Population Biology Commons^™

Size Structure Of Black Crappie And Bluegill In Northern, Eastern, Western, And Southern Minnesota, Ray Anderson

Journal of Earth and Life Science

Fish size structure is an important factor in a fishery population. Panfish such as black crappie Pomoxis nigromaculatus and bluegill Lepomis macrochirus play a major role in the health of fisheries. Five lakes from southern, northern, eastern, and western Minnesota were selected for analysis. Data were collected using standard sampling methods, including gill nets, electrofishing, and fyke nets. Length-frequency distributions were created to assess size structure in each region. Relative abundance was measured using catch per unit effort. Data analysis included a one-way ANOVA to compare Proportional Size Distribution (PSD) values and the distribution of fish sizes among regions. Chi-square …

Comparison Of Hoop Nets To Trap Nets In Sampling Panfish, Jayden R, Alsleben

Journal of Earth and Life Science

Panfish including bluegill Lepomis macrochirus and black crappie Pomoxis nigromaculatus are gamefish species of significance found in Minnesota. Hoop nets and trap nets are two types of gear that can be used to sample these fish. Fisheries managers and anglers alike are interested in the best tactics to capture panfish. The behavior of fish, including bluegill and black crappie, change throughout the sampling season and make it difficult to assume accurate representations. Trap nets have historically been adequate in sampling near shore populations, but questions surrounding the gear have allowed other options to be pursued. The objective of this study …

A Sample Of Fish Communities In Beaver Ponds Of Northern Minnesota, Reed Cumberland, Rose Kuhlmann

Journal of Earth and Life Science

The North American beaver Castor canadensis is an ecosystem engineer and a keystone species to the environment. Beaver inhabit ponds and construct dams to build ponds that provide habitat for certain fish. Little information is provided on the species of fish that live in beaver ponds. The objective of this study is to sample the fish communities in beaver ponds while comparing the effectiveness of two styles of minnow traps. Twelve beaver ponds were selected in the Bemidji area to be sampled. The quantity and species caught in each style of trap were recorded to compare effectiveness of each trap …

Does Depth Affect Zebra Mussel Length In Scalp Lake?, Zanden Mellen

Journal of Earth and Life Science

Since its first sighting in 1996, zebra mussels Dreissena polymorpha have been confirmed in hundreds of Minnesota lakes. Not only were they found in lakes, but they are also found in rivers too. With lack of effective treatments to impede their spread, zebra mussels continue to colonize new areas causing ecological as well as economic harm. The objective of this study was to see if there was a relationship between a zebra mussel length and the depth, they are found using shell length (mm) and depth (cm). The comparison of zebra mