Captive Crocodilian Suggested Best Management Practices (BMPs)

The order of reptiles known as Crocodilia, which currently include 23 living, or extant species, consist of the crocodiles, alligators, caimen, and gharials, or gavials, are also commonly referred to as “crocodilians”, collectively. Medium sized, to large, solidly built animals, crocodilians have remained relatively unchanged for millions of years ever since our modern order of these highly successful animals first appeared approximately 90 million years ago, with their earlier ancestors dating back even further, with some members first appearing 250-some million years ago during the early Triassic period! They are also among the next closest living relatives to birds, possessing four chambered hearts similar to those of birds, as well as numerous other adaptations having made them successful! Well adapted for life both on land and in the water, different species of crocodilians are found throughout the world on all continents except Anterctica and perhaps Europe in tropical to sub-tropical environments, and have all evolved their sometimes own unique methods of locomotion, feeding and dietary habits, circulatory, respiratory and thermoregulatory behaviors and systems.

They have also evolved some of the most unique parental and nesting behaviors among any reptiles or amphibians, often providing direct parental care to their eggs and young for periods of time prior to the hatchlings becoming independent. These reptiles have furthermore evolved to develop among the most advanced and sophisticated means of communication and different forms of vocalizations among the reptiles. They also can play numerous other unique ecological roles, or niches as well, such as their nesting mounds providing nesting sites and shelter for other species, as well as their ability to modify some wetland habitats in some areas of the world to provide hospitable habitats for other species as well during times of drought or dry seasons, such as in the Florida Everglades.

Throughout the world, humans and civilizations have also been influenced in innumerable ways by crocodilians. While predatory attacks on humans and pets, and other conflicts between humans and these animals are unfortunately well-known and documented, they nonetheless are also culturally depicted in many different forms of religion, mythology, and folklore or literature, and also face many conservation concerns throughout the world, namely over-harvesting or over-hunting, poaching, and habitat loss and destruction. Some species of crocodilians, especially, have become among some of the most threatened and imperiled species of reptiles due to these threats.

When it comes to herpetoculture (or the breeding and keeping of reptiles and amphibians in captivity) and the pet trade, several species are kept and are available. Despite this, and rather obviously, crocodilians as a whole make for far from being suitable pet reptile species, and indeed, only very small segments of the overall reptile and pet keeping communities should be, or are able to properly house and care for these animals throughout their lives. While hatchlings especially can undoubtedly be cute, tempting, and appealing to maintain initially, and with some species being initially inexpensive to purchase (most notably baby American alligators, Alligator mississippiensis), they have the potential of growing very quickly. These animals can quickly become very large, very strong and powerful, and potentially dangerous, and can also become very difficult and expensive to properly feed and maintain. Nonetheless, serious and dedicated individuals of these animals, whether amongst the public or private sectors do exist, and must be recognized through the establishment of the following suggested best management guidelines and protocols for crocodilians.


-Laws and Legalities. Regardless of whether they make good pets or not, crocodilians should only be kept in areas where it is legal to do so, or otherwise under the appropriate licenses or permits, should they be required. Many states, counties, and local municipalities outright prohibit or strictly regulate the ownership of these species, or otherwise have size limits in place. Not keeping these animals in compliance with all local, state, or sometimes even federal laws, regulations, and ordinances places oneself at greater risk in the event of an accident, the animal’s well-being, and gives additional black eyes to the reptile and exotic pet communities.

-Facilities Maintenance and Management. Consider the other facilities maintenance and management aspects to keeping crocodilians. All floors and floor space within and around the room(s), or areas, in which crocodilians are maintained should be kept clean and sanitary, free of any unnecessary obstructions or other debris and clutter which may impede quick and/or evasive movements should they be necessary. Any and all potential or accidental falling, slipping, or tripping hazards should be reduced as much as possible or eliminated. Also consider all other emergency preparedness procedures, and plan ahead accordingly, including in the events of storms, fires, floods, or other natural disasters which may prolong access to proper medical attention should a bite or other accident occur during these conditions. The last thing any crocodilian owner or keeper wants are for there to be further delays in accessing medical treatment or intervention in the event of an accident. Prospective crocodilian keepers and owners should also have emergency backup lighting and generators in the event of a power outage, as well as a longer term plan with qualified emergency contacts in the event of the absolute worst case scenarios requiring these animals to be temporarily re-housed and/or cared for under such circumstances.

