Western Ecological Research Center
Foraging and fasting can influence contaminant concentrations in animals: an example with mercury contamination in a free-ranging marine mammal
Large fluctuations in animal body mass in relation to life-history events can influence contaminant concentrations and toxicological risk. We quantified mercury concentrations in adult northern elephant seals (Mirounga angustirostris) before and after lengthy at sea foraging trips (n = 89) or fasting periods on land (n = 27), and showed that...Peterson, Sarah; Ackerman, Joshua T.; Crocker, Daniel E.; Costa, Daniel P.
To reduce the global burden of human schistosomiasis, use ‘old fashioned’ snail control
Control strategies to reduce human schistosomiasis have evolved from ‘snail picking’ campaigns, a century ago, to modern wide-scale human treatment campaigns, or preventive chemotherapy. Unfortunately, despite the rise in preventive chemotherapy campaigns, just as many people suffer from schistosomiasis today as they did 50 years ago. Snail...Sokolow, Susanne H.; Wood, Chelsea L.; Jones, Isabel J.; Lafferty, Kevin D.; Kuris, Armand; Hsieh, Michael H.; De Leo, Giulio A.
MHC class II DRB diversity predicts antigen recognition and is associated with disease severity in California sea lions naturally infected with Leptospira interrogans
We examined the associations between California sea lion MHC class II DRB (Zaca-DRB) configuration and diversity, and leptospirosis. As Zaca-DRB gene sequences are involved with antigen presentation of bacteria and other extracellular pathogens, we predicted that they would play a role in determining responses to these pathogenic spirochaetes....Acevedo-Whitehouse, Karina; Gulland, Frances; Bowen, Lizabeth
Human presence diminishes the importance of climate in driving fire activity across the United States
Growing human and ecological costs due to increasing wildfire are an urgent concern in policy and management, particularly given projections of worsening fire conditions under climate change. Thus, understanding the relationship between climatic variation and fire activity is a critically important scientific question. Different factors limit fire...Syphard, Alexandra D.; Keeley, Jon E.; Pfaff, Anne Hopkins; Ferschweiler, Ken
Ecosystem features determine seagrass community response to sea otter foraging
Comparing sea otter recovery in California (CA) and British Columbia (BC) reveals key ecosystem properties that shape top-down effects in seagrass communities. We review potential ecosystem drivers of sea otter foraging in CA and BC seagrass beds, including the role of coastline complexity and environmental stress on sea otter effects. In BC, we...Hessing-Lewis, Margot; Rechsteiner, Erin U.; Hughes, Brent B.; Tinker, M. Tim; Monteith, Zachary L.; Olson, Angeleen M.; Henderson, Matthew Morgan; Watson, Jane C.
Landscape-scale variation in canopy water content of giant sequoias during drought
Recent drought (2012–2016) caused unprecedented foliage dieback in giant sequoias (Sequoiadendron giganteum), a species endemic to the western slope of the southern Sierra Nevada in central California. As part of an effort to understand and map sequoia response to droughts, we studied the patterns of remotely sensed canopy water content (CWC),...Paz-Kagan, Tarin; Vaughn, Nicolas R.; Martin, Roberta E.; Brodrick, Philip G.; Stephenson, Nathan L.; Das, Adrian; Nydick, Koren R.; Asner, Gregory P.
Navigating translational ecology: Creating opportunities for scientist participation
Interest in translational ecology (TE) – a research approach that yields useful scientific outcomes through ongoing collaboration between scientists and stakeholders – is growing among both of these groups. Translational ecology brings together participants from different cultures and with different professional incentives. We address ways to...Hallett, Lauren M.; Morelli, Toni; Gerber, Leah R.; Moritz, Max A.; Schwartz, Mark W.; Stephenson, Nathan L.; Tank, Jennifer L.; Williamson, Matthew A.; Woodhouse, Connie A.
Oak habitat recovery on California's largest islands: Scenarios for the role of corvid seed dispersal
Seed dispersal by birds is central to the passive restoration of many tree communities. Reintroduction of extinct seed dispersers can therefore restore degraded forests and woodlands. To test this, we constructed a spatially explicit simulation model, parameterized with field data, to consider the effect of different seed dispersal scenarios on...Pesendorfer, Mario B.; Baker, Christopher M.; Stringer, Martin; McDonald-Madden, Eve; Bode, Michael; McEachern, A. Kathryn; Morrison, Scott A.; Sillett, T. Scott
Using gene transcription to assess ecological and anthropological stressors in brown bears
Increasingly, population- and ecosystem-level health assessments are performed using sophisticated molecular tools. Advances in molecular technology enable the identification of synergistic effects of multiple stressors on the individual physiology of different species. Brown bears (Ursus arctos) are an apex predator; thus, they are ideal...Bowen, Lizabeth; Miles, A. Keith; Waters, Shannon C.; Gustine, Dave; Joly, Kyle; Hilderbrand, Grant
Loss of dendritic connectivity in southern California's urban riverscape facilitates decline of an endemic freshwater fish
Life history adaptations and spatial configuration of metapopulation networks allow certain species to persist in extreme fluctuating environments, yet long-term stability within these systems relies on the maintenance of linkage habitat. Degradation of such linkages in urban riverscapes can disrupt this dynamic in aquatic species, leading to...Richmond, Jonathan Q.; Backlin, Adam R.; Galst-Cavalcante, Carey; O'Brien, John W.; Fisher, Robert N.
Characters in Arctostaphylos taxonomy
There is value in understanding the past and how it has affected the present. Science focuses on empirical findings, and we know that our prior experiences and those of our predecessors play important roles in determining how we interpret the present. We learn from accomplishments and foibles of predecessors and appreciate the real life...Keeley, Jon E.; Parker, V. Thomas; Vasey, Michael C.
An extirpated lineage of a threatened frog species resurfaces in southern California
Southern California has experienced widespread amphibian declines since the 1960s. One species, the Vulnerable California red-legged frog Rana draytonii, is now considered to be extirpated from most of southern California. In February 2017 a population of R. draytonii was discovered in the southern foothills of the San Bernardino...Backlin, Adam R.; Richmond, Jonathan Q.; Gallegos, Elizabeth; Christensen, Clinton K.; Fisher, Robert N.