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Terrestrial and Aquatic Ecology

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Articles 361 - 390 of 964

Full-Text Articles in Biology

Ecological Analyses Of Macroinvertebrates And Fish Species In Six Streams On A Louisiana Military Base From 2001 To 2019, Danielle Joerger May 2020

Ecological Analyses Of Macroinvertebrates And Fish Species In Six Streams On A Louisiana Military Base From 2001 To 2019, Danielle Joerger

Biology Theses

An in-depth ecological analysis of how and why the aquatic community changes over time was conducted for 6 streams on the Fort Polk military base in Louisiana using data collected from 2001 to 2019. Fort Polk is a unique location as nineteen first-order streams are located on the premises belonging to three separate drainages. The primary goal was to determine whether temporal or between-drainage variation has a larger effect on community structure. To accomplish this the effects of disturbance on fish and macroinvertebrate assemblages was determined temporally and between drainages. Several hypotheses were drawn from this: 1) temporally, assemblages exhibit …

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Habitat Selection And Host Detection In The Salamander Mussel, Simpsonaias Ambigua, Eric A. Stegmann May 2020

Habitat Selection And Host Detection In The Salamander Mussel, Simpsonaias Ambigua, Eric A. Stegmann

Graduate Theses/Dissertations

The native freshwater mussels, Order Unionida, have suffered many species extinctions and loss of abundance. Two important threats to native mussels are loss of habitat and loss of access to the vertebrate hosts of the parasitic mussel larvae. The Salamander mussel, Simpsonaias ambigua, is a habitat specialist, living under flat rocks. It is often found in direct association with its only known host, the common mudpuppy, Necturus maculosus. This association could result from movement and habitat selection by the mussels themselves. Alternatively, it might result from the deposition of juveniles by a resident host. Habitat selection and host …

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Can Desert Mosses Hide From Climate Change? The Ecophysiological Importance Of Habitat Buffering & Water Relations To A Keystone Biocrust Moss In The Mojave Desert, Theresa Ann Clark May 2020

Can Desert Mosses Hide From Climate Change? The Ecophysiological Importance Of Habitat Buffering & Water Relations To A Keystone Biocrust Moss In The Mojave Desert, Theresa Ann Clark

UNLV Theses, Dissertations, Professional Papers, and Capstones

Empirical and observational studies suggest a keystone biocrust moss, Syntrichia caninervis, may be sensitive to future climate change in the American Southwest due to its uniquely sensitive water relations that appear particularly challenged during summer hydration-desiccation cycles. However, the potential mitigating roles of habitat buffering, acclimatization, and winter recovery on the vulnerability of this species remain largely unexplored. I investigated potential abiotic and biotic resiliency factors driving summer stress resistance and recovery in S. caninervis along present-day aridity gradients in the Mojave Desert to strengthen the climate change vulnerability assessment for this species common to biocrusts of North America, northern …

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Dragonflies And Damselflies (Insecta: Odonata) As Indicators For Riparian Condition In Ozark Spring Streams, Cameron Riley Cheri May 2020

Dragonflies And Damselflies (Insecta: Odonata) As Indicators For Riparian Condition In Ozark Spring Streams, Cameron Riley Cheri

Graduate Theses/Dissertations

The Odonata (dragonflies and damselflies) are often ineffectively sampled during standard stream bioassessments in North America. Subsequently, odonates are not frequently regarded as informative taxa for stream assessment, particularly when monitoring the ecological impacts of organic pollution. I hypothesized that stream-dwelling odonates should be more useful bioindicators for the assessment of riparian conditions surrounding streams because vegetation associated with streams is used for oviposition, roosting and to establish breeding territories. I selected twelve Ozark spring streams that satisfied a broad array of riparian conditions for study. I sampled each stream’s odonate and total benthic community along with both instream and …

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Investigating The Effects Of Sea-Level Rise And Increasing Salinity On Procambarus Lunzi Of Sapelo Island, Georgia, Samuel Long Apr 2020

