Beyond providing excellent care for the institution’s collection, Lincoln Park Zoo’s veterinary staff also conducts research to advance the science of veterinary medicine. Read on to get a closer look at ongoing veterinary research projects.
Shell Mineral Composition of Artificially and Naturally Incubated Ornate Box Turtle Eggs
Ornate box turtles (Terrapene ornata ornata) are native to sand prairies in the Midwest and are currently listed as a threatened species in Illinois. The U.S. Fish and Wildlife Service (USFWS) has established a program to increase the population by transporting ornate box turtle eggs from their unguarded nesting sites to local zoos. At these facilities, such as Lincoln Park Zoo, these eggs are protected and incubated to produce hatchlings, which grow for the first year—their most vulnerable time of life—before being released into the wild.
With grant support from both USFWS and Association of Reptile and Amphibian Veterinarians, Lincoln Park Zoo’s Associate Veterinarian Kristina Delaski, D.V.M., helped scientists in the recovery program by identifying differences in the mineral composition of eggshells from nests hatching in the wild and those in the zoo. Shells were analyzed by spectroscopy to obtain measurements for calcium, phosphorus, magnesium, potassium, sodium, sulfur, copper, iron, zinc, manganese, molybdenum and cobalt content.
The results showed a wide range of variability in mineral content, with significant differences in nearly all minerals analyzed. In fact, the only mineral that was not different between naturally and artificially hatched eggs was sulfur. It is not yet known whether any of these differences are relevant for hatching success. However, future studies can now aim to investigate this question and identify differences between shells from fertile and infertile eggs and successful and unsuccessful hatches.