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Se presenta información del estado poblacional y distribución geográfica del lobo de río (Pteronura brasiliensis) en la región Madre de Dios durante los años 2014 y 2015. La población registrada fue de 128 individuos para ambos años, agrupados en 22 grupos familiares en el año 2014 y 20 grupos en el año 2015. Los sectores con mayores abundancias fu...
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... We also sampled four unprotected oxbow lakes in the lower part of the Madre de Dios river (12°40 0 S, 69°53 0 W), where significant ASGM activities have been occurring over the last three decades (Caballero-Espejo et al., 2018). Three of these lakes were subject to ASGM and fishing during the research period and one, to which access is restricted, was used for ecotourism and fishing (Mendoza et al., 2017). The lower Madre de Dios ASGM area contains 11 small-sized communities with a formal population of 2500. ...
Human activities increasingly result in disturbance of wild animal populations. Behavioral responses vary according to the type, duration, frequency and intensity of disturbance. Exposure to disturbance, for example, arising from ecotourism, may promote tolerance of humans and drive a decrease in vigilance and avoidance behaviors, whereas disturbance resulting from extractive activities is typically more intense and is likely to be perceived as a threat. To understand how animals cope with land transformation and human presence, it is imperative to study their responses under different disturbance regimes. We performed behavioral sampling of groups of the giant otter, a charismatic top carnivore, exposed to ecotourism, extractive activities (mining and fishing) and control sites without disturbance to compare their responses. Foraging efficiency was impacted by fish abundance and thus was reduced in mined and fished areas. Giant otters in lakes with managed ecotourism did not show avoidance of research vessels and demonstrated reduced rates of defensive behavior compared to control lakes. Groups from lakes with fishing and gold mining showed increased avoidance, suggesting that these types of disturbance may involve more direct conflict. Our findings suggest that noninvasive disturbance such as ecotourism may promote giant otter tolerance to the presence of humans, whereas extractive activities may be perceived as riskier. Current protected area conservation strategies of strict ecotourism regulation and the maintenance of no‐access oxbow lakes may ensure the maintenance of behavioral flexibility in giant otter populations. However, resource depletion and more intense human‐giant otter interactions in disturbed areas may not be sustainable. Further studies are necessary to determine whether distinct disturbance regimes drive longer‐term demographic effects.
Neotropical freshwater habitats are particularly sensitive to degradation by human activity. Piscivorous semi‐aquatic freshwater megafauna inhabit both the terrestrial and aquatic mediums and thus may be good indicators of wetland habitat quality. However, the drivers of their space use at the terrestrial and aquatic landscape levels are not well understood. We studied the spatial behavior and habitat use of giant otters in Madre de Dios, Peru, inhabiting areas with variable levels of protection. We combined unmanned aerial vehicle (UAV) and satellite images to develop different terrestrial and water‐associated land cover variables. We tested the influence of these predictors on giant otter habitat use at multiple spatial scales, comparing used and available locations. Giant otters favored bank areas with dense forest canopy cover. In the aquatic medium, giant otters showed positive selection for open water and fallen logs and avoided floating vegetation. These findings may be explained by preference for optimal fish habitat to maximize foraging yield and bank areas that provide more cover from predators and higher quality denning locations. Variables developed from UAV images outperformed satellite‐derived variables. Despite recent signs of deforestation in lake banks in unprotected areas, spatial model predictions indicated that unprotected oxbow lakes did not differ in their habitat suitability from protected freshwater habitats. Management implications of our findings include identification of factors driving habitat suitability to guide policy and decisions regarding protection or restoration of oxbow lake ecosystems to support giant otter populations. In addition, we demonstrate that UAVs have value in complementing satellite‐derived images and providing a cost‐effective methodology to assess habitat quality for semi‐aquatic species at the land‐water interface.
• Aquatic mammals worldwide are highly threatened in freshwater ecosystems where they are affected by direct human activities (e.g. hunting) as well as indirect human alteration of freshwater ecosystems (e.g. dams, mining activity). Although aquatic mammals of the Amazon Basin are experiencing many growing threats, little is known about the escalating impacts on them, current limitations in protection mechanisms, and possible strategies to ensure their conservation. This study synthesizes the available information on Amazonian aquatic mammals, including the ecological characteristics of these species, key threats, population status and conservation prospects.
