Overwintering Hatchling Turtles-A Headstart

by Chris Bogard ©2005 
 
Every year gravid (females carrying eggs) turtles are hit by cars and don¹t survive their injuries. When a turtle population loses one reproductively mature adult the consequences are considerable and the reason for this is the turtle reproductive strategy which can be described in one word longevity. The ability of individuals to reproduce for 20 or more years insures the continuation of these ancient reptiles. Longevity offsets the obvious disadvantage of high mortality rates for eggs and hatchlings.  The late Dr. Barbara Bonner believed that in a female Box turtle¹s lifetime (50-100+ years) about three of her offspring will survive to adulthood. Losing an adult also means losing that individual¹s genetic information possibly forever if none of her previous offspring has survived.  With the loss of individual genetic information comes the loss of genetic variability for turtle populations. Genetic variability is important in allowing populations to adapt to a changing environment and reduces the chance of inbreeding depression. Negative human impacts could be outpacing the ability of turtles to rebound.  Their continuation is very precarious under these circumstances.  I overwinter hatchlings to increase their chances for survival. By releasing a bigger turtle, certain predators such as crows, smaller marsh birds and fish are more likely to overlook them. When a gravid female dies, her offspring may be the last chance to insure her genes will carry on, which is why I harvest and incubate the eggs of deceased females.  
   The following husbandry and nutritional  information applies only to Painted, Snapping and Musk turtles. The rest of New Hampshire¹s turtle species are either semi-aquatic or terrestrial. These three species listed above require an aquatic habitat with places to hide, UVA/UVB lighting, a basking light and a basking platform to haul themselves out of the water. A brand new hatchling may not eat until most of its yolk sac is absorbed, so don¹t be alarmed if your hatchling doesn¹t eat right away. Rubbermaid containers work best to house turtles in, as they are easy to clean and disinfect. Containers approximately 23"L X 10"W X 9"H work well for a clutch of seven or less. Of course, more containers and fewer turtles per container is even better. One end of the container is propped up about half an inch to provide a shallow end and a deep end. A heat lamp is placed at the deep end directly above the basking platform.  The hide spaces/boxes are placed at the shallow end.  
   Several different materials can be used as hide boxes and platforms. For hide spaces, plastic plants, collard green leaves or plastic trays are acceptable. Plastic plants with thick leaves and stems may prevent nibbling that could lead to GI tract obstruction. Also, rinse thoroughly if brand new. Collard greens from the market are very useful as they provide places to hide under and are edible!! Small plastic trays such as a Lean Cuisine frozen food tray work well. To use these, cut out an entrance and an exit and put two in the enclosure. Turtles, just like your avian and mammal species, need to hide to feel safe. An enclosure with no hiding places is very stressful for them. A 40 or 60-watt bulb is sufficient as a heat lamp. The temperature on the basking platform for Painted turtles (adults and hatchlings) should be around 90-95 degrees Fahrenheit. For Musk and Snapping turtles, it should be around 80-85 degrees. Water temperature should be around 68 degrees. If the water is too warm, your turtles won¹t bask. Baby turtles are very susceptible to respiratory infections if kept too cool/cold.  
   Basking is a very important thermoregulatory mechanism by which turtles keep their digestive, immune and other systems in good working order. It helps to rid them of external/internal parasites and to shed scutes (keratin layer above the bone). Use a thermometer on the basking platform to check the temperature. Remember turtles are ectotherms; their ability to warm and cool themselves is entirely dependent on their environment. For basking platforms, you can use smooth surfaced rocks such as shale. Before use, disinfect the rocks in a dilute bleach solution, rinse well and dry them in the sun. The rocks are set up in a stepping stone manner so the platform is easy to get on and off. Be careful to avoid small gaps between the rocks and between the platform and the sides of the Rubbermaid container. The turtle could go into these gaps headfirst and drown.  
   Most hatchling turtles are more carnivorous than their adult counterparts. However, a diet consisting mainly of protein is insufficient. As no one can be sure of everything a wild turtle eats, a variety of foodstuffs is the best route for a nutritionally balanced diet. Food items rich in calcium are very important and the best sources are greens. Greens and fruit with a 2:1 or better Calcium to Phosphorus ratio can be found on the Internet. Also offer Reptomin, mealworms, crickets and cut up fuzzies. Fuzzies are preferable over pinkies because of increased skeletal material (calcium) and trace elements in the digestive tract. Never feed your turtles (hatchlings or adults) raw or cooked hamburger or bait shop earthworms.  
   When to feed has proven to be almost as important as what they¹re being fed. The reason for this is twofold: turtles will become food fixated and turtles have a preference for protein and sweet (fruit) items. I have received many calls from turtle caretakers telling me their turtle will eat only one or two things. As greens are the least preferred food item, this is offered first along with Reptomin. Make sure the size of the food corresponds to the size of the turtle. For instance, crush the Reptomin into smaller particles for brand new hatchlings. You may have turtles or entire clutches that refuse to eat greens, but alas, I continue to offer it. As the hatchlings get bigger, begin to vary their diet with mealworms, crickets and cut up fuzzies. This is also a diet which is more consistent with what they would find in the wild. Mealworms and crickets should be used with caution as the chitinous exoskeleton is difficult to digest. I don¹t offer mealworms or crickets again until they¹re done passing the exoskeleton. 
   Snapping turtle clutches deserve a special mention because they can become very aggressive as they get older. Keep a close eye on the tail and head looking for signs of biting injuries. The turtle being attacked needs to be removed and housed singularly. Regardless of the species, you should watch all your turtles during mealtime to make sure no one is being bullied away from the food. 
   When spring arrives and it¹s time to release your turtles, the following criteria should be followed. Release the turtles into the body of water the mother came from. You should be able to find appropriate species-specific habitat within _ mile of where the mother was found. Release them into a shallow area such as a cove where there is emergent and submergent vegetation. It is in these areas the turtles will find places to hide, food to eat and the water is warm. Reaching these shallow areas may require the use of a canoe or kayak. Don¹t release more than two or three per site so if a group is lost to predation the entire clutch is not lost. 
   Overwintering/headstarting hatchling turtles increases their chances for survival. Releasing a bigger turtle eliminates some of the predators they would fall prey to as a newly emerged hatchling. This is particularly important if the mother died and her offspring are the last chance to replace her genetic material. Therefore, releasing the hatchlings into the habitat the mother came from is crucial and will require investigation of the area where the turtle was found, knowledge of appropriate habitat for the species you¹re releasing and a good pair of walking shoes.   Happy turtling.