Fritts, Thomas H. and M. Angela McGehee 



Effects of Petroleum on the Development 

 and Survival of Marine Turtle Embryos 



Museum of Southwestern Biology 



University of New Mexico 



Albuquerque, NM 87131 USA 



Department of Marine Sciences 



University of Puerto Rico, RUM 



May ague z, PR 00709 USA 



The vulnerability of marine turtle progeny in the event of a 

 petroleum spill in waters adjacent to a nesting beach was 

 investigated at the nesting beach of Kemp's ridley sea turtle 

 ( Lepidochely s kempi ) near Rancho Nuevo in Tamaulipas, Mexico. 

 Petroleum from the IXTOC oil well washed up on this beach after 

 the nesting season was completed in 1979. Oil was still evident 

 on the beach in the form of tar during the nesting season in 

 1980. Nine clutches of eggs were collected from nesting ridley 

 turtles in 1980 for comparative incubation experiments. Half of 

 each clutch was incubated in contaminated sand taken from areas 

 of the beach where turtles usually nest and half in clean sand 

 collected from the dune areas of the beach. The results 

 indicated no significant differences in hatching success, 

 incubation time or hatchling morphology between the two groups. 

 The quantity and weathered state of oil remaining on the beach 

 one year after the IXTOC spill did not appear to affect 

 incubating sea turtle embryos. 



Laboratory experiments were conducted with five clutches of 

 eggs collected from nesting loggerhead sea turtles ( Caretta 

 caretta) on Merritt Island, Florida in 1980. Ninety eggs were 

 selected randomly from each clutch, divided into six subsamples 

 of 15 eggs each and incubated in buckets containing 4 kg of sand. 

 Subsamples were subjected to the following treatments: 



A. Control — no oil added 



B. Light dosage — 7.5 ml of crude oil (0.5 ml per egg) 

 mixed with the sand at the initiation of incubation 



C. Medium dosage — 15.0 ml of crude oil (1.0 ml per egg) 

 mixed with the sand at the initiation of incubation 



D. Heavy dosage — 30.0 ml of crude oil (2.0 ml per egg) 

 mixed with the sand at the initiation of incubation 



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