Tracie Seimon

• PhD
• Director of WCS Molecular Laboratory at Wildlife Conservation Society

The Cordillera Vilcanota in southern Peru is the second largest glacierized range in the tropics and home to one of the largest high-alpine lakes, Sibinacocha (4,860 m). Here, Telmatobius marmoratus (marbled water frog), Rhinella spinulosa (Andean toad), and Pleurodema marmoratum (marbled four-eyed frog) have expanded their range vertically within...

Species composition in high-alpine ecosystems is a useful indicator for monitoring climatic and environmental changes at the upper limits of habitable environments. We used environmental DNA (eDNA) analysis to document the breadth of high-alpine biodiversity present on Earth’s highest mountain, Mt. Everest (8,849 m a.s.l.) in Nepal’s Khumbu region....

We present the first report of Pallas’s cat Otocolobus manul in eastern Nepal, within Sagarmatha National Park, Mount Everest Region, based on genetic evidence from scat samples. We collected the samples from two locations 6 km apart at 5,110 and 5,190 m elevation. DNA metabarcoding analysis identified two individuals from the collect- ed samples....

All species of big cats, including tigers, cheetahs, leopards, lions, snow leopards, and jaguars, are protected under the Convention on the International Trade in Endangered Species (CITES). This is due in large part to population declines resulting from anthropogenic factors, especially poaching and the unregulated and illegal trade in pelts, bone...

Swinhoe's (or Yangtze) giant softshell turtle (Rafetus swinhoei) is a large, critically endangered freshwater turtle and considered among the rarest species in the world. As of 2024, only two individuals have been confirmed to remain alive, one at the Suzhou Zoo in China and one in Xuan Khanh Lake, Viet Nam. The only hope for the long‐term survival...

We identified a novel herpesvirus in 2 deceased captive blue penguins ( Eudyptula minor). Moderate-to-severe myocardiocyte atrophy and necrosis, and eosinophilic intranuclear inclusion bodies (INIBs), were seen in myocardiocytes in one bird; reticuloendothelial (RE) cell INIBs and multifocal RE cell necrosis were seen in both birds. The histologic...

Swinhoe's (or Yangtze) giant softshell turtle (Rafetus swinhoei) is a large, critically endangered freshwater turtle and considered among the rarest species in the world. As of 2024, only two individuals have been confirmed to remain alive, one at the Suzhou Zoo in China and one in Xuan Khanh Lake, Viet Nam. The only hope for the long-term survival...

Lower respiratory tract disease associated with mycoplasmal infection was detected in a free-ranging bog turtle (Glyptemys muhlenbergii) from New Jersey, US. The presence of a mycoplasmal organism was confirmed by PCR and electron microscopy. Fluid-filled lungs were observed grossly, and there was proliferative pneumonia on histopathology. Respirat...

The endemic Grand Cayman or blue iguana (Cyclura lewisi) is endangered. Beginning in 2015 significant morbidity and mortality occurred in captive and wild blue iguanas within Grand Cayman's Queen Elizabeth II Botanic Park (QEIIBP). Investigation identified a novel Helicobacter sp., provisionally named Helicobacter sp. Grand Cayman Blue Iguana 1 (GC...

Microbial communities in alpine environments >7,500 m.a.s.l. have not been well studied using modern cultivation-independent sequencing approaches due to the challenges and danger associated with reaching such high elevations. For this reason, we know little about the microorganisms found in sediments on Earth’s tallest mountains, how they reach th...

The Burmese roofed turtle (Batagur trivittata), a critically endangered freshwater turtle, is endemic to Myanmar. Once thought to be extinct, remnant wild populations were discovered in 2001 and limited captive individuals identified in pagoda ponds or confiscated from fishers in Myanmar. These and their offspring are maintained in five facilities...

