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Terrestrial and Aquatic Ecology

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Articles 901 - 930 of 1898

Full-Text Articles in Population Biology

Vertical Connectivity Influences Secondary Production, Community Diversity, And Resilience In An Ozark Stream, Nathan C. Dorff May 2019

Vertical Connectivity Influences Secondary Production, Community Diversity, And Resilience In An Ozark Stream, Nathan C. Dorff

Graduate Theses/Dissertations

The hyporheic zone, a key component of stream vertical connectivity, supports stream function (e.g., nutrient regeneration) and provides habitat for aquatic biota. The Ozark Highlands ecoregion contains gravel-bed streams that have extensive hyporheic zones and that are subject to recurrent flash floods. I sampled Leuctra tenuis(Pictet) nymphs from the hyporheic habitat (30-45 cm below the streambed) in a gravel-bed reach and an intermittent tributary of an Ozark stream from early instar to adult emergence. Concurrently, I sampled benthic insects in two reaches of the same stream that differed primarily in amount of hyporheic habitat (bedrock vs. gravel) and monitored …


Habitat Selection By American Beaverat Multiple Spatial Scales, Guiming Wang, Lance F. Mcclintic, Jimmy D. Taylor May 2019

Habitat Selection By American Beaverat Multiple Spatial Scales, Guiming Wang, Lance F. Mcclintic, Jimmy D. Taylor

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Semiaquatic mammals require both aquatic and terrestrial habitats, particularly interfaces between the two habitats. As ecosystem engineers, American beaver (Castor canadensis) consume and fell a great amount of deciduous trees. We tested the prediction that open water and amounts of food resources, including hardwood forests (i.e., deciduous trees as the dominant form of vegetation), herbaceous and woody wetlands, and shrubs, would influence the second-order habitat selection (i.e., placing home ranges on the landscape) by American beaver, whereas the third-order habitat selection of American beaver would be associated with woody wetland and shrub edges. We investigated hierarchical habitat selection by …


Epidemic Growth Rates And Host Movement Patterns Shape Management Performance For Pathogen Spillover At The Wildlife–Livestock Interface, Kezia R. Manlove, Laura M. Sampson, Benny Borremans, E. Frances Cassirer, Ryan S. Miller, Kim M. Pepin, Thomas E. Besser, Paul C. Cross May 2019

Epidemic Growth Rates And Host Movement Patterns Shape Management Performance For Pathogen Spillover At The Wildlife–Livestock Interface, Kezia R. Manlove, Laura M. Sampson, Benny Borremans, E. Frances Cassirer, Ryan S. Miller, Kim M. Pepin, Thomas E. Besser, Paul C. Cross

United States Department of Agriculture Wildlife Services: Staff Publications

Managing pathogen spillover at the wildlife–livestock interface is a key step towards improving global animal health, food security and wildlife conservation. However, predicting the effectiveness of management actions across host–pathogen systems with different life histories is an on-going challenge since data on intervention effectiveness are expensive to collect and results are system-specific.We developed a simulation model to explore how the efficacies of different management strategies vary according to host movement patterns and epidemic growth rates. The model suggested that fast-growing, fast-moving epidemics like avian influenza were best-managed with actions like biosecurity or containment, which limited and localized overall spillover risk. …


Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan May 2019

Assessing Populations Of Eastern Brook Trout (Salvelinus Fontinalis) Above And Below Waterfalls In Mountain Streams Of Virginia, Hannah Eisemann Macmillan

Masters Theses, 2010-2019

Anthropogenically driven factors, such as increasing temperature and sediment in valley streams, acidification of mountain streams, and the introduction of non-native trout, are restricting habitat suitable for healthy populations of eastern brook trout (Salvelinus fontinalis) throughout their native Appalachian range. Brook trout are important as predators of insects in mountain streams and as a favorite of anglers. It is crucial that remaining populations in sustainable habitats be identified and preserved. Waterfalls are geologic knickpoints preventing base-level lowering that create unique, stable landscapes above them, which may alleviate the temperature-productivity/acidity “habitat squeeze” for populations of brook trout and could …


