How do hatcheries influence embryonic development of sea turtle eggs? Experimental analysis and isolation of microorganisms in leatherback turtle eggs

Abstract

Many conservation programs consider translocation of turtle nests to hatcheries as a useful technique. The repeated use of the same incubation substrate over several seasons in these hatcheries could, however, be harmful to embryos if pathogens were able to accumulate or if the physical and chemical characteristics of the incubation environment were altered. However, this hypothesis has yet to be tested. We conducted two field experiments to evaluate the effects of hatchery sand and eggshell decay on the embryonic development of leatherback sea turtle eggs in Colombia. We identified the presence of both fungi and bacteria species on leatherback turtle eggs. Sea turtle eggs exposed to previously used hatchery substrates or to decaying eggshells during the first and middle third of the embryonic development produced hatchlings that were smaller and/or weighed less than control eggs. However, this did not negatively influence hatching success. The final third of embryonic development seems to be less susceptible to infection by microorganisms associated with decaying shells. We discuss the mechanisms that could be affecting sea turtle egg development when in contact with fungi. Further studies should seek to understand the infection process and the stages of development in which the fungi are more virulent to the eggs of this critically endangered species.

Mycobiota from the eggs, nests and stillbirths of Eretmochelys imbricata Linneus 1766 (Testudines: Cheloniidae) in Pernambuco State, Brazil

“…These microorganisms are usually saprobes but can invade living tissue under favorable conditions, and studies have reported that some of these fungi species infects sea turtle eggs and cause embryo mortality. Patino-Martinez et al (2012) reported similar results in the eggs of the sea turtle Dermochelys coreacea in Colombia, where F. solani and F. oxysporum were identified by phylogenetic analyzes; these fungi were possibly affecting the phenotype of the hatchling (body size). The first way of contamination of the eggs by Fusarium species probably occur through the secretion present in the oviduct, as suggested by Phillot et al (2002), likewise it might be the reason for fungi contamination in nests of other species that belong to Cheloniidae family, since several species of fungi have been isolated from the cloaca of females during breeding.…”

Potential limitations of behavioral plasticity and the role of egg relocation in climate change mitigation for a thermally sensitive endangered species

“…Relocation of sea turtle eggs as a management strategy used to increase hatchling production and enhance population recovery is ubiquitous worldwide (Chacón‐Chaverri & Eckert, ; Formia, Tiwari, Fretey, & Billes, ; García, Ceballos, & Adaya, ; Naro‐Maciel, Mrosovsky, & Marcovaldi, ; Patino‐Martinez, Marco, Quinones, & Hawkes, ). By utilizing internationally recognized best practices throughout the egg relocation process (Eckert et al, ), many of the concerns about possible undesired biological outcomes (Mrosovsky, ; Pilcher & Enderby, ; Prichard, ) can be avoided or mitigated (Kornaraki, Matossian, Mazaris, Matsinos, & Margaritoulis, ; Marcovaldi & Marcovaldi, ; Patino‐Martinez, Marco, Quinones, Abella, et al, ). Because temperatures are predicted to increase substantively in Central America over a relatively short period, the influence of sea turtle egg relocation on the thermal regimes of nest environments, primary sex ratios, and hatchling fitness compared with in situ clutches is a top research priority, particularly for severely depleted populations of highly endangered species.…”

Predaceous Fire Ants (Hymenoptera: Formicidae) at Sea Turtle (Testudines: Cheloniidae) Nesting Beaches and Hatcheries in El Salvador

“…Given the ubiquitous use of hatcheries for incubating sea turtle eggs worldwide (e.g., Mortimer et al 1993;Marcovaldi & Marcovaldi 1999;García et al 2003;Chacón-Chaverri & Eckert 2007;Patino-Martinez et al 2012), we believe it is important for hatchery managers to recognize the potential threat that predaceous ants pose to hatchling sea turtles. Hatchery managers may be unknowingly releasing apparently healthy but stung hatchlings to the ocean, only to have the hatchlings soon die from sting-related impairment.…”

“…In the case of sea turtles, conservationists commonly relocate complete clutches of sea turtle eggs from high-risk nesting beaches where eggs are vulnerable to human poaching, depredation by animals, and loss by tidal inundation (e.g., Mortimer et al 1993;Marcovaldi & Marcovaldi 1999;García et al 2003;Chacón-Chaverri & Eckert 2007;Patino-Martinez et al 2012). These eggs are then usually incubated at protected hatcheries to increase survival rates of eggs and hatchlings.…”