Adapting to change: transitions in traditional rangeland management of Tibetan yak herders in northwest Yunnan

Tibetan yak herding practices in northwest Yunnan, southwest China have maintained remarkable biological diversity. To learn more about local cultural adaptation to policy changes, we interviewed 37 households in Deqin County on their traditional knowledge, and the changes they have observed in ecological conditions, livestock health, and land management. These villages varied in proximity to main roads, farmland quality, and livelihood options. Herd sizes in Deqin have quadrupled since the 1950s, due to commune era policies and subsequent privatization of livestock. The practice of burning shrubs increased during the communal period but has since decreased due to a burn ban. Herders report that the increase in shrublands invading alpine meadows has reduced livestock forage, reducing the productivity of alpine rangelands and yak health. Butter production has declined by 30 % over the last two decades. Herders are shifting to diversify sources of income when available, but villagers in remote and protected areas continue to depend on livestock for much of their livelihood. Scientific data confirm herder reported ecological changes including increased temperature, decreased snowfall, and accounts of increased erosion (which deserves further study). Climate, policy, and economic incentives have interacted to increase pressure on shrinking alpine meadows and reduce dairy production.     

Modeling spatial patterns in fisheries bycatch: improving bycatch maps to aid fisheries management.

Fisheries bycatch, or incidental take, of large vertebrates such as sea turtles, seabirds, and marine mammals, is a pressing conservation and fisheries management issue. Identifying spatial patterns of bycatch is an important element in managing and mitigating bycatch occurrences. Because bycatch of these taxa involves rare events and fishing effort is highly variable in space and time, maps of raw bycatch rates (the ratio of bycatch to fishing effort) can be misleading. Here we show how mapping bycatch can be enhanced through the use of Bayesian hierarchical spatial models. We compare model-based estimates of bycatch rates to raw rates. The model-based estimates were more precise and fit the data well. Using these results, we demonstrate the utility of this approach for providing information to managers on bycatch probabilities and cross-taxa bycatch comparisons. To illustrate this approach, we present an analysis of bycatch data from the U.S. gill net fishery for groundfish in the northwest Atlantic. The goals of this analysis are to produce more reliable estimates of bycatch rates, assess similarity of spatial patterns between taxa, and identify areas of elevated risk of bycatch.     

PERCOLATION OF LEAD(II) AND CADMIUM(II) THROUGH TWO BENTONITES USED AS LANDFILL LINER

In order to prevent contamination of subsoil and groundwater by leachates containing heavy metals, montmorillonite linings are used on landfill bottoms. It is therefore important to understand ion uptake by this clay. In this study we have performed percolation of lead(II) and cadmium(II) through columns filled firstly with a technical bentonite and then with a reference bentonite. Elution curves provide an evaluation of metals retention. After the percolation step, columns are cut and metal ions are extracted to evaluate influence of side effects and soil depth on metal uptake. Moreover retentions of lead(II) and cadmium(II) are compared.     

Brownfields as a tool for the rejuvenation of land and community

Brownfields have been a powerful force attempting to advance both sustainability and economic development. The author, principally using U.S. examples, advances the belief that the true benefits potentially offered by Brownfields can only be fully realized by using tools such as found in the application of Community Benefit Agreements. In a similar way use of Community-Based Participatory Research frameworks holds out similar promise. The proof of this promise will only be found in the implementation of these models.     

Predicting biodiversity change: outside the climate envelope, beyond the species-area curve

Efforts to anticipate threats to biodiversity take the form of species richness predictions (SRPs) based on simple correlations with current climate and habitat area. We review the major approaches that have been used for SRP, species-area curves and climate envelopes, and suggest that alternative research efforts may provide more understanding and guidance for management. Extinction prediction suffers from a number of limitations related to data and the novelty of future environments. We suggest additional attention to (1) identification of variables related to biodiversity that are diagnostic and potentially more predictable than extinction, (2) constraints on species dispersal and reproduction that will determine population persistence and range shifts, including limited sources or potential immigrants for many regions, and (3) changes in biotic interactions and phenology. We suggest combinations of observational and experimental approaches within a framework available for ingesting heterogeneous data sources. Together, these recommendations amount to a shift in emphasis from prediction of extinction numbers to identification of vulnerabilities and leading indicators of change, as well as suggestions for surveillance tools needed to evaluate important variables and the experiments likely to provide most insight.     

Associative learning of odor with food- or blood-meal by Culex quinquefasciatus Say (Diptera: Culicidae)

The ability of many insects to learn has been documented. However, a limited number of studies examining associative learning in medically important arthropods has been published. Investigations into the associative learning capabilities of Culex quinquefasciatus Say were conducted by adapting methods commonly used in experiments involving Hymenoptera. Male and female mosquitoes were able to learn a conditioned stimulus that consisted of an odor not normally encountered in nature (synthetic strawberry or vanilla extracts) in association with an unconditioned stimulus consisting of either a sugar (males and females) or blood (females) meal. Such information could lead to a better understanding of the ability of mosquitoes to locate and select host and food resources in nature.     

Discordance between age- and size-based criteria of child passenger restraint appropriateness

Objectives: In this study, we sought to accomplish the following objectives: to (1) calculate the percentage of children considered appropriately restrained across 8 criteria of increasing restrictiveness; (2) examine agreement between age- and size-based appropriateness criteria; (3) assess for changes in the percentage of children considered appropriately restrained by the 8 criteria between 2011 (shortly after updates to U.S. guidelines) and 2015.

