Date of Award
Doctor of Philosophy (PhD)
Wildlife and Fisheries Biology
Bowerman, William W
Bridges , Willian C
Foltz , Jeffrey W
The first component of the study examined the fate of balloons after release to determine aspects of where, in what state, and how long they persist in the environment to assess potential risk of exposure to wildlife. Tagged balloons from sporting events gave estimates of mean distances traveled from releases. Effects on the structural integrity of the latex balloon as it reaches the upper atmosphere were also tested to determine the physical state when fragments landed. Degradation studies were conducted to determine the length of time latex can persist in the environment after exposure to various environmental conditions (sun, shade, lentic and lotic water). Motion activated cameras were used to determine which species are attracted to balloons where they occur in the environment. Few tagged balloons released (40 of 5600) were recovered. It was found that balloons traveled a median distance of 33.8 km (fÝ = 70 km) from point of origin. From atmospheric trials, approximately 12% burst into small pieces as previously described, and 81% were recovered with half the balloon mass intact. Degradation studies indicate latex breaks down to a brittle stage within 8-10 weeks when exposed to air. Balloons submerged in water degrade more slowly, retaining elasticity beyond five months. Frequency of camera activation by wildlife showed no significant difference between visitation of balloon plots and controls.
The second phase of the study examined the potential threat that latex balloon fragments may represent to wildlife through ingestion. Trial species of Japanese Quail (Coturnix coturnix japonica ), Red-eared Sliders ((Trachemys scripta elegans) and Channel Catfish ((Ictalurus punctatus) were model species representing wildlife taxa potentially impacted by latex balloons. Latex fragments were offered twice weekly for four weeks, and blood samples were taken pre and post-trial to discern any change in heterophil to lymphocyte (H/L) or neutrophil to lymphocyte (N/L) ratios as an indicator of physiological stress from ingestion. Latex fragments were offered for consumption for four weeks. Blood samples were taken pre- and post-trial to discern any change in heterophil to lymphocyte (H/L) or neutrophil to lymphocyte (N/L) ratios as an indicator of physiological stress from ingestion. Weight was recorded weekly. Test organisms were euthanized at four weeks and necropsies were performed to examine for digestive tract anomalies. In summary, no significant difference was detected in H/L ratios pre- and post-trial for (C. Japonica or for T. scripta elegans. There was a significant decrease in N/L ratios from pre- to post-trial for (I. punctatus. Weight increased significantly for sub-adult quail and catfish fingerlings during the study, however no significant change of weight was observed in adult turtles. Necropsies did not reveal any digestive anomalies in quail or catfish; although turtles did show substantial accumulation of latex fragments in three of 14 specimens (21%). Results of this study suggest that consumption of latex balloon fragments may not pose a threat to many wildlife species.
The third aspect of the study sought to evaluate public opinion concerning mass latex balloon releases and document any observed effects that natural latex balloons have on wildlife or the environment. Surveys were conducted on sporting event patrons, natural resources officials, and NGOs. Patrons attending Clemson University home football games participated in a survey that focused on relevance of releases as a pregame activity and perceived harm they might pose to the environment. Natural resources officials and NGO members were surveyed to ascertain opinions of possible effects of balloon releases on wildlife, and to provide documentation of harm caused to wildlife as a result of interaction with latex balloons. Balloon releases during pre-game were of less value to sports patrons than other aspects of the game day event. Forty-two percent believed latex balloon releases are dangerous for the environment with the main reason cited as a danger to wildlife (37%). Approximately 50% ranked protection of the environment as ¡§important¡¨ as opposed to ¡§very important¡¨ or ¡§not important¡¨. The majority of natural resources officials and NGO members responded as not having encountered animals injured by latex balloons (73%), and 90% had not observed any animal mortality due solely to latex balloons. Strings were responsible for 67% of the injuries reported by both groups; however 87% consider balloons dangerous for the environment. Sea turtles were the most cited species affected by latex balloons (53%), followed by shore birds (40%).
Results from the different aspects of this research enhances our understanding of how far latex balloons can travel after release, the physical state when they land, how long they persist, and which species are attracted to them and in what frequency. This study also suggests that consumption of latex materials may not pose a threat to many species, while further long-term studies on turtles may be necessary. Public opinion is varied, although those that work in a field related to natural resources management or NGOs tended to believe that release of latex balloons warranted concern for the safety of wildlife, without any direct observations of harm.
Irwin, Stephan, "Mass Latex Balloon Releases and the Potential Effects on Wildlife" (2012). All Dissertations. 959.