Investigating The Effects Of Sea-Level Rise And Increasing Salinity On Procambarus Lunzi Of Sapelo Island, Georgia, Samuel Long

Biology Theses

Barrier islands have great ecological and economical importance and face a threat from increasing sea-level due to climate change. Erosion of existing freshwater lens and ocean inundation could greatly change freshwater availability on the island. This could have significant impacts on freshwater crayfish like Procambarus lunzi, which are complexly intertwined into the trophic food web of the island. This study’s goal was to investigate the salinity tolerance of this crayfish on Sapelo Island, Georgia, in an attempt to predict the possible effects and response to sea-level rise by this crayfish. Crayfish were wild-caught from the island in March, June, and …

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Impacts Of Invasive Rats And Tourism On A Threatened Island Bird: The Palau Micronesian Scrubfowl, Paul M. Radley, Robert A. Davis, Tim S. Doherty Apr 2020

Impacts Of Invasive Rats And Tourism On A Threatened Island Bird: The Palau Micronesian Scrubfowl, Paul M. Radley, Robert A. Davis, Tim S. Doherty

Research outputs 2014 to 2021

Invasive predators have decimated island biodiversity worldwide. Rats (Rattus spp.) are perhaps the greatest conservation threat to island fauna. The ground nesting Palau Micronesian Scrubfowl Megapodius laperouse senex (Megapodiidae) inhabits many of the islands of Palau's Rock Island Southern Lagoon Conservation Area (RISL) in the western Pacific. These islands are also heavily visited by tourists and support populations of introduced rats, both of which may act as added stressors for the scrubfowl. Using passive chew-tag and call playback surveys on five tourist-visited and five tourist-free islands, we investigated if rats and tourists negatively affect scrubfowl, and if higher rat activity …

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135— Coral-Sponge Interactions On Rocky Point Reef, San Salvador, Bahamas, Michael Harvey, Anna Meichenbaum, Brooke Stickles Apr 2020

135— Coral-Sponge Interactions On Rocky Point Reef, San Salvador, Bahamas, Michael Harvey, Anna Meichenbaum, Brooke Stickles

GREAT Day Posters

We surveyed the intensity of competition for reef space between sponges and corals at the Rocky Point patch reef adjacent to San Salvador Island, The Bahamas. Our working hypothesis was that, because of a dearth of predators, fast growing, chemically unprotected sponges more likely to be involved in competitive interactions. Results indicate that competition for reef space was widespread, but contrary to our hypothesis no sponge or coral species was disproportionately more involved in these interactions. These results contradict previous studies on Rocky Point reef and in our discussion we propose an explanation for this discrepancy.

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Combined Opportunistic And Equilibrium Life-History Traits Facilitate Successful Invasions Of The Shimofuri Goby (Tridentiger Bifasciatus), Jiao Qin, Miao Xiang, Meixiang Jia, Fei Cheng, Bjorn V. Schmidt, Jian Liu, Songguang Xie Apr 2020

Combined Opportunistic And Equilibrium Life-History Traits Facilitate Successful Invasions Of The Shimofuri Goby (Tridentiger Bifasciatus), Jiao Qin, Miao Xiang, Meixiang Jia, Fei Cheng, Bjorn V. Schmidt, Jian Liu, Songguang Xie

Faculty Publications

The life-history traits of a non-native population of Shimofuri goby (Tridentiger bifasciatus) were investigated in Nansi Lake, which is a storage lake on the East Route of the South-to-North Water Transfer Project, China. The results were analyzed in combination with data from other non-native populations of this species to reveal the life-history traits that caused its successful invasions. Mature gonads in April and May suggest that the species spawns in this period, and cohort tracking and age analysis revealed that individuals had a one-year lifespan. The relative fecundity was 2,825 ± 614 eggs/g. A short lifespan and high fecundity are …

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West Coast Rock Lobster Whale Entanglement Mitigation Workshop, Jason How, L Orme, Graeme Baudains, Pia Dobson, M Taylor, Simon De Lestang Apr 2020

West Coast Rock Lobster Whale Entanglement Mitigation Workshop, Jason How, L Orme, Graeme Baudains, Pia Dobson, M Taylor, Simon De Lestang

Fisheries Occasional Publications

No abstract provided.

