NORTHERN DIAMONDBACK TERRAPIN
(Malaclemys terrapin terrapin)

 

 

DESCRIPTION     SEX     DISTRIBUTION     HABITAT     HOUSING

FEEDING     BREEDING     INCUBATION     HATCHLINGS

  
     

 

 

 

 

 

 

 

 

 

 

 Description: This North American emydid is the sole species that is only found in brackish water habitats. It is quite attractive and several color schemes have been noted. The carapace is strongly keeled along the vertebral scutes especially in youngsters and males. It is also prominent in females but may be worn down with age. Each scute is decorated with concentric rings that can be black, brown, grey, yellow or green. The scutes themselves may appear “diamond like” thus giving the turtle its name, diamondback terrapin. The ground color of the carapace is usually dark and may be shades of brown, grey, cream or tan. Some specimens have a solid black carapace. The plastron is usually a pale yellow but in some instances may be orange, or brown. Black bars, spots or blotches may be present on the plastron especially in hatchlings and juveniles. The head is large mostly in females and is equipped with huge jaws capable of crushing crustaceans. The jaws are so large that when looking at them one may say that the turtle looks as though it is smiling. The eyes may be solid black or may have a brown, yellow or blue-ish iris. Skin color is typically a flat grey and is littered with tiny black flecks and spots or may be pattern less. In very attractive specimens (which are quite common) the skin may be extremely white and exhibit black “tear drop” markings or other designs and the eye lids may be a faint blue. These beautiful examples of Malaclemys terrapin terrapin are highly sought after and are referred to as “concentrics” due to the stunning design of the concentric rings on the carapace. Diamondbacks have powerful and large hind legs which allow them to be great swimmers in the deepest of water ways. Both hind and front legs sport sharp claws that aid them in digging through thick mud, ripping apart food items, and constructing nests. They also enable the animals to haul themselves out onto a snag, log or other floating debris. In some specimens a sharp diamond figure is visible on the top of the head just between the two eyes and is usually black in coloration. These turtles can grow quite large with females reaching nine inches and more. Males however, are smaller animals usually only reaching four to five inches.  
Sex: Sexual dimorphism in Malaclemys terrapin is extremely conspicuous with males being literally half the size of females. They may seem even smaller depending on the dimensions of a particular female. Many males never surpass five inches while most females I have observed are usually well over eight inches. Of course like most chelonians there are larger and smaller individuals of both sexes recorded. Males also have very long, thick tails while females exhibit short, stubby tails only thickening at the vent. As stated previously, females may have extremely large heads while males feature smaller more proportionate heads. Males do not usually have a concave plastron like many other chelonians do.  
Distribution: Northern Diamondback terrapins are found all along the east coast from Cape Cod Massachusetts, to Cape Hatteras North Carolina. Terrapins found in Maryland and in the Chesapeake Bay are sometimes referred to as “Chesapeakes”.  
Habitat: Malaclemys terrapin terrapin is found in a wide variety of brackish water habitats. Tidal pools and creeks, estuaries, coastal marshes, and bays are common places to see wild terrapins and rarely one may be spotted in the ocean along beaches. They are full-time inhabitants of the salt marsh ecosystem and only occasionally share their homes with other turtles. Northern red-bellied, spotted, common snapping and eastern mud turtles have been known to live along side of diamondbacks in brackish conditions but this has only been noted in a few localities. The marshes and other tidal waters are well equipped with deep, thick mud, plenty of vegetation and tall reed grasses. This is where the terrapins find food and refuge.  
Housing: Terrapins should be housed outdoors whenever possible and where weather conditions are suitable. These turtles come from the northeast where they spend the warm months hunting for food and basking in natural sunlight and remain buried deep in the mud for the winter. An outdoor pond well protected from predators and thieves is suggested so that the animals can enjoy a little piece of nature and have access to plenty of unfiltered sunlight. A large baby pool or Rubbermaid stock tank will provide a simple enclosure for a pair of terrapins and is easy to clean.

If you plan on keeping diamondbacks indoors, a large well filtered aquarium or Rubbermaid is best. Females especially will attain rather large dimensions and will need appropriate housing conditions with as much space as possible. A 55 gallon all glass aquarium works well but should really only be used for one female, maybe a pair. UVA/UVB emitting bulbs are needed as well as a strong basking platform of some sort so that the turtles can completely dry off and benefit from them. Remember to get your hands on a reliable filtration system to be able to handle all that water.

Because diamondback terrapins come from brackish water it can prove to be extremely difficult to introduce them to fresh water in captivity. I strongly suggest that you obtain captive bred hatchlings and juveniles that have been born into fresh water. Adults coming from brackish habitats can be switched over but the success rate is low and trying this can result in the death of the animal. I also advise that you keep store bought marine salt handy at all times and mix a small amount in with your terrapin’s water. Diamondbacks of all ages are prone to skin infections and keeping a bit of marine or sea salt in the water will help to prevent that from happening.

