A5089588577- Fish Ecology and Management Studies
- Aquatic Invertebrate Ecology and Behavior
- Hydrology and Sediment Transport Processes
- Hydrology and Watershed Management Studies
- Fish Biology and Ecology Studies
- Crustacean biology and ecology
- Marine and fisheries research
- Mercury impact and mitigation studies
- Parasite Biology and Host Interactions
- Wildlife Ecology and Conservation
- Isotope Analysis in Ecology
- Environmental Toxicology and Ecotoxicology
- Genetic diversity and population structure
- Genetic and phenotypic traits in livestock
- Helminth infection and control
- Environmental Justice and Health Disparities
- Toxic Organic Pollutants Impact
- Amphibian and Reptile Biology
- Ecology and biodiversity studies
- Microbial bioremediation and biosurfactants
- Bird parasitology and diseases
- Mollusks and Parasites Studies
- Myxozoan Parasites in Aquatic Species
- Fish biology, ecology, and behavior
- Freshwater macroinvertebrate diversity and ecology
Arizona Game and Fish Department
2016-2025
Texas Tech University
2008-2023
University of Arizona
2013
Queen's University Belfast
2009
Illinois Archaeological Survey
2005-2008
Holloman Air Force Base
2006
North Dakota State University
2005-2006
Dakota State University
2005
Washington State Department of Ecology
2005
ABSTRACT Objective Habitat fragmentation is common in riverine systems worldwide, and often thought of a negative context. However, some barriers may create refugia for native species by excluding nonnative species. In the Colorado River, USA, recession Lake Mead subsequent river superimposition resulted formation Pearce Ferry Rapid, formidable hydraulic feature that prevent fish from accessing habitat western Grand Canyon. Here, we analyzed communties above below rapid used remote sending...
Summary 1. Managing populations of predators and their prey to achieve conservation or resource management goals is usually technically challenging frequently socially controversial. This true even in the simplest ecosystems but can be made much worse when predator–prey relationships are influenced by complex interactions, such as biological invasions, population trends animal movements. 2. Lough Neagh Northern Ireland a European stronghold for pollan Coregonus autumnalis , coregonine fish...
Spawning phenology and associated migrations of fishes are often regulated by factors such as temperature stream discharge, but flow regulation mainstem rivers coupled with climate change might disrupt these cues affect fitness. Flannelmouth sucker (Catostomus latipinnis) persisting in heavily modified river networks known to spawn tributaries that provide better spawning habitat than neighboring subject degradation (e.g., embedded sediments, altered thermal regimes, disconnected...
Abstract Habitat descriptions found in critical habitat designations and recovery plans are important for protecting endangered species. However, order to protect habitat, it is necessary update of use when range shifts occur or new studies change the understanding use. This study examined a threatened desert fish determine whether current matched documents. Recovery documents describe humpback chub ( Gila cypha ) as being dependent on rocky, canyon‐bound habitats during all life stages, but...
Abstract – Habitat characteristics associated with lamprey ammocoetes ( Lampetra spp.) were investigated at three different spatial scales: regional (Northern Ireland), catchment (Ballinderry River) and microhabitat. At the scale, more abundant in rivers a pH ≥8.2, while within catchment, abundance was negatively related to number of potential barriers distance upstream. microhabitat sites where present, median phi ≥1.94 (very coarse sand), sediment depth ≥11.5 cm, kurtosis >1.71. This...
Summary Optimisation of control methods invasive species using life‐history information may increase probability that techniques will be effective at reducing impacts nuisance species. The northern crayfish, Orconectes virilis , has negatively affected native flora and fauna throughout the world in areas where it is non‐native. Yet, life history populations rarely been studied. We investigated three introduced O . within Arizona streams mark–recapture a laboratory investigation reproduction...
The Colorado River in the Grand Canyon holds largest remaining population of Humpback Chub Gila cypha, an endangered fish endemic to basin. Early surveys 1990s found that most occupied Little and nearby areas mainstem were uncommon western (below Kanab Creek, at river kilometer [rkm] 257.2). From 1939 2002, was typically inundated by Lake Mead rkm 407 (at full pool). Since 2000, water levels have declined, current inflow is located almost 100 km downstream 503.1. Thus, Arizona Game Fish...