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The Impact Of Nicotine Accumulation Exposure On Lithobates Catebeianus Larvae Mortality, Luke Micek Apr 2020

The Impact Of Nicotine Accumulation Exposure On Lithobates Catebeianus Larvae Mortality, Luke Micek

UCARE: Research Products

Cigarette butts are the most littered item in the world and contain over 4,000 chemicals, including the organic compound nicotine (Slaughter et al. 2011). Billions of cigarette butts are littered each year which may wash into bodies of water, impacting the local wildlife. To determine how introduced chemicals impact the environment, it is important to study its effects on indicator species. Amphibians, such as Lithobates catebeianus, act as indicator species due to their extreme sensitivity to chemical changes in its environment. The purpose of this research project was to obtain data to help determine the impact nicotine accumulation has …

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Diatom Voucher Flora And Comparison Of Collection Methods For Biodiversity Hotspot Upper Three Runs Creek, Katie M. Johnson Mar 2020

Diatom Voucher Flora And Comparison Of Collection Methods For Biodiversity Hotspot Upper Three Runs Creek, Katie M. Johnson

Biology Theses

Surface freshwater is a scarce resource. Due to the scarcity and necessity of this resource, it is imperative that its quality is routinely monitored. One way of monitoring water quality is through biological assessments, which include examining algal assemblages. Regionally, little remains known of algal taxa in the southeastern United States. In the past, the Academy of Natural Sciences of Philadelphia (ANSP) conducted biological assessments along the Savannah River finding Gomphonema parvulum (Kützing) Kützing 1849 to be a dominant taxon rendering assessments inconclusive. Recent studies have provided evidence that species complexes and semi-cryptic taxa have been identified within the Gomphonema …

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Do Foliar Endophytes Matter In Litter Decomposition?, Emily R. Wolfe, Daniel J. Ballhorn Mar 2020

Do Foliar Endophytes Matter In Litter Decomposition?, Emily R. Wolfe, Daniel J. Ballhorn

Biology Faculty Publications and Presentations

Litter decomposition rates are affected by a variety of abiotic and biotic factors, including the presence of fungal endophytes in host plant tissues. This review broadly analyzes the findings of 67 studies on the roles of foliar endophytes in litter decomposition, and their effects on decomposition rates. From 29 studies and 1 review, we compiled a comprehensive table of 710 leaf-associated fungal taxa, including the type of tissue these taxa were associated with and isolated from, whether they were reported as endo- or epiphytic, and whether they had reported saprophytic abilities. Aquatic (i.e., in-stream) decomposition studies of endophyte-affected litter were …

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The Mangroves Of Costa Rica, Kylie Stewart Feb 2020

The Mangroves Of Costa Rica, Kylie Stewart

Honors Projects

Mangroves are a type of coastal vegetation present in the intertidal zone of tropical and subtropical climates. This paper explores the mangroves of Costa Rica, their significance, and various strategies the country utilizes in order to protect mangrove forests. Several books and articles about mangroves and conservationism are examined to explain why mangrove forests are vital to a coastline’s health and growth. The scholarly topic pertains to mangroves located in the United States and Costa Rica along with methods used to maintain the wildlife that live within them. The concept of ecotourism will be explored and how mangrove forests are …

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The Role Of Dislodgement In The Territorial Ecology Of The Owl Limpet, Lottia Gigantea, Ryan T. Kabala, Natalie Swinford, Maria J. Mason, William G. Wright Feb 2020

