Patterns and intensity of ghost crab predation on the nests of an important endangered loggerhead turtle population

Published source details Marco A., da Graça J., García-Cerdá R., Abella E. & Freitas R. (2015) Patterns and intensity of ghost crab predation on the nests of an important endangered loggerhead turtle population. Journal of Experimental Marine Biology and Ecology, 468, 74-82.
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This study is summarised as evidence for the following.

	Action	Category
	Relocate nests/eggs to a nearby natural setting (not including hatcheries): Sea turtles Action Link
	Protect nests and nesting sites from predation using artificial nest covers: Sea turtles Action Link
	Relocate nests/eggs to a hatchery: Sea turtles Action Link

Relocate nests/eggs to a nearby natural setting (not including hatcheries): Sea turtles

A controlled study in 2008 on a sandy beach in Boa Viste, Cape Verde (Marco et al. 2015) found that loggerhead turtle Caretta caretta nests relocated away from the shoreline experienced a similar amount of predation by ghost crabs Ocypode cursor and had similar hatching success compared to natural nests left in situ. Ghost crab predation rates were similar in nests that were relocated away from the shoreline (41%) and nests that were left in place (55%). Hatching success was also similar in nests that were relocated away from the shoreline (42% success) and nests that were left in place (33% success). Turtle nests were excavated, eggs counted and reburied in another part of the beach (20 nests) or left in the same place without any protection (20 nests). Nests were monitored daily until emergence and hatchling tracks were counted. All nests were excavated after last emergence and remaining eggs counted for analysis.

(Summarised by: Katie Sainsbury)
Protect nests and nesting sites from predation using artificial nest covers: Sea turtles

A controlled study in 2008 on a sandy beach in Boa Viste, Cape Verde (Marco et al. 2015) found that loggerhead turtle Caretta caretta nests reburied in mesh cages or under netting had higher hatching success and lower rates of ghost crab Ocypode cursor predation compared to unprotected nests. Hatching rates were higher in nests that were protected with mesh (cage: 82%; netting: 60% success) compared to nests that were not protected (33% success). Ghost crab predation rates were lowest in nests that were buried in mesh cages (4%), compared to under mesh netting (22%) or unprotected nests (55%). Turtle nests were excavated, eggs counted and reburied in the same place either inside a mesh cage (20 nests), underneath a horizontal 1m² plastic mesh buried 10 cm under the surface (20 nests) or without any protection (20 nests). Nests were monitored daily until emergence. Hatchlings were counted and released from nests with protection. Hatchling tracks were counted from nests with no protection. All nests were excavated after last emergence and remaining eggs counted for analysis.

(Summarised by: Katie Sainsbury)
Relocate nests/eggs to a hatchery: Sea turtles

A controlled study in 2008 on a sandy beach in Boa Viste, Cape Verde (Marco et al. 2015) found that loggerhead turtle Caretta caretta nests relocated to beach hatcheries without ghost crabs Ocypode cursor had higher hatching success and lower predation rates compared to nests left in situ. Hatching success was higher in nests that were relocated to hatcheries (65% success) compared to nests that were left in situ (33% success). Ghost crab predation rates were lower in nests that were relocated to hatcheries (2%) compared to those that were left in situ (55%). Turtle nests were excavated to count the eggs and reburied in either a hatchery (20 nests) or in the same place without any protection (20 nests). Nests were monitored daily until emergence. Hatchlings were counted and released from hatchery on emergence. Hatchling tracks were counted from other nests. All nests were excavated after last emergence and remaining eggs counted for analysis.

(Summarised by: Katie Sainsbury)