-Transport and Temporary Containment. Temporary containers, crates or boxes, and other enclosures for the purposes of temporarily moving or transporting crocodilians to and from enclosures for regular, or routine maintenance, or for shipping should also consist of a sturdy, quality, escape-proof material and be lockable, or otherwise latched. All containers or temporary enclosures an animal may be housed within for the purposes of sale, exhibition, or shipping and transport should ideally be sealed and escape proof. All crates, boxes, and shipping containers should also be labelled with the species (genus and species), sex, quantity/number of animals enclosed, and all applicable contact information for the seller/owner, and receiver and any other relevant information. All animals, containers or enclosures housing a crocodilian must either be otherwise be contained in a rigid secondary display case or have adequate barriers preventing the unauthorized handling of any containers or enclosures or escape of animals.

-Feeding and Accessing the Enclosure. Only authorized and qualified individuals should have access to, or the ability to open and service a crocodilian enclosure, or otherwise be able to access the secondary enclosure (i.e. room or facility in which the crocodilian(s) are being maintained). Appropriate tools should always be suggested in opening a crocodilian enclosure, rather than by bare hands or fingers, unless an otherwise suitable, clear and transparent barrier still exists between the individual and the animal. Always ensure that the animal’s whereabouts in the enclosure are known prior to servicing the enclosure.

-Most species of crocodilians are very eager and opportunistic feeders, which make for especially potentially dangerous conditions when handling or working around these animals. Most crocodilians have excellent vision, and also rely on scent to detect warm-blooded, or endothermic prey. Many accidents and mishaps have occurred when attempting to feed crocodilians, and not following adequate feeding protocols are perhaps one of the most common scenarios which can be avoided. Do not handle or approach a crocodilian if one has recently and previously handled or come into contact with any such endothermic animals, whether alive or dead, or if any of these animals are also housed nearby or in the vicinity, such as dogs, cats, birds, rodents, or rabbits and other small mammals. Frozen-thawed, or pre-killed prey items should also not be provided by hand; instead use the appropriate length of tongs, forceps, or hemostats and other equipment to provide food at a safe distance. Always wash one’s hands with soap and water prior to handling or interacting with a crocodilian in order to remove any potential scent of prey and possibility of a feeding related mishap.

-Written and Printed Protocols, BMPs, Emergency Contacts, and Other Information on Hand. Emergency bite protocols, procedures, and best-management practices for crocodilians being maintained should be readily available and accessible. While they do not need to contain much of the information which would be more relevant to a venomous snakebite or mishap, or necessarily be specific to each individual animal, having at least a written plan and protocols in place for the event of a feeding or handling related accident, as well as an escape recovery plan, should be recommended as protocols for any crocodilian species.

-Handling and Restraint of Crocodilians. Crocodilians in general are very seldom the first animals that come to mind for most when it comes to handling and handle ability. For reasons that should be obvious, they can be potentially dangerous animals to handle and work with if proper safety and handling protocols are not followed and practiced. Crocodilians are animals that should not be underestimated when it comes to their speed and strength, as they can be very strong and powerful animals. Even a small crocodilian at 2 (two) feet or less has the potential of inflicting a nasty bite requiring stitches and/or medical attention. As such, a disclaimer should be included here that handling, or attempting to handle any crocodilian species should not be attempted by those inexperienced and unfamiliar in doing so. These animals do not make suitable pets for all but the most dedicated and experienced facilities and few private keepers and hobbyists. There is also some variability in the dispositions of these animals depending on their age, size, species of crocodilian, and even among individual animals. American alligators (Alligator mississippiensis), for example, tend to be the most docile crocodilian species at least relatively speaking, but are also a large species that still can be quite difficult and potentially dangerous to handle, particularly for one person.

-While some of the dwarf caimens can become somewhat tame and handleable, they are a shyer and more secretive species and reports of their dispositions and temperaments vary, and as stated previously, each animal is an individual.

-There is also the question of whether these animals should be handled. This depends largely upon the specific purpose for keeping the animal. If an animal is being maintained primarily for purposes of display or exhibition, then handling is typically less of a priority. If one does choose to handle their animal, then it should be initiated at as young and early of a stage as possible. The best likelihood of ending up with a relatively tame animal, or at least one that is otherwise accustomed to handling, being around people, and routine activities such as feeding and cage cleaning is to start at the hatchling stage. Larger and/or older animals tend to be far more difficult, if not impossible to safely be acclimated to handling if not initiated previously. Many juvenile and hatchling crocodilian species may emit a bark-like “yelp” when handled or distressed. This is a natural vocalization intended as an alert or warning to a would be parent animal that the young animal is in distress.

