Nest temperature, incubation time, hatching, and emergence in the Hilaire's side-necked turtle

Published source details Bujes C.S. & Varrastro L. (2009) Nest temperature, incubation time, hatching, and emergence in the Hilaire's side-necked turtle. Herpetological Conservation and Biology, 4, 306-312.
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This study is summarised as evidence for the following.

	Action	Category
	Relocate nests/eggs for artificial incubation: Tortoises, terrapins, side-necked & softshell turtles Action Link

Relocate nests/eggs for artificial incubation: Tortoises, terrapins, side-necked & softshell turtles

A replicated, randomized, controlled study in 2004–2005 on one grassy bank of a river delta in Rio Grande do Sul state, Brazil (Bujes & Varrastro 2009) found that artificially incubating Hilaire’s side-necked turtle Phrynops hilarii eggs resulted in higher hatching success and larger hatchlings compared to eggs incubated in natural nests. Hatching success was higher for artificially incubated eggs (hatching success/nest 50–100%, 25 of 28 eggs hatched) compared to eggs from natural nests (hatching success/nest 43–75%, 30 of 50 eggs hatched), though this result was not tested statistically. Hatchlings from artificially incubated nests were heavier than those from natural nests (artificial: 14 g; natural: 9 g), and larger in four of five measures (see paper for details). In September 2004, six natural turtle nests were selected and 40% of eggs were removed for artificial incubation (28 eggs), and the rest left in place (50 eggs). Natural nests were covered with a plastic screen. Removed eggs were placed in cooler boxes (1,000 x 400 x 350 mm) in moist vermiculite (2:1 ratio with water by volume), and additional water was added whenever the vermiculite was dry. Hatchlings were counted, weighed and released at the nesting site two weeks after hatching.

(Summarised by: William Morgan)