The Role Of Dislodgement In The Territorial Ecology Of The Owl Limpet, Lottia Gigantea, Ryan T. Kabala, Natalie Swinford, Maria J. Mason, William G. Wright

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Ascertaining the risks and benefits of different behaviors is a central goal of research on territoriality. Although most territorial behavior is ritualized, with concomitant reduced risks for both residents and intruders, this ritualization is generally found to be underpinned by rare, highly consequential, interactions. The agonistic behavior of the intertidal owl limpet, Lottia gigantea, involves defense of a feeding territory, and includes a relatively explosive thrusting response by territory holders against intruding conspecifics. We here ask whether this thrusting behavior is capable of entirely dislodging intruders from their rocky wave-swept substratum, thereby ridding the resident of future challenges by …

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Range Extension For Dekay’S Brownsnake (Storeria Dekayi) In South-Central Nebraska, Macy K. Cool, Keith Geluso Feb 2020

Range Extension For Dekay’S Brownsnake (Storeria Dekayi) In South-Central Nebraska, Macy K. Cool, Keith Geluso

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

Dekay’s Brownsnake (Storeria dekayi) generally occurs in southeastern parts of the state, where the species was known from 16 counties. Herein, we update the distribution of S. dekayi in the state and briefly comment on habitat and abundance from observations in September and October 2018. We documented 7 new county records that extend its distribution in south-central Nebraska. We observed that S. dekayi does not only reside in mesic wooded habitats in Nebraska but also occupies open environments, including areas with upland grasslands and row-crop agriculture. Dekay’s Brownsnake currently is listed as a species of concern …

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Seedling Survival Declines With Increasing Conspecific Density In A Common Temperate Tree, Fiona V. Jevon, Sydne Record, John Grady, Ashley K. Lang, David A. Orwig, Matthew P. Ayres, Jaclyn H. Matthes Jan 2020

Seedling Survival Declines With Increasing Conspecific Density In A Common Temperate Tree, Fiona V. Jevon, Sydne Record, John Grady, Ashley K. Lang, David A. Orwig, Matthew P. Ayres, Jaclyn H. Matthes

Biology Faculty Research and Scholarship

Feedbacks between plants and their soil microbial communities often drive negative density dependence in rare, tropical tree species, but their importance to common, temperate trees remains unclear. Additionally, whether negative density dependence is driven by natural enemies (e.g., soil pathogens) or by high densities of seedlings has rarely been assessed. Density dependence may also depend on seedling size, as smaller and/or younger seedlings may be more susceptible to mortality agents. We monitored seedlings of Quercus rubra, a common, canopy‐dominant temperate tree, to investigate how the density of neighboring adults and seedlings influenced their survival over two years. We assessed …

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Using Northern Pike And Yellow Perch To Attempt A Trophic Cascade, Bryan Sea Jan 2020

Using Northern Pike And Yellow Perch To Attempt A Trophic Cascade, Bryan Sea

Journal of Earth and Life Science

In the midwestern USA, water clarity has decreased in shallow lakes as a result of large populations of Fathead Minnow Pimephales promelas and agriculture that impact the life that depend on shallow habitats, such as waterfowl, fish, and aquatic plants. Northern Pike Esox lucius and Yellow Perch Perca flavescens were stocked in a few lakes in attempt to create a tropic cascade and reduce populations of nuisance Fathead Minnows. Northern Pike were stocked as fry and Yellow Perch were stocked as adults either pre-spawn or post-spawn. Lake managers hypothesized adult Yellow Perch would spawn and the age-0 Perch would feed …

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Direct And Indirect Effects Of Sex Steroids On Gonadotrope Cell Plasticity In The Teleost Fish Pituitary, Romain Fontaine, Muhammad Rahmad Royan, Kristine Von Krogh, Finn-Arne Weltzien, Dianne M. Baker Jan 2020

