Level and precision of behavioural thermoregulation in the bearded dragon, Pogona vitticeps : effects of hypoxia and environmental thermal quality /

Most metabolic functions are optimized within a narrow range of body temperatures, which is why thermoregulation is of great importance for the survival and overall fitness of an animal. It has been proposed that lizards will thermoregulate less precisely in low thermal quality environments, where the costs associated with thermoregulation are high; in the case of lizards, whose thermoregulation is mainly behavioural, the primary costs ofthermoregulation are those derived from locomotion. Decreasing thermoregulatory precision in costly situations is a strategy that enhances fitness by allowing lizards to be more flexible to changing environmental conditions. It allows animals to maximize the benefits of maintaining a relatively high body temperature while minimizing energy expenditure. In situations where oxygen concentration is low, the costs of thermoregulation are relatively high (i.e. in relation to the amount of oxygen available for metabolic functions). As a result, it is likely that exposures to hypoxic conditions induce a decrease in the precision of thermoregulation. This study evaluated the effects of hypoxia and low environmental thermal quality, two energetically costly conditions, on the precision and level of thermoregulation in the bearded dragon, Pogona vitticeps, in an electronic temperature-choice shuttle box. Four levels of hypoxia (1O, 7, 5 and 4% 02) were tested. Environmental thermal quality was manipulated by varying the rate of temperature change (oTa) in an electronic temperature-choice shuttle box. Higher oT a's translate into more thermally challenging environments, since under these conditions the animals are forced to move a greater number of times (and hence invest more energy in locomotion) to maintain similar temperatures than at lower oTa's. In addition, lizards were tested in an "extreme temperatures" treatment during which air temperatures of the hot and cold compartments of the shuttle box were maintained at a constant 50 and 15°C respectively. This was considered the most thermally challenging environment. The selected ambient (T a) and internal body temperatures (Tb) of bearded dragons, as well as the thermoregulatory precision (measured by the central 68% ofthe Ta and T b distribution) were evaluated. The thermoregulatory response was similar to both conditions. A significant increase in the size of the Tb range, reflecting a decrease in thermoregulatory precision, and a drop in preferred body temperature of ~2 °C, were observed at both 4% oxygen and at the environment of lowest thermal quality. The present study suggests that in energetically costly situations, such as the ones tested in this study, the bearded dragon reduces energy expenditure by decreasing preferred body temperature and minimizing locomotion, at the expense of precise behavioural thermoregulation. The close similarity of the behavioural thermoregulatory response to two very different stimuli suggests a possible common mechanism and neuronal pathway to the thermoregulatory response.

Socially Constructed Environmental Issues and Sport: A Content Analysis of Ski Resort Environmental Communications

Due to the impact of sport on the natural environment (UN, 2010), it is important to examine the interplay between environmental issues and sport (Hums, 2010, Mallen & Chard, 2011; Nauright & Pope, 2009; Ziegler, 2007). This research content analyzed 82 ski resort environmental communications (SRECs). These communications were rated for their prominence, breadth, and depth using the delineation of environmental issues provided by the Sustainable Slopes Program (SSP) Charter. This data was compared to the resorts’ degree of environmentally responsible action as rated by the Ski Area Citizens’ Coalition (SACC). An adaptation of Hudson and Miller's (2005) model was then used to classify the ski resorts as inactive, reactive, exploitive, or proactive in their environmental activities. Recommendations have been made for standardization and transparency in environmental disclosures and an environmental management system to aid ski resorts in moving from ad hoc processes to a systematic and comprehensive framework for improving environmental performance.

Niagara River (Ontario) Remedial Action Plan fonds, 1984-1997, n.d.

The Niagara River Remedial Action Plan was part of an initiative to restore the integrity of the Great Lakes Basin ecosystem. In 1972, the Great Lakes Water Quality Agreement was signed by both Canada and the United States to demonstrate their commitment to protecting this valuable resource. An amendment in 1987 stipulated that Remedial Action Plans (RAPs) be implemented in 43 ecologically compromised areas known as Areas of Concern. The Niagara River was designated as one of these areas by federal and provincial governments and the International Joint Commission, an independent and binational organization that deals with issues concerning the use and quality of boundary waters between Canada and the United States. Although the affected area included parts of both the Canadian and American side of the river, Remedial Action Plans were developed separately in both Canada and the United States. The Niagara River (Ontario) RAP is a three-stage process requiring collaboration between numerous government agencies and the public. Environment Canada, the Ontario Ministry of the Environment, and the Niagara Peninsula Conservation Authority are the agencies guiding the development and implementation of the Niagara River (Ontario) RAP. The first stage is to determine the severity and causes of the environmental degradation that resulted in the location being designated an Area of Concern; the second stage is to identify and implement actions that will restore and protect the health of the ecosystem; and the third stage is to monitor the area to ensure that the ecosystem’s health has been restored. Stage one of the RAP commenced in January 1989 when a Public Advisory Committee (PAC) was established. This committee was comprised of concerned citizens and representatives from various community groups, associations, industries and municipalities. After several years of consultation, the Niagara River (Ontario) Remedial Action Plan Stage 2 Report was released in 1995. It contained 16 goals and 37 recommendations. Among them was the need for Canadians and Americans to work more collaboratively in order to successfully restore the water quality in the Niagara River. Stage three of the Niagara River (Ontario) RAP is currently ongoing, but it is estimated that it will be completed by 2015. At that point, the Niagara River Area of Concern will be delisted, although monitoring of the area will continue to ensure it remains healthy.