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Volume 15 Issue 1 Pages 1 - 67 (April 1998)

Citation: Soutullo, A., Garbera, R.P. and Gonzalez, E.M. (1998) A Preliminary Survey on the Status of Otters in Uruguay . IUCN Otter Spec. Group Bull. 15(1): 48 - 55

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A Preliminary Survey on the Status of Otters in Uruguay

Alvaro Soutullo1, Ramiro Pereira Garbera1 and Enrique M. Gonzalez2

1VIDA SILVESTRE, Sociedad Uruguaya para la Conservacion de la Naturaleza. Colonia 1884/903, 11200 Montevideo, Uruguay. e-mail: vida-silvestre@geocities.com
2Museo Nacional de Historia Natural. Casilla de Correo 399, 11000, Montevideo, Uruguay

Received 27th April 1998, accepted 3rd July 1998

Abstract: New data on the distribution of the Neotropical river otter (Lontra longicaudis) as well as new records of the giant otter (Pteronura brasiliensis) in Uruguay are provided. The information presented was gathered from otter sighting surveys completed by Uruguayan researchers, wildlife technicians and environmentalists. New localities for both species, comments on the behaviour and data about the habitats used by the Neotropical river otter were obtained. The information about distribution was completed by an examination of records from zoological collections and literature. This survey confirms that the Neotropical river otter is at least fairly common in Uruguay. The conservation status of the giant otter is uncertain. Although considered extirpated for many years, a recent sighting of two individuals has been reported. This information has to be confirmed.

Keywords: otter, Lontra longicaudis, Pteronura brasiliensis, status, Uruguay

INTRODUCTION

The current distribution of the Neotropical river otter (Lontra longicaudis) includes all the Latin American countries from Mexico to Argentina, but excluding Chile. Its conservation status is, however, unknown in some of these countries (Chehébar, 1990; Parera, 1996).

Bocage (1992) reported Neotropical river otters as scarce in Uruguay, with healthy populations only remaining in the area of Bañados de Rocha (eastern part of the country). Chehébar (1990) considered the species widespread throughout the country, with main populations seeming to be in the area of Bañados del Este, Tacuarembo and Esteros de Farrapos.

The former distribution of the giant otter (Pteronura brasiliensis) probably included every country from Panama to Uruguay and northern Argentina (Parera, 1996) except Chile. The current distribution is fragmented, with recorded populations in Ecuador, Colombia, Brazil, Venezuela, Peru, Bolivia, Paraguay, Surinam, French Guyana and Guyana (Chehébar, 1990; Parera, 1996). If they have not been actually extirpated from Argentina and Uruguay, they are probably the most threatened mammals in these countries (Parera, 1996 and pers. obs.).

There are no previous surveys on the distribution and conservation status of Lutrines in Uruguay. The group is represented in national zoological collections by only 18 specimens of L. longicaudis and a single skull of P. brasiliensis collected in 1963.

The main objective of this survey was to establish the current distribution of otters in Uruguay.

MATERIALS AND METHODS

An otters sightings survey was carried out in Uruguay between September 1997 and March 1998. Forms for this survey were distributed by mail to more than 80 Uruguayan researchers, environmentalists and wildlife technicians. For Neotropical river otters the survey was restricted to sightings of otters or their tracks recorded within the last ten years. There was no restriction for records of giant otters.

For L. longicaudis, each form was to be filled with the information of a single sighting (only the most recent observation was recorded if otters or tracks had been observed in that locality on more than one occasion). Each form also requested information about the date of the sighting, the locality, the number of otters observed, how many times otters were observed there and the time of the day when the animals were seen. The following information was also requested for each locality. Considerations about the main threats to their conservation, characteristics of the stream where the observations were made (kind of stream, depth and width), characteristics of the river banks (abundance of plant cover and morphology), and observations on the behaviour of the animals (e.g. vocalisations).

The information about distribution was completed with records from material conserved in the Museo Nacional de Historia Natural de Montevideo (MNHN) and the Facultad de Ciencias zoological collections, and data from literature.

