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Record-high PFAS contamination levels were recently reported in birds and small mammals from Holloman Lake, a high-salinity wastewater oasis located in southern New Mexico, USA. With additional PFAS screening expanded to surface water, soils, algae, invertebrates, fish, and reptiles, and with a larger number of plants, birds, and mammals also included, we studied the fate, transport, and bioaccumulation of PFAS in the ecosystem and generated contamination profiles both across the water-land interface and for multiple trophic levels. Two degradation products of 6:2 FTS, the short carbon-chain perfluorocarboxylic acids PFHxA (6 carbons) and PFPeA (5 carbons), were the dominant PFAS in surface water in the lake. In contrast, perfluorooctanesulfonic acid (PFOS) was the main PFAS found in sediments along the shoreline, with the length of the fluorinated carbon chain and clay minerals both appearing to play a key role in soil sorption. High soil PFAS concentrations up to 900 m from the edge of the water could not be explained by air transport of contaminated dust and instead seemed related to past inundation events involving contaminated water. Likely due to a combination of factors, there was a marked contrast between PFAS concentrations in and along the main body of the lake vs. the cattail (Typha domiguensis) freshwater wetland immediately to the north. Higher PFAS concentrations along the main body of the lake included an extraordinary 30,000 ng/g ww of PFOS recorded for a composite saltcedar (Tamarix sp.) tissue sample. To date, bioaccumulation has been observed in all species and all types of animal tissue (blood, liver, muscle, and bone) from Holloman Lake. It involves mainly PFOS, followed by perfluorohexanesulfonic acid (PFHxS), with the observed concentrations of PFAS congeners highest in the liver but increasing concomitantly among tissue types. The distinct signatures of three generations of aqueous film-forming foams (AFFFs) were found at Holloman Lake, where contamination is still ongoing. 

Abstract The “small-eared” species group of Urocitellus ground squirrels (Sciuridae: Xerinae: Marmotini) is endemic to the Great Basin, United States, and surrounding cold desert ecosystems. Most specific and subspecific lineages in this group occupy narrow geographic ranges, and some are of significant conservation concern; despite this, current taxonomy remains largely based on karyotypic or subtle pelage and morphological characteristics. Here, we leverage 2 multilocus DNA sequence data sets and apply formal species delimitation tests alongside morphometric comparisons to demonstrate that the most widespread small-eared species (U. mollis Kennicott, 1863 sensu lato; Piute Ground Squirrel) is comprised of 2 nonsister and deeply divergent lineages. The 2 lineages are geographically separated by the east-west flowing Snake River in southern Idaho, with no sites of sympatry currently known. Based on robust support across the nuclear genome, we elevate populations previously attributed to U. mollis from north of the Snake River to species status under the name Urocitellus idahoensis (Merriam 1913) and propose the common name “Snake River Plains Ground Squirrel” for this taxon. We delimit 2 subspecies within U. idahoensis; U. i. idahoensis (Merriam 1913) in western Idaho and U. i. artemesiae (Merriam 1913) in eastern Idaho. Urocitellus idahoensis is endemic to Idaho and has a maximal range area of roughly 29,700 km2 spanning 22 counties but occurs discontinuously across this area. Our work substantially expands knowledge of ground squirrel diversity in the northern Great Basin and Columbia Plateau and highlights the difficulty in delimiting aridland mammals whose morphological attributes are highly conserved. 

Orthohantaviruses are negative-sense RNA viruses that can cause hantavirus cardiopulmonary syndrome (HCPS) in humans. In the United States, Sin Nombre orthohantavirus (SNV) is the primary cause of HCPS, with a fatality rate of 36% and most cases occurring in the southwestern states. The western deer mouse,Peromyscus sonoriensis, is the primary reservoir for SNV; however, it remains unclear if alternative reservoirs exist. We conducted an extensive survey of SNV genetic prevalence in wild-caught small mammal communities throughout New Mexico and observed that 27% of all animals were positive for SNV. Through longitudinal trapping at a site of patient exposure, we found that SNV circulates at a high rate in multiple species over time. Furthermore, we isolated live SNV from tissues and feces from multiple small mammal species, demonstrating infectious virus in alternative and novel reservoirs.Altogether, this work shows that SNV is widely prevalent and persistent throughout New Mexico in multiple small mammal reservoirs that can harbor and shed infectious virus. This encourages future work for additional surveillance efforts and re-evaluates host-species dynamics for New World hantaviruses. 

Abstract Surveillance and monitoring of zoonotic pathogens is key to identifying and mitigating emerging public health threats. Surveillance is often designed to be taxonomically targeted or systematically dispersed across geography, however, those approaches may not represent the breadth of environments inhabited by a host, vector, or pathogen, leaving significant gaps in our understanding of pathogen dynamics in their natural reservoirs and environments. As a case study on the design of pathogen surveillance programs, we assess how well 20 years of small mammal surveys in Panamá have sampled available environments and propose a multistep approach to selecting survey localities in the future. We use >8,000 georeferenced mammal specimen records, collected as part of a long-term hantavirus surveillance program, to test the completeness of country-wide environmental sampling. Despite 20 years of surveillance, our analyses identified a few key environmental sampling gaps. To refine surveillance strategies, we selected a series of core historically sampled localities, supplemented with additional environmentally distinct sites to more completely represent Panama’s environments. Based on lessons learned through decades of surveillance, we propose a series of recommendations to improve strategic sampling for zoonotic pathogen surveillance. 

