FRONTIER AREAS, RESOURCES, AND DEVELOPING NATIONS: THE CASE OF GUATEMALA

The conscientious and planned integration of frontier areas into the national economy can at least partially alleviate both environmental and economic problems that are common to many developing countries. Full development of the agricultural potential of frontier areas can lessen the environmental deterioration often found in traditionally settled regions. Exploitation of mineral resources, in particular energy resources, can lessen economic burdens associated with increased costs of imported energy. The authors examine how recent international developments have spurred the government of Guatemala to undertake measures designed to develop a previously underutilized region. The short term negative consequences of increased costs for imported grains and petroleum may well have a positive result in the long term insofar as they lead to more balanced and rational use of land and resources.     

Interspecific Variation in Susceptibility of Frog Tadpoles to the Pathogenic Fungus Batrachochytrium dendrobatidis

Abstract:  As part of an overall biodiversity crisis many amphibian populations are in decline throughout the world. Numerous causes have been invoked to explain these declines. These include habitat destruction, climate change, increasing levels of ultraviolet radiation, environmental contamination, and the introduction of non-native species and diseases. Several types of pathogens have been implicated in contributing to amphibian population declines: viruses, bacteria, oomycetes, and fungi. One particular fungus, the chytridiomycete Batrachochytrium dendrobatidis may have caused amphibian population declines in several regions. This pathogen causes chytridiomycosis, which is fatal to newly metamorphic and adult amphibians of certain species. We present experimental evidence that larval stages may also be susceptible to exposure to Batrachochytrium . There was, however, differential sensitivity to B. dendrobatidis in larvae we examined. In laboratory experiments, larval western toads (  Bufo boreas ) exposed to B. dendrobatidis experienced increased mortality and behaviors that suggested they were affected by exposure compared with unexposed control tadpoles. Larvae of Cascades frogs (  Rana cascadae ), bullfrogs ( R. catesbeiana ), and Pacific treefrogs ( Hyla regilla ) did not die after exposure to Batrachochytrium and appeared to behave normally. R. cascadae larvae exposed to B. dendrobatidis , however, showed an increase incidence in mouthpart abnormalities, a characteristic effect of chytridiomycosis, compared with unexposed controls. These results show that Batrachochytrium can negatively affect some species of amphibians at the larval stage and not others. The implications of interspecific variation in susceptibility to fungal infection are broad.     

Incorporating Collateral Data in Conservation Biology

Abstract:  Conservation biologists often need to set ecological modeling assumptions or estimate parameters from sparse data. In some cases this problem can be addressed by incorporating data from closely related species or from the same species at different sites (i.e., collateral data). Currently no structured methods exist for incorporating such information. An analogous problem in Actuarial science is to set premium rates in situations with little direct data on claim frequency or size. The rates are estimated using actuarial credibility theory, which incorporates collateral data with the direct data. actuarial credibility theory combined with the actuarial control cycle financial management process also provides an adaptive mechanism for updating assumptions. This theory may have some utility for ecologists wanting to incorporate collateral data in an adaptive management framework, a companion to approaches such as Bayesian updating. We describe the historical development of actuarial credibility theory from early ad hoc methods to empirical Bayes approaches. We explore some of the theory's strengths, such as relative simple formulae for incorporation collateral data, and we explore some of the theory's weaknesses, such as the use of the best linear approximation to the Bayes estimate. We illustrate potential applications of the theory using an example on the mortality rate of the Powerful Owl (  Ninox strenua ).     

Maintaining Volunteer Commitment to Local Watershed Initiatives

Australia's Landcare program is advanced as a successful international example of local watershed groups and governments working together to improve natural resource management. One of the aspects considered critical in the success of watershed groups is engaging widespread participation. This paper draws on two regional surveys that explored burnout, or loss of engagement, among Landcare participants in the state of Victoria using the Maslach Burnout Inventory. Survey findings indicated that a large proportion of respondents were experiencing high burnout in terms of low personal accomplishment and suggested that there was potential for burnout to increase. The authors suggest that the expectations of watershed groups must be based around a realistic assessment of the capacity for volunteer groups to deliver improved environmental and social outcomes.     

