The objective of the study was to determine a prediction equation of body weight of Amazonian manatee calves in captivity using their biometry. It was conducted out with 7 calves (4 males and 3 females) of approximately 8 months of age and average body weight of 29.94 ± 0.055 kg, arranged in pools of sufficient size. Biometry and weighing were performed periodically, with the following measurements: body weight (BW), total curved length (TCL), total length (TL), circumference (CIR), fin width (FW), tail width (TW) and peduncle (PED). Data were subjected to Pearson correlation analysis and linear regression, using the statistical software IBM SPSS 24.0. The results showed a significant correlation (P < 0.05) between BW and TCL, TL, FW, TW, CIR and PED. Six linear simple regression equations were generated with relation to BW, using as predictor variables those that showed positive correlation. The CIR equation independent variable had the highest correlation coefficient and less error estimate (R2 = 0.855, R2aj = 0.852). In addition, three linear multiple regression equations of BW were calculated using the predictor variables previously analyzed by Person correlation analysis. The equation that used all biometric measurements (TCL, TL, FW, TW, CIR and PED) had the highest coefficient of determination and the lowest estimation error to predict BW. In conclusion, the biometric measurements of TCL, TL, FW, TW, CIR and PED showed a high correlation with the BW and can be used as predictive variables of BW of manatee calves, as they are easy to be measured.
Husar, S. (1977) Trichechus inunguis. The American Society of Mammalogists, 72, 1-4.
[3]
Rosas, F.C.W. (1994) Biology, Conservation and Status of the Amazonian Manatee Trichechus inunguis. Mammal Review, 24, 49-59. https://doi.org/10.1111/j.1365-2907.1994.tb00134.x
[4]
Sousa, I.K., et al. (2016) Variaveis hematologicas e bioquimicas de peixeboi da Amazonia (Trichechus inungui) jovens. Pesquisa Veterinaria Brasileira, 36, 869-873. https://doi.org/10.1590/s0100-736x2016000900013
[5]
Domning, D. (1981) Manatees of the Amazon. Sea Frontiers, 18-23.
[6]
Timm, R., Albuja, L. and Clauson, B. (1986) Ecology, Distribution, Harvest, and Conservation of the Amazonian Manatee Trichechus inunguis in Ecuador. Biotropica, 18, 150-156. https://doi.org/10.2307/2388757
[7]
Rosas, F.C.W. (1991) Peixeboi da Amazonia Trichechus inunguis (Natterer, 1883). In: Capozzo, H.L. and JunRn, M., Eds., Estado de Conservacion de los Mamiferos Marinos del Atlantico Sudoccidental, United Nations Environment Programme, Nairobi, Informes y Estudios del Programa de Mares Regionales del PNUMA, 138, 178-181.
[8]
Reeves, R.R., Leatherwood, S., Jefferson, T.A., Barbara, E. and Henningsen, T. (2007) Amazonian Manatees, Trichechus inunguis, in Peru: Distribution, Exploitation, and Conservation Status. Interciencia, 21, 246-254.
[9]
Soini, P. (1992) Evaluación preliminar de la vaca marina (Trichechus inunguis). RN Pacaya-Samiria: Estacionbiologica 1979-1994, 35, 369-372.
[10]
IUCN (2016) IUCN Red List of Threatened Animals. IUCN, Gland, Switzerland and Cambridge, UK.
[11]
Soini, P., Sicchar, L., Gil, G., Fachìn, A., Pezo, R. and Chumbe, M. (1996) Una evaluación de la faunasilvestre y su aprovechamiento de la Reserva Nacional Pacaya Samiria, Perú. DocumentoTécnico No 24. IIAP, Iquitos, 64.
[12]
Silva, J. and Montes, D. (2014) Conocimientos, conservación y avistamiento del manatí amazónico (Trichechus inunguis), según los pobladores de la cuenca del río Ucayali (Loreto, Perú), 32-38.
[13]
MINAM (2014) Especies de Fauna Silvestre Peruana en los apendices de la CITES, (CoP 16), 65.
[14]
Resolución Ministerial No 147-2001-PE (2001) Aprueban el Reglamento de Ordenamiento Pesquero de la Amazonía Peruana, 5.
[15]
Decreto Supremo No 034-2004-AG (2007) Aprueban categorización de especies amenazadas de fauna silvestre y prohíben su caza, captura, tenencia, transporte o exportación con fines comerciales, 4.
[16]
Hacon, S., et al. (2008) An Overview of Mercury Contamination Research in the Amazon Basin with an Emphasis on Brazil. Cadernos de Saúde Pública, 24, 1479-1492. https://doi.org/10.1590/S0102-311X2008000700003
[17]
Soto, A. (2007) Caza del manatí amazónico en la Reserva Nacional Pacaya Samiria. Perú. Centro de Datos para la Conservación, Universidad Nacional Agraria La Molina, 23.
[18]
Rudolf, V.H.W. (2012) Seasonal Shifts in Predator Body Size Diversity and Trophic Interactions in Size-Structured Predator-Prey Systems. Journal of Animal Ecology, 81, 524-532. https://doi.org/10.1111/j.1365-2656.2011.01935.x
[19]
Castelblanco-Martínez, D.N., Morales-Vela, B. and Padilla-Saldívar, J.A. (2014) Using Craniometrical Predictors to Infer Body Size of Antillean manatees. Mammalia, 78, 109-115. https://doi.org/10.1515/mammalia-2012-0136
[20]
Santos, E.P. (1978) Dinamica de Populacoes aplicada à pesca e piscicultura. Editora da Universidade de Sao Paulo, Sao Paulo, 129.