Amoebiasis is a significant protozoal disease of reptiles causing nonspecific clinical signs including diarrhea, anorexia, and lethargy. It frequently results in acute death. Investigation of the pathophysiology of amoebiasis in reptiles has been hampered by the inability to accurately identify amoeba to the species level using conventional techniq...

Sarcocystosis was diagnosed in a captive flock of thick-billed parrots (Rhynchopsitta pachyrhyncha) at the Wildlife Conservation Society's Queens Zoo. Since the index case in 2005, 45% of mortalities in birds over 30 days of age were due to sarcocystosis. Sarcocystis falcatula was repeatedly identified as the causative agent. The disease predominan...

The Blue Iguana Recovery Programme maintains a captive breeding and head-starting program for endangered Grand Cayman blue iguanas (Cyclura lewisi) on Grand Cayman, Cayman Islands. In May 2015, program staff encountered two lethargic wild Grand Cayman blue iguanas within the Queen Elizabeth II Botanic Park (QEIIBP). Spiral-shaped bacteria were iden...

Significance The decline and progressive fragmentation of many threatened populations increase extinction vulnerability due to outbreaks of infectious disease. Vaccination is one of the few tools available to mitigate these threats, but its use is often hampered by insufficient epidemiological understanding and historic controversies over endangere...

The National Geographic and Rolex Perpetual Planet Everest Expedition is a multidisciplinary project dedicated to understanding climate change and its impacts, improving climate predictions, and providing a framework for future research in mountain environments. This issue of One Earth offers a first look at the science emerging from the expedition...

Canine distemper virus (CDV) is a multi-host pathogen that can cause significant mortality in domestic, wild terrestrial and marine mammals. It is a major conservation threat in some endangered species. Infection can result in severe respiratory disease and fatal encephalitis. Diagnosis and disease monitoring in wildlife, and differentiation of CDV...

The ability to sequence a variety of wildlife samples with portable, field-friendly equipment will have significant impacts on wildlife conservation and health applications. However, the only currently available field-friendly DNA sequencer, the MinION by Oxford Nanopore Technologies, has a high error rate compared to standard laboratory-based sequ...

Vector-borne Plasmodium spp. infect a wide range of bird species. Although infections may be asymptomatic, certain genera, especially those that evolved in regions without endemic malaria, appear particularly susceptible to symptomatic disease, leading to morbidity and mortality. High mortalities associated with malaria infections have been documen...

1. The ability to sequence a variety of wildlife samples with portable, field-friendly equipment will have significant impacts on wildlife conservation and health applications. However, the only currently available field-friendly DNA sequencer, the MinION by Oxford Nanopore Technologies, has a high error rate compared to standard laboratory-based s...

The once abundant Burmese star tortoise ( Geochelone platynota) was functionally extirpated from Myanmar largely due to exploitation for wildlife trade markets. Geochelone platynota is endemic to the dry zone of central Myanmar, a desert-like region formed by the rain shadow of the western mountains. To prevent biological extinction, ex situ captiv...

Sarcocystis falcatula is a well-known cause of fatal pneumonia in some birds, particularly Old World psittacines. Here we describe fatal sarcosystosis due to S. falcatula in 3 penguins (Family Spheniscidae) under managed care, including one African penguin (Spheniscus demersus), and two Southern rockhopper penguins (Eudyptes chrysocome). Randomly d...

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The huemul (Hippocamelus bisulcus) is an endangered cervid endemic to southern Argentina and Chile. Here we report foot lesions in 24 huemul from Bernardo O’Higgins National Park, Chile, between 2005 and 2010. Affected deer displayed variably severe clinical signs, including lameness and soft tissue swelling of the limbs proximal to the hoof or in...

The microbiome is essential for extraction of energy and nutrition from plant-based diets and may have facilitated primate adaptation to new dietary niches in response to rapid environmental shifts. Here we use 16S rRNA sequencing to characterize the microbiota of wild western lowland gorillas and sympatric central chimpanzees and demonstrate compo...