Abstract The freshwater pearl mussel Margaritifera margaritifera is endangered throughout Europe. Historically, mussels were described on the basis of shell characteristics. In more recent years with advent molecular techniques many ‘species’ molluscs have been found to be ecophenotypes. in numerous rivers Ireland and UK varying degrees superficial differences. It has thought that most divergent form Nore River, Ireland, m. durrovensis . current investigation considers shape differences...
ABSTRACT Two large dams on the Colorado River, Glen Canyon and Hoover Dam, have profoundly altered river within Grand Canyon. Owing to widespread drought increased water usage throughout Southwest, levels in Lake Mead declined by over 40 m since 2000, exposing 80 km of newly emerged riverine habitat western that experiences higher temperatures turbidity relative upstream portions River Our objective was investigate how probability fish occurrence has changed as abiotic conditions shifted...
Melanoides tuberculata Muller, 1774 (Thiaridae), a freshwater prosobranch snail native to regions of Asia and Africa, was introduced into the U.S. in 1960s is now found fifteen states. can affect communities directly by displacing species indirectly introducing foreign trematodes novel environments. As exact mechanisms displacement snails M. are unknown, egg predation rates on (Physella spp.) two different size classes (>30 mm 30 were consume Physella spp. only 2.8% consumed masses. None...
Abstract Glen Canyon Dam (GCD) on the Colorado River in northern Arizona provides water storage, flood control, and power system benefits to approximately 40 million people who rely energy resources basin. Downstream (e.g., angling, whitewater floating) National Recreation Area (GCNRA) Grand Park are impacted by operation of GCD. The GCD Adaptive Management Program was established 1997 monitor research effects dam operations downstream environment. We utilized secondary survey data an...
Background or typical levels of polychlorinated dibenzo-p-dioxins and dibenzo-p-furans in soils have become increasingly important the regulatory community, as dioxins come under increased scrutiny due to their toxicity persistence. Knowing dioxin is set levels, prevent further contamination, for setting cleanup levels. A random sample (n=54) agricultural lands within Washington state revealed a concentration "dioxin" 0.14 ng/kg (toxicity equivalents, TEQ). For comparison, residential urban...
White sands pupfish Cyprinodon tularosa were sampled with minnow traps along the length of Lost River, a highly variable desert stream in New Mexico, to evaluate if their abundance, median standard ( L S ) and sex ratio values differed by microhabitat variables. Habitat measurements made 4 m 2 area around trap. Sands populations primarily structured . As specific conductance surface increased, size fish decreased. Shallow areas higher correlated an increased number fish.
Our objectives were to determine which habitat variables had the greatest influence on densities of Three Forks springsnail (Pyrgulopsis trivialis) and pond snail (Physa gyrina), examine interactions between two species. We measured density several in Springs Boneyard Bog east-central Arizona. Density springsnails was (500/m2) shallow water (<5.6 cm), where snails less (<4.6/m2), closer springhead (<0.8 m). (66/m2) further away from (≥32 m) when temperatures greater (≥15.8°C). low (1.1/m2)...
Razorback sucker (Xyrauchen texanus) and flannelmouth (Catostomus latipinnis) live in sympatry the Colorado River basin. Although morphological intermediates have been described since 1889, hybrids were seemingly rare. Rarity of was likely attributed to razorback suckers' ability find conspecific mates throughout Dams segmented River, altering habitat isolating native fish populations. As a result, suckers became endangered. are uncommon hybridization could increase because limited mates. To...
Abstract Hybridization between two sucker species, Razorback Sucker Xyrauchen texanus and Flannelmouth Catostomus latipinnis , historically has occurred but been facilitated by anthropogenic habitat alteration. The ability to differentiate Suckers from hybrids is essential for the conservation management of endangered Sucker. purpose our study was investigate allometry—that is, how shape changes with length—of Sucker, their hybrids. were artificially spawned produce four progenies: female ×...