Managed parks as a refuge for the threatened red squirrel (Sciurus vulgaris) in light of human disturbance

摘要

As the invasive grey squirrel continues to spread, red squirrels are dying out. The result may be isolated populations in managed parks, where access can be controlled. However, recreation can often have a negative effect on wildlife, reducing the conservation potential of parks. Fota Wildlife Park receives over 300,000 visitors each year and is located on an island that is currently free of grey squirrels. We examined the effect of visitors on the existing red squirrel population. Sampling was conducted in the presence and absence of the public. Ten trapping sessions took place from March 2013 to 2014 and faeces were collected to examine stress levels. Squirrels were observed to concentrate their activity in non-public areas and move into public areas when the park was closed. Radio tracked squirrels, from the adjacent gardens (intermediate disturbance), also used habitats in the wildlife park (high disturbance) when it was closed but returned when the park had opened. When squirrels were observed in public areas, visitors were only visible on 15% of occasions. Levels of faecal cortisol metabolites (FCM) were highest in areas where human disturbance was greatest. However, there was no correlation between visitor numbers and the stress levels of squirrels. FCM levels were however, positively correlated with density of squirrels. The fact that high numbers of squirrels continued to utilise the wildlife park demonstrates that managed parks could provide an important reserve for the maintenance of the species, as long as non-public areas are accessible.