Direct And Indirect Effects Of Sex Steroids On Gonadotrope Cell Plasticity In The Teleost Fish Pituitary, Romain Fontaine, Muhammad Rahmad Royan, Kristine Von Krogh, Finn-Arne Weltzien, Dianne M. Baker

Biological Sciences Research

The pituitary gland controls many important physiological processes in vertebrates, including growth, homeostasis, and reproduction. As in mammals, the teleost pituitary exhibits a high degree of plasticity. This plasticity permits changes in hormone production and secretion necessary to meet the fluctuating demands over the life of an animal. Pituitary plasticity is achieved at both cellular and population levels. At the cellular level, hormone synthesis and release can be regulated via changes in cell composition to modulate both sensitivity and response to different signals. At the cell population level, the number of cells producing a given hormone can change due to …

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Examining A Fish Community And Its Response To Coastal Restoration In A Dynamic Coastal Estuary, Richard Mahoney Jan 2020

Examining A Fish Community And Its Response To Coastal Restoration In A Dynamic Coastal Estuary, Richard Mahoney

Electronic Theses and Dissertations, 2020-2023

Globally, coastal habitats are experiencing degradation due to the increase of human population growth, development along coastlines, and a constantly changing climate. This threatens the future production of critical ecosystem services such as shoreline stabilization, water filtration, nursery grounds for marine fauna, and many more. To combat these losses, resource managers are actively restoring coastal habitat. Past research suggests restoring habitats has mixed results; numerous factors influence restoration success. This study is among the first to assess the nekton community in the Matanzas River estuary and uses a BACI experimental design to quantify the effect of habitat restoration on the …

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Temperate Eurasian Origins Of Hawaiian Chenopodium (Amaranthaceae) Plus Description Of A New Species Endemic To Moloka‘I, Jason T. Cantley, Angela J. Mcdonnell, J Branson, S R. Long, W Garnett, Christopher T. Martine Jan 2020

Temperate Eurasian Origins Of Hawaiian Chenopodium (Amaranthaceae) Plus Description Of A New Species Endemic To Moloka‘I, Jason T. Cantley, Angela J. Mcdonnell, J Branson, S R. Long, W Garnett, Christopher T. Martine

Faculty Journal Articles

Chenopodium taxa of Hawai‘i are tetraploids distinguished from other members of the circumglobally distributed genus by minute morphological characters. Because of these reasons, the geographic origin of Hawaiian Chenopodium has remained unclear. Across the Hawaiian Archipelago, Chenopodium taxa are morphologically variable and grow in highly disparate xeric habitats, especially in terms of precipitation, temperature, wind, salt spray, and solar irradiation. Habitats include dry subalpine shrublands, sandy beach strand of atolls in the Northwest Hawaiian Islands, dry forests, and precipitously tall sea cliffs of northwestern Moloka‘i. From the Moloka‘i sea cliffs, which are battered by high energy winds, salt spray, and …

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Aquatic Plants And Their Application To Successful Floating Treatment Wetlands, Katherine May Mazanec Jan 2020

Aquatic Plants And Their Application To Successful Floating Treatment Wetlands, Katherine May Mazanec

Masters Theses

“This research aims to mitigate eutrophication of freshwater habitats affected by urban stormwater runoff. Two highly impacted urban ponds near the Missouri S&T campus in Rolla were the focus of this research on the application of floating treatment wetlands (FTWs). An FTW consists of a man-made floating mat that is planted with emergent or floating macrophytes. The plants grow on the mat and their roots extend into the water column below the mat. Plant tissues, especially roots in direct contact with the water, take up nutrients, act as biofilm growth sites, and may facilitate precipitation of nutrients. With urbanization, ponds …

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Abiotic Conditions, Algal Biomass & Fish Growth Rates Affect Fish Mercury Concentrations In Two Subarctic Lakes, Ari Yamaguchi Jan 2020