Terrestrial Reserve Networks Do Not Adequately Represent Aquatic Ecosystems

Abstract: Protected areas are a cornerstone of conservation and have been designed largely around terrestrial features. Freshwater species and ecosystems are highly imperiled, but the effectiveness of existing protected areas in representing freshwater features is poorly known. Using the inland waters of Michigan as a test case, we quantified the coverage of four key freshwater features (wetlands, riparian zones, groundwater recharge, rare species) within conservation lands and compared these with representation of terrestrial features. Wetlands were included within protected areas more often than expected by chance, but riparian zones were underrepresented across all (GAP 1–3) protected lands, particularly for headwater streams and large rivers. Nevertheless, within strictly protected lands (GAP 1–2), riparian zones were highly represented because of the contribution of the national Wild and Scenic Rivers Program. Representation of areas of groundwater recharge was generally proportional to area of the reserve network within watersheds, although a recharge hotspot associated with some of Michigan's most valued rivers is almost entirely unprotected. Species representation in protected areas differed significantly among obligate aquatic, wetland, and terrestrial species, with representation generally highest for terrestrial species and lowest for aquatic species. Our results illustrate the need to further evaluate and address the representation of freshwater features within protected areas and the value of broadening gap analysis and other protected‐areas assessments to include key ecosystem processes that are requisite to long‐term conservation of species and ecosystems. We conclude that terrestrially oriented protected‐area networks provide a weak safety net for aquatic features, which means complementary planning and management for both freshwater and terrestrial conservation targets is needed.     

Impact of the Graduated Driver Licensing Program in Nova Scotia

A comprehensive evaluation of the Nova Scotia graduated licensing program was conducted. This program was implemented on October 1, 1994 and applies to all novice drivers, regardless of age. It spans 2 1/2 years in two stages: a 6-month learner phase, followed by a 24-month newly licensed driver phase. During both phases several driving restrictions apply, most notably a requirement for adult supervision at all times in the learner phase and a night driving restriction from midnight to 5 a.m. in the newly licensed driver phase. The evaluation of this program used a series of increasingly refined analyses that controlled for the influence of other explanatory variables. All the analyses showed that the graduated licensing program in Nova Scotia was associated with a significant reduction in crashes. For drivers age 16, there was a 24 percent decrease in total crashes during the first full year of the program and a 37 percent reduction during the first 3 years of the program. Comparable decreases occurred in injury crashes. Improvements also were observed for all novice drivers, not just those who are young - there was a 19 percent decrease in the crash rate for all novice drivers. Comparisons with results from other graduated licensing programs indicate the Nova Scotia program has been more effective than others in reducing crashes.     

Views of Parents of Teenagers About Graduated Licensing After Experience with the Laws

Parents of 15 year-olds in Florida and Connecticut were first interviewed in 1996 about their views concerning new licensing requirements in their states. Connecticut had introduced a 6-month learner's permit requirement, effectively increasing the licensing age from 16 years to 16 years, 6 months (16 years, 4 months with driver education). Florida enacted a 6-month learner's permit period plus a night driving restriction for 16 and 17 year-olds. In 1996, parents were very supportive of the new requirements, particularly the minimum permit period and nighttime restrictions, even though they recognized they would be inconvenienced to some extent. The same parents were interviewed again in 1999, after most of their teenagers had obtained driver's licenses, and were even more supportive than before of the additional restrictions. Few parents reported that the laws inconvenienced them, and less than 20 percent said the laws had made it harder for their teenagers to get jobs. Furthermore, many were in favor of additional requirements, such as teenage passenger restrictions, not currently part of their states” laws. These findings should encourage other states to proceed with graduated licensing systems or to augment systems already in place.     

Criteria for Oil Spill Recovery: A Case Study of the Intertidal Community of Prince William Sound, Alaska, Following the Exxon Valdez Oil Spill

Marine intertidal organisms in Prince William Sound were exposed to crude oil following the T/V Exxon Valdez oil spill in 1989. The intertidal communities were also subjected to mechanical disturbance during invasive oil spill remediation and cleanup efforts. Using monitoring data collected from 1989 to 1997, impacts and eventual recovery were assessed at oiled but uncleaned sites and oiled and cleaned study areas. A statistical model where recovery was defined as parallelism between the time profiles at control and oiled sites was evaluated. Statistical analysis and graphical presentations of the data suggest intertidal epibiota communities recovered from the oil spill by 1992 at the oiled sites and by 1994 at the oiled and remediated sites. Empirical data from the intertidal monitoring program supports the use of tests of parallelism in evaluating recovery and the need to avoid simply the comparison of sample means from control and oiled sites.