RESULTS

A total of 71 forms were returned. Fifty eight new localities for L. longicaudis and six new records for P. brasiliensis were added to those already known. These results have tripled the number of localities known to be inhabited by otters in Uruguay (see Table 1 and Figure 1).

Map showing position of Uruguay at the lower east side of South America, and map of Uruguay itself showing the courses of the principal rivers, and the location of otter records on them. The greated concentration is along the coast and southern border with Argentina (Rio de la Plata). Click for larger version.
Figure 1. Map of the main rivers and streams of Uruguay indicating places of otter records. (click for larger version)

Comments about behaviour, as well as data about the characteristics of the habitats used by Neotropical river otters were also obtained. In a preliminary analysis of the collected data, no preference for specific habitats was detected. All reported sightings were diurnal. Incidental capture of this species in “nutrias” (Myocastor coypus) traps were reported (J. A. Fernandez, and R. M. Spinola, pers. com.). Three road-kills were recorded.


Table 1: Records of otters from Uruguay

GENUS DEPT LOCALITY YEAR RECORD SOURCE
Pteronura ARTIGAS RIO CUAREIM - RINCON DE PACHECO 1960 Skin SURVEY
Pteronura CERRO LARGO Ayo. SAUCE c/ RIO NEGRO 1963 Skull MNHN 1266
Pteronura ROCHA BAÑADO DE INDIA MUERTA 1930? Skin SURVEY
Pteronura ROCHA UNCERTAIN 1950? Skin SURVEY
Pteronura SALTO Ayo. ITAPEBI - ZONA CASACADA SALTO GRANDE 1977 Otter SURVEY
Pteronura SALTO RIO URUGUAY c/ Ayo. ITAPEBI 1979 Otter SURVEY
Pteronura SALTO RIO ARAPEY GRANDE - O DEL PUENTE ARTIGAS - RUTA 4 1996 Otter SURVEY
Lontra ARTIGAS Ayo. ÑAQUIÑA - TRAMO MEDIO 1997 Otter SURVEY
Lontra ARTIGAS ISLA DEL ZAPALLO - RIO URUGUAY 1996 Track SURVEY
Lontra ARTIGAS PIEDRA PINTADA - RIO CUAREIM - 20 km AGUAS ARRIBA DE ARTIGAS 1997 Otter SURVEY
Lontra ARTIGAS RICARDINHO - RIO CUAREIM - 50 km AGUAS ARRIBA DE ARTIGAS 1997 Otter SURVEY
Lontra ARTIGAS PASO DEL INFIERNO - Ayo. YUCUTUJA GRANDE 1998 Otter SURVEY
Lontra ARTIGAS Ayo. CATALAN GRANDE - CURSO MEDIO 1988 Otter SURVEY
Lontra ARTIGAS Po. MARCELO - Ayo. CATALAN GRANDE c/ Ayo. CATALANCITO 1997 Otter SURVEY
Lontra ARTIGAS PARADA CAMAÑO - Ayo. PELADO ***** Otter SURVEY
