Hybridization Between a Green Turtle, <em>Chelonia mydas</em>, and Loggerhead Turtle, <em>Caretta caretta</em>, and the First Record of a Green Turtle in Atlantic Canada

Abstract

The Green Turtle (Chelonia mydas) principally occupies tropical and subtropical waters, although juveniles are known to occur seasonally in temperate coastal waters. Collaboration with commercial fishers in eastern Canada yielded the most northerly records of this species in the northwest Atlantic. Here we report on the first confirmed record of a Green Turtle in eastern Canada and on the occurrence of a rare Green Turtle–Loggerhead Turtle (Caretta caretta) hybrid. Hybridization between the Carettini and Chelonini is extraordinary given that these groups have been genetically distinct for 50 million years or more.

Hybridization betweenCrocodylus acutusandCrocodylus moreletiiin the Yucatan Peninsula: I. evidence from mitochondrial DNA and morphology

“…For the most part, detected hybrids were located in coastal areas; therefore, the greatest management concern may be introgression by C. moreletii into the C. acutus populations as stated by Ray et al (2004). The high frequency of C. acutus and C. moreletii hybrids in the sympatric zone on the Yucatan Peninsula (Hekkala, 2004;Ray et al, 2004; this study) suggests that hybridization in the wild is more common than previously expected (Arnold,'97), as also observed in some species of marine turtles (James et al, 2004;Lara-Ruiz et al, 2006).…”

“…Bowen et al,'92;Baker et al,'93;Ball et al,'98) including crocodiles (Glenn et al, 2002). In addition, mitochondrial markers have been useful in the study of interspecific hybridization and introgression as they permit the identification of the maternal parental species in each cross (Karl et al, '95;Barber et al, 2003;Seminoff et al, 2003;Hekkala, 2004;James et al, 2004;Ray et al, 2004;Lara-Ruiz et al, 2006). The purpose of this study is to identify genetically pure individuals of C. acutus and C. moreletii using mtDNA haplotypes and morphology and to demarcate the hybrid zone in the Yucatan Peninsula.…”

Peer Review #1 of "Hawksbill × loggerhead sea turtle hybrids at Bahia, Brazil: where do their offspring go? (v0.1)"

“…x hawksbill turtles (Wood et al, 1983;Conceição et al, 1990;Karl et al, 1995;Seminoff et al, 2003;James et al, 2004;Lara-Ruiz et al, 2006;Reis et al, 2010;Vilaça et al, 2012). Possible sterility and lower fitness of these hybrids is concerning since all sea turtle species are currently threatened (IUCN, 2012); however, the exact causes and consequences of these hybridizations are not yet understood.…”

Hawksbill x loggerhead sea turtle hybrids at Bahia, Brazil: where do their offspring go?

“…In the marine environment hybridization has been described for a range of organisms including corals (Willis et al, 2006), fish (Hubbs, 2013), dolphins (Yazdi, 2002), seals (Kovacs, 1997), whales (Glover et al, 2013) and sea turtles (Karl et al, 1995). Natural hybridization between Cheloniid sea turtle species has been reported for green Chelonia mydas x hawksbill Eretmochelys imbricata, loggerhead Caretta caretta x hawksbill, green x loggerhead, loggerhead x olive ridley Lepidochelys olivacea, and olive ridley x hawksbill turtles (Wood et al, 1983;Conceição et al, 1990;Karl et al, 1995;Seminoff et al, 2003;James et al, 2004;Lara-Ruiz et al, 2006;Reis et al, 2010;Vilaça et al, 2012). Possible sterility and lower fitness of these hybrids is concerning since all sea turtle species are currently threatened (IUCN 2012); however, the exact causes and consequences of these hybridizations are not yet understood.…”