Headstarting notes by Kurt Schatzl
This Plymouth Redbelly Turtle Headstart Project page is for present or future participating cooperators, those persons who assist the NEHS and the MDFW in rearing these turtles for release into the wild. Here you will find information on rearing redbelly turtles, expected growth rates, aquarium setup and hints on measuring and weighing your turtles.
Plymouth Redbelly turtles are among the easiest aquatic turtles that I have ever kept. They do eat copious amounts of red leaf and romaine lettuce and produce correspondingly copious amounts of waste that must be filtered adequately. Anyone considering rearing these turtles in cooperation with the NEHS and the Massachusetts Division of Fisheries & Wildlife MUST be prepared to devote a large amount of time to these animals and their care. The following are absolutely essential for the proper maintenance of these animals:
1). A large aquarium or other suitable container that can potentially house a large, basking turtle. The minimum size for an aquarium would be a 20 gallon “long” for a maximum of two hatchling turtles.
2). A submersible heater of appropriate wattage that must be able to heat and stabilize the water temperature to 85 degrees F.
3). A VitaLite or GroLite of appropriate wattage to simulate natural sunlight and UV rays.
4). An uninterrupted source of Red-leaf and Romaine lettuce. I STRONGLY suggest that an arrangement be made with your local supermarket or produce stand to have the “cut-offs” or outer leaves of these brands of lettuce saved for you when the produce people trim the lettuce.
After about three months, it will become increasingly expensive to purchase enough lettuce to maintain these animals and to obtain the necessary gains in weight and size that need to be made in order for these turtles to be released on the specified date after the six-month period has expired. “Short” turtles have to be held over in captivity for a longer time. For example: two two hundred gram turtles (about four months old, possibly less) will consume one head of lettuce PER TURTLE PER DAY under the conditions outlined in the protocol.
This is my Redbelly turtle setup. Note the overflow pipe and drainage into a “sump” consisting of a 10-gallon tank with a power head and undergravel filter which flows into a Fluval canister filter. Utilizing this setup, water changes may be reduced to once per month for the first few months of the turtle’s lives.
This redbelly turtle, number 4725, had an initial measurement of 34.2mm and a weight of 9.02 grams as of 10/18/99. On 11/26/99, a measurement of 52.5mm and a weight of 34 grams was recorded. As you can see, in slightly more than a month’s time, this turtle grew 18.3mm and gained almost 25 grams!
This photo shows the outflow pipe where waste water drains into the sump. A 5/16th hole was drilled into the side of the tank (glass companies will perform this for a very moderate charge) and a pvc pipe was cemented in place. A filter tube cover was cemented over the outflow hole. This is necessary to prevent hatchlings from getting their heads stuck in the hole. I only wish I wasn’t speaking from experience (the turtle in question did survive). Note the subersible heater which is as important as an unlimited supply of romaine lettuce in enabling these turtles to attain sufficient size.
This photo shows the lower half of the main turtle tank and the upper part of the straining pan and “sump,” where waste water drains into the main filtering unit.
This photo shows the waste water drain, the straining pan with window screen and the bio pipe. Note the large particles of waste that the screening has trapped. This screen may be removed for hand cleaning.
This photo shows the main filtering unit consisting of a straining pan using window screen to filter out large particles. Plastic shoe boxes filled with broken bio pipe grow beneficial bacteria and help to break down the turtle’s waste. The ten-gallon tank houses an undergravel filter which further breaks down organic waste. A power head forces water from the sump into the Fluval canister filter, where it is pumped back into the turtle tank as fresh water. The Fluval filter has no filtering medium inside. It is used solely to facilitate water flow into the turtle tank from the sump. The powerhead’s water volume is not sufficient alone.
This photo shows the powerhead filter pumping freshly filtered water into the inflow of the Fluval canister filter.
The inflow pipe from the Fluval canister filter pumping fresh water back into the turtle tank.
Weights, measurements and water temperature are recorded once weekly on the supplied data sheets in the RBT Protocol. Weight gain percentages are calculated by multiplying the “weight change” by 100 and then dividing the new “weight change” figure by the turtle’s “weight in grams.” For example, turtle 4567 has a weight of 240 grams on 10/20/99. On 10/27/99 the turtle weighs 254 grams, a gain of 14 grams, which is the “weight change” figure. multiply this number by 100 , then divide 1400 by 254, which is 5.5118 or %5.5. The turtle has gained five and a half percent since last week.
Turtles are weighed using digital gram scales, since they give a more precise reading and are generally more sensitive than mechanical scales in reading the very small weights of newly hatched turtles. A decent digital scale that reads in tenths of a gram is sufficient and may be purchased at department stores for around forty dollars. the hatchling is placed on the scale after it has been “zeroed” and the weight is then recorded. As the turtles gain size, it becomes necessary to place them in a container to weigh them. The container is placed on the scale, the scale is turned on and automatically “zeroes” itself and then the turtle is placed in the container and the weight is recorded.
Turtles are measured along the straight line of the carapace, from head to tail, not along the curve. A caliper is needed to perform this measurement properly. These can be purchased at hardware stores for a nominal fee.
Many thanks to Jack and Ramona Youngworth for the use of the Sony Digital Mavica camera that was used to produce these photos.