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Medrano, F.

Publications and source records attributed to Medrano, F..

2 recordsLinked to original sources

Characterizing dog communities adjacents to key shorebird sites in Chile

Free-ranging domestic dogs can cause numerous negative impacts on public health, tourism, and the environment. Some of these impacts on wildlife are compounded and facilitated by human communities, for example through the provision of food, health care, and shelter, which altogether increase the dogs life expectancy. Shorebirds are one of the groups adversely affected by dogs through nest predation, behavioral changes, and persecution during foraging and roosting periods. In Chile, dogs are a ubicutous threat in wetlands. In this study, we characterized the dog populations at the mouth of the Lluta River (Chacalluta area) and the Coihuin wetland (Coihuin-Chamiza area), both of international importance for shorebirds. We estimated the total abundance of dogs, their seasonal survival, and demographic and behavioral traits by photographic capture-recapture methods in eight surveys of 6.6 km2 for Chacalluta and 2.0 km2 for Coihuin-Chamiza. We estimated a population size of 167 individuals in Chacalluta and 505 individuals in Coihuin-Chamiza, a relatively low survival rate in both sites, a healthy body status in more than 80% of the dogs, small group sizes (1-2 individuals), and movements of 1,000 to 3,000 meters between locations. We report patterns associated with human ownership, indicating irresponsible pet ownership. This information will be the basis for developing public policies and evaluating strategies to lessen their impact on shorebirds, such as demographic control of the animal population, reduction of abandonment, and promotion of responsible pet ownership practices.

zoology↗

Dogs density drives the reproductive effort of American Oystercatchers (Haematopus palliatus) in disturbed habitats of the Maule Region, central Chile

The American Oystercatcher (Haematopus palliatus) is a shorebird specialized in coastal environments across the Americas. Thus, anthropic extensive use of the shoreline including the introduction of dogs and vehicles to beaches could directly impact fitness, and ultimately the persistence of the species populations. In this study, we aimed to assess the impact of pedestrians, vehicles and dogs on the nest density, productivity and hatching success of the American Oystercatcher in the Maule Region, central Chile. To this end, we sampled sandy beaches, quantifying the number of nests, eggs, chicks, but also pedestrians, vehicles and dogs during the breeding seasons of 2023 and 2024. We assessed for the influence of these threats on parameters of reproductive output by using Generalized Linear Mixed Models. We found that the number of dogs is the only variable that negatively impacts the number of nests, eggs and chicks of the American Oystercatcher in the sampled areas. Reducing the impact of dogs is a ubiquitous challenge in coastal environments of central Chile, however current regulations do not allow management relying on removal of dogs from important areas for biodiversity.

ecology↗