Deicing Salts Influence Ranavirus Outbreaks In Wood Frog (Lithobates Sylvaticus) Tadpoles, Sarah Jacobson May 2019

Deicing Salts Influence Ranavirus Outbreaks In Wood Frog (Lithobates Sylvaticus) Tadpoles, Sarah Jacobson

Honors Scholar Theses

Ecosystems are increasingly being exposed to anthropogenic stressors that could make animals and thus populations more susceptible to disease. For example, the application of deicing salts to roads is increasing in the northeastern United States. Chronic stress that larval amphibians experience when living in vernal pools with high salinity may alter their susceptibility to ranavirus, a pathogen responsible for mass mortality events worldwide. This project quantifies the effects of road salts and ranavirus exposure on larval wood frog (Lithobates sylvaticus) growth and survival. Using outdoor mesocsoms, we raised wood frog tadpoles in salt treatments and then exposed them …


American White Pelicans, Tommy King May 2019

American White Pelicans, Tommy King

Wildlife Damage Management Technical Series

American white pelicans (Pelecanus erythrorhynchos, Figure 1) threaten aquaculture producers by direct predation and the spread of disease. They are also considered competition and a nuisance by some sports fishermen. Pelicans can also damage pond levees and crops, such as rice, by trampling the vegetation and depositing guano. A combination of wildlife damage management techniques is often necessary to reduce pelican damage to these resources. Aquaculture Prior to the winter of 1992, American white pelican depredations at catfish facilities in the Delta regions of Arkansas and Mississippi were limited, and birds were easily dispersed from the area. Since 1992, however, …


Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys May 2019

Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys

Graduate Theses and Dissertations

A common pattern across many taxonomic groups is that relatively few species are widespread while the majority are restricted in their geographic ranges. Such species distributions are used to inform conservation status, which poses unique challenges for rare or cryptic species. Further, priority status is often designated within geopolitical boundaries, which may include only a portion of a species range. This, coupled with lack of distributional data, has resulted in species being designated as apparently rare throughout some portions of their range, which may not accurately reflect their overall conservation need. The Interior Highlands region of the central United States …


Presence And Distribution Of Leptodactylus Guianensis Heyer And De Sa, 2011 In Colombia: Comparisons With Other Species In The L. Latrans Group., Mariela Osorno Muñoz, Doris L. Gutiérrez-Lamus, Rafael O. De Sá Apr 2019

Presence And Distribution Of Leptodactylus Guianensis Heyer And De Sa, 2011 In Colombia: Comparisons With Other Species In The L. Latrans Group., Mariela Osorno Muñoz, Doris L. Gutiérrez-Lamus, Rafael O. De Sá

Biology Faculty Publications

Leptodactylus guianensis is reported for the first time for Colombia along with a distributional map of the species. The species is the fifth species of the L. latransspecies group documented in the country. Males possess a single, conical and slightly chisel-shaped thumb spine; only three species in the group have a single thumb spine. In collections, specimens of L. guianensis are misidentified as L. macrosternum, L. latrans or L. bolivianus. We provide morphological, colouration and habitat descriptions for where the species occurs in Colombia.


Board Invited Review: Prospects For Improving Management Of Animal Disease Introductions Using Disease-Dynamic Models, Ryan S. Miller, Kim M. Pepin Apr 2019

Board Invited Review: Prospects For Improving Management Of Animal Disease Introductions Using Disease-Dynamic Models, Ryan S. Miller, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Management and policy decisions are continually made to mitigate disease introductions in animal populations despite often limited surveillance data or knowledge of disease transmission processes. Science-based management is broadly recognized as leading to more effective decisions yet application of models to actively guide disease surveillance and mitigate risks remains limited. Disease-dynamic models are an efficient method of providing information for management decisions because of their ability to integrate and evaluate multiple, complex processes simultaneously while accounting for uncertainty common in animal diseases. Here we review disease introduction pathways and transmission processes crucial for informing disease management and models at the …


