No abstract

1. Illegal hunting of ungulates can reduce the prey base of carnivores, which can increase human-carnivore conflict (HCC) through livestock depredation. However, the relationship between ungulate poaching, wild prey abundance and livestock depredation has rarely been empirically studied.2. We surveyed 18 sites across the Hyrcanian forest in northern Iran; a global biodiversity hotspot under pressure from illegal hunting of ungulates, prey depletion, livestock grazing and HCC. We conducted three field surveys across 1,204 km in 93 4 × 4 km cells to count signs of ungulate poaching as well as encounters with livestock and prey species of the Persian leopard Panthera pardus saxicolor and the grey wolf Canis lupus. We documented sheep/goat and cattle depredation from interviews with 201 herders and analysed the effects of illegal hunting of ungulates, forest cover, IUCN categories of reserves, elevation, distance to villages, and wild prey and livestock encounter rates on carnivore depredation rates using generalized linear models.3. Illegal hunting of ungulates was the most influential depredation predictor. An increase in the illegal hunting of ungulates by one sign/km significantly increased depredation by up to four times. We also found significantly lower levels of ungulate poaching in national parks (IUCN category II) compared to protected areas (V), wildlife refuges (IV) and no-hunting areas, though poaching signs were frequently found in most cells (58%). Encounters with livestock was inversely linked to wild prey species, but positively coupled with signs of ungulate poaching. 4. Synthesis and applications. Our study reveals that: (a) an increase in the intensity of illegal hunting of ungulates can intensify livestock depredation by carnivores; (b) future efforts in reducing human-carnivore conflict to acceptable levels require a combination of law enforcement, prey recovery approaches and mitigation measures; (c) it is essential to understand the root causes of poaching to help minimize human-carnivore conflict (HCC). K E Y W O R D Sgrey wolf, human-carnivore conflict, illegal hunting, livestock, Persian leopard, poaching, protected areas, ungulate | 367Journal of Applied Ecology SOOFI et al.

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.

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.

In order to investigate bioaccumulation of mercury in Iranian coastal waters fish, tiger tooth croaker (Otolithes ruber) and yellowspotted trevally (Carangoides fulvoguttatus) from the Gulf of Oman and grass carp (Ctenopharyngodon idella) and silver carp (Hypophthalmichthys molitrix) from Zabol Chahnimeh reservoirs were sampled in May 2012. In these ecosystems, total mercury concentrations were measured in muscle and gill of these four fish species. Both regions did not reveal a significant difference. In H. molitrix and O. ruber, mercury concentrations in gill increased with increasing length (H. molitrix, r = 0.94, p < 0.005; O. ruber, r = 0.94, p > 0.005) and weight (H. molitrix, r = 0.94, p < 0.005; O. ruber, r = 0.82, p > 0.04). Generally, mercury levels in the analysed fish samples were higher than WHO, FDA and US-EPA legal limits.