Lontra ARTIGAS RICARDINHO - RIO CUAREIM - 50 km AGUAS ARRIBA DE ARTIGAS 1997 Otter SURVEY
Lontra ARTIGAS PARADA CAMAÑO - Ayo. CUARO GRANDE 1998 Otter SURVEY
Lontra ARTIGAS RIO URUGUAY c/ Ayo. MANDIYU 1980 ***** MNHN 3287
Lontra CANELONES PARAJE MOSQUITO  (SOCA) ***** Otter SURVEY
Lontra CANELONES BARRA DE CARRASCO 1996 Otter SURVEY
Lontra CANELONES LAGUNA DEL CISNE 1997 Skin SURVEY
Lontra CANELONES Ayo. PANDO 1997 Otter SURVEY
Lontra CANELONES ATLANTIDA - Bdo. TROPA VIEJA 1958 ***** MNHN 792
Lontra CANELONES RIO STA. LUCIA - AGUAS CORRIENTES 1993 ***** MNHN 3408
Lontra CANELONES PANDO - Ayo. MOSQUITO 1980 ***** MNHN 2963
Lontra CANELONES ATLANTIDA - BAÑADO DEL CISNE 1954 ***** MNHN 287
Lontra CERRO LARGO LAGUNA FORMOSA c/ RIO NEGRO - 15 km N SIERRAS DE ACEGUA 1997 Track SURVEY
Lontra CERRO LARGO Ayo. CHUY 1997 Otter SURVEY
Lontra CERRO LARGO RIO TACUARI c/ LAGO MERIM 1996 Otter SURVEY
Lontra CERRO LARGO PUNTAS Ayo. CORDOBES 1992 Otter SURVEY
Lontra CERRO LARGO ESTANCIA EL TAMARI - Ayo. TACUARI 1997 Otter SURVEY
Lontra CERRO LARGO Ayo. CORDOBES - CERCA DE CERRO CHATO 1988 Otter SURVEY
Lontra CERRO LARGO Cda. BRAVA ***** ***** MNHN 3196
Lontra CERRO LARGO Ayo. CORDOBES 1975 ***** MNHN 2849
Lontra COLONIA Ayo. CUFRE c/ RUTA 1 1998 Track SURVEY
Lontra COLONIA Ayo. SAN PEDRO c/ RIO URUGUAY 1987 Otter SURVEY
Lontra DURAZNO RIO YI c/ Ayo. CABALLERO 1996 Otter SURVEY
Lontra DURAZNO RIO YI - 8 Km AGUAS ABAJO DE DURAZNO 1997 Otter SURVEY
Lontra DURAZNO Ayo. LAS CAÑAS - CAPILLA DE FARRUCO 1996 Otter SURVEY
Lontra DURAZNO EL MEMBRILLAR ***** ***** SURVEY
Lontra DURAZNO Ayo. CHILENO GRANDE c/ CHILENO CHICO 1998 Otter SURVEY
Lontra FLORES RIO YI c/ Ayo. PORONGOS 1997 Otter SURVEY
Lontra FLORIDA RIO STA LUCIA - PASO PACHE 1997 Track SURVEY
Lontra FLORIDA Ayo. ILLESCAS c/ Cda. DE LA VICTORIA 1997 Track SURVEY
Lontra FLORIDA RIO YI c/ Ayo. TIMOTE 1995 Otter SURVEY
Lontra FLORIDA Ayo. ILLESCAS - NE CAPILLA DEL SAUCE 1997 Otter SURVEY
Lontra FLORIDA CHAMIZO PASANDO SAN RAMON 1994 Otter SURVEY
Lontra LAVALLEJA RUTA 8  CERCA DE MARISCALA 1995 Otter SURVEY
Lontra LAVALLEJA AGUAS BLANCAS ***** ***** MNHN 3263
Lontra LAVALLEJA Ayo. PIRANGA - 9ª SECCION 1957 ***** MNHN 288
Lontra LAVALLEJA Ayo. SAUCE - CERCA DE SOLIS DE MATAOJO 1991 Otter Bardier, 1992
Lontra MALDONADO Ayo. PAN DE AZUCAR 1963 ***** MNHN 1935
Lontra MALDONADO CERRO SALAMANCA 1968 ***** MNHN 1328