Methods: Data from 2 cross-sectional surveys of 928 parents of children younger than 12 years old (n = 591 in 2011, n = 337 in 2015) were analyzed in 2017. Child age, weight, and height were measured at an emergency department visit and used to determine whether the parent-reported child passenger restraint was considered appropriate according to 8 criteria. Age-based criteria were derived from Michigan law and U.S. guidelines. Weight, height, and size-based criteria were derived from typical restraints available in the United States in 2007 and 2011. The percentage appropriate restraint use was calculated for each criterion. The kappa statistic was used to measure agreement between criteria. Change in appropriateness from 2011 to 2015 was assessed with chi-square statistics.

Results: Percentage appropriate restraint use varied from a low of 19% for higher weight limits in 2011 to a high of 91% for Michigan law in 2015. Agreement between criteria was slight to moderate. The lowest kappa was for Michigan law and higher weight limits in 2011 (κ = 0.06) and highest for U.S. guidelines and lower weight limits in 2011 (κ = 0.60). Percentage appropriate restraint use was higher in 2015 than 2011 for the following criteria: U.S. guidelines (74 vs. 58%, P < .001), lower weight (57 vs. 47%, P = .005), higher weight (25 vs. 19%, P = .03), greater height (39 vs. 26%, P < .001), and greater size (42 vs. 30%, P = .001).

Conclusions: The percentage of children considered to be using an appropriate restraint varied substantially across criteria. Aligning the definition of appropriate restraint use with current U.S. guidelines would increase consistency in reporting results from studies of child passenger safety in the United States. Potential explanations for the increased percentage of children considered appropriately restrained between 2011 and 2015 include adoption of the updated U.S. guidelines and the use of child passenger restraints with higher weight and height limits.     

Characterizing the child passenger safety workforce in Michigan: A statewide survey in 2015

Objective: In this study, we assessed the number of child passenger safety technicians (CPSTs) in Michigan over 4 years and characterized the CPST workforce in 2015 to identify factors associated with high productivity and longevity in the field.

Methods: We determined the number of CPSTs and those newly certified using lists from the Michigan Office of Highway Safety Planning (OHSP) from 2012 to 2015. We conducted a statewide survey of Michigan CPSTs in October 2015. Analyses were conducted in 2016. The survey assessed demographic characteristics, reasons to enter the field and maintain certification, and motivations to conduct seat checks. We used CPST-reported time devoted to seat checks and average number of seats checked per month to create a composite “activity level” variable. We examined activity levels across several characteristics.

Results: The number of CPSTs ranged from 941 to 980 over the study period, with approximately 200 new certifications annually. In 2015, surveys were started by 496 of 962 eligible CPSTs and 427 submitted complete responses. CPST-instructors had a higher response rate than CPSTs in general (89 vs. 49%, P < .0001). The majority of respondents were women (71%) and self-identified as white (88%). More than one third were 35–44 years old. Just 7% were comfortable checking seats using a language other than English. “Personal reasons” were most often cited motivation for becoming a CPST and maintaining certification. Natural fit/job enhancement were more common reasons to maintain certification than become a CPST. Time and distance had the greatest influence on seat check participation. Perceived need, appointments vs. drop-in, and employer factors were very influential for 10–15% of CPSTs. Few CPSTs considered free food and payments/giveaways very influential. About 40% of respondents were considered high-activity (>24 seats checked/year), one third medium-activity (5 to 24 seats checked/year), and one quarter low-activity (<5 seats checked/year). High-activity CPSTs most commonly reported both being paid and volunteering their time to check seats, worked with a Safe Kids coalition, worked in law enforcement or social services, and had recertified at least once. Motivation to participate in seat checks did not vary with activity level.

Conclusions: Understanding the demographic characteristics and motivations of CPSTs can help Michigan OHSP recruit and retain a workforce dedicated to increasing the safety of child passengers. Agencies hosting seat checks can use these results to align the strategies they employ to incentivize CPSTs to serve in their communities with the factors that have the greatest influence on CPST participation.     

Effects of pond salinization on survival rate of amphibian hosts infected with the chytrid fungus

The chytrid fungus Batrachochytrium dendrobatidis has been implicated in the decline and extinction of amphibian populations worldwide, but management options are limited. Recent studies show that sodium chloride (NaCl) has fungicidal properties that reduce the mortality rates of infected hosts in captivity. We investigated whether similar results can be obtained by adding salt to water bodies in the field. We increased the salinity of 8 water bodies to 2 or 4 ppt and left an additional 4 water bodies with close to 0 ppt and monitored salinity for 18 months. Captively bred tadpoles of green and golden bell frog (Litoria aurea) were released into each water body and their development, levels of B. dendrobatidis infection, and survival were monitored at 1, 4, and 12 months. The effect of salt on the abundance of nontarget organisms was also investigated in before and after style analyses. Salinities remained constant over time with little intervention. Hosts in water bodies with 4 ppt salt had a significantly lower prevalence of chytrid infection and higher survival, following metamorphosis, than hosts in 0 ppt salt. Tadpoles in the 4 ppt group were smaller in length after 1 month in the release site than those in the 0 and 2 ppt groups, but after metamorphosis body size in all water bodies was similar . In water bodies with 4 ppt salt, the abundance of dwarf tree frogs (Litoria fallax), dragonfly larvae, and damselfly larvae was lower than in water bodies with 0 and 2 ppt salt, which could have knock‐on effects for community structure. Based on our results, salt may be an effective field‐based B. dendrobatidis mitigation tool for lentic amphibians that could contribute to the conservation of numerous susceptible species. However, as in all conservation efforts, these benefits need to be weighed against negative effects on both target and nontarget organisms.