Quantifying Atlantic Sea Scallop (Placopecten Magellanicus) Larval Abundance Throughout Cape Elizabeth, Maine, Hannah Haskell, Britney Evangelista, Alex Loftis Apr 2019

Quantifying Atlantic Sea Scallop (Placopecten Magellanicus) Larval Abundance Throughout Cape Elizabeth, Maine, Hannah Haskell, Britney Evangelista, Alex Loftis

Thinking Matters Symposium Archive

As markets for the Atlantic Sea scallop are growing, the need for sustainable and reliable harvesting methods such as aquaculture is more imperative than ever. Due to the difficulty of maintaining sea scallop hatcheries, scallop farmers typically collect larvae from the ocean and raise them until a marketable size on lease sites. In order to efficiently collect scallop larvae, being able to predict when the larvae are most abundant in the water column is crucial. The goal of our research was to learn when scallop larvae are most abundant in the water column and to determine if there is a …


Expanded Phenotypic Diagnoses For 24 Recently Named New Taxa Of Hesperiidae (Lepidoptera), Nick V. Grishin Mar 2019

Expanded Phenotypic Diagnoses For 24 Recently Named New Taxa Of Hesperiidae (Lepidoptera), Nick V. Grishin

The Taxonomic Report of the International Lepidoptera Survey

Expanded diagnoses by phenotypic characters for the 24 new taxa named in the article "Genomes of skipper butterflies reveal extensive convergence of wing patterns" by Li, W., Cong, Q., Shen, J., Zhang, J., Hallwachs, W., Janzen, D.H. and Grishin, N.V., 2019 and published in the Proceedings of the National Academy of Sciences of the United States of America on March 15, 2019 are provided and illustrated. More detailed diagnoses will help identifying these phylogenetic groups by their wing patterns and shapes and other morphological characters including the structures of antennae and genitalia using this single publication, instead of obtaining the …


Population Characteristics Of Co-Managed White Bass And Hybrid Striped Bass In Lake Mcconaughy, Nebraska, Benjamin J. Schall, Casey W. Schoenebeck, Keith D. Koupal Mar 2019

Population Characteristics Of Co-Managed White Bass And Hybrid Striped Bass In Lake Mcconaughy, Nebraska, Benjamin J. Schall, Casey W. Schoenebeck, Keith D. Koupal

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

White Bass (Morone chrysops) and Hybrid Striped Bass (M. saxatillis × M. chrysops) populations often coexist in the same waterbody and are known to achieve different lengths, have differing reproductive success, and provide different opportunities for anglers. However, comparative population dynamics from systems where Moronids are managed with the same regulation is often lacking. This study aimed to assess the recruitment, mortality, and growth of these species from seasonal samples collected at Lake McConaughy in 2015 and fall 2016. White Bass demonstrated highly variable recruitment in Lake McConaughy despite stocking efforts (mean recruitment variability index = …


Improving Risk Assessment Of The Emergence Of Novel Influenza A Viruses By Incorporating Environmental Surveillance, Kim M. Pepin, Matthew W. Hopken, Susan A. Shriner, Erica Spackman, Zaid Abdo, Colin Parrish, Steven Steven, James O. Lloyd-Smith, Antoinette J. Piaggio Mar 2019

Improving Risk Assessment Of The Emergence Of Novel Influenza A Viruses By Incorporating Environmental Surveillance, Kim M. Pepin, Matthew W. Hopken, Susan A. Shriner, Erica Spackman, Zaid Abdo, Colin Parrish, Steven Steven, James O. Lloyd-Smith, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Reassortment is an evolutionary mechanism by which influenza A viruses (IAV) generate genetic novelty. Reassortment is an important driver of host jumps and is widespread according to retrospective surveillance studies.However, predicting the epidemiological risk of reassortant emergence in novel hosts from surveillance data remains challenging. IAV strains persist and cooccur in the environment, promoting co-infection during environmental transmission. These conditions offer opportunity to understand reassortant emergence in reservoir and spillover hosts. Specifically, environmental RNA could provide rich information for understanding the evolutionary ecology of segmented viruses, and transform our ability to quantify epidemiological risk to spillover hosts. However, significant challenges …