• Amazonian aquatic mammals comprise seven species – Inia geoffrensis, Inia boliviensis, Inia araguaiaensis, Sotalia fluviatilis, Trichechus inunguis, Pteronura brasiliensis and Lontra longicaudis – which are characterized by low reproductive rates and keystone ecosystem roles. These species are endangered mainly by biological resource use, natural ecosystem modifications, energy production and mining, and climate change. Although information is sparse, there is evidence that these threats are inducing population declines of Inia spp., and hindering the recovery of populations of P. brasiliensis.
• Protection mechanisms for these species mostly include national and international laws and agreements, legislation governing environmental licensing and protected areas. Each of these protection mechanisms, however, has limited capacity to protect Amazonian aquatic mammals, largely because they are poorly enforced, lack transnational coordination or require population trend data that do not exist.
• Reversing the current state of affairs for Amazonian aquatic mammals requires an integrated research and policy approach that, at a minimum, substantially increases the present capacity to monitor their population responses to human impacts, establishes effective enforcement of existing legislation and prevents further impacts from hydropower development. To implement such an approach, information on the ecology of these species is necessary to create public and scientific awareness.
The giant otter Pteronura brasiliensis , categorized as Endangered on the IUCN Red List, was once widely distributed throughout South America. By the middle of the 20th century the giant otter had become locally extinct along the main rivers of the Orinoco basin. Although some populations seem to have recovered, the paucity of information available does not permit a full evaluation of the species' conservation status. The objective of this study was to estimate the abundance and density of the giant otter population along the Orinoco river in the municipality of Puerto Carreño, Vichada, Colombia, where there is important commercial and recreational fishing. Thirty-nine linear km were surveyed, repeatedly, with a total of 315 km of surveys. Population size was estimated by direct counts of individuals. All individuals detected were photographed and identified individually from their throat pelage patterns. In total, 30 otters were identified, giving a minimum density of 0.77 individuals per km, one of the highest reported for the species in Colombia. Given the high density in this well-developed area, our results highlight the importance of this population for the conservation of the species.
Es un gusto para el comité editorial y comité científico presentar las memorias y libro de resúmenes de nuestro II Congreso Colombiano y III Congreso Latinoamericano de Mastozoología, realizado en la ciudad de Bogotá, Colombia, en las instalaciones de la Universidad Distrital Francisco José de Caldas,
Sede Macarena, entre el 1 y 5 de diciembre de 2015. Este evento representa un avance significativo y un producto natural del crecimiento y desarrollo natural de nuestra disciplina mastozoológica tanto a nivel nacional como Latinoamericano, lo que además muestra el fuerte crecimiento y avance de la ciencia de nuestra región. Con más de 400 ponencias orales y posters, de más de 16 países y cerca de 600 participantes, este Congreso se convierte en el máximo evento de la mastozoología en el país y un muy significativo aporte a la mastozoología Latinoamericana.
La mortalidad de fauna de vertebrados debido a la colisión con vehículos es un impacto humano poco estudiado en áreas de alta biodiversidad. El presente estudio tuvo lugar en las estribaciones nororientales de los Andes ecuatorianos, una región que corresponde a uno de los hotspots más biodiversos a nivel mundial, los Andes Tropicales. Se contabilizaron atropellamientos de fauna silvestre en tres segmentos de carreteras aledañas a tres áreas protegidas: Reserva Ecológica Antisana, Parque Nacional Sumaco Napo Galeras y el Parque Nacional Cayambe Coca. Adicionalmente, se evaluó el efecto del tráfico vehicular y atributos del paisaje en la mortalidad de vertebrados considerando distancias desde los atropellamientos a vegetación remanente, poblados, ríos y quebradas. El área de estudio comprendió 99 km (33 km de cada segmento de carretera), por lo que en 72 días de muestreo se recorrieron 7 128 km, donde se encontraron 452 individuos atropellados (43 anfibios, 88 reptiles, 107 aves y 214 mamíferos). Los vertebrados atropellados correspondieron a 46 especies de fauna silvestre siendo los órdenes con mayor porcentaje de atropellamiento Didelphimorphia (35%), Squamata (19%) y Passeriformes (17%). Los resultados muestran que la distancia a la vegetación remanente es la variable más influyente para la mortalidad de aves, reptiles y mamíferos (exceptuando zarigüeyas), mientras que para anfibios, las variables más importantes son distancia a ríos y distancia a quebradas (intersecciones entre vía y ríos). Además, se evidenció que los atropellamientos fueron más frecuentes en áreas colindantes con zonas de pastoreo. Se sugieren sitios de la zona de estudio donde sería útil implementar medidas de manejo para reducir la mortalidad de fauna por atropellamiento.