The critically endangered population of Far Eastern leopards (Panthera pardus orientalis) may number as few as 60 individuals and is at risk from stochastic processes such as infectious disease. During May 2015, a case of canine distemper virus (CDV) was diagnosed in a wild leopard exhibiting severe neurologic disease in the Russian territory of Pr...

The Bronx River in Bronx, New York spans an area of significant human development and has been subject to historic and ongoing industrial contamination. We evaluated the health of free-ranging native common snapping turtles ( Chelydra serpentina) and nonnative invasive red-eared sliders ( Trachemys scripta) in a segment of the Bronx River between M...

New specimens of the genus Hapalotremus (Theraphosinae) are revised based on the examination of types and additional material collected in Argentina, Bolivia and Peru. A new generic diagnosis is proposed. New information and illustrations are provided for known species and seven new species were recognized and are newly described and illustrated. H...

1. Species monitoring using environmental DNA (eDNA) is a powerful new technique for natural resource scientists and the number of research groups employing eDNA detection is growing rapidly. However, current eDNA sampling technologies consist mainly of do-it-yourself solutions, and the lack of purpose-built sampling equipment is limiting the effic...

Southern River terrapins ( Batagur affinis) are among the most critically endangered turtles in the world. To augment the Cambodia population, a head-start program was established for the endemic subspecies Batagur affinis edwardmolli in 2006, and in 2015, prerelease health assessments were performed on 70 subadults (hatch years, 2006-2011). Combin...

The Blue Iguana (Cyclura lewisi) was brought back from the brink of extinction through in tensive captive breeding and through the protection of areas. While the species has been successfully reintroduced and has been down - listed from Critically Endangered to Endangered, the road to recovery is far from over. Amongst the main threats are deve lop...

Choanal swabs were collected three times at two-week intervals from seventeen asymptomatic captive chelonians, eight Forsten's tortoises (Indotestudo forstenii) and nine Sulawesi forest turtles (Leucocephalon yuwonoi), to document individual Mycoplasma spp. shedding patterns. Four of the Forsten's tortoises and six of the Sulawesi forest turtles te...

Three methods for delivering a live attenuated canine distemper virus (CDV) vaccine to domestic cats ( Felis catus ) were investigated, as models for developing vaccination protocols for tigers ( Panthera tigris ). Twenty domestic cats were randomly divided into four treatment groups: saline injection (negative controls); and oral, intranasal, and...

Avian hemosporidian parasites have been detected in Asia, but little information is known about the hemosporidian parasite lineages that circulate in waterbirds that migrate along the East Asian and Central Asian migratory flyways to breed in Mongolia. To gather baseline data on hemosporidian parasite presence in Mongolian waterbirds, 151 blood-spo...

The 31 May 2013 El Reno, Oklahoma, tornado is used to demonstrate how a video imagery database crowdsourced from storm chasers can be time-corrected and georeferenced to inform severe storm research. The tornado’s exceptional magnitude (∼4.3-km diameter and ∼135 m s−1 winds) and the wealth of observational data highlight this storm as a subject for...

Between 2003 and 2012, 605 southern right whales (SRW; Eubalaena australis) were found dead along the shores of Península Valdés (PV), Argentina. These deaths included alarmingly high annual losses between 2007 and 2012, a peak number of deaths (116) in 2012, and a significant number of deaths across years in calves-of-the-year (544 of 605 [89.9%];...

Batrachochytrium dendrobatidis (Bd), the cause of chytridiomycosis, is a pathogenic fungus that is found worldwide and is a major contributor to amphibian declines and extinctions. We report results of a comprehensive effort to assess the distribution and threat of Bd in one of the Earth's most important biodiversity hotspots, the Albertine Rift in...

Trained model of the current relative habitat suitability and distribution of Bd. A. (Initial model). Current distribution of areas where amphibians are likely to be at risk for Bd infection using original records (maroon hexagons). All areas predicted as suitable where the new positive localities (green hexagons) appear indicate areas where we had...

