Elaphe Obsoleta or Pantherophis obsoletus? Or for people in my neck of the woods.... The black snake!
For people in the United States, this is easily one of the most common snakes around. Everyone has a slew of stories about the eight foot long black snake they ran in to. The names most commonly associated with this snake are black snake, black rat snake, Texas rat snake, chicken snake, and pilot snake, What's interesting however is that there is more than one type of black snake in the United States. There are actually three separate species of black snake, though to those of us untrained in the field of herpetology could probably not tell them apart. In areas where the species cross each others paths they even breed. The other two species are the eastern rat snake and central rat snake. They do have some DNA differences but for all practical purposes they are pretty much the same snake and can each be easily referred as any of the common names listed above.
The reason for the two scientific names above with the question mark is because of the debate associated with their names. All three species' scientific names originally started with the word 'elaphe'; elaphe obsoleta (western rat snake), elaphe alleghaniensis (eastern rat snake), and elaphe spiloides (central rat snake). In the early 2000s a scientists proposed that pantherophis was a more appropriate title. More researchers followed up on the work and determined the same thing. So now it is commonly accepted that the name be pantherophis. Pantherophis obsoletus (western rat snake), pantherophis alleghaniensis (eastern rat snake), and pantherophis spiloides (central rat snake). Despite the fact these names are now commonly accepted, the problem is that for it to be official the International Commission on Zoological Nomenclature has to agree and approve it. For whatever reason they have not jumped on board with the name change. Despite all of the scientific silliness over the name, any old farmer will tell you plain and simple it's a black snake.
In case you didn't know, this snake which is possibly most well known as the black snake is in fact black. The top half is anyway. From a distance they will typically appear to be a solid shiny black color or a dark gray. If you get up close however, you can sometimes make out a bit of a pattern. Possibly some dark brown spots or red on the side. The belly of the snake is generally white or may have a very light yellow tint to it. The belly may also have random blotches of black or gray in random patches.
The western rat snake looks completely different when it's a baby however. It will be a tan or gray color with a pattern of big brown blotches running down it's back and sides. The occasional dark brown spots you might see on an adult are the spots where the color didn't completely change to black from when they were kids.
The western rat snake currently holds the record for the longest snake in the United States, though that is more of a technicality as bigger snakes of other species have been found, but aren't on the record books for whatever reason. The current record is 8 foot and 4 inches. While 8 foot western rat snakes aren't completely uncommon (I've seen a few myself that were probably close), it's much more common to see an adult western rat snake be 3 to 6 foot long out in the wild.
The western rat snake spans a vast area from the eastern United States to central United States. From the southern areas of the United States and as far north as Canada.
The western blacksnake is a woodland creature, but they don't have to many reservations about where they hang out. If they can find a food source and a decent climate you can expect to find them. Yes... This includes your house. Rat snakes are one of, if not the most common snake to find in one's home. Human homes offer great hiding places and a controlled climate. Throw in a few field mice running through the cupboards and you have a perfect place to share with a big black western rat snake. Black snakes can be found hanging out in all kinds of places from forests, to farms, to your attic. They like to climb trees too.
The western rat snake is an equal opportunity predator. They aren't overly particular about their food as long as it's warm and living including rodents, reptiles, amphibians, birds, eggs, etc.. They are powerful constrictors and the big ones have even been known to take down rabbits and squirrels. Most farmers love having big black snakes around because they do more to safely control rodent populations than anything the farmer can do themselves.
I've known a lot of people to have the common misconception that black rat snakes and king snakes are the same thing and proudly stroll through the world ridding it of evil venomous snakes. This isn't true. I can't honestly say whether a western rat snake would attack a venomous snake or not. I also can't tell you with certainty that they are immune to their venom. However I can tell you that venomous snakes aren't generally a large part of the western rat snake diet. In fact the western rat snake will often share a den with copperheads and rattlesnakes during the winter months. The nickname pilot snake actually comes from a myth that says the rat snakes come of the den early, to ensure the area is safe for rattlesnakes. Another myth is that black rat snakes will breed with rattlesnakes or copperheads creating huge hybrid venomous snakes. This also is not true. For one, they aren't the same species and to put it simply, their DNA's won't match up. Also if this was even remotely true there would be documented cases of it; which there isn't
Interactions with humans
The western black snake is well known for having a sassy attitude toward people. The reality is that if a person leaves the snake alone, it probably won't bother them. Like most snakes the western rat snake will try to flee when it can. If fleeing isn't an option it will smack it's tail against the ground to mimic a rattlesnake. It will also release a smelly musk to make would be predators think it isn't safe for eating. When further antagonized the western rat snake will strike. It is nonvenomous and considered harmless, however a six foot long snake can have a mean punch. I've learned this lesson first hand. I can personally tell you that they can be very aggressive in the wild.
When I was a child my family ran a large business. My uncle was talking to a group of around thirty people in front of a wagon. I happened to walking on the back side of the wagon and noticed a very large black rat snake stretched across the wagon. I quickly interrupted my uncle and pulled him off to the side. I told him about the snake and we came up with a plan. He would take the group to another area and I would remove the snake before they returned. Sounds easy right? I threw on a pair of leather gloves and attempted to gently pick up the snake. The six foot black snake was having none of it. It snapped on to the gloved hand like a vice grip. It let go on it's own and started going for the face. I decided to give the snake some space, and he disappeared on his own.
Of course they aren't all hostile toward people. I've picked them up and played with them before when I was a child. Some species of snakes tend to have unique personalities, and in my opinion the western rat snake is one of them. It's also worth noting that rat snakes have become a popular pet. Like most creatures, western rat snakes born and raised in captivity tend to be much more docile than those in the wild.
nick on March 08, 2013: