Abstract Habitat disturbance from development, resource extraction, off‐road vehicle use, and energy development ranks highly among threats to desert systems worldwide. In the Mojave Desert, United States, these disturbances have promoted establishment of nonnative plants, so that native grasses forbs are now intermixed with, or been replaced by invasive, Mediterranean grasses. This shift in plant composition has altered food availability for Desert tortoises ( Gopherus agassizii ), a...

Migrating adult Pacific salmon (Oncorhynchus spp.) are sensitive to warm water (>18 °C), with a range of consequences from decreased spawning success early mortality. We examined the proportion Yukon River Chinook (O. tshawytscha) exhibiting evidence heat stress assess potential that high temperatures contribute freshwater mortality in northern population. Water greater than 18 °C have occurred almost annually and correspond low population abundance since 1990s. Using gene transcription...

ABSTRACT Chinook salmon (Oncorhynchus tshawytscha) declines are widespread and may be attributed, at least in part, to warming river temperatures. Water temperatures the Yukon River tributaries often exceed 18°C, a threshold commonly associated with heat stress elevated mortality Pacific salmon. Untangling complex web of direct indirect physiological effects on is difficult natural setting innumerable system challenges but necessary increase our understanding both lethal sublethal impacts...

Abstract Increasing risk of pathogen spillover coupled with overall declines in wildlife population abundance the Anthropocene make infectious disease a relevant concern for species conservation worldwide. While emerging molecular tools could improve our diagnostic capabilities and give insight into mechanisms underlying risk, they have rarely been applied practice. Here, employing previously reported gene transcription panel common immune markers to track physiological changes, we present...

Abstract The loss of tidal wetlands in the San Francisco Bay estuary have led to declines native fish presence. Restoration this area has intensified, with a primary goal increasing number fishes. We compared presence longfin smelt naturally accreted and beneficial dredge reuse as measure successful restoration. used environmental DNA (eDNA) analyses our metric for community composition, employing two different water sampling methods comparison (standard high‐volume). Longfin were present...

First posted September 28, 2017 For additional information, contact: Director, Western Ecological Research Center U.S. Geological Survey 3020 State University Drive East Sacramento, California 95819 Detecting populations of rare or cryptic species is essential for their conservation. like giant gartersnakes (Thamnophis gigas), conventional survey methods can be expensive and inefficient. These sampling difficulties might overcome by modern techniques that detect deoxyribonucleic acid (DNA)...

Abstract Immune function plays an important role in animal's defense against infectious disease. In reptiles, immune responses may be complex and counterintuitive, diagnostic tools used to identify infection, such as induced antibody are limited. Recent studies using gene transcription profiling tortoises have proven useful identifying various intrinsic extrinsic stressors. As part of a larger experiment with Mojave desert ( Gopherus agassizii ), we facilitated the transmission pathogenic...

The analysis of blood constituents is a widely used tool to aid in monitoring animal health and disease. However, classic diagnostics (i.e. hematologic plasma biochemical values) often do not provide sufficient information determine the state an animal's health. Field studies on wild tortoises other reptiles have had limited success drawing significant inferences between physiological immunological condition. recent research using gene transcription profiling threatened Mojave desert...

Abstract Manipulative experiments provide stronger evidence for identifying cause-and-effect relationships than correlative studies, but protocols implementing temperature manipulations are lacking large species in remote settings. We developed an experimental protocol holding adult Chinook salmon (Oncorhynchus tshawytscha) and exposing them to elevated treatments. The goal of the was validate heat stress biomarkers by increasing river water from ambient (~14°C) a treatment 18°C or 21°C then...

The 1989 Exxon Valdez oil spill damaged a wide range of natural resources, including intertidal communities, and post-spill studies demonstrated acute chronic exposure injury to an array species. Standard toxicological methods evaluate petroleum contaminants have assessed tissue burdens, with fewer assays providing indicators health or physiology, particularly when contaminant levels are low chronic. Marine mussels ubiquitous crucial component the nearshore environment, new genomic...

Using a panel of genes stimulated by oil exposure in laboratory study, we evaluated gene transcription blood leukocytes sampled from sea otters captured 2006–2012 western Prince William Sound (WPWS), Alaska, 17–23 years after the 1989 Exxon Valdez spill (EVOS). We compared WPWS to reference populations (not affected EVOS) Alaska Peninsula (2009), Katmai National Park and Preserve Clam Lagoon at Adak Island (2012), Kodiak (2005) captive aquaria. Statistically, otter transcript profiles...

Abstract In February 2019, five individuals with Salmonella Enteritidis infections matching by whole genome sequencing (WGS) were identified in the province of British Columbia (BC), Canada. Individuals available exposure information all reported unique to reptiles or rodents, prompting an outbreak investigation. We describe how WGS, case interviews, traceback and environmental testing used link this one supplier live mice primarily as feeder rodents for pet snakes. Our investigation...

Rapid and accelerating warming of salmon habitat has the potential to lower productivity Pacific (Oncorhynchus species) populations. Heat stress biomarkers can indicate where is most likely affecting fish populations; however, we often lack clear classifications that separate individuals with without heat needed make these tools operational. We conducted a exposure experiment trials lasting 12 or 36 h using juvenile Chinook tshawytscha) coho kisutch) validate in white muscle. Following...

ABSTRACT Respiratory disease is a key factor affecting the conservation and recovery of bighorn sheep ( Ovis canadensis ) populations. Innovative, minimally invasive tools such as gene transcription–based diagnostics have potential to improve our understanding broad range factors that can affect health wild sheep. Evaluation transcript levels for genes representative multiple internal systems enables measurement physiological responses individuals well populations environmental stressors...

With rapidly changing marine ecosystems, shifts in abundance and distribution are being documented for a variety of intertidal species. We examined two adjacent populations Pacific razor clams (Siliqua patula) lower Cook Inlet, Alaska. One population (east) supported sport personal use fishery, but this has been closed since 2015 due to declines abundance, the second (west) continues support commercial fisheries. used gene expression investigate potential causes east side decline, comparing...


 Climate change brings about novel types of public health emergencies. Unforeseen challenges put additional pressure on systems and require innovative approaches to address emerging needs. The Indigenous Peoples is particularly impacted by the changing climate, because their close connection land. For instance, physical, emotional, mental, spiritual well-being coastal First Nations in British Columbia (BC), Canada, interconnected with abundance healthy marine food sources that form...

Health diagnostics of wildlife have historically relied on the evaluation select serum biomarkers and identification a contaminant or pathogen burden within specific tissues as an indicator level insult. However, these approaches fail to measure physiological reaction individual stressors, thus limiting scope interpretation. Gene-based health provide opportunity for alternate, whole-system, holistic assessment health, not only in individuals populations but potentially ecosystems. Seabirds...

An opportunistic investigation into ecosystem instability in Kachemak Bay (KBay), Alaska, has led us to investigate exposure toxic algae sea otters. We used gene expression explore the physiological health of otters sampled KBay May 2019. found altered levels transcripts comparison with reference from clinically normal, oil-exposed, and nutritionally challenged populations over past decade. were markedly divergent other groups for five genes, which indicated involvement neurological,...