Abiotic Conditions, Algal Biomass & Fish Growth Rates Affect Fish Mercury Concentrations In Two Subarctic Lakes, Ari Yamaguchi

Theses and Dissertations (Comprehensive)

Kakisa Lake and Tathlina Lake, located in the Dehcho Region of the Northwest Territories, support important fisheries for the local Ka’a’gee Tu First Nation (KTFN). Recently, Walleye (Sander vitreus) of typical catch size in Tathlina Lake were found to have mercury concentrations above Health Canada’s commercial sale guideline of 0.5 ppm. Wild foods with elevated mercury concentrations can pose health risks to the humans who consume them, depending on consumption amounts and vulnerability factors such as age and pregnancy. Because wild fish can accumulate relatively high mercury levels and subsistence fishing contributes greatly to food security in northern …

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Diet Of A Recently Reintroduced River Otter (Lontra Canadensis) Population In Taos County, New Mexico, Gabriela Alexandra Wolf-Gonzalez Jan 2020

Diet Of A Recently Reintroduced River Otter (Lontra Canadensis) Population In Taos County, New Mexico, Gabriela Alexandra Wolf-Gonzalez

Theses and Dissertations--Forestry and Natural Resources

North American river otters (Lontra canadensis), native to every U.S. state and Canada, experienced extensive population decreases and range reduction until the mid-20th century as a result of overexploitation and habitat loss during European colonization. The last known river otter in New Mexico was killed on the Gila River in 1953, although unverified reports continued thru 2008. After a nearly 60-year absence from New Mexico, 33 adult river otters were reintroduced to the Rio Pueblo de Taos in the northern part of the state between 2008-2010; however, they were not subsequently monitored or studied. I characterized diet of …

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Walleye Sander Vitreus Visceral Fat Accumulation, Cole Daleiden, Seth Renner Jan 2020

Walleye Sander Vitreus Visceral Fat Accumulation, Cole Daleiden, Seth Renner

Journal of Earth and Life Science

For ectothermic species, proper lipid retention is critical to surviving in regions with limited growing seasons. Visceral fat is the dominant form of this energy storage in fish. Build up and depletion of these lipids occur seasonally as activity levels change throughout winter and spring. Due to this annual pattern, the purpose of this study is to determine a trend in the amount of visceral fat Walleye Sander vitreus accumulate in a time of year when metabolic rates are low and transition into the spawning process has yet to occur. Angling was the method of capture conducted during the months …

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The Effect Of Seasonality On Yellow Perch Ecology And Ecotoxicology Within Lake Manganese, Bailey Duxbury Jan 2020

The Effect Of Seasonality On Yellow Perch Ecology And Ecotoxicology Within Lake Manganese, Bailey Duxbury

Dissertations, Master's Theses and Master's Reports

Seasonality is a consistent component of aquatic ecosystems yet most fish biological and ecotoxicological studies commonly employ field sampling protocols focused during the warm open water season with minimal emphasis placed on winter sampling, especially for north-temperate latitude ecosystems. Such strategies limit our understanding of poikilotherm biology and ecology during the overwintering seasons. Here, I investigated seasonal changes in yellow perch (Perca flavescens) biology, ecology and ecotoxicology over a one-year period in Lake Manganese. Significant seasonality was observed for metrics including fish energy densities (kJ/g), gonadosomatic indices, whole-body lipid contents, and carbon stable isotope values (δ13C). …

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Extreme Offspring Ornamentation In American Coots Is Favored By Selection Within Families, Not Benefits To Conspecific Brood Parasites, Bruce E. Lyon, Daizaburo Shizuka Jan 2020

Extreme Offspring Ornamentation In American Coots Is Favored By Selection Within Families, Not Benefits To Conspecific Brood Parasites, Bruce E. Lyon, Daizaburo Shizuka

