Robert N Fisher
Dr. Robert Fisher is a conservation biologist with the U.S. 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.
RESEARCH INTERESTS
- Conservation biology
- Biogeography
- Modelling
- Natural history
- Speciation
- Invasive species
- Climate variability
- Anthropocene
Education and Certifications
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
Science and Products
Evolutionary hotspots in the Mojave Desert
Mapping behavioral landscapes for animal movement: a finite mixture modeling approach
Three new species of Coccidia (Apicomplexa: Eimeriidae) from Skinks, Lipinia spp. (Sauria: Scincidae), from Oceania
Joint estimation of habitat dynamics and species interactions: Disturbance reduces co-occurrence of non-native predators with an endangered toad
Urban habitat fragmentation and genetic population structure of bobcats in coastal southern California
Effects of spatial subsidies and habitat structure on the foraging ecology and size of geckos
Cryptic extinction of a common Pacific lizard Emoia impar (Squamata, Scincidae) from the Hawaiian Islands.
Three pathogens in sympatric populations of pumas, bobcats, and domestic cats: Implications for infections disease transmission
A preliminary assessment of the Nactus pelagicus species group (Squamata: Gekkonidae) in New Guinea and a new species from the Admiralty Islands
Report on the reptiles of Upland Savai’i
Refugial isolation and divergence in the Narrowheaded Gartersnake species complex (Thamnophis rufipunctatus) as revealed by multilocus DNA sequence data
Effects of large-scale wildfire on ground foraging ants (Hymenoptera: Formicidae) in southern California
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Evolutionary hotspots in the Mojave Desert
Genetic diversity within species provides the raw material for adaptation and evolution. Just as regions of high species diversity are conservation targets, identifying regions containing high genetic diversity and divergence within and among populations may be important to protect future evolutionary potential. When multiple co-distributed species show spatial overlap in high genetic diversity anAuthorsAmy G. Vandergast, Richard D. Inman, Kelly R. Barr, Kenneth E. Nussear, Todd C. Esque, Stacie A. Hathaway, Dustin A. Wood, Philip A. Medica, Jesse W. Breinholt, Catherine L. Stephen, Andrew D. Gottscho, Sharyn B. Marks, W. Bryan Jennings, Robert N. FisherMapping behavioral landscapes for animal movement: a finite mixture modeling approach
Because of its role in many ecological processes, movement of animals in response to landscape features is an important subject in ecology and conservation biology. In this paper, we develop models of animal movement in relation to objects or fields in a landscape. We take a finite mixture modeling approach in which the component densities are conceptually related to different choices for movementAuthorsJeff A. Tracey, Jun Zhu, Erin E. Boydston, Lisa M. Lyren, Robert N. Fisher, Kevin R. CrooksThree new species of Coccidia (Apicomplexa: Eimeriidae) from Skinks, Lipinia spp. (Sauria: Scincidae), from Oceania
Between September 1991 and March 1993, 25 moth skinks (Lipinia noctua) were collected from various localities on the Cook Islands, Fiji, Papua New Guinea (PNG), and Vanuatu and examined for coccidians. In addition, a single Roux's lipinia skink (Lipinia rouxi) was collected from PNG and examined for coccidia. Sixteen (64%) L. noctua were found to harbor 2 new eimerians, and L. rouxi harbored anothAuthorsChris T. McAllister, Donald W. Duszynski, Christopher C. Austin, Robert N. FisherJoint estimation of habitat dynamics and species interactions: Disturbance reduces co-occurrence of non-native predators with an endangered toad
1. Ecologists have long been interested in the processes that determine patterns of species occurrence and co-occurrence. Potential short-comings of many existing empirical approaches that address these questions include a reliance on patterns of occurrence at a single time point, failure to account properly for imperfect detection and treating the environment as a static variable.2. We fit detectAuthorsDavid A.W. Miller, Cheryl S. Brehme, James E. Hines, James D. Nichols, Robert N. FisherUrban habitat fragmentation and genetic population structure of bobcats in coastal southern California
Although habitat fragmentation is recognized as a primary threat to biodiversity, the effects of urban development on genetic population structure vary among species and landscapes and are not yet well understood. Here we use non-invasive genetic sampling to compare the effects of fragmentation by major roads and urban development on levels of dispersal, genetic diversity, and relatedness betweenAuthorsE.W. Ruell, S.P.D. Riley, M.R. Douglas, M.F. Antolin, J.R. Pollinger, J.A. Tracey, L.M. Lyren, E. E. Boydston, Robert N. Fisher, K.R. CrooksEffects of spatial subsidies and habitat structure on the foraging ecology and size of geckos
While it is well established that ecosystem subsidies—the addition of energy, nutrients, or materials across ecosystem boundaries—can affect consumer abundance, there is less information available on how subsidy levels may affect consumer diet, body condition, trophic position, and resource partitioning among consumer species. There is also little information on whether changes in vegetation strucAuthorsAmy A. Briggs, Hillary S. Young, Douglas J. McCauley, Stacie A. Hathaway, Rodolfo Dirzo, Robert N. FisherCryptic extinction of a common Pacific lizard Emoia impar (Squamata, Scincidae) from the Hawaiian Islands.
