Mexican, Sinaloan & Nelson’s Milk Snake Care Guide

In this caresheet I’ll be covering all aspects of care for three different species of Milk Snake, the Mexican Milk Snake, Sinaloan Milk Snake and Nelson’s Milk Snake. These three have very similar care. In fact, you may have trouble identifying them apart by looks, or you may find individuals are cross bred. This caresheet will include housing, heating, lighting, humidity, decor, social needs, breeding and more! Everything you need to know to keep these Milk Snakes as a pet. This information is very similar to keeping other closely related Milk Snakes such as the Pueblan Milk Snake and the Honduran Milk Snake, the main difference being size and looks, so you may want to check out their basic information too before making a decision.

Meet the Mexican Milk Snake

The Mexican Milk Snake (reclassified from Lampropeltis triangulum annulata to Lampropeltis annulata in 2014) is one of the smallest species of Milk Snake, with most adults rarely exceeding two and a half foot, and some smaller individuals may only be one and a half to two feet in length. This makes ideal for those who only have a small space for a habitat.

The Mexican Milk Snake, as the name suggests, comes from Mexico (Coahuila, Tamaulipas and Nuevo Léon), but can also be found nearby in southwest Texas. It comes from grasslands and fields, where it hunts small rodents. With good care in captivity, the lifespan of all three snakes described here is up to or in excess of twenty years.

Sinaloan Milk Snake

The Sinaloan Milk Snake (Lampropeltis triangulum sinaloae) comes from Southwestern Mexico and the areas of Sonora, Sinaloa and Chihuahua. The Sinaloan Milk Snake has larger red bands than other closely related species, because these bands are much larger, the black and white bands are reduced, making it an easier snake to visually identify. The black and white bands themselves are usually around the same width. It is a fairly medium size in the Milk Snake range, reaching from three to four feet, with averages around three and a half foot.

Meet the Nelson’s Milk Snake

Nelson’s Milk Snakes (Lampropeltis triangulum nelsoni) can be found widely across many areas of Mexico and is around the same size as the Sinaloan Milk Snake, with lengths between three and four foot on average. In the Nelson’s Milk Snake the black rings are two to three times the width of the white rings, which are usually quite narrow.

Identifying the three

There are twenty five different subspecies of Milk Snakes that inhabit the same geographic range, most mimic the venomous coral snake, with a black head, then white and black banding, leading to a base red body and bands of black white/cream black. Colours can be very variable between the locality and origin of the species, so judging by colour alone is difficult. Generally speaking an experienced eye should be able identify them by the size and number of banding and some determination may be able to be made by counting scales and comparing, but this isn’t always a guarantee, and it’s very easy for these snakes to interbreed which adds a great deal of confusion. This is why it’s so important in captivity that breeders understand the source of their animals and pass that on. Buy from a reputable reptile shop or direct from the breeder if you want a guaranteed species, as once a snake goes through third parties – especially those who bought the animal as a pet and so didn’t attach any real importance to the exact species or origin – the original information is often forgotten or confused.

I have seen someone told the species of snake they bought from me on one day, and by the next day have already posted a picture in our group with an incorrect label as they misheard or misremembered or misunderstood, so that is how easy it is for information to get mixed up.

Housing

All three species are relatively small, but the Mexican is by far the smallest species.

Mexican Milk Snake – 24x18x18″ or 30x18x18″ as minimum, 36x18x18″ or larger for a spacious home.

Nelson’s and Sinaloan Milk Snake – 36x18x18″ as minimum, 36x24x24″ or 48x18x18″ or larger for a spacious home.

Although there are some glass tanks now available in larger sizes we still prefer wooden vivariums due to their ability to hold heat. If you do decide to use a glass enclosure, ensure your temperature are fully tested in advance as you may need to modify your mesh top to hold more heat in the enclosure.

Heating and Temperature

You need to create a hot and a cold end of your tank for your Milk Snake. This is so they can thermoregulate – choose between hot areas and cold areas depending on their body temperature. All your heating should be on one side of the tank, and this should provide an ambient of 85F – 90F which is 29c to 32c. On the unheated cool side of the tank your ambient temperature should be around 70F – 75F (21c – 23c). At night you can allow this cooler temperature to be steady throughout the tank.

You have two main options of heating:

1. Heat Mat

A heat mat is a device that goes underneath the substrate or against the back wall of a wooden tank. If your tank is made of glass, you can put the heat mat underneath. The heat mat should be well covered by substrate – you do not want your snake to sit directly on it, and should also be kept dry. Heat mats are a more old fashioned method of heating and are not suitable for larger bodied species, but since Milk Snakes are relatively light weight snakes, you can get away with using a heat mat even with an adult.

