Notes on the Life History of the Mud Snake

Abstract

DURING the latter part of June, 1938, an exceptionally beautiful and heavy bodied specimen of the mud-snake, Farancia abacura abacura Holbrook, 56 inches long, was received at the Toledo Zoological Park. The snake was placed in a cage containing a large pool of water and kept under observation in the hope of observing egg-laying. Meade (1937: 12) reported on the breeding habits of the snake in captivity and in other publications on the egg laying (1935: 190), maternal care of eggs (1940: 15), feeding habits (1934: 91) and hibernation in captivity (1935: 99); Goldstein (1941) has reported collecting eggs in the field in Florida. Early in the morning of July 9 the mud-snake crawled from the water to the rocks above the pool and appeared to be nervous and in search of a suitable place to deposit her eggs, finally coiling in a level spot some 2 feet directly behind and above the pool. On the following morning several eggs were observed beneath her coils. When the cage was opened the snake paid no attention to the intruder. She was left coiled about her eggs until the next morning, July 11, when it was found that she had left the clutch and was moving about the cage. The eggs were then removed and found to number fifty-four. The eggs were not adherent, white in color, elliptical in shape, and with shells of a smooth, leathery texture. The average weight per egg of thirty that were weighed was 12.3 grams. A large glass container was filled with moist sand, and ten of the eggs were buried about one half inch below the surface of the sand in the container. The jar was then placed in a sun incubator, and the eggs were kept as near the original degree of dampness as possible by daily sprinkling, at 72? to 75? F. The first examination of the buried eggs was made on July 21. Because the shells were slightly discolored and very tight, it was thought that the eggs were probably too damp, and the sprinkling was reduced to once or twice a week. An egg taken from the container and opened on July 27 was found to contain a live embryo, but apparently the eggs were still too moist, and less water was added during further sprinklings. Three of the eggs had spoiled by this time. Another egg examined on August 10 contained a live, fairly well developed embryo. The tail was firmly attached to the trunk and the pulsations of the heart could be seen distinctly. At the same time another spoiled egg was found and removed. An egg opened on the morning of September 7 contained an embryo ready to hatch. The embryo was weak and died during examination. The three remaining eggs were then placed in a vivarium prepared from an aquarium tank. The bottom was covered with approximately 2 inches of fine sand and a shallow water pan was buried in the sand at one end so that its top was flush with the surface of the sand. Leaves were scattered about the floor to furnish hiding places for the young snakes.