Application of the integrated threat theory to conservation law enforcement

Interactions between law enforcement agents in conservation (e.g., rangers) and illegal resource users (e.g., illegal hunters) can be violent and sometimes fatal, which negatively affects conservation efforts and people's well-being. Models from social psychology, such as integrated threat theory (ITT) (intergroup interactions shape intergroup emotions, prejudices and perceived threats leading to hostile attitudes or behaviors between groups), are useful in addressing such interactions. Conservation approaches relying mainly on law enforcement have never been investigated using this framework. Using a structured questionnaire, we collected data from 282 rangers in protected and unprotected areas (n = 50) in northern Iran. We applied Bayesian structural equation modeling in an assessment of rangers' affective attitudes (i.e., emotions or feelings that shape attitudes toward a person or object) toward illegal hunters in an ITT framework. Rangers' positive perceptions of illegal hunters were negatively associated with intergroup anxiety (emotional response to fear) and negative stereotypes about a hunter's personality, which mediated the relationship between negative contact and affective attitudes. This suggests that negative contact, such as verbal abuse, may lead rangers to perceive illegal hunters as arrogant or cruel, which likely forms a basis for perceived threats. Rangers' positive contact with illegal hunters, such as playing or working together, likely lowered their perceived realistic threats (i.e., fear of property damage). Perceived realistic threats of rangers were positively associated with negative contacts (e.g., physical harm). The associations we identified suggest that relationships based on positive interactions between rangers and illegal hunters can reduce fear and prejudice. Thus, we suggest that rangers and hunters be provided with safe spaces to have positive interactions, which may help lower tension and develop cooperative conservation mechanisms.

Joint toxicity of cadmium and fenpyroximate on two earthworms: Interspecific differences, subcellular partitioning and biomarker responses

Cadmium (Cd) and fenpyroximate are common soil contaminants found together in the field, but their combined toxicity to terrestrial invertebrates has not been studied. Therefore, earthworms Aporrectodea jassyensis and E. fetida were exposed into Cd (5, 10, 50 and 100 μg/g) and fenpyroximate (0.1, 0.5, 1, and 1.5 μg/g) and their mixture, and multiple biomarker responses (mortality, catalase (CAT), superoxide dismutase (SOD), total antioxidant activity (TAC), lipid peroxidation (MDA), protein content, weight loss and subcellular partitioning) were determined to estimate health status and mixture effect. MDA, SOD, TAC, and weight loss were significantly correlated with Cd in total internal and debris (p < 0.01). Fenpyroximate altered the subcellular distribution of Cd. It appears that maintaining Cd in a non-toxic form was the earthworms' primary Cd detoxification strategy. CAT activity was inhibited by Cd, fenpyroximate, and their combined presence. BRI values for all treatments indicated a major and severe alteration in earthworm's health. The combined toxicity of Cd and fenpyroximate was greater than the toxicity of either substance alone. According to EAI, all combined treatments exhibited a clear antagonistic effect. In general, the sensitivity of A. jassyensis was greater than that of E. fetida.

Trace element concentrations in water and Clupeonella cultriventris caspia in the Southern Caspian Sea and Assessment of Potential Risk to Human Health

Despite the fishing pressure on common kilka (Clupeonella cultriventris caspia) and the importance of the Caspian Sea, there are little data on trace element levels in those. Therefore, the concentrations of 27 trace elements were measured in water (n=15) and C. cultriventris (n=1050) collected from the southern Caspian Sea. The concentrations of Cd, Hg, and Zn in the water exceeded permissible limits and posed potential ecological risks to the aquatic biota, especially in the southeastern region of the Caspian Sea. The estimated daily intakes of As, Cd, Co, Hg, Mn, Pb, Sb, and V from the consumption of C. cultriventris were higher than the acceptable daily intake recommended by the JECFA and USEPA. However, the target hazard quotients and hazard index values were lesser than one. It appears that C. cultriventris provides a small amount of essential element nutrition for consumers. In conclusion, this study revealed that consumers are exposed to As, Co, Hg, Mn, Mo, Sb, and, V through the consumption of C. cultriventris. Also, the concentrations of Cd, Hg, and Zn in water showed significant ecological risk.

