First records of skin lesions in coastal off southern Chile Francisco A. Viddi1, Marie-Françoise Van Bressem2, Maximiliano Bello1, 3 and Ann-Katrien Lescrauwaet4

(1) Centro Ballena Azul, Carlos Anwandter 624, Casa 4, Valdivia, Chile; (2) Peruvian Centre for Cetacean Research (CEPEC), Museo de Delfines, Pucusana, Lima 20, Peru; (3) World Wildlife Fund, Programa Ecorregión Valdiviana, Carlos Anwandter 624, Casa 4, Valdivia, Chile; (4) Vlaams Institutuut voor de Zee vzw, Flanders Marine Institute, Vismijn, Belgium

ABSTRACT MATERIALS AND METHODS

Since the austral summer 2003, the ecology of coastal species, and the The study was developed in two fjords of southern Chile (42o22’S, 72o24’W). potential threats affecting them, are being studied in the Chilean southern fjords, Fieldwork was conducted from December through April during the austral summer where intense aquaculture activities are developed. The main objective of this seasons 2002/2003 and 2003/2004. The dorsal fins and backs of dolphins were study was to detect skin lesions in coastal dolphins in southern Chile. The photographed, using a digital camera Canon EOS 10D and complemented in presence of skin lesions on Chilean ( eutropia), Peale’s some occasions with underwater video footage, to determine the presence of ( australis) and bottlenose dolphins (Tursiops truncatus), and different skin lesions. These were recognized as either irregular, slightly in relief, Burmeister’s ( spinipinnis) were assessed by examining digital grey, black, yellowish or even white skin lesions, some were circular or photographs obtained during 103 marine surveys conducted between January and amorphous patches, some had blister-like appearance. May 2003 and 2004 in two fjords of southern Chile (42o28’S, 72o28’W). Approximately 350 pictures have been examined: 128 images of 13 identified Chilean dolphins, 173 images of 45 identified Peale’s dolphins, 15 images of two Fig. 2: Study area bottlenose dolphins and 34 images of several unidentified Burmeister’s porpoises. Skin lesions have been detected in T. truncatus, L. australis and C. eutropia. Remains of tattoos and tattoo-like lesions were observed on 3 adults C. eutropia, RESULTS caused by a still uncharacterised poxvirus. A calf C. eutropia, tracked from 11 January to 22 February 2003, exhibited several blister-like lesions that grew over Approximately 900 effort-hours during 103 marine surveys have been achieved, time. These invading lesions may be of mycotic origin, possibly a lobo’s disease obtaining more than 5000 digital photographs of dolphins. More than 350 pictures caused by Loboa loboi. The calf had obvious difficulties in breathing and have been examined: 128 images of 13 identified Chilean dolphins, 173 images of swimming, possibly reflecting lung infection and general health decline. A female 45 identified Peale’s dolphins, 15 images of two bottlenose dolphins and 34 presented lesions similar to “ring lesions”, an earlier form of images of several unidentified Burmeister’s porpoises. tattoo disease. Uncategorized lesions have been observed in several Peale’s Skin lesions (or lesion-type) have been detected in T. truncatus, L. australis and C. dolphins. eutropia. Remains of tattoos and tattoo-like lesions were observed on 3 adults C. Although tattoo lesions affect several species of small cetaceans worldwide, no eutropia, caused by a still uncharacterised poxvirus. A calf C. eutropia, tracked skin lesions had ever been reported in Chile. Aquaculture activities in the study from 11 January to 22 February 2003, exhibited several blister-like lesions on both A area generate intense organic enrichment producing important eutrophication and flanks and head that grew over time. These invading lesions may be of mycotic release of antibiotics, which are potential threats to marine . These first origin, possibly a lobo’s disease caused by Loboa loboi. The calf had obvious evidences on skin lesions in dolphins may be related to a degrading environment, difficulties in breathing and swimming, possibly reflecting lung infection and probably associated with aquaculture activities, which should be considered in general health decline. After February 22, its mother was observed alone, future research and management. assuming the death of the ill calf. A female bottlenose dolphin, observed with its calf, presented lesions similar to “ring lesions”, an earlier form of tattoo disease. Finally, Peale’s dolphins presented several type of skin lesions, which have not been classified yet. Within the study area many salmon farms have been set up, with the subsequent increase of boat traffic and pollution, such as chemical and organic B (eutrophication, garbage disposal, etc.).

