Nesting and conservation of the olive ridley sea turtle (Lepidochelys olivacea) in playa Drake, Osa Peninsula, Costa Rica (2006-2012)

Published source details James R. & Melero D. (2015) Anidación y conservación de la tortuga lora (Lepidochelys olivacea) en playa Drake, península de Osa, Costa Rica (2006 a 2012). Revista de Biología Tropical, 63, 117-129.
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This study is summarised as evidence for the following.

	Action	Category
	Protect nests and nesting sites from predation by camouflaging nests Action Link
	Engage local communities in conservation activities Action Link
	Patrol or monitor nesting beaches Action Link
	Relocate nests/eggs to a hatchery: Sea turtles Action Link

Protect nests and nesting sites from predation by camouflaging nests

A before-and-after, site comparison study in 2005–2012 on a beach in Costa Rica (James & Melero 2015) found that camouflaging olive ridley Lepidochelys olivacea sea turtle nests in situ resulted in similar hatching rates to nests that were moved to an on-beach hatchery with 24-hour monitoring. Results were not statistically tested. Hatching success was similar for nests that were camouflaged (79%) or relocated to the hatchery (79%). The emergence rate of hatchlings from camouflaged nests was 71%, compared to 77% of hatchlings from fenced hatchery nests. Egg poaching reduced from 85% in 2005 to 10% of eggs in 2006–2012. Nesting activity was monitored by nightly beach patrols (4x 4 hours/night) in July/August-December in 2006–2012 (958 nests were laid, 98–177/year). In 2006–2012, nests were either relocated to a monitored on-beach hatchery (363 nests, 38%), or camouflaged (595 nests, 61%; details of camouflaging method not provided) to discourage illegal collecting. Relocated nests were randomly allocated a 1 m² plot in the hatchery and dug into the sand. The hatchery was monitored 24 hours a day during the nesting season. Hatchlings from both treatments were monitored on emergence and nests were excavated after hatching due dates to check hatching success.

(Summarised by: Katie Sainsbury)
Engage local communities in conservation activities

A before-and-after, site comparison study in 2005–2012 on a beach in Costa Rica (James & Melero 2015) found that after involving the local community in monitoring olive ridley turtle Lepidochelys olivacea nests that were relocated to a hatchery and camouflaged, egg poaching decreased. Results were not statistically tested. Egg poaching reduced from 85% in the year before community monitoring began (2005) to 10% of eggs in 2006–2012. In 2006–2012, the local community was involved in monitoring turtle nesting activity and provided 24-hour monitoring to nests that were either relocated to an on-beach hatchery (363 nests, 38%nests) or camouflaged (595 nests, 62%; details of camouflaging method not provided) to discourage illegal collecting. Relocated nests were randomly allocated a 1 m² plot in the hatchery and dug into the sand. Hatchlings from both treatments were monitored on emergence and nests were excavated after hatching due dates to check hatching success.

(Summarised by: Katie Sainsbury)
Patrol or monitor nesting beaches

A before-and-after, site comparison study in 2005–2012 on a beach in Costa Rica (James & Melero 2015) found that relocating olive ridley Lepidochelys olivacea turtle nests to an on-beach hatchery with 24-hour monitoring or camouflaging them on the nesting beach tended to lead to similar hatching rates and lower egg poaching rates. Results were not statistically tested. In total, 79% of nests relocated to the hatchery and of nests camouflaged on the beach successfully hatched. Egg poaching reduced from 85% in 2005 to 10% of eggs in 2005–2012. The emergence rate of hatchlings from hatchery nests was 77%, compared to 71% of hatchlings from camouflaged nests. Nesting activity was monitored by nightly beach patrols (4x 4 hours/night) in July/August–December in 2006–2012 (958 nests were laid, 98–177/year). Nests were either relocated to an on-beach hatchery (363 nests, 38%), or camouflaged (595 nests, 61%) to discourage illegal collecting. Relocated nests were randomly allocated a 1 m² plot in the hatchery and dug into the sand. The hatchery was monitored 24 hours a day during the nesting season. Hatchlings were monitored on emergence and nests were excavated after hatching due dates to check hatching success.

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

A controlled, before-and-after study in 2005–2012 on a beach in Costa Rica (James & Melero 2015) found that relocating olive ridley turtle Lepidochelys olivacea nests to an on-beach hatchery with 24-hour monitoring resulted in similar hatching rates to nests that were left in situ but camouflaged. Results were not statistically tested. The emergence rate of hatchlings from hatchery nests was 77%, compared to 71% of hatchlings from camouflaged in situ nests. The authors reported that egg poaching reduced from 85% in 2005 to 10% of eggs in 2005–2012. Nesting activity was monitored by nightly beach patrols (four 4 h long patrols) in July or August–December in 2006–2012 (98–177 nests laid/year). Nests were either relocated to an on-beach hatchery (363 nests, 40% of total), or camouflaged and left in situ (595 nests, 61% of total) to discourage illegal collecting. Relocated nests were randomly allocated a 1 m² plot in the hatchery and dug into the sand. The hatchery was monitored 24 hours a day during the nesting season. Hatchlings were monitored on emergence and nests were excavated after hatching due dates to check hatching success.

(Summarised by: Katie Sainsbury)