Robert N Fisher
Biography
Dr. Robert Fisher is a conservation biologist with the US Geological Survey’s Western Ecological Research Center and works as part of a large integrated team. His focus has been on how natural systems are responding to the Anthropocene, and what types of resiliency they have or lack as it relates to maintaining ecological integrity and biodiversity. Additionally, through understanding individual species and community responses to perturbations through modern monitoring techniques, he and his team can determine appropriate management experiments or options to possibly recover resiliency. Geographically they have two foci, the first is southern California where urbanization and conservation planning bring various direct and indirect drivers of ecological change, and climate variability is currently extreme and drives landscape level drought and wildfires. Their second foci are the tropical islands of the Pacific Basin, from Palau and Papua New Guinea east to Hawai’i. These islands have also been driven by human change and are on the front line as extreme recent weather variability in the cyclone belt impact terrestrial ecosystems. Understanding how biodiversity was generated in this ecoregion is critical to managing its loss, and their team focuses across time and space (biogeography) to understand these processes utilizing molecular tools tied to expeditions of discovery in this poorly studied ecoregion.
EDUCATION
- Ph.D., Population Biology, University of California, Davis, CA 1995
- M.S., Zoology, University of California, Davis, CA 1991
- B.S., Biology, University of California, Irvine, CA 1988
RESEARCH INTERESTS
- Conservation biology
- Biogeography
- Modelling
- Natural history
- Speciation
- Invasive species
- Climate variability
- Anthropocene
Science and Products
The Introduced Argentine ant (Linepithema humile) on the California Channel Islands: Distribution and Patterns of Spread
The Argentine ant (Linepithema humile) is a widespread and abundant introduced species that disrupts ecosystems throughout its introduced range. This invader was inadvertently introduced to Santa Catalina, San Clemente, Santa Cruz, and San Nicolas Islands at various points during the past century but currently appears to be absent from the...
Boser, Christina L.; Merrell, Korie; Fisher, Robert N.; Naughton, Ida; Holway, David A Multi-scale effects of land cover and urbanization on the habitat suitability of an endangered toad
Habitat degradation, entwined with land cover change, is a major driver of biodiversity loss. Effects of land cover change on species can be direct (when habitat is converted to alternative land cover types) or indirect (when land outside of the species habitat is altered). Hydrologic and ecological connections between terrestrial and...
Treglia, Michael L.; Landon, Adam C; Fisher, Robert N.; Kyle, Gerard; Fitzgerald, Lee A. Identifying management-relevant research priorities for responding to disease-associated amphibian declines
A research priority can be defined as a knowledge gap that, if resolved, identifies the optimal course of conservation action. We (a group of geographically distributed and multidisciplinary research scientists) used tools from nominal group theory and decision analysis to collaboratively identify and prioritize information...
Campbell Grant, Evan H.; Adams, M.J.; Fisher, Robert N.; Grear, Daniel A.; Halstead, Brian J.; Hossack, Blake R.; Muths, Erin L.; Richgels, Katherine L. D.; Russell, Robin E.; Smalling, Kelly L.; Waddle, J. Hardin; Walls, Susan C.; White, C. LeAnn Quantifying climate sensitivity and climate-driven change in North American amphibian communities
Changing climate will impact species’ ranges only when environmental variability directly impacts the demography of local populations. However, measurement of demographic responses to climate change has largely been limited to single species and locations. Here we show that amphibian communities are responsive to climatic variability, using >...
Miller, David A.W.; Campbell Grant, Evan H.; Muths, Erin L.; Amburgey, Staci M.; Adams, M.J.; Joseph, Maxwell B.; Waddle, J. Hardin; Johnson, Pieter T.J.; Ryan, Maureen E.; Schmidt, Benedikt R.; Calhoun, Daniel L.; Davis, Courtney L.; Fisher, Robert N.; Green, David M.; Hossack, Blake R.; Rittenhouse, Tracy A.G.; Walls, Susan C.; Bailey, Larissa L.; Cruickshank, Sam S.; Fellers, Gary M.; Gorman, Thomas A.; Haas, Carola A.; Hughson, Ward; Pilliod, David S.; Price, Steven J.; Ray, Andrew M.; Sadinski, Walter; Saenz, Daniel; Barichivich, William J.; Brand, Adrianne B.; Brehme, Cheryl S.; Dagit, Rosi; Delaney, Katy S.; Glorioso, Brad M.; Kats, Lee B.; Kleeman, Patrick M.; Pearl, Christopher; Rochester, Carlton J.; Riley, Seth P. D.; Roth, Mark F.; Sigafus, Brent Prioritizing conserved areas threatened by wildfire and fragmentation for monitoring and management
In many parts of the world, the combined effects of habitat fragmentation and altered disturbance regimes pose a significant threat to biodiversity. This is particularly true in Mediterranean-type ecosystems (MTEs), which tend to be fire-prone, species rich, and heavily impacted by human land use. Given the spatial complexity of overlapping...