Lontra MONTEVIDEO LAGUNA PARQUE LECOCQ 1997 Track SURVEY
Lontra MONTEVIDEO LAGUNA PARQUE LECOCQ 1996 Otter SURVEY
Lontra PAYSANDU RIO QUEGUAY ***** Otter SURVEY
Lontra PAYSANDU RIO QUEGUAY GRANDE - 25 km N DE PANDULE - RUTA 90 1995 Otter SURVEY
Lontra RIO NEGRO CERCA DE FRAY BENTOS 1984 ***** MNHN 2966
Lontra RIVERA Ayo. GAJO DEL LUNAREJO 1996 Otter Ibarra et al., 1998
Lontra ROCHA Km 290 RUTA 9 1997 Otter SURVEY
Lontra ROCHA Ayo.  ALFEREZ c/ Ayo. AIGUA 1996 Otter SURVEY
Lontra ROCHA Ayo. BALIZAS - ENTRE LAGUNA Y RUTA 9 1997 Otter SURVEY
Lontra ROCHA CANAL Nº2 c/ CANAL ANDREONI 1997 Otter SURVEY
Lontra ROCHA POTRERILLO 1995 Otter SURVEY
Lontra ROCHA POTRERILLO - LAGUNA NEGRA 1997 Otter SURVEY
Lontra ROCHA Ayo. SAN LUIS - CERCA DE 18 DE JULIO 1997 Otter SURVEY
Lontra ROCHA Ayo. ROCHA - PUERTO DE LOS BOTES 1995 Otter SURVEY
Lontra ROCHA Ayo. BALIZAS c/ OCEANO ATLANTICO 1990 Otter SURVEY
Lontra ROCHA LAGUNA DE CASTILLOS - ESTANCIA BARRA GRANDE 1996 Otter SURVEY
Lontra ROCHA LAGUNA NEGRA 1960 ***** MNHN 979
Lontra ROCHA Ayo. SAN MIGUEL 1989 ***** MNHN 3231
Lontra ROCHA RUTA 9 Km 230 ***** ***** MNHN 3228
Lontra SALTO RIO DAYMAN - TERMAS 1995 Otter SURVEY
Lontra SALTO ALREDEDORES DE LA CIUDAD DE SALTO ***** Otter SURVEY
Lontra SALTO RIO ARAPEY - TODA SU EXTENSION ***** Otter SURVEY
Lontra SALTO RIO URUGUAY ***** Otter SURVEY
Lontra SALTO RIO DAYMAN - TODA SU EXTENSION ***** Otter SURVEY
Lontra SALTO RIO ARAPEY GRANDE - COLONIA RUBIO 1997 Otter SURVEY
Lontra SALTO CERRILLADAS DE Ayo. ARAPEY CHICO 1957 ***** MNHN 285
Lontra SAN JOSE PUERTO ARAZATI ***** ***** ZVCM 1173
Lontra SAN JOSE 4 km NE DE ECILDA PAULLIER ***** Track SURVEY
Lontra SAN JOSE SIERRA DE MAHOMA ***** Otter SURVEY
Lontra SORIANO TAJAMAR A 500 m DEL RIO NEGRO 1989 Otter SURVEY
Lontra SORIANO RIO SAN SALVADOR - CERCA DE DOLORES 1992 Otter SURVEY
Lontra TACUAREMBO RIO NEGRO - LAGO RINCON DEL BONETE - ISLA ARENOSA 1996 Track SURVEY
Lontra TACUAREMBO Ayo. TRES CRUCES - GAJO MEDIO TRAMO SUPERIOR 1991 Otter SURVEY
Lontra TACUAREMBO RIO TACUAREMBO GRANDE ***** ***** MNHN 3277
Lontra TREINTA Y TRES RIO OLIMAR - CIUDAD DE TREINTA Y TRES 1997 Otter SURVEY
Lontra TREINTA Y TRES Ayo. OTAZO 1996 Otter SURVEY
Lontra TREINTA Y TRES CHARQUEADA - PASO EL PELUDO 1997 Otter SURVEY
Lontra TREINTA Y TRES Ayo. LAS PAVAS - 5 km NE DE VALENTINES 1990 Otter SURVEY