-The best methods for handling these animals of course depends on the size of the animal. Juvenile and hatchling animals should be handled for at least several minutes each day, although they should not be over-handled in order to prevent undue stress to the animal. Hatchlings can be gently and carefully scooped up from underneath and be gently restrained in the palm of the hand. It is important to not to overly restrain an animal in order to prevent further stress and possible injury to either the handler or animal. If the hatchling attempts to bite, further restraint can be made with the fore finger and thumb over the animal’s neck and shoulders. Relatively small animals up to about 2 to 3 feet in length can usually be handled safely using one fore arm to adequately support the animal’s body, and the tail pinned between the handler’s body and arm to prevent excess movement. Older or slightly larger animals that cannot be held using one hand and arm can be held with two hands, one securely behind the neck, and other around the pelvic girdle and hind limbs or base of the tail. It is never advisable to lift or attempt to handle a crocodilian by their tail alone, for they are also very flexible animals that can very easily and quickly turn around to bite.

-The use of gloves to handle crocodilians? Work gloves can be used to handle or restrain hatchling and smaller crocodilian specimens if one chooses to use them, but they can oftentimes reduce dexterity and precision, particularly when gentler handling is required. Furthermore, gloves will not withstand or protect one from the bite of larger and more powerful animals that are substantially larger than 2 or 3 feet in size or length.

-When it comes to animals that are four (4) to five (5) feet or larger, handling becomes much more impractical in the context of picking them up. Most crocodilians at or exceeding this size range are too large, heavy, and/or potentially dangerous to handle alone or without the assistance of at minimum a second person on hand. Larger and older animals should obviously be approached with safety in mind using a specifically designed safety and capture noose or catch pole to first secure the animal’s head and jaws while a second or even third person secures or restrains the animal. In order to coax an animal to move or be transferred, the use of a suitable object, such as a broom, long wooden pole, wooden shield, or other portable barrier. These devices should not be overly hard in order to prevent tooth and mouth injuries should the animal bite down on them.

-Crocodilians are generally known for having among the most powerful downward bites among animals. However, their same musculature required to open their jaws is very weak and can usually be easily held shut using a proper device including but not limited to an elastic band or adequate strength, masking or duct tape, a soft rope or twine, or other fabric that is not abrasive or harms the animal particularly when removing it from the animal. It is also important to remember that when securing the animal’s jaws, that their nostrils at the tip of the snout are not covered, which could otherwise inhibit the animal’s breathing. There are overall many different capture and restraint techniques that can be employed on mid-sized to larger crocodilians that are beyond the scope of this care sheet. In order to learn more about these, it is always strongly encouraged to anyone with an interest in responsibly keeping these animals to not only read and consult further sources of information, but, more importantly, gain additional hands on first experience from a qualified and well versed zoological facility, veterinarian, experienced private keeper, or other individual or organization with similar, comparable knowledge and experience.

-Primary Enclosures and Housing of Crocodilians. Housing and appropriate setups are perhaps the most challenging factor in maintaining any crocodilian species, and is a factor which greatly limits their suitability as pets. Many factors should be considered when it comes to housing these animals, including the species being maintained, their growth rates, the size and space required for an appropriately sized enclosure, cleaning and routine maintenance, and short term and long term housing costs. Crocodilians in general are semi-aquatic animals, and will require the appropriate amount of square footage in both water and dry land space for basking, thermoregulation, feeding, and foraging. The amount of water to land ratio provided in the enclosure will oftentimes vary considerably depending on the age, size, and species being maintained. The amount of water that should be provided, and the amount of time the animal will spend in it also will vary depending on many factors. In most crocodilian enclosures and setups, a water area should be wide and deep enough for the animal to enter and submerge itself completely in as well as be able to easily turn and move or swim within the area.

-Most crocodilian species will require a water area of at least 70 to 80% of the enclosure, although as previously mentioned, the dwarf caimans can be more terrestrial, with an allocated amount of 50 to 60% of the enclosure being aquatic. The amount of time an animal spends in the water depends on several factors including the water’s temperature (if the water is too cold, they will spend more time out of it basking and vice versa), whether a proper enclosure and setup with adequate hiding opportunities is provided, as well as the animal’s safety and stress levels. Although some crocodilians can tolerate saline water conditions, the dwarf caiman does not naturally occur in these conditions, and freshwater should be used for these species. At a minimum, the amount of heated land area provided should be enough to allow the animal to completely emerge from and bask out of the water, and be at least twice the animal’s length in order to allow it to walk, easily turn around, or move about freely out of the water.