Spatial And Temporal Variability In Post-Larval Yellow Perch Density, Steve Hauschildt Feb 2019

Spatial And Temporal Variability In Post-Larval Yellow Perch Density, Steve Hauschildt

Biology Graduate Theses

Yellow Perch Perca flavescens are important as forage for other species and for sport fishing in many northern lakes. However, estimating post-larval Yellow Perch populations can be difficult because of many environmental factors that cause unexplained variation. The objective of this study was to help reduce unexplained variation by determining a post-larval Yellow Perch population density estimate on Blackduck Lake, MN, provide guidance to help determine the number of trawls required for trawling-based recruitment indices to achieve varying levels of precision, and test for the effects of wind speed and direction on post-larval Yellow Perch spatial variability. This study estimated …


Individual-Level Antibody Dynamics Reveal Potential Drivers Of Influenza A Seasonality In Wild Pig Populations, Kim M. Pepin, Kerri Pedersen, Xiu-Feng Wan, Fred L. Cunningham, Colleen T. Webb, Mark Q. Wilber Jan 2019

Individual-Level Antibody Dynamics Reveal Potential Drivers Of Influenza A Seasonality In Wild Pig Populations, Kim M. Pepin, Kerri Pedersen, Xiu-Feng Wan, Fred L. Cunningham, Colleen T. Webb, Mark Q. Wilber

United States Department of Agriculture Wildlife Services: Staff Publications

Swine are important in the ecology of influenza A virus (IAV) globally. Understanding the ecological role of wild pigs in IAV ecology has been limited because surveillance in wild pigs is often for antibodies (serosurveillance) rather than IAVs, as in humans and domestic swine. As IAV antibodies can persist long after an infection, serosurveillance data are not necessarily indicative of current infection risk. However, antibody responses to IAV infections cause a predictable antibody response, thus time of infection can be inferred from antibody levels in serological samples, enabling identification of risk factors of infection at estimated times of infection. Recent …


Comparing Orientation Behavior And Prey Preference Of Leptasterias Spp. Between Microhabitats, Jenna C. Sanders, Margaret W. Johnson, C Sarah Cohen Jan 2019

Comparing Orientation Behavior And Prey Preference Of Leptasterias Spp. Between Microhabitats, Jenna C. Sanders, Margaret W. Johnson, C Sarah Cohen

STAR Program Research Presentations

Leptasterias spp. is a species complex of small, six rayed, predatory sea stars that inhabit rocky intertidal communities along the Pacific coast of North America. A developmental mode of brooding their young, rather than broadcasting for planktonic development, limits dispersal away from the natal area, and may also result in fine scale local adaptation of populations. Local adaptation may lead to morphological and behavioral differences among populations, specifically towards the most available prey. Within the rocky intertidalthere are zones of high and low wave impact which create microhabitats with their own selective forces. In areas of high wave impact, stars …


Biodiversity And Conservation Study Of The St. Norbert Abbey, De Pere, Wisconsin - 2018 Annual Report, Nick Moran, Mya Mcdaniel, Adam L. Brandt Jan 2019

Biodiversity And Conservation Study Of The St. Norbert Abbey, De Pere, Wisconsin - 2018 Annual Report, Nick Moran, Mya Mcdaniel, Adam L. Brandt

Student Creative and Scholarly Works

Long term biological studies are rare but incredibly valuable for examining natural phenomena. Data collected over many years or decades allows for analyses of trends that would never be apparent in a single season. The research presented here is the completion of the second annual field season of a long term study to analyze biodiversity trends at the St. Norbert Abbey. Using visual searches, live trapping, and trail cameras, the biodiversity and abundance of species were examined. Special emphasis was placed on small mammals, though other groups were observed and documented. The goals of this project are to (1) collect …