[21]
De Mello, F.T., Vidal, N., Gonzalez-Bergonzoni, I. and Iglesias, C. (2009) Length-Weight Relationships of Eight Fish Species from the Lower Section of the Uruguay River (Río Negro, Uruguay). Journal of Applied Ichthyology, 25, 128-129. https://doi.org/10.1111/j.1439-0426.2008.01155.x
[22]
Pinheiro, M.A.A. and Fiscarelli, A.G. (2009) Length-Weight Relationship and Condition Factor of the Mangrove Crab Ucides cordatus (Linnaeus, 1763) (Crustacea, Brachyura, Ucididae). Brazilian Archives of Biology and Technology, 52, 397-406. https://doi.org/10.1590/S1516-89132009000200017
[23]
Castellini, M.A. and Calkins, D.G. (1993) Mass Estimates Using Body Morphology in Steller Sea Lions. Marine Mammal Science, 9, 48-54. https://doi.org/10.1111/j.1748-7692.1993.tb00425.x
[24]
Ireland, D., Garrott, R.A., Rotella, J. and Banfield, J. (2006) Development and Application of a Mass-Estimation Method for Weddell Seals. Marine Mammal Science, 22, 361-378. https://doi.org/10.1111/j.1748-7692.2006.00039.x
[25]
de Bruyn, P.J.N., Bester, M.N., Carlini, A.R. and Oosthuizen, W.C. (2009) How to Weigh an Elephant Seal with One Finger: A Simple Three Dimensional Photogrammetric Application. Aquatic Biology, 5, 31-39. https://doi.org/10.3354/ab00135
[26]
Rosas, F.C.W., da Silva, V.M.F., Sousa-Lima, R.S., d’Affonseca Neto, J.A. and Mattos, G.E. (2001) Adoption and Growth of a Captive Amazonian Manatee (Trichechus inunguis) Calf. Abstract Book of the 14th Biennial Conference on the Biology of Marine Mammals, Vancouver, 28 November-3 December 2001, Society of Marine Mammalogy, Vancouver, 183.
[27]
Amaral, R.S., Da Silva, V.M.F. and Rosas, F.C.W. (2010) Body Weight/Length Relationship and Mass Estimation Using Morphometric Measurements in Amazonian Manatees Trichechus inunguis (Mammalia: Sirenia). Marine Biodiversity Records, 3, 1-4.
[28]
Colares, F.A.P. (2002) Estudo de modelos nao lineares de crescimento em peixeboi marinho Trichechus manatus manatus e peixeboi amazanico Trichechus inunguis (Mammalia: Sirenia) em cativeiro. Tese de Doutorado, Universidade Federal de Minas Gerais, Belo Horizonte.
[29]
Albuquerque Jr., D.P. (2003) Descricao histológica do tecido ósseo do domo timpanico, estimativa de idade e crescimento em cativeiro do peixeboi da Amazonia Trichechus inunguis (Natterer 1883) Mammalia, Sirenia. Dissertacao de Mestrado, Universidade Federal do Amazonas, Manaus.
[30]
Vergara-Parente, J., Parente, C., Marmontel, M., Carlos Ramos Silva, J. and Bezerra Sa, F. (2010) Growth Curve of Free-Ranging Trichechus inunguis. Biota Neotropica, 10, 8-11. https://doi.org/10.1590/s1676-06032010000300009
[31]
Santos, E.P. (1978) Dinamica de populacoes aplicadaàpesca e piscicultura. Editora da Universidade de Sao Paulo, Sao Paulo, 129 p.
[32]
Odell, D.K., Forrester, D.J. and Asper, E.D. (1978) A Preliminary Analysis of Organs Weights and Sexual Maturity in the West Indian Manatee (Trichechus manatus). Proceedings of the 1st Workshop on the West Indian Manatee in Florida, Orlando, 27-29 March 1978, Florida Department of Natural Resources, Orlando, 52-65.
[33]
Trites, A.W. and Pauly, D. (1998) Estimating Mean Body Masses of Marine Mammals from Maximum Body Lengths. Canadian Journal of Zoology, 76, 886-896. https://doi.org/10.1139/z97-252
[34]
Rosas, F.C.W., Rocha, C.S., Mattos, G.E. and Lazzarini, S.M. (2009) Bodyweight-Length Relationships in Giant Otters (Pteronura brasiliensis) (Carnivora, Mustelidae). Brazilian Archives of Biology and Technology, 52, 587-591. https://doi.org/10.1590/S1516-89132009000300010
[35]
Adulyanukosol, K., Prasittipornkul, C., Man-Anansap, S. and Boukaew, P. (2007) Stranding Records of Dugong (Dugong dugon) in Thailand. Proceedings of the 4th International Symposium on SEASTAR 2000 and Asian Bio-Logging Science, Phuket, 15-17 December 2007, Kyoto University, Phuket, 51-57.
[36]
Waite, J.N. and Mellish, J.A.E. (2009) Inter- and Intra-Researcher Variation in Measurement of Morphometrics on Steller Sea Lions (Eumetopias jubatus). Polar Biology, 32, 1221-1225. https://doi.org/10.1007/s00300-009-0649-7