Amid global challenges like climate change, extinctions, and disease epidemics, science and society require nuanced, international solutions that are grounded in robust, interdisciplinary perspectives and datasets that span deep time. Natural history collections, from modern biological specimens to the archaeological and fossil records, are crucial tools for understanding cultural and biological processes that shape our modern world. At the same time, natural history collections in low and middle-income countries are at-risk and underresourced, imperiling efforts to build the infrastructure and scientific capacity necessary to tackle critical challenges. The case of Mongolia exemplifies the unique challenges of preserving natural history collections in a country with limited financial resources under the thumb of scientific colonialism. Specifically, the lack of biorepository infrastructure throughout Mongolia stymies efforts to study or respond to large-scale environmental changes of the modern era. Investment in museum capacity and training to develop locally-accessible collections that characterize natural communities over time and space must be a key priority for a future where understanding climate scenarios, predicting, and responding to zoonotic disease, making informed conservation choices, or adapting to agricultural challenges, will be all but impossible without relevant and accessible collections. 

Abstract Food web ecology has revolutionized our understanding of ecological processes, but the drivers of food web properties like trophic position (TP) and food chain length are notoriously enigmatic. In terrestrial ecosystems, above‐ and belowground systems were historically compartmentalized into “green” and “brown” food webs, but the coupling of these systems by animal consumers is increasingly recognized, with potential consequences for trophic structure. We used stable isotope analysis (δ 13 C, δ 15 N) of individual amino acids to trace the flow of essential biomolecules and jointly measure multichannel feeding, food web coupling, and TP in a guild of small mammals. We then tested the hypothesis that brown energy fluxes to aboveground consumers increase terrestrial food chain length via cryptic trophic transfers during microbial decomposition. We found that the average small mammal consumer acquired nearly 70% of their essential amino acids (69.0% ± 7.6%) from brown food webs, leading to significant increases in TP across species and functional groups. Fungi were the primary conduit of brown energy to aboveground consumers, providing nearly half the amino acid budget for small mammals on average (44.3% ± 12.0%). These findings illustrate the tightly coupled nature of green and brown food webs and show that microbially mediated energy flow ultimately regulates food web structure in aboveground consumers. Consequently, we propose that the integration of green and brown energy channels is a cryptic driver of food chain length in terrestrial ecosystems. 

Abstract The Convention on Biological Diversity and the Nagoya Protocol on Access and Benefit-Sharing provide an international legal framework that aims to prevent misappropriation of the genetic resources of a country and ensure the fair and equitable sharing of benefits arising from their use. The legislation was negotiated at the behest of lower-income, biodiverse countries to ensure that benefits derived from research and development of genetic resources from within their jurisdictions were equitably returned and could thereby incentivize conservation and sustainable use of biodiversity. Despite good intentions, however, rapid adoption of access and benefit-sharing measures at the national level, often without participatory strategic planning, has hampered noncommercial, international collaborative genetic research with counterproductive consequences for biodiversity conservation and sustainable use. We outline how current implementation of the Convention of Biological Diversity and the Nagoya Protocol affect noncommercial research, such as that conducted in many disciplines in biology, including mammalogy. We use a case study from Brazil, an early adopter, to illustrate some current challenges and highlight downstream consequences for emerging pathogen research and public health. Most emerging pathogens colonize or jump to humans from nonhuman mammals, but noncommercial research in zoonotic diseases is complicated by potential commercial applications. Last, we identify proactive ways for the mammalogical community to engage with the Convention on Biological Diversity and the Nagoya Protocol, through sharing of nonmonetary benefits and working with local natural history collections. Leveraging international scientific societies to collectively communicate the needs of biodiversity science to policy makers will be critical to ensuring that appropriate accommodations are negotiated for noncommercial research. 

Per- and polyfuoroalkyl substances (PFAS) in the environment pose persistent and complex threats to human and wildlife health. Around the world, PFAS point sources such as military bases expose thousands of populations of wildlife and game species, with potentially far-reaching implications for population and ecosystem health. But few studies shed light on the extent to which PFAS permeate food webs, particularly ecologically and taxonomically diverse communities of primary and secondary consumers. Here we conducted >2000 assays to measure tissue-concentrations of 17 PFAS in 23 species of mammals and migratory birds at Holloman Air Force Base (AFB), New Mexico, USA, where wastewater catchment lakes form biodiverse oases. PFAS concentrations were among the highest reported in animal tissues, and high levels have persisted for at least three decades. Twenty of 23 species sampled at Holloman AFB were heavily contaminated, representing middle trophic levels and wetland to desert microhabitats, implicating pathways for PFAS uptake: ingestion of surface water, sediments, and soil; foraging on aquatic invertebrates and plants; and preying upon birds or mammals. The hazardous long carbon-chain form, perfuorooctanosulfonic acid (PFOS), was most abundant, with liver concentrations averaging >10,000 ng/g wet weight (ww) in birds and mammals, respectively, and reaching as high 97,000 ng/g ww in a 1994 specimen. Perfuorohexanesulfonic acid (PFHxS) averaged thousands of ng/g ww in the livers of aquatic birds and littoral-zone house mice, but one order of magnitude lower in the livers of upland desert rodent species. Piscivores and upland desert songbirds were relatively uncontaminated. At control sites, PFAS levels were strikingly lower on average and different in composition. In sum, legacy PFAS at this desert oasis have permeated local aquatic and terrestrial food webs across decades, severely contaminating populations of resident and migrant animals, and exposing people via game meat consumption and outdoor recreation.