Domestic dogs and the Bras´ılia National Park

Animal Conservation. Print ISSN 1367-9430


Domestic dogs as an edge effect in the Bras´ılia National
Park, Brazil: interactions with native mammals

Abstract
Edge effects are a well-known result of habitat fragmentation. However, little has
been published on fragmentation, isolation and the intrusive influence from the
surrounding matrix at the landscape level. The objectives of the present study are
to evaluate the presence of dogs in the Brası´ lia National Park (BNP) in relation to
habitat type and the influence from the surrounding matrix. In addition, this study
examines the response of the native mammal fauna to the presence of dogs. Track
stations were built along dirt roads in the BNP and subsequently examined for the
presence or absence of tracks. We used a stepwise logistic regression to model the
occurrence of five mammal species relative to habitat variables, with an a=0.05 to
determine whether to enter and retain a variable in the model. A simulation of each
species occurrence probability was conducted using a combination of selected
habitat variables in a resource selection probability function. Results indicate a
negative relationship between distance from the BNP edge and the probability of
dog occurrences. From an ecological perspective, the presence of dogs inside the
BNP indicates an edge effect. The occurrence of the maned wolf was positively
associated with distance from a garbage dump site and negatively associated with
the presence of dog tracks. The maned wolf and giant anteater seem to avoid areas
near the garbage dump as well as areas with dog tracks. There is no support for the
possible existence of a feral dog population inside the BNP, but the effects of freeranging
dogs on the wildlife population in such an isolated protected area must not
be neglected. Domestic dog Canis familiaris populations and disease control
programs should be established in the urban, sub-urban and rural areas surrounding
the BNP, along with the complete removal of the garbage dump from the BNP
surroundings.