  
  Feeding:  In the wild these turtles feed on various crustaceans, mollusks, and fish. Fiddler crabs and snails such as periwinkles are favored by the adults and insect larvae or tiny new born snails may be taken by hatchlings. In captivity I have found that if you start hatchlings right off the bat with a variety of foods, you will have very few problems down the line. Baby terrapins that are fed only one food item for a very long time become fixed on it. It can be very tricky to switch them over to other food items they are not used to. Hatchlings will usually readily accept commercial foods such as Tetra Reptomin but should also be offered shrimp, clams, snails and various fishes. Adults that have not been fed commercial diets previously in their lives will usually feed well on fiddler crabs, salted and unsalted clams, shrimp and some fish. Some adults may even take chicken. These turtles are for the most part entirely carnivorous and I have never witnessed one consume a fruit or vegetable in captivity.  
  Breeding:  Northern Diamondback terrapins breed immediately following their emergence from hibernation in the wild. The male swims after the female, sometimes biting at her and he rubs his tail against hers. Once the female cooperates he will float at a ninety degree angle behind her and begin copulation. The male may also lie backwards facing away from the female while mating goes on.

Females begin to leave the safety of their watery homes in June but sometimes as early as late May in search of proper nesting grounds. A warm, sunny day with a temperature between 85 and 95 degrees Fahrenheit is what usually brings the females onto land to nest. I have observed that the majority of nesting occurs in the morning between the hours of 9:00am and 11:30am but may continue on throughout the day and into the night. Depending on the habitat they live in and what surrounds it will determine where they lay and how far they will have to travel to do it. Many major roads cut right through coastal marshes and this forces the females to cross them. Every year hundreds of female terrapins are killed by vehicles during their attempts to cross busy roads. Females usually seek out sandy dunes, hills or roads that receive plenty of sunlight for oviposition. In captivity a sandy beach or south facing slope is appropriate for nesting in an outdoor enclosure. Indoors a large Rubbermaid container eight to twelve inches deep filled with 50% play sand and 50% potting soil works best. Be sure to keep a spot light six to eight inches just above the nesting container and make entrance into it easy. The turtles will first clear the area they have chosen of any debris and begin digging a flask shaped nest with both hind feet. I have observed several nesting terrapins both in my home and in the wild and I must say that I have noticed that these turtles nest quicker than most others. Many species of North American emydids may take hours to construct a nest and deposit their eggs while terrapins get right down to business once they have chosen a suitable spot. This of course is only what I have observed and others may have different notes. Females lay anywhere from 6 to 15 eggs depending on the individual turtle but usually the number is between 8 and 12. Once she has finished laying, she will cover the nest and head back to the water. Many females lay a second clutch of eggs just fourteen days after the first.

 
  Incubation: Once your females have finished nesting remove the eggs and place each individual clutch into separate deli cups or Tupperware containers on a substrate of moistened vermiculite. Perlite, sand, soil and sphagnum moss also works well but vermiculite tends to retain more moisture and it is important that terrapin eggs do not dry out. Be sure to poke several holes into the lids of the containers to allow proper ventilation .Hovabators make wonderful incubators and can be purchased at many feed and pet sores. Do not turn the eggs during incubation to avoid killing the growing embryo. At about 86 degrees Fahrenheit, the baby terrapins will merge from their eggs anywhere between 40 and 60 days. The hatchlings usually measure about one inch but may be smaller or larger depending on egg size. For the first few days of their lives, the baby terrapins will use their yolk sacs that are still attached as their food source. Once the yolk sac has been completely absorbed they will begin feeding regularly.  
  Hatchlings: Hatchling Malaclemys terrapin are for the most strong swimmers right out of the egg however, caution should be taken so that the babies do not drown. I recommend setting them up separately in 10 gallon all glass aquariums or in Rubbermaids with two to four inches of water a small basking area and a source of UVA/UVB. Depending on the temperature of the room you keep them in will determine if you need a submersible water heater. The reason I suggest keeping hatchlings individually is because injuries are all too common with raising diamondbacks. These are very active and aggressive turtles and tank mates will bite at each other’s feet and tails. Tail nips usually heal well as long as the cloacal region has not been harmed but foot bites can quickly escalade into major infections. Raising them alone until they have reached a less vulnerable size is highly optional but is entirely worth it. Baby terrapins grow fast and can attain a good size within their first year. Do not raise hatchling terrapins outside until they have reached at least four inches unless you can completely protect them from birds and other predators.  
 


 CHRIS LEONE