FASTA file. DNA sequence alignment of partial ITS1-5.8S-ITS2 sequences used in Fig 2. (FASTA)

Calculated copy numbers in positive samples. Log-scale graph showing all Bd-positive samples plotted against the calculated number of copies of the ITS1-5.8S region per swab. Error bars indicate the standard deviation (positive only) for each triplicate sample. Red bars indicate which two samples had corresponding skin tissue analyzed and had histo...

Summary of Bd results from historical specimens. Elevations are in meters above sea level. (DOCX)

PCR results of historical samples collected from Makerere University in Uganda. Elevations are in meters above sea level. (DOCX)

Sample ID, Genus, Date of collection, and GPS location of all Bd positive samples included in the modelling analysis. Elevations are in meters above sea level. (DOCX)

Additional Bd-positive localities provided by Bd-maps.net and E. Greenbaum that went into the modelling analysis [29–32,49]. Elevations are in meters above sea level. (DOCX)

A captive, juvenile, female northern map turtle (Graptemys geographica) was found dead following a brief period of weakness and nasal discharge. Postmortem examination identified pneumonia with necrosis and numerous epithelial, intranuclear viral inclusion bodies, consistent with herpesviral pneumonia. Similar intranuclear inclusions were also asso...

The rich diversity of the world’s reptiles is at risk due to significant population declines of broad taxonomic and geographic scope. Significant factors attributed to these declines include habitat loss, pollution, unsustainable collection and infectious disease. To investigate the presence and significance of a potential pathogen on populations o...

An 18-month-old female spayed ferret was diagnosed with severe anemia secondary to pure red cell aplasia (PRCA). After three months of immunosuppressive therapy for PRCA, the patient presented with anorexia, melena, and jaundice. A biochemical profile showed elevated hepatobiliary enzymes and a marked hyperbilirubinemia suggestive of cholestatic di...

Infectious diseases have caused die-offs in both free-ranging gorillas and chimpanzees. Understanding pathogen diversity and disease ecology is therefore critical for conserving these endangered animals. To determine viral diversity in free-ranging, non-habituated gorillas and chimpanzees in the Republic of Congo, genetic testing was performed on g...

Abstract Mycoplasma infections can cause significant morbidity and mortality in captive and wild chelonians. As part of a health assessment of endangered bog turtles (Glyptemys muhlenbergii) in the northeastern US, choanal and cloacal swabs from these and other sympatric species, including spotted turtles (Clemmys guttata), eastern box turtles (Ter...

Infectious diseases have caused die-offs in both free-ranging gorillas and chimpanzees. Understanding pathogen diversity and disease ecology is therefore critical for conserving these endangered animals. To determine viral diversity in free-ranging, non-habituated gorillas and chimpanzees in the Republic of Congo, genetic testing was performed on g...

Unlabelled: Fewer than 500 Amur tigers (Panthera tigris altaica) remain in the wild. Due to low numbers and their solitary and reclusive nature, tiger sightings across their range in the Russian Far East and China are rare; sightings of sick tigers are rarer still. Serious neurologic disease observed in several wild tigers since 2001 suggested dis...

A female short-beaked common dolphin calf was found stranded in San Diego, California in October 2010, presenting with multifocal ulcerative lesions in the trachea and bronchi. Viral particles suggestive of polyomavirus were detected by EM, and subsequently confirmed by PCR and sequencing. Full genome sequencing (Ion Torrent) revealed a circular ds...

Amphibian trade is known to facilitate the geographic spread of pathogens. Here we assess the health of amphibians traded in Southeast Asia for food or as pets, focusing on Batrachochytrium dendrobatidis (Bd), ranavirus and general clinical condition. Samples were collected from 2,389 individual animals at 51 sites in Lao PDR, Cambodia, Vietnam and...

