Roaming characteristics and feeding practices of village dogs scavenging sea‐turtle nests

Abstract

Village dogs are reported to prey on sea-turtle nests at various beaches worldwide. Sea-turtle species present in Mexico include six species, which are listed under the International Union for Conservation of Nature Red List. It is however not clear why dogs scavenge and how they enter nesting areas; this hinders effective management of dogs at sea-turtle nesting beaches. Hunger, for example, could be a driving factor for village dogs to scavenge sea-turtle nests. The aim of this study was to gain insight into roaming characteristics and feeding practices of dogs scavenging sea-turtle nests. Movements of 19 village dogs (9 nest scavengers and 10 non-nest scavengers) at Colola village and beach (an important nesting ground for the eastern Pacific green turtle: Chelonia mydas) were monitored through radio-tracking and direct observations. A prerequisite for nest scavenging is traveling to the beach. We computed 'distance from home to beach' and 'the activity range' of nest scavengers and non-nest scavengers. Furthermore, the dogs' owners were interviewed regarding feeding practices. Nest scavengers had a lower metabolic energy intake of their daily food corn tortillas (296 kJ kg −1 BW 0.75 ) than non-nest scavengers (464 kJ kg −1 BW 0.75 ) (two-sample t-test = 2.67, P = 0.017). Moreover, 39% of owners reported that they provided turtle eggs or egg shells to their dogs at least once. The activity range of nest scavengers was significantly larger than that of non-nest scavengers (F = 11.64, P = 0.007). Dogs were generally found at the beach at night (42%) and dawn (34%). Our findings have implications for the management of dogs at sea-turtle nesting beaches. We recommend that dogs' movements should be restricted between night (09:00 pm) and dawn (06:00 am) and that sufficient and adequate feeding of dogs should be promoted among dog owners.

Fine-scale movements of rural free-ranging dogs in conservation areas in the temperate rainforest of the coastal range of southern Chile

“…expected and as previously reported(Ruiz Izaguirre et al, 2014;Woodroffe and Donnelly, 2011), dogs spend most of their time close to their homestead. Second, when forays occur, movement is directional and follows primarily human-dominated landscapes with occasional excursions into protected habitats, particularly where roads facilitate movement into forested areas.…”

“…Recent telemetry studies in dogs show a clear selection for anthropogenic-dominated landscapes in rural areas (Ruiz Izaguirre et al, 2014;Vanak and Gompper, 2010;Woodroffe and Donnelly, 2011). In particular, it is clear that dogs mostly stay close to their house of origin.…”

Roaming behaviour of dogs in four remote Aboriginal communities in the Northern Territory, Australia: preliminary investigations

“…Meek used radio‐tracking to investigate the roaming behaviours and HRs of 10 dogs in coastal NSW, a method requiring researchers to locate dogs using a radio antenna and then track them on foot, recording their locations. Similarly, Ruiz‐Izaguire et al used radio‐tracking to determine the roaming characteristics of dogs in an island village off the coast of Mexico, reporting difficulties tracking dogs at night because of local perceptions . In India, mark and re‐sight methods, as well as direct observation, have been used to determine the HRs of free‐roaming dogs and to monitor the effects of animal birth control programs on dog demographics.…”

“…Similarly, Ruiz-Izaguire et al used radio-tracking to determine the roaming characteristics of dogs in an island village off the coast of Mexico, reporting difficulties tracking dogs at night because of local perceptions. 12 In India, mark and resight methods, 13,14 as well as direct observation, 15 have been used to determine the HRs of free-roaming dogs and to monitor the effects of animal birth control programs on dog demographics. These methods allow data collection to occur only at specified time periods during the day and involve many hours of observations, which is not always practical.…”

Pressão de propágulos ou distúrbios? Decifrando os determinantes da invasão por cachorros na Mata Atlântica

“…Portanto, a atividade e movimentação dos cachorros devem aumentar e, como consequência, a detecção em pontos amostrais incluídos nas áreas de vida dos cachorros, ou seja, em pontos ocupados, é também maior nessas épocas. Alguns trabalhos de fato sugerem que a atividade de cachorros é menor em temperaturas elevadas (Berman & Dunbar, 1983;Ruiz-Izaguirre et al, 2015). Assim, trabalhos futuros sobre cachorros envolvendo a detecção dos indivíduos por armadilhas fotográficas, ou relacionados ao uso do habitat e padrões de movimentação e atividade, independente da metodologia utilizada (e.g.…”