Mercury (Hg) endangers human and wildlife health globally, primarily due to its release from artisanal small-scale goldmining (ASGM). During gold extraction, Hg is emitted into the environment and converted to highly toxic methylmercuryby microorganisms. In Madre de Dios (MDD), Peru, ASGM dominates the economy and has transformed rainforests intoexpansive deforested areas punctuated by abandoned mining ponds. The aim of this study was to evaluate the use of bats asbioindicators for mercury pollution intensity in tropical terrestrial ecosystems impacted by ASGM. We collected 290 bat fursamples from three post-ASGM sites and one control site in Madre de Dios. Our results showed a wide Hg distribution inbats (0.001 to 117.71 mg/kg) strongly influenced by feeding habits. Insectivorous and piscivorous bats from ASGM sitespresented elevated levels of Hg surpassing the mercury small mammal threshold for small mammals (10 mg/kg). Weobserved the highest reported fur mercury concentrations for insectivorous Neotropical bats reported to date(Rhynchonycteris naso, 117 mg/kg). Our findings further confirm that Hg emissions from ASGM are entering local foodwebs and exposing wildlife species at several trophic levels to higher levels of Hg than in areas not impacted by mining. Wealso found that three bat genera consistently showed increased Hg levels in ASGM sites relative to controls indicatingpotential usefulness as bioindicators of mercury loading in terrestrial ecosystems impacted by artisanal and small-scale goldmining

Urbanization usually reduces bat richness; however, the presence of green areas within cities and peripheral rural areas in arid ecosystems may provide microhabitats for some species. Light pollution is a major feature of urbanization, but its impact on bat behavior appears to be species-specific and previous studies have documented contrasting responses. Moreover, the effect of urbanization on bat species has been poorly studied in arid regions. We assessed the effect of artificial night light intensity (as a proxy of urbanization) on both bat occupancy and the acoustic space used (ASU) in an urbanization gradient in Peruvian central coast, based on passive acoustic recorders. We collected 26,169 recordings from 19 sites which resulted in 579 independent detections of 15 bat species. Variation in both ASU and species richness was best explained by artificial night light intensity. Species-specific effects of the artificial night light intensity based on a multi-species occupancy mod-eling showed that this covariate had a negative effect on occupancy for most of the bat species (12 species). ASU and both observed and posterior bat species richness were positively correlated, suggesting that ASU can be used as a proxy of bat richness. This study provides evidence that both bat richness and occupancy decrease with artificial light intensity; nevertheless , eight species used urban areas, similar to results found in other cities around the world.

Selective logging and host sex effects on the ectoparasitism of small mammals of theSouthern Peruvian Amazon. Little is known about the effect of reduced impact logging on interspeci crelationships, particularly the ectoparasite-host relationship. This study assessed the prevalence, abundance,and diversity of ectoparasites of small mammals in forests with reduced impact logging and control plotsin southeastern Peruvian Amazon. We used Generalized Linear Models to assess the effect of reducedlogging, habitat structure, and host sex on the ectoparasites of the most representative genera: Marmosops,Euryoryzomys, Proechimys , and Carollia . No statistical evidence about an effect of reduced logging on boththe prevalence and diversity of ectoparasites were found. However, we found a positive effect of logging on theabundance of mites (Laelapidae) and ticks (Ixodidae) at individual level for Marmosops spp. and Proechimys spp.respectively; but a negative effect on mite abundance in Euryoryzomys spp. In addition, female rodents had ahigher amount of ectoparasites. On the other hand, the intensity of the bat ies (Streblidae) in individualsof Carollia spp. was lower in logged forests. This study is one of the few to address the effect of reducedlogging on ectoparasitism in small mammals. We suggest expanding the knowledge about the effects ofthese interactions to a speci c level on a seasonal basis, which can provide further information to improveunderstanding of how this anthropogenic activity affects interactions between mammals and their ectoparasites.

Innovative techniques, such as environmental DNA (eDNA) metabarcoding, are now promoting broader biodiversity monitoring at unprecedented scales, due to the reduction in time, presumably lower cost, and methodological efficiency. Our goal was to assess the efficiency of established inventory techniques (live‐trapping grids, pitfall traps, camera trapping, mist‐netting) as well as eDNA for detecting Amazonian mammals. For terrestrial small mammals, we used 32 live‐trapping grids based on Sherman and Tomahawk traps (total effort of 10368 trap‐nights); in addition to 16 pitfall traps (1408 trap‐nights). For bats, we used mist nets at 8 sites (4,800 net hours). For medium and large mammals, we used 72 camera trap stations (5208 camera‐days). We identified vertebrate and mammal taxa based on eDNA analysis (12S region, with V05 and Mamm01 markers) from water samples, including a total of 11 3‐km transects for stagnant water sampling and 7 small streams for running water sampling. A total of 106 mammal species were recorded. Building on sample‐based rarefaction and extrapolation curves, both trapping grids and pitfall were successful, recording 91.16% and 82.1% of the expected species for these techniques (~22 and ~9 species), and 16.98% and 6.60% of the total recorded mammal species, respectively. Mist nets recorded 83.2% of the expected bat species (~48), and 34.91% of the total recorded species. Camera trapping recorded 99.2% of the predicted large and medium‐sized species (~31), and 33.02% of the total recorded species. eDNA recorded 75.4% of the expected mammal species for this technique (~68), and 47.0% of the total recorded species. eDNA resulted in a useful tool that saves on effort and reduces sampling costs. This study is among the first to show the large potential of eDNA metabarcoding for assessing Amazonian mammal communities, providing, in combination with conventional techniques, a rapid overview of mammal diversity with broad applications to monitoring, management and conservation. By including appropriate genetic markers and updated reference databases, eDNA metabarcoding method can be extended to the whole vertebrate community.

There are at least 180 species of bats in Peru. However, there are few studies about ectoparasites of bats, among which the so-called bat flies (Diptera: Streblidae and Nycteribiidae) stand out, with a total of 158 species estimated for the Neotropical region. In Peru, one of the ecological regions with the least information is the
coast. In this study we updated the knowledge of the ectoparasite-host associations in bats from the Peruvian coast, one of the regions of the country with the most degradation and loss of habitat. Five locations in the Piura, Lima and Tacna regions were evaluated. 85 bats belonging to 7 species were captured: 4 from Phyllostomidae, 2 from Molossidae and 1 from Vespertilionidae. Six dipterous species (Diptera: Streblidae) and one Hemiptera species (Hemiptera: Polyctenidae) were found and some of these associations are reported for the first time in the Lima and Piura regions. Anoura peruana is also reported as the host of Anastrebla modestini (Streblidae) in a reproductive colony shared with Platalina genovensium, and for the first time for the Piura region, the coparasitism of the Megistopoda aranea, Aspidoptera phyllostomatis and Metelasmus pseudopterus in a same individual of Artibeus fraterculus.