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
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. 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. 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. At the end of the line: independent overwater colonizations of the Solomon Islands by a hyperdiverse trans-Wallacean lizard lineage (Cyrtodactylus: Gekkota: Squamata)
The islands of East Melanesia have generated key insights into speciation processes and community assembly. However, when and how these islands began to form, emerge and accumulate endemic taxa remains poorly understood. Here, we show that two divergent lineages within the world’s most diverse genus of geckos (Cyrtodactylus) occur in the Solomon...
Oliver, Paul M.; Travers, Scott L; Richmond, Jonathan Q.; Pikacha, Patrick; Fisher, Robert N. Heterogeneous responses of temperate-zone amphibian populations to climate change complicates conservation planning
The pervasive and unabated nature of global amphibian declines suggests common demographic responses to a given driver, and quantification of major drivers and responses could inform broad-scale conservation actions. We explored the influence of climate on demographic parameters (i.e., changes in the probabilities of survival and recruitment)...
Muths, Erin L.; Chambert, Thierry A.; Schmidt, B. R.; Miller, D. A. W.; Hossack, Blake R.; Joly, P.; Grolet, O.; Green, D. M.; Pilliod, David S.; Cheylan, M.; Fisher, Robert N.; McCaffery, R. M.; Adams, M. J.; Palen, W. J.; Arntzen, J. W.; Garwood, J.; Fellers, Gary M.; Thirion, J. M.; Grant, Evan H. Campbell; Besnard, A. Candoia Bibroni (Pacific Boa). Diet
No abstract available.
Clause, Adam G.; Fraser, Mark J.; Pene, Sarah; Thomas-Moko, Nunia; Fisher, Robert N.