-Crocodilians can be housed communally, or with certain other animals, but this of course depends on many factors include the relative sizes, species, and biology of the animals being considered. Generally, there should never be any significant size disparities between animals. Crocodilians can be quite cannibalistic, and will kill and/or eat significantly smaller turtles or other crocodilians (even if they are the same species) if perceived as food or in territorial disputes. Likewise, very large, predatory fish or turtles will eat a hatchling or small crocodilian if provided the opportunity. Even similar sized turtles or other species may still nip one another if adequate food and space for both are not provided. Generally, the safest and best practice is simply to house crocodilians separately from any other animals.
The enclosure itself should be secure, sturdily built or constructed, be adequately ventilated, and escape proof. As with other reptiles, crocodilians can be surprising escape artists if the enclosure is poorly designed. Most species of crocodilians, and especially the dwarf caiman species, are surprisingly good climbers, jumpers, and burrowers that can also easily burrow underneath barriers or fences if the enclosure’s foundations are not deep or sturdily built enough. Any furnishings in the enclosure should also not be able to provide access for escape.

-The actual size of the enclosure depends on the age, size, and species being maintained. In general, however, an enclosure should be at a minimum 3 to 4 times the length of the animal in width and length. Some standards, such as those adopted in Germany (but not yet the U.S., although they may certainly be used and applied elsewhere), for example, indicate that a minimum amount of land space should be 3 times the animal’s SVL (snout to vent length) wide and 4 times in length, and the minimum aquatic area at least 4 times the animal’s SVL in width, 5 times their SVL in length, and at least a third of that animal’s SVL in depth. Hatchling to juvenile crocodilians of most species, including the dwarf caimans, can be started off in an appropriately sized glass or wood sealed 20 to 40 gallon aquarium or terrarium, although they will soon outgrow these quarters. Glass aquariums and terrariums are almost never suitable enclosures or setups for maintaining sub-adult to adult crocodilians in, and they will instead require custom designed enclosures designed from plastic, wood, concrete, and/or fiberglass. Unfortunately, there are not currently any suitable commercially or readily available enclosures designed specifically for crocodilians as there are for snakes, lizards, and many other reptiles. However, some of the large prefabricated enclosures available in a variety of shapes, sizes, and dimensions such as galvanized steel or plastic troughs used in aquaculture and other agricultural uses can house at least hatchling to small sub-adults of some crocodilian species but are still not suitable enclosures for any larger animals. Substrates such as aquarium gravel or rocks can be used, but excess ingestion of them should be avoided or prevented. Many other furnishings in a crocodilian’s enclosure may be destroyed or uprooted if they are not firmly planted or secured.

-Additional furnishings and décor can also be provided in the enclosure, but should be so that they are easily removed and replaced when cleaning or servicing an enclosure, and do not injure or impede either the animal in its enclosure, or access to or within the enclosure. As it can be imagined, crocodilians can also be very messy animals to maintain, and the water as well as enclosure should be kept clean and adequately filtrated for quality and clarity as much as possible. Regular maintenance should include daily spot cleaning and removing of any wastes or uneaten food, as well as using an appropriate filtration and pump system (there are many different products, options, and configurations available), aquarium gravel and under tank gravel filtration systems for sifting debris caught in the substrate, and other bacterial and aerobic systems that can assist in breaking down and dissipating harmful chemicals or sediments such as ammonia.

-Some testing kits are also available that can test and monitor water quality and ammonia levels as well. And while an effective filtration system(s) can be greatly beneficial in keeping an enclosure clean and sanitary, complete water changes will still need to be made at least once every week to two weeks (smaller enclosures can be easily changed daily) and the enclosure and any furnishings will need to be removed, scrubbed, cleaned, and disinfected with an antibacterial agent thoroughly. Depending on the enclosure and the setup, larger enclosures can be equipped with a siphoning and/or drainage system to more easily change and replace the water regularly. The overall frequency of cleaning an enclosure depends on the type and strength of filtration system being used, the animal’s feeding regime, and how often spot cleaning and other maintenance is performed. In addition, cleaning to a large extent, is dependent on the particular setup and circumstances.