Effects Of Rainbow Trout On Brook Trout Population Size In Tributaries To Lake Superior In Cook County, Minnesota, Craig Tangren Jan 2019

Effects Of Rainbow Trout On Brook Trout Population Size In Tributaries To Lake Superior In Cook County, Minnesota, Craig Tangren

Journal of Earth and Life Science

This study looked at the effects of Rainbow Trout stocking on the size of Brook Trout populations above migratory barriers. Linear mixed effects models were used to determine if there was a relationship between Brook Trout and Rainbow Trout catch rates. Age 1 or older Brook Trout populations were influenced by relative abundance of age 1 or older Rainbow Trout, according to the best supported model based on AIC scores. Population responses varied by stream, ranging along a gradient from high catch rates with a positive relationship to a negative relationship with low relative abundances. Streams with a positive relationship …


Multiple Connections Between Amazonia And Atlantic Forest Shaped The T Phylogenetic And Morphological Diversity Of Chiasmocleis Mehely, 1904 (Anura: Microhylidae: Gastrophryninae), Rafael O. De Sá, João Filipe Riva Tonini, Hannah Van Huss, Alex Long, Travis Cuddy, Mauricio C. Forlani, Pedro L.V. Peloso, Hussam Zaher, Célio F.B. Haddad Jan 2019

Multiple Connections Between Amazonia And Atlantic Forest Shaped The T Phylogenetic And Morphological Diversity Of Chiasmocleis Mehely, 1904 (Anura: Microhylidae: Gastrophryninae), Rafael O. De Sá, João Filipe Riva Tonini, Hannah Van Huss, Alex Long, Travis Cuddy, Mauricio C. Forlani, Pedro L.V. Peloso, Hussam Zaher, Célio F.B. Haddad

Biology Faculty Publications

Chiasmocleis is the most species-rich genus of Neotropical microhylids. Herein, we provide the first comprehensive multilocus phylogeny for the genus, including all but 3 of the 34 recognized species and multiple individuals per species. We discuss cryptic speciation, species discovery, patterns of morphological evolution, and provide a historical biogeographic analysis to account for the current distribution of the genus. Diversification of Chiasmocleis from other New World microhylids began during the Eocene, app. 40 mya, in forested areas, and current diversity seems to be a product of recurrent connections between the Atlantic Forest and Amazonia. Small-sized species evolved independently three times …


Tiger Sharks Eat Songbirds: Reply, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, A. E. Jefferson, A. M. Kroetz, Sean P. Powers, E. A. Seubert Jan 2019

Tiger Sharks Eat Songbirds: Reply, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, A. E. Jefferson, A. M. Kroetz, Sean P. Powers, E. A. Seubert

University Faculty and Staff Publications

In response to our recent paper (Drymon et al. 2019), Yosef (2019) questions the mechanism proposed to explain interactions between tiger sharks (Galeocerdo cuvier) and migratory songbirds, while offering an alternative mechanism based on a single observation. We appreciate the comments from Yosef and the opportunity to respond.


Comparison Of Conservation Policy Benefits For An Umbrella And Related Sagebrush-Obligate Species, Jonathan B. Dinkins, Jeffrey L. Beck Jan 2019

Comparison Of Conservation Policy Benefits For An Umbrella And Related Sagebrush-Obligate Species, Jonathan B. Dinkins, Jeffrey L. Beck

Human–Wildlife Interactions

Many conservation strategies promote the potential of multiple species benefitting from protection of large areas necessary for the continued viability of 1 species. One prominent strategy in western North America is Wyoming’s Sage-grouse Core Area Policy, which was designed to conserve greater sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) breeding habitat, but may also serve as an umbrella to conserve other sagebrush (Artemisia spp.)-obligate wildlife, including songbirds. Sagebrush-obligate songbirds and sage-grouse have undergone population declines throughout the western United States attributed to similar habitat issues. We compared trends of sagebrush-obligate songbirds from the Breeding Bird Survey and sage-grouse lek …