Your heat mat should always be controlled by a thermostat.

2. Ceramic Bulb

A ceramic bulb is an excellent option for providing heat. It has a much higher heat output than most heat mats, making it more suitable for larger tanks and for obtaining more reliable temperatures. Heating from above is more natural as well. Ceramic bulbs are particularly good for larger snakes or larger enclosures. Your Ceramic Bulb should be controlled by a thermostat and must be guarded so the snake cannot burn itself as well.

Keep a thermometer in the vivarium at all times – digital ones are best – to ensure the temperature is correct.

Humidity & Water

These three species all come from dry areas of scrubland and grassland in Mexico. They do not require high humidity at all – whatever the ambient for your area is should be ample. If they have any problems shedding it’s always a good idea to provide a small moss box with damp sphagnum moss in it, which creates a very localized area of humidity to help them shed. But many milk snakes won’t need this to shed at all.

Milk Snakes will drink from standing water and need a clean, fresh source of water.

Lighting

Having a small daylight bulb in the tank helps provide a natural photoperiod allowing the snake to distinguish clearly between night and day. This isn’t strictly necessary, but it has plenty of benefits and is very inexpensive. You can use a low wattage LED which won’t raise the heat much at all, or you can use a low wattage basking bulb (25w-50w) if you do want to raise the heat a little in this area.

If you use any heat-emitting bulb you will need to put a guard around it to ensure the snake does not curl around the bulb and inflict burns upon itself. Snakes do not recognise pain very quickly and a snake can have horrific burns before it registers to move away.

UVB

In the past people didn’t use UVB for nocturnal species of snakes such as Pueblan Milk Snakes. However, more recent research has shown that most snakes are active at dawn and dusk and will sometimes even bask in full sunlight. UVB has been shown to offer benefits to health, such as increased appetite, more activity and brighter colouration. Following recommendations from Arcadia Reptile, we would recommend having a UV Index of 2-3 in the tank. We recommend you achieve these using the Pro T5 Shadedweller Kit as the most cost effective and well designed product, however you can use a T8 6% if the basking zone is within 10-15″ of the snake, or a T5 6% if your basking zone is within 15-18″ of the snake.

You should use a UVB guard to stop the snake damaging themselves or the bulb.

UVB remains optional when it comes to nocturnal snakes but we highly recommend it. You can read our entire UVB guide here.

Substrate

We recommend Aspen or Lignocel for these Milk Snake species as it’s a dry substrate that allows burrowing and natural behaviour. It’s also possible to use Orchid Bark or other earth-like substrates such as coir, but this is a substrate that does get damper, so we’d recommend drying it out first and making sure that it doesn’t get wet.

Decor

You will want to place at least two hides; one on the hot end and one on the cool end, big enough for your snake to feel secure in and then add decor.

Branches, plants, cork bark – all will give your snake an interesting and natural looking habitat. Milk snakes are active and athletic snakes that whilst primarily terrestrial, will climb and enjoy making the best use of their space.

Social Needs

All members of the Lampropeltis family – that is primarily King Snakes and Milk Snakes – can be cannibalistic. They are particularly cannibalistic as hatchlings, and hatchlings housed together have ended up both dying from one attempting to eat the other. Well fed adults tend not to try to eat other adults, but it can still happen, and they could certainly try to eat smaller individual.

Because of the risks, all King Snakes and Milk Snakes should be housed individually, and only introduced under supervision if necessary for breeding. They have no other social needs and will lead perfectly happy and healthy lives never meeting another snake.

Feeding Pueblan Milk Snakes

Milk Snakes generally have a good appetite and will readily eat defrost mice or rats in captivity. A hatchling will eat a pinkie every 5-7 days, juveniles every 7 days, and adults every 7-14 days depending on their size and needs (breeding females may eat more often). Milk Snakes don’t tend to have the same obesity problems as King Snakes, as their appetites aren’t quite as voracious, but you should be careful not to overfeed. As adults, these three species are all likely to take medium to jumbo mice depending on their size, but are unlikely to grow large enough to move onto rats.

Some captive snakes, accustomed to a ready supply of food that doesn’t walk away can be quite lazy and might prefer to eat overnight at their own leisure.

Handling your Milk Snake

Milk Snakes can be quite nervous as babies, and a little bit prone to rattling or whipping their tail as a threat. This is not an aggressive species and they will usually try to scare off a predator, then flee. There are lots of things that will eat them in the wild! With regular handling, as they grow, Milk Snakes tame down, and an adult Milk Snake is usually calm and easily handleable. They can musk an unpleasant smell if they feel threatened but I find very few adult Milk Snakes do this.

