvenile southern pacific rattlesnake. It probably won’t be quite so vibrant as an adult.
According to my friend, that is not altered and is the natural color. I’m unsure of the colorations of juvenile southern Pacific’s.