The Effects of Increasing Visitor and Noise Levels on Birds Within a Free-flight Aviary Examined Through Enclosure Use and Behavior

Abstract

Visitors in a zoo environment have the potential to impact the animals that they are viewing in a variety of ways. Recently, there have been suggestions that free-range enclosures, where visitors can walk directly through an animal's exhibit, may reduce the potential for negative visitor impacts. The aim of this study was to examine associations between visitor numbers and noise levels and enclosure use and the stress and critical behavior of 24 bird species housed in a free-flight, mixed species aviary. Using GIS (Geographic Information Systems), the locations of the birds were marked on a digital map of the aviary, with their behavior and vertical distance above the ground also marked. In addition, visitor numbers and noise levels were simultaneously monitored using scan sampling. Thirty-minute intervals were used to collect bird data, while 10-minute intervals were used to collect the visitor data. Under periods of high visitor numbers, several changes in how the birds used their enclosure space were observed, including; movement away from the visitor pathway, decreased range sizes and increased use of vegetation cover. However, the lack of association between visitor numbers and the performance of stress related (pacing, aggression), and critical behavior (feeding, resting, nesting), suggest that the birds were not experiencing substantial negative welfare consequences. Instead, the ways in which the birds used the space in their free-range enclosure appears to have minimized any potential negative effects during high visitor periods.

Bold Frogs or Shy Toads? How Did the COVID-19 Closure of Zoological Organisations Affect Amphibian Activity?

“…The reduction in these resources and the enclosure suitability increases the chance of aggression, reduction in basic biological processes, increased competition, and a reduction in overall welfare standards [8]. The evaluation of enclosure suitability should consider where visitor effect may come from and their potential influence on the inhabitants, and not just the physical measurements of the enclosure; such considerations may improve welfare standards for amphibians [43].…”

“…Other taxa have benefited from research into the type of stress caused by a response to visitor presence [43,51]. Visitors causing vibration, auditory levels, the physical presence of potential danger, a change in light levels, or sudden movements can cause stressors in animals; further research in these areas would help to determine the types of mitigation that can reduce stress and increase visibility.…”

Effects of Crowd Size, Composition, and Noise Level On Pool Use in a Mixed-Species Penguin Colony

“…In addition to potential differences in guest behavior between studies, the indoor penguin habitat at the Saint Louis Zoo was designed so the lowest land surfaces are at eye level with many adult guests, frequently giving the birds a higher vantage point that may further minimize the perception of visitors as threatening. Birds in a mixed-species aviary found primarily in trees, as opposed to those on the ground, did not retreat from visitor pathways with increases in crowd size (Blanchett et al, 2020). Height relative to visitors may impact other taxa as well, such as primates (Chamove et al, 1988).…”

Effects of Visitor Presence and Crowd Size on Zoo-Housed Red Kangaroos (Macropus Rufus) During and After a COVID-19 Closure

“…We expected zoo status to significantly impact behavior and space use following observations in other species (Blanchett et al, 2020;Learmonth et al, 2018;Lockley & Leadbeater, 2005). Inactivity and social proximity were significantly higher when the zoo reopened with limited guest capacity.…”

“…Among some felid species, the presence of visitors has also been linked to decreased activity levels, and increases in visitor density have been related to decreased time spent visible (Mallapur & Chellam, 2002;Sellinger & Ha, 2005;Suárez et al, 2017). Several species of birds and other mammals have also been found to display visitor avoidance behavior (Blanchett et al, 2020;Chiew et al, 2020;Stevens et al, 2013).…”