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The first case was observed in September, 1996, of a female with a curved carapace length of 84 cm. This individual turtle had been maintained in captivity by Projeto TAMAR (the national marine turtle conservation program of Brazil) since hatching from a nest laid on the beach in Praia do Forte, Bahia, and had been kept in communal tanks with other species, including green turtles. It is possible that this hawksbill could have been exposed to FP via contact with infected turtles or contaminated water. When 7 to 8 years old, this individual developed a large mass (46cm by 43 cm by 38 cm) on its right front flipper and several small ones (approximately 5 cm in diameter) on its rear flippers and close to its cloaca, and was isolated from other turtles. The masses were pendunculated with a firm and elastic consistency. Normal swimming behavior in this turtle was constrained, therefore the masses were removed surgically. During the surgery, a large internal mass that was smooth and nonpedunculated (i.e. macroscopically different from fibropapillomas) was discovered in the coelemic cavity and had begun to invade the lungs. It was decided not to remove the mass because of its large size and the extent of infiltration into various tissues. The individual died soon afterwards. No histopathology was performed on this internal mass.

The second record also comes from a female turtle, currently with 69 cm curved carapace length, which was raised in captivity by Projeto TAMAR in the state of Sergipe, Brazil, since hatching from its nest. This turtle was also maintained in communal tanks with different species of marine turtles, and may have been exposed to FP from infected turtles or contaminated water. This individual had 3 masses: two on the head and one on the anterior portion of the right front flipper (see front cover). The masses on the head were in the region of the frontal bone, and measured 9cm and 1 cm in diameter. The presence of the larger mass had raised several of the prefontal scutes on the head, exposing a portion of the skull. The third mass was located at the base of the flipper, close to the first marginal scute of the carapace. All external tumors were surgically removed, and currently the animal remains under veterinary care.

Histological analysis of the tumors of both individuals revealed several features that met the criteria of FP previously published (e.g. Santos & Mello 1983): a layer of connective tissue with small mononuclear cells, areas of newly formed and congested vascularization covered with typical keratinized scaly epithelial tissue. There was an absence of displasic or malignant cells, and few instances of fibroblasts depositing collagen in an inflamed area. The margins of the areas treated with surgery were free of the lesion.

There are at least two pertinent factors relative to these cases. The first is that the individuals were raised in captivity from an early age. Captivity may engender FP in this species, for example by compromising their immune systems, by exposing them to pathogens they normally would not encounter, or by placing them in densities that make them more susceptible to infection. In normal wild conditions, these animals may not have developed the tumors. The second factor is that hawksbill turtles in Brazil exhibit a relatively high level of hybridisation with loggerhead turtles (Bass et al. 1996). Although we do not know if these individuals are hybrids, it may be the case that hybrids are more susceptible to FP than non-hybrid hawksbill turtles. Fibropapillomatosis is known to affect green sea turtles in Brazil (Matushima et al. in press). We now confirm that FP has crossed another interspecific barrier, widening the sea turtle populations which may be affected. Further study of FP in hawksbills is needed in the general effort to better understand this disease, which is crucial in developing successful treatments.

Acknowledgements: We thank Jaqueline C. de Castilhos and A. Cesar C.D. da Silva of Projeto TAMAR in Sergipe, and Matthew Godfrey of Projeto TAMAR in Praia do Forte, Bahia. We are grateful for the help and encouragement of George Balazs in preparing this note, and to Ursula Keuper-Bennett for focussing our attention on FP in hawksbills in the first place. Brendan Godley made excellent comments on a previous version of this manuscript. Projeto TAMAR is supported by Petrobras, affiliated with IBAMA, and co-managed by the Fundação Pró-TAMAR.

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