DISCUSSION AND CONCLUSIONS

The survey data, the zoological records and the published data strongly suggest that Neotropical river otters occur throughout Uruguay. Within the last ten years Neotropical river otters have been observed at least in 17 of the 19 political divisions (“Departamentos”) of the country. There is no reason to assume that they have been extirpated from those where no recent records have been reported. No conclusions about the areas of the country that support the main populations of this species can be inferred from our survey.

The Neotropical river otter should be considered at least as a fairly common species in Uruguay. Despite this, their populations might be decreasing, and further research should be carried out to discern whether this suspicion has actual fundaments. The results of this research suggest that the former consideration of the species as scarce in the country (Bocage, 1992) was due to the lack of information and not because of actual conservational features.

Although some authors suggest that river otters are nocturnal and crepuscular animals in Uruguay (Gonzalez, 1983; Saralegui, 1996; Ibarra et. al., 1998), all the sightings reported in this survey were diurnal. We conclude from this data that in Uruguay these animals are, at least in part, also active during the day. Whether they are mostly diurnal or crepuscular and nocturnal in Uruguay is not clear yet. Parera (1996) reports this species as diurnal in Argentina, and considers that they become more nocturnal when they are disturbed.

The situation of the giant otter in Uruguay is uncertain. Although Redford and Eisenberg (1992) present four localities for this species in Uruguay, there is only one documented record (Ximenez et al., 1972). This paper presents two localities where they were observed in the late seventies, as well as a sighting of two individuals foraging in 1996. This would be the most southerly record for the species over the last 20 years. As the species is currently thought to be extirpated in Uruguay, and the latest record has to be confirmed, further observations are necessary to confirm the occurrence of the giant otter in Uruguay. Accurate surveys to assess the status of this species should be carried out immediately.

ACKNOWLEDGEMENTS - This survey was supported by VIDA SILVESTRE, Sociedad Uruguaya para la Conservacion de la Naturaleza. We thank the people that provided the information for this paper for their kind co-operation, and the assigned reviewer for their contributions to improve the manuscript.

REFERENCES

Bardier, G. (1992). Uso de recursos y caracteristicas del habitat del “Lobito de rio” Lutra longicaudis (Olfers ,1818) (Mammalia, Carnivora) en el Arroyo Sauce, SE de Uruguay. Boletin de la Sociedad Zoologica del Uruguay, (2ª epoca) 7, 59-60, Montevideo.
Bocage, A. (1992). Mamiferos del Uruguay. Servicio Divulgacion Cientifica, Division Cultura, Intendencia Municipal de Montevideo, 112 p.
Chehébar, C. (1990). Action Plan for Latin American Otters (pp:64-73). In: Foster-Turley, P., Macdonald, S.M., Mason, C.F. (Eds.) Otters: an action plan for their conservation. I-IV+1-126 p. IUCN, Gland.
Gonzalez, J.C. (1983). Los mustelidos del Uruguay. Almanaque del Banco de Seguros del Estado (Montevideo), 66: 227-229.
Ibarra, R., R. Lombardi, R., Wayson, C. (1998). Mamiferos (pp:73-77 and 111-113). In: Berrini, R. (Coord.) Cuenca superior del Arroyo Lunarejo. Ministerio de Vivienda Ordenamiento Territorial y Medio Ambiente/Direccion Nacional de Medio Ambiente & Sociedad Zoologica del Uruguay, 1-10+1-153 p., Montevideo.
Parera, A. (1996). Las “Nutrias Verdaderas” de Argentina (2ª Ed.). Boletín Técnico. Fund. Vida Silvestre Argentina (Buenos Aires). 21: 1-38,.
Redford, K. H., Eisenberg, J.F. (1992). Mammals of the Neotropics. The southern Cone. Vol. 2. Chile, Argentina, Uruguay, Paraguay. The University of Chicago Press, 430 p.
Saralegui, A. (1996). Lobito de Rio Lontra longicaudis (Olfers, 1818). Parques Municipales de Montevideo, Serie Fauna Silvestre del Parque Lecocq. Departamento de Cultura, Intendencia Municipal de Montevideo y Vida Silvestre, Sociedad Uruguaya para la Conservacion de la Naturaleza 3: 1-4.
Ximenez, A., A. Langguth, and R. Praderi. (1972). Lista sistematica de los mamiferos del Uruguay. Anales del Museo de Historia Natural de Montevideo, 7: 1-49.

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