Reintroduction of Kemp’s Ridley (Lepidochelys kempii) sea turtle to Padre Island national seashore, Texas and its connection to head-starting

Published source details Shaver D.J. & Caillouet Jr C.W. (2015) Reintroduction of Kemp’s Ridley (Lepidochelys kempii) sea turtle to Padre Island national seashore, Texas and its connection to head-starting. Herpetological Conservation and Biology, 10, 378-435.
Share Tweet Email

Actions

This study is summarised as evidence for the following.

	Action	Category
	Head-start wild-caught reptiles for release: Sea turtles Action Link
	Relocate nests/eggs for artificial incubation: Sea turtles Action Link

Head-start wild-caught reptiles for release: Sea turtles

A replicated, before-and-after study in 1978–2014 on sandy beaches in Texas, USA (Shaver & Caillouet 2015) found that some released female head-started kemp’s ridley turtles Lepidochelys kempii, that were ‘imprinted’ by allowing them to crawl to the sea before bringing them in to captivity, returned to nest on or near to the beach that they had been imprinted on at least once. In 37 years, 125 of 916 (14%) nests were laid by 53 different head-started female Kemp’s ridley turtles on the beaches where they were imprinted (turtle ages: 10–26 years old, from 12 release cohorts). The first head-started kemp’s ridley turtle nests were documented 10–12 years after the nesting females were released and 19 years after the head-start programme began. Over the 37-year programme, 9,204 hatchlings laid by imprinted head-started turtles were released and Kemp’s ridley turtle nest numbers laid on the Texas coastline increased to 119 nests in 2014, from near zero in 1979 (nest numbers fluctuated, see original paper for details). In 1978–2000, approximately 22,507 Kemp’s ridley turtle eggs were artificially incubated (1,000–2,000 eggs/year). After emergence, hatchlings were released on one of two beaches and allowed to crawl to the sea (‘imprinted’), and collected again for head-starting. In 1979–2001, imprinted, individually-marked, head-started turtles were released after 7–33 months in captivity (~23,853 imprinted head-starters released in multiple locations). Head-started nesting females were surveyed in 1986–2014 by beach patrols and satellite tracking. Eggs from all known turtle nests in the USA were collected for artificial incubation until 2014 (1,667 total nests; nesting turtles examined in 916 nests).

(Summarised by: Katie Sainsbury)
Relocate nests/eggs for artificial incubation: Sea turtles

A controlled study in 1979–2014 on sandy beaches in the Gulf of Mexico, Texas, USA (Shaver & Caillouet 2015) found that artificially incubated kemp’s ridley turtle Lepidochelys kempii nests had higher hatching success than nests left in situ. Results were not statistically tested. Emergence success of artificially incubated kemp’s ridley turtle nests was 82% and hatching success of in situ nests was 62%. The authors reported that many in situ nest hatchlings did not make it to the sea successfully. Over the 37-year programme, 130,847 artificially incubated hatchlings emerged successfully and were released. In 1979–2014, the majority of kemp’s ridley turtle nests laid in the USA were collected for artificial incubation (1,606 nests) and a small number hatched in situ (61 nests). Hatching rates were assessed for 26 in situ nests laid in 1979–2008.

(Summarised by: Katie Sainsbury)