Examining Black Bullhead Ameiurus Melas Age And Growth In Shallow Minnesota Lakes, Michael S. Collins, Anna M. Medina Jan 2019

Examining Black Bullhead Ameiurus Melas Age And Growth In Shallow Minnesota Lakes, Michael S. Collins, Anna M. Medina

Journal of Earth and Life Science

Ageing methods, population age structures, and growth trajectories for Black Bullhead Ameiurus melas were evaluated for six populations from shallow lakes divided between two ecoregions in Minnesota, USA. A total of 693 fish were collected in July and August 2018 and measured for total lengths (TL) and weights (g). We collected ageing structures from 320 of these fish. Crosssections of lapillar otoliths (n=191) and pectoral spine structures (n=75) were used to estimate age by two readers in a blind reading procedure. Fish caught ranged in total lengths from ~40 to 350 mm and weighed between 8 and 380 g. Black …


Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen Jan 2019

Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Amphibians are facing global declines due to climate change, loss and degradation of habitat, invasive species, and disease. The Appalachian region of the eastern USA is a global biodiversity hotspot for salamanders, which are considered keystone species that influence nutrient dynamics in terrestrial and aquatic food webs. There are high rates of salamander endemism in the Appalachian region, with many species restricted to isolated, high elevation areas. The Cow Knob Salamander (Plethodon punctatus) is one such species. It is only found at elevations >675 m (most populations are above 900 m) on Shenandoah Mountain, North Mountain, and Nathaniel …


The Effects Of Management Practices On Grassland Birds: An Introduction To North American Grasslands And The Practices Used To Manage Grasslands And Grassland Birds, Jill A. Shaffer, John P. Delong Jan 2019

The Effects Of Management Practices On Grassland Birds: An Introduction To North American Grasslands And The Practices Used To Manage Grasslands And Grassland Birds, Jill A. Shaffer, John P. Delong

Papers in Ornithology

Summary

The Great Plains of North America is defined as the land mass that encompasses the entire central portion of the North American continent that, at the time of European settlement, was an unbroken expanse of primarily herbaceous vegetation. The Great Plains extend from central Saskatchewan and Alberta to central Mexico and from Indiana to the Rocky Mountains. The expanses of herbaceous vegetation are often referred to as native prairie or native grasslands. Native grasslands share the characteristics of a general uniformity in vegetation structure, dominance by grasses and forbs, a near absence of trees and shrubs, annual precipitation ranging …


Taking The Bait: Species Taking Oral Rabies Vaccine Baits Intended For Raccoons, Betsy S. Haley, Are R. Berentsen, Richard M. Engeman Jan 2019

Taking The Bait: Species Taking Oral Rabies Vaccine Baits Intended For Raccoons, Betsy S. Haley, Are R. Berentsen, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Raccoon rabies in eastern USA is managed by strategically distributing oral rabies vaccine (ORV) baits. The attractiveness, palativity, density, and non-target species bait take affect ORV effectiveness. We examined raccoon and non-target species differences in investigating/removing fish-meal polymer and coated sachet baits applied to simulate two aerial bait distribution densities. Bait densities of 150 baits/km2 and 75 baits/km2 were evaluated, respectively, in zones expected to have high and low

Racc oon densities. Three primary non-target species visited baits: coyotes, white-tailed deer, and feral swine. The proportion of bait stations visited by raccoons during 1 week observation periods ranged from 50 …


Using Unmanned Aerial Vehicles For Bird Harassment On Fish Ponds, Ciera A. Rhoades, Peter J. Allen, D. Tommy King Jan 2019

Using Unmanned Aerial Vehicles For Bird Harassment On Fish Ponds, Ciera A. Rhoades, Peter J. Allen, D. Tommy King