Most documented declines of tropical reptiles are of dramatic or enigmatic species. Declines of widespread species tend to be cryptic. The early (1900s) decline and extinction of the common Pacific skink Emoia impar from the Hawaiian Islands is documented here through an assessment of literature, museum vouchers and recent fieldwork. This decline appears contemporaneous with the documented declineAuthorsRobert Fisher, Ivan IneichThree pathogens in sympatric populations of pumas, bobcats, and domestic cats: Implications for infections disease transmission
Anthropogenic landscape change can lead to increased opportunities for pathogen transmission between domestic and non-domestic animals. Pumas, bobcats, and domestic cats are sympatric in many areas of North America and share many of the same pathogens, some of which are zoonotic. We analyzed bobcat, puma, and feral domestic cat samples collected from targeted geographic areas. We examined exposureAuthorsSarah N. Bevins, Scott Carver, Erin E. Boydston, Lisa M. Lyren, Mat Alldredge, Kenneth A. Logan, Seth P.D. Riley, Robert N. Fisher, T. Winston Vickers, Walter Boyce, Mo Salman, Michael R. Lappin, Kevin R. Crooks, Sue VandeWoudeA preliminary assessment of the Nactus pelagicus species group (Squamata: Gekkonidae) in New Guinea and a new species from the Admiralty Islands
The Slender-toed Geckos (Nactus) currently have four recognized species in New Guinea, and these species divide into two sister clades: a pelagicus clade and a vankampeni clade (Heinicke et al. 2010). The latter contains three dwarf species. The former consists of five bisexual populations, of which numerous New Guinea populations are uncharacterized nomenclaturally and lumped under the epithet ‘pAuthorsGeorge R. Zug, Robert N. FisherReport on the reptiles of Upland Savai’i
The reptile team conducted a 21 kilometre transect from the coast east of Asau to the uplands ending near Mauga Silisili at over 1720 m elevation. This transect covered the main habitats on Savai’i and allowed the team to determine where various reptile species and invasive species occurred across this elevational gradient. No previous reptile research had taken place on Savai’i above the elevatioAuthorsRobert N. Fisher, Moeumu UiliRefugial isolation and divergence in the Narrowheaded Gartersnake species complex (Thamnophis rufipunctatus) as revealed by multilocus DNA sequence data
Glacial–interglacial cycles of the Pleistocene are hypothesized as one of the foremost contributors to biological diversification. This is especially true for cold‐adapted montane species, where range shifts have had a pronounced effect on population‐level divergence. Gartersnakes of the Thamnophis rufipunctatus species complex are restricted to cold headwater streams in the highlands of the SierrAuthorsDustin A. Wood, A. G. Vandergast, A. Lemos Espinal, Robert N. Fisher, A.T. HolycrossEffects of large-scale wildfire on ground foraging ants (Hymenoptera: Formicidae) in southern California
We investigated the effect of broad-scale wildfire on ground foraging ants within southern California. In October and November of 2003, two wildfires burned large portions of the wildlands within San Diego County. Between January 2005 and September 2006, we surveyed 63 plots across four sites to measure the effect of the fires on the ant assemblages present in four vegetation types: 1) coastal sagAuthorsTritia Matsuda, Greta Turschak, Cheryl Brehme, Carlton Rochester, Milan Mitrovich, Robert Fisher - News
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