Fig. 1: Chilean and Peale’s dolphin

INTRODUCTION C DISCUSION The channels, fjords and archipelagos of southern Chile are home for a high diversity of small cetaceans such as endemic Chilean dolphins (Cephalorhynchus Skin lesions have been reported in several species of free-living odontocetes, such eutropia), Peale’s dolphins (Lagenorhynchus australis), Burmeister’s porpoises as bottlenose dolphin Tursiops truncatus, Atlantic white-sided dolphin (Phocoena spinipinnis), bottlenose dolphins (Tursiops truncatus), and orcas Lagenorhynchus acutus, dusky dolphin Lagenorhynchus obscurus, long-beaked (Orcinus orca). This area is being increasingly sought for use by large industries Delphinus capensis, Orcinus orca and Burmeister’s and other human activities, such as aquaculture, fishing, and increased maritime Phocoena spinipinnis. Although skin lesions, mostly related to poxvirus traffic, potentially impacting small cetaceans living close to shore, causing for infections known as “tattoos”, affect species of small cetaceans worldwide, no skin example increasing levels of stress, promoting disease or compromising immunity. lesions had ever been reported in Chile. The invading mycotic disease on the D Skin lesions, such as poxvirus infection or “tattoos”, have been observed in several Chilean dolphin calf is probably the most serious lesion found, which deserve species of free-ranging odontocetes from the North Atlantic, East Pacific and much attention. Aquaculture activities generate intense organic enrichment and Mediterranean Sea, as well as in captive dolphins, but it has never been pollution producing severe environmental stress. This might negatively impact documented for Chilean waters. Here we describe the first insights of skin lesions marine survival, by affecting movement, distribution and Fig. 5: Chilean dolphin calves. A) healthy calf; B) ill calf 11 January; C) ill calf on small cetaceans in Chile, making of this the first steps toward the study on the behavioural patterns, or indirectly by immunodeficiency and promoting disease. 22 February; D) ill calf 20 January epidemiology in coastal dolphins in Chile and its potential impact on their Further work should address estimates on prevalence of skin lesions in relation to populations. species and sex. As it has been observed, some species, such as the Chilean dolphin, seem to have stronger site fidelity and a more restricted coastal habitat, ACKNOWLEDGEMENTS thereby they might likely be more affected by coastal environmental stress than other species. Furthermore, ozone depletion and UV radiation may indeed The Rufford Maurice Laing foundation partially financed this project. represent another health threat for cetaceans in southern Chile. Logistical support has been given by Pumalin Foundation. The authors This work is intended to be a first step toward the identification of any relation would like to thank the comments and suggestions of Rodrigo Hucke-Gaete between pollutants, eutrophication and other environmental stressful variables with and Sonja Heinrich. WWF and CSI have supported FAV with financial aid skin lesions and other diseases on unique dolphin species in Chile. to participate in this conference. Volunteers and friends also deserve our gratitude: Loreto Balkenhol, Sandra Ribeiro, Juan Pablo Torres, Ana de la Torriente and Carolina Zagal.

REFERENCES

Wilson, B., Thompson, P and Hammond, P. 2005. Skin lesions and physical deformities in bottlenose dolphins in the Moray Firth: Population AB Prevalence and age-sex differences. Ambio 26:243-247. Van Bressem, M-F. and Van Waerebeek, K. 1996. Epidemiology of poxvirus in small cetaceans from the Eastern South Pacific. Mar. Mamm. Sci. 12:371-382. Van Bressem, M.-F., Van Waerebeek, K., Reyes, J-C., Dekegel, D. and Pastoret, P-P. 1993. Evidence of poxvirus in dusky dolphin (Lagenorhynchus obscurus) and Burmeister's porpoise (Phocoena spinipinnis) from coastal Peru. J. Wildl. Dis. 29:109-113. Van Bressem, M-F., Van Waerebeek, K. and Raga, J.A. 1999. A review of virus infections of cetaceans and the potential impact of Fig. 4 : Salmon farms in southern Chile morbilliviruses, poxviruses and papillomaviruses on host population dynamics, Dis Aquat Org 38: 53-65. C D Wilson, B., Hammond, P.S. and Thompson, P.M. 1999. Estimating size and assessing trends in a coastal bottlenose dolphin population. Ecol. Applications. 9:288-300. Fig. 3: Skin lesions: tattoo-like lesion on a Chilean dolphin (A), ring-like lesion on bottlenose dolphin (B), uncategorized lesion on Peale’s dolphin (C), remains of tattoos on Chilean dolphins (D).