Tracey, Jeff A.; Rochester, Carlton J.; Hathaway, Stacie A.; Preston, Kristine L.; Syphard, Alexandra D.; Vandergast, Amy G.; Diffendorfer, James E.; Franklin, Janet; MacKenzie, Jason B.; Oberbauer, Tomas A.; Tremor, Scott; Winchell, Clark S.; Fisher, Robert N. Effects of urbanization, and habitat composition on site occupancy of two snake species using regional monitoring data from southern California
Detection data from a regional, reptile-monitoring program conducted by the U.S. Geological Survey were analyzed to understand the effects of urbanization and habitat composition on site occupancy of the coachwhip (Masticophis flagellum) and striped racer (M. lateralis) in coastal southern California. Likelihood-based occupancy models indicated...
Mitrovich, Milan J.; Diffendorfer, James E.; Brehme, Cheryl S.; Fisher, Robert N. All is not lost: Herpetofaunal “extinctions” in the Fiji Islands
Invasive mammals are implicated in the decline or extinction of numerous insular vertebrate species worldwide, yet rediscoveries of supposedly extinct vertebrates occur regularly. In particular, recent records of secretive amphibian and reptile taxa in the Fiji Islands show that earlier claimed extirpations of Fijian wildlife were erroneous. We...
Clause, Adam G.; Thomas-Moko, Nunia; Rasalato, Sialisi; Fisher, Robert N. Insular biogeographic origins and high phylogenetic distinctiveness for a recently depleted lizard fauna from Christmas Island, Australia
Striking faunal turnover across Asia and Australasia, most famously along the eastern edge of the Sunda Shelf or ‘Wallace's Line’, has been a focus of biogeographic research for over 150 years. Here, we investigate the origins of a highly threatened endemic lizard fauna (four species) on Christmas Island. Despite occurring less 350 km south of the...
Oliver, Paul M.; Blom, Mozes P. K.; Cogger, Harold G.; Fisher, Robert N.; Richmond, Jonathan Q.; Woinarski, John C. Z. An objective road risk assessment method for multiple species: ranking 166 reptiles and amphibians in California
ContextTransportation and wildlife agencies may consider the need for barrier structures and safe wildlife road-crossings to maintain the long-term viability of wildlife populations. In order to prioritize these efforts, it is important to identify species that are most at risk of extirpation from road-related impacts.PurposeOur goal was to...
Brehme, Cheryl S.; Hathaway, Stacie A.; Fisher, Robert N. Longevity and population age structure of the arroyo southwestern toad (Anaxyrus californicus) with drought implications
The arroyo southwestern toad is a specialized and federally endangered amphibian endemic to the coastal plains and mountains of central and southern California and northwestern Baja California. It is largely unknown how long these toads live in natural systems, how their population demographics vary across occupied drainages, and how hydrology...
Fisher, Robert N.; Brehme, Cheryl S.; Hathaway, Stacie A.; Hovey, Tim E.; Warburton, Manna L.; Stokes, Drew C.
Golden eagle (Aquila chrysaetos) habitat selection as a function of land use and terrain, San Diego County, California
Beginning in 2014, the U.S. Geological Survey, in collaboration with Bloom Biological, Inc., began telemetry research on golden eagles (Aquila chrysaetos) captured in the San Diego, Orange, and western Riverside Counties of southern California. This work was supported by the San Diego Association of Governments, California Department of Fish and...
Tracey, Jeff A.; Madden, Melanie C.; Bloom, Peter H.; Katzner, Todd E.; Fisher, Robert N. Occurrence of Batrachochytrium dendrobatidis in anurans of the Mediterranean region of Baja California, México
Chytridiomycosis is caused by the fungal pathogen Batrachochytrium dendrobatidis (Bd) and is regarded as one of the most significant threats to global amphibian populations. In México, Bd was first reported in 2003 and has now been documented in 13 states. We visited 33 localities and swabbed 199 wild-caught anurans from 7 species (5 native...
Peralta-Garcia, Anny; Adams, Andrea J.; Briggs, Cheryl J.; Galina-Tessaro, Patricia; Valdez-Villavicencio, Jorge H.; Hollingsworth, Bradford; Shaffer, H. Bradley; Fisher, Robert N.