The global trade in wildlife has historically contributed to the emergence and spread of infectious diseases. The United States is the world's largest importer of wildlife and wildlife products, yet minimal pathogen surveillance has precluded assessment of the health risks posed by this practice. This report details the findings of a pilot project...

The mountain peacock pheasant (Polyplectron inopinatum), the Malayan peacock pheasant (Polyplectron malacense), and the Congo peafowl (Afropavo congensis) are all listed as vulnerable to extinction under the International Union for Conservation of Nature Red List of Threatened Species. Here the authors report fatal infection with a novel herpesviru...

The ARV1-encoded protein mediates sterol transport from the endoplasmic reticulum (ER) to the plasma membrane. Yeast ARV1 mutants accumulate multiple lipids in the ER and are sensitive to pharmacological modulators of both sterol and sphingolipid metabolism. Using fluorescent and electron microscopy, we demonstrate sterol accumulation, subcellular...

Macrophage apoptosis in advanced atheromata, a key process in plaque necrosis, involves the combination of ER stress with other proapoptotic stimuli. We show here that oxidized phospholipids, oxidized LDL, saturated fatty acids (SFAs), and lipoprotein(a) trigger apoptosis in ER-stressed macrophages through a mechanism requiring both CD36 and Toll-l...

Background: The endoplasmic reticulum (ER) stress pathway known as the Unfolded Protein Response (UPR) is an adaptive survival pathway that protects cells from the buildup of misfolded proteins, but under certain circumstances it can lead to apoptosis. ER stress has been causally associated with macrophage apoptosis in advanced atherosclerosis of...

Antiatherogenic effects of plasma high-density lipoprotein (HDL) include the ability to inhibit apoptosis of macrophage foam cells. The ATP-binding cassette transporters ABCA1 and ABCG1 have a major role in promoting cholesterol efflux from macrophages to apolipoprotein A-1 and HDL and are upregulated during the phagocytosis of apoptotic cells (eff...

Proper sterol distribution within the cell is a critical component of membrane homeostasis. The endoplasmic reticulum (ER)‐localized protein Arvl mediates sterol transport from the ER to the plasma membrane. Alterations in ER sterol distribution are a stimulus for unfolded protein response (UPR) activation. We hypothesize that the loss of Arv1p in...

ER stress-induced apoptosis is implicated in various pathological conditions, but the mechanisms linking ER stress-mediated signaling to downstream apoptotic pathways remain unclear. Using human and mouse cell culture and in vivo mouse models of ER stress-induced apoptosis, we have shown that cytosolic calcium resulting from ER stress induces expre...

Plaque necrosis in advanced atheromata, which triggers acute atherothrombotic vascular events, is caused by the apoptosis of lesional macrophages coupled with defective phagocytic clearance of the dead cells. The central enabling event in macrophage apoptosis relevant to advanced atherosclerosis is the unfolded protein response (UPR), an endoplasmi...

Endoplasmic reticulum (ER) stress is a hallmark of advanced atherosclerosis, but its causative role in plaque progression is unknown. In vitro studies have implicated the ER stress effector CHOP in macrophage apoptosis, a process involved in plaque necrosis in advanced atheromata. To test the effect of CHOP deficiency in vivo, aortic root lesions o...

ER stress occurs in macrophage-rich areas of advanced atherosclerotic lesions and contributes to macrophage apoptosis and subsequent plaque necrosis. Therefore, signaling pathways that alter ER stress-induced apoptosis may affect advanced atherosclerosis. Here we placed Apoe-/- mice deficient in macrophage p38alpha MAPK on a Western diet and found...

The molecular events linking lipid accumulation in atherosclerotic plaques to complications such as aneurysm formation and plaque disruption are poorly understood. BALB/c-Apoe(-/-) mice bearing a null mutation in the Npc1 gene display prominent medial erosion and atherothrombosis, whereas their macrophages accumulate free cholesterol in late endoso...