Metal Concentrations in Tissues of Gadwall and Common Teal from Miankaleh and Gomishan International Wetlands, Iran

Miankaleh and Gomishan International Wetlands are important wintering areas for waterbirds in the Caspian Sea region. Previous studies revealed increased exposure to metals in some species of waterbirds using these wetlands. In this study, we examined concentrations of cadmium (Cd), chromium (Cr), iron (Fe), lead (Pb), and zinc (Zn) in kidneys, liver, and pectoral muscle of wintering Gadwall (Anas strepera) and Common Teal (Anas crecca) collected in 2012. In addition, we measured concentrations of these elements in water and sediments from the collection sites. The genders differed in only one element/tissue combination, i.e., concentrations of Fe were greater in the livers of males. Concentrations of elements observed in Gadwall were generally higher than in Common Teal; only renal Cr and muscle Zn did not differ between species. Mean Cd concentrations in Gadwall exceeded background levels, reaching 1.94 μg/g ww in kidneys and 1.09 μg/g ww in liver. Similarly, Pb concentrations in Gadwall were also elevated (4.14 μg/g ww in kidneys, 3.22 μg/g ww in liver). Concentrations of other metals were within ranges commonly found in waterfowl. Concentrations of elements in the environment were elevated above background and comparable with the data obtained for this region by other scientists. However, these levels were deemed to not be great enough to pose an acute health risk to waterfowl. Given increased concentrations of some metals in duck tissues, further inquiry into the source of the exposure is needed for this area.

Mercury concentration in the feathers of birds from various trophic levels in Fereydunkenar International wetland (Iran)

Mercury (Hg) is one of the main global pollutants that may biomagnify in food nets, especially in wetlands. Birds may be useful in the biomonitoring of Hg in such habitats and may even serve in vivo samples. This paper examined Hg concentration in the feathers of seven bird species foraging on Fereydunkenar International wetland (in 2013). Mean Hg concentrations found ranged from 0.005 ± 0.002 μg g^-1 d.w. (dry weight) (Common hoopoe) to 0.38 ± 0.047 μg g^-1 d.w. (Greylag goose). Significant differences in Hg concentrations were noted between bird species as well as between trophic levels (one-way ANOVAs, p < 0.001). The decrease in mean Hg concentration in feathers was as follows: Greylag goose > Northern pintail ≥ Gadwall ≥ Mallard > Eurasian bittern ≥ Little bittern > Common hoopoe. The position in the trophic chain significantly influenced Hg concentrations, which were the highest in omnivorous species. Hg concentrations may also depend on migration routes and breeding habitats, but the evaluation of the exposure exceeds the ambit of this paper. The Hg concentrations found generally were low, lower than the safe thresholds reported in the literature.

Mercury levels in avian feathers from different trophic levels of eight families collected from the northern region of Iran

Mercury levels were determined in feathers from 83 birds belonging to 18 species (eight families), all collected from the northern region of Iran. Mercury levels were evaluated in relation to taxonomic affiliation and feeding strategies. Mercury levels in the feathers were between 0.05 ± 0.01 and 1.10 ± 0.15 μg g(-1) dry weight, and there was a significant effect of taxonomic groups (p < 0.05). The highest mercury levels were found in Accipitridae, and mercury was not detected in the family Upupidae. The pattern for mercury levels was Accipitridae > Pelecanidae > Sternidae > Ardeidae > Anatidae > Rallidae > Phasianidae (p < 0.05). Significant differences (p < 0.05) in the mean mercury levels were found among species as a function of feeding method and trophic level. Mercury levels were highest in the carnivorous species and lowest in the herbivorous species. Mercury levels in feathers of birds in this study were generally below the thresholds reported to affect reproduction.