School of Biological Sciences: Faculty Publications

Offspring ornamentation typically occurs in taxa with parental care, suggesting that selection arising from social interactions between parents and offspring may underlie signal evolution. American coot babies are among the most ornamented offspring found in nature, sporting vividly orange-red natal plumage, a bright red beak, and other red parts around the face and pate. Previous plumage manipulation experiments showed that ornamented plumage is favored by strong parental choice for chicks with more extreme ornamentation but left unresolved the question as to why parents show the preference. Here we explore natural patterns of variation in coot chick plumage color, both within …

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Gulf Coast Marine Laboratories Past, Present And Future, Donald F. Boesch Jan 2020

Gulf Coast Marine Laboratories Past, Present And Future, Donald F. Boesch

Gulf and Caribbean Research

I spent my nearly 50—year career in marine science working at marine laboratories, most of that as a chief executive officer. So, it is appropriate that my reflections are about marine laboratories, rather than my own science. After relating my career course, I turn my attention to the history and development of marine laboratories along the U.S. coast of the Gulf of Mexico (GOM). Surprisingly, the region’s first laboratory was actually constructed in 1903 at Cameron, LA, but operated less than a decade before closing. It was not until after World War II that the university—affiliated marine laboratories of today …

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Spatial And Temporal Genetic Structure Of Winter-Run Steelhead (Oncorhynchus Mykiss) Returning To The Mad River, California, Steven R. Fong Jan 2020

Spatial And Temporal Genetic Structure Of Winter-Run Steelhead (Oncorhynchus Mykiss) Returning To The Mad River, California, Steven R. Fong

Cal Poly Humboldt theses and projects

Distinct populations of steelhead in the wild are in decline. The propagation of steelhead in hatcheries has been used to boost population numbers for recreational fisheries and for use in conservation. However, hatchery breeding practices of steelhead can result in changes in genetic structure. I investigated the genetic structure of winter-run steelhead (Oncorhynchus mykiss) returning to the Mad River, California, where a hatchery has been used enhance production for recreational fisheries since 1971. Genetic variability in Mad River steelhead was evaluated using 96 single nucleotide polymorphisms (SNPs) among 4203 individuals, including the Mad River and nearby locations, and …

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Changes In Prey Mortality: The Efects Of Multiple Predators And Temperature On California Mussels, Wesley Hull Jan 2020

Changes In Prey Mortality: The Efects Of Multiple Predators And Temperature On California Mussels, Wesley Hull

Cal Poly Humboldt theses and projects

Organisms serve as prey to a variety of predators within natural systems, detecting threats through physical and chemical means. While predator feeding behavior is also affected by the presence of other predators, it is unclear whether differing modes of detection have similar effects on predator feeding behavior. In rocky intertidal zones in northern California, the California mussel (Mytilus californianus) is a competitively dominant foundation species consumed by a variety of predators. I quantified the individual and combined effects of ochre star (Pisaster ochraceus) and rock crab (Romaleon antennarium) predation on mussels by implementing mussel …

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Impacts Of Transportation Infrastructure On Water Quality, Sediment Loads, And Fishing Opportunities In The Gwich’In Settlement Area, Northwest Territories, Matthew Teillet Jan 2020

Impacts Of Transportation Infrastructure On Water Quality, Sediment Loads, And Fishing Opportunities In The Gwich’In Settlement Area, Northwest Territories, Matthew Teillet

Theses and Dissertations (Comprehensive)

The addition of gravel sediment to build ferry landings on the Peel and Mackenzie Rivers has been an ongoing concern for the Gwich’in communities of Fort McPherson and Tsiigehtchic that depend on the rivers for their livelihoods. Specifically, there are concerns that gravel from ferry landings is degrading water quality, harming fishing opportunities, and altering river morphology downstream. Previous reports concluded that ferry operations were not impacting downstream ecology. However, past studies had methodological shortcomings and community concerns about the ferry landings remain. To study the impact of the gravel landings on water quality, I utilized a multidisciplinary study design …

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