United States Department of Agriculture Wildlife Services: Staff Publications

The effects of aquaculture decline on piscivorous birds in the Mississippi Delta concern catfish farmers, with possible increases in fish loss and disease transmission. Piscivorous birds quickly habituate to most current methods of harassment (loud noises and visual disturbances) leading to increased depredation and disease. Our study was designed to test the efficacy of using unmanned aerial vehicles (UAVs) to effectively control piscivorous birds at fish farms. We hypothesized that a UAV would be more efficient at reducing the number of fish-eating birds on fish ponds than current forms of harassment. We conducted pre-treatment bird surveys, harassment observations, and post-treatment …


Effectiveness Of Snap And A24-Automated Traps And Broadcast Anticoagulant Bait In Suppressing Commensal Rodents In Hawaii, Aaron B. Shiels, Tyler Bogardus, Jobriath Rohrer, Kapua Kawelo Jan 2019

Effectiveness Of Snap And A24-Automated Traps And Broadcast Anticoagulant Bait In Suppressing Commensal Rodents In Hawaii, Aaron B. Shiels, Tyler Bogardus, Jobriath Rohrer, Kapua Kawelo

Human–Wildlife Interactions

Commensal rodents (invasive rats, Rattus spp.; house mice, Mus musculus) are well established globally. They threaten human health by disease transfer and impact economies by causing agricultural damage. On island landscapes, they are frequent predators of native species and affect biodiversity. To provide managers with better information regarding methods to suppress commensal rodent populations in remote island forests, in 2016 we evaluated the effectiveness of continuous rat trapping using snap-traps, Goodnature®A24 self-resetting rat traps, and a 1-time (2-application) hand-broadcast of anticoagulant rodenticide bait pellets (Diphacinone-50) applied at 13.8 kg/ha per application in a 5-ha forest on Oahu, …


Tiger Sharks Eat Songbirds: Scavenging A Windfall Of Nutrients From The Sky, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, E. A. Seubert, A. E. Jefferson, A. M. Kroetz, Sean P. Powers Jan 2019

Tiger Sharks Eat Songbirds: Scavenging A Windfall Of Nutrients From The Sky, J. Marcus Drymon, K. Feldheim, A. M.V. Fournier, E. A. Seubert, A. E. Jefferson, A. M. Kroetz, Sean P. Powers

University Faculty and Staff Publications

No abstract provided.


Freshwater And Marine Survival Of Coho Salmon (Oncorhynchus Kisutch) As A Function Of Juvenile Life History, Grace Katherine Ghrist Jan 2019

Freshwater And Marine Survival Of Coho Salmon (Oncorhynchus Kisutch) As A Function Of Juvenile Life History, Grace Katherine Ghrist

Cal Poly Humboldt theses and projects

Juvenile Coho Salmon (Oncorhynchus kisutch) in coastal California streams exhibit various life history strategies during their freshwater development. One strategy of interest to managers and conservationists is the early migrant. Juvenile early migrants emigrate from natal habitat into lower parts of the watershed or estuary during their first fall or winter, where they rear before migration to the ocean. By contrast, the more prevalent spring migrant resides in natal reaches over the winter and migrates directly to the ocean the following spring. Salmon monitoring programs generally estimate juvenile production and demographic rates using only spring migrants, and these …


Using Environmental Dna And Occupancy Modeling To Estimate Rangewide Metapopulation Dynamics Of The Endangered Tidewater Goby Eucyclogobius Spp., Chad M. Martel Jan 2019

Using Environmental Dna And Occupancy Modeling To Estimate Rangewide Metapopulation Dynamics Of The Endangered Tidewater Goby Eucyclogobius Spp., Chad M. Martel

Cal Poly Humboldt theses and projects

Conservation of species is most effective when metapopulation dynamics are well understood and incorporated into management plans, allowing managers to target conservation efforts where they will be most effective. The development of environmental DNA (eDNA) methods provides an efficient and highly sensitive approach to generate presence and absence data needed to elucidate metapopulation dynamics. Combining sample detection histories from eDNA surveys with occupancy models that account for non-detection can offer unbiased estimates of rangewide metapopulation dynamics. However, traditional occupancy models do not allow direct evaluation of the drivers of site occupancy, extinction, and colonization. Herein, I utilize a novel dynamic …