Mexican Milk Snakes in particular have a reputation for being one of the most docile milk snakes, although why this is, no one really knows, but along with their small size, does make them a popular starter snake or snake for children. All of the milk snake family should be calm and handleable as adults and suitable for beginners.

Always support your snake in the bulk of the body and allow them the freedom to explore and climb on you. Wash your hands before and after handling, to avoid your hands smelling like food, and for good hygiene.

Sexing Milk Snakes

Like most snakes, Milk Snakes can be very challenging to determine visually. Both males and females get to roughly the same size, and tail size / length is not a conclusive indicator.

The best way of sexing a Milk Snake is to get an experienced breeder or seller to either pop the hatchling, which involves manually everting the hemipenes, or if the snake is larger, to probe them, which involves inserting a small rod into the hemipenal cavity to count the scales. Both of these methods should only be done by someone experienced.

Unless you are planning to breed, the sex of your Milk Snake really doesn’t matter, as the care is identical for both genders.

Breeding these Milk Snakes

Before you breed, please consider whether your adults are healthy and genetically free of any problems that might be passed down. The female in particular should be fully mature, breeding any snake too early can cause serious health problems. Even the most healthy snake can still have problems during breeding which will need a veterinarian to help with, so make sure you know who your local exotics veterinarian is, and have the funds to take care of any medical needs that might arise from breeding.

You also need to be sure that you can house all your hatchlings separate, get them feeding, and find new homes for them.

Brumation

Brumation happens naturally in the wild. In captivity it’s optional, but if you’re looking to breed then it helps the snake as they would naturally breed in the spring when the weather begins to improve as these are the conditions they need for the eggs to hatch, and their hatchlings to find food. Before brumation ensure that the digestive track is completely empty – don’t feed for at least two to three weeks before reducing the temperature, so stop feeding in mid October.

Around November reduce the temperature to between 55 and 60F. In the UK it can be quite difficult to obtain these low temperatures indoors, so you may need to use an outbuilding that you can keep at a constant temperature. We personally brumate our snakes in our attic with heat mats on thermostats, which enables us to get low and steady temperatures. We brumate for around 3 months, some people prefer to brumate for as little as 6 weeks. The important thing is that the snake understands the seasonal change and thinks spring is here, ready for breeding!

Bring the temperature up to normal and feed after a week of acclimatization. Females should be offered extra food now as they’ll be using all the energy for reproduction.

Courtship and Egg Laying

Introduce the male into the female enclosure if possible. This is because the female gives off pheromones that will be stronger in her tank, especially if she has recently shed. Because this species can be cannibalistic breeding should be supervised. It’s quite common for the male to bite and hold onto the female, this shouldn’t leave any serious injuries, but very occasionally can break the skin. He will line up on top of her and if she is receptive she will lift her tail, copulation may take several hours during which they shouldn’t be disturbed. After copulation they can be separated again. Repeat after a few days to ensure she is gravid.

The female will have a pre-lay shed after approximately 4 weeks. A week after her shed she will begin to look for a good spot to lay her eggs, and a week after that she will lay, so approximately 6 weeks after successful copulation.

You will need to provide a large egg laying box, ample for her to comfortably lay her eggs in. We recommend a small layer of vermiculite at the bottom and then lots of moss, kept slightly damp, but not wet. She will lay between 5 and 15 eggs (with an average of 8 to 10) approximately 6 weeks later. The eggs will probably be stuck together, if so, don’t separate them. Be careful not to turn them as the air bubble is at the top of the egg when laid. Instead, move all of the eggs carefully into your incubator.

It’s possible for a double clutch to occur without a second breeding, you should continue feeding the female well and ensure you keep an eye on her weight and shedding schedule, ensuring the egg box is still available for use.

Incubation and Hatching

We use vermiculite as an incubation media and recommend a professional incubator – but you can use anything as an incubator which holds a steady temperature and humidity. Most incubators are similar to a fridge but instead of a cooler, have a heater.

The eggs will hatch after 60-75 days at 78-80F.

The snake will break their way out of the egg using an egg tooth that drops off after use. They will often sit in the egg with their head out breathing air for several hours, or even several days, as they soak up all of the egg yolk. This is fine and you should let them hatch at their own pace. If it has been 2-3 days after all the other snakes have hatched and there are still a couple of unhatched eggs, you can create a small slit in them and see if the snake inside moves. In this situation, the snake has usually passed away and there are often a few that don’t make it in every clutch.

Babies should immediately be separated into different enclosures to avoid any chance of them attempting to eat each other.

Babies will shed in the first week and then should start to feed readily on defrost pinkies.

I hope that this Milk Snake Caresheet has provided all the information you need to know, but if there’s anything you have a question about just drop it in the comments, leave us an email or contact us on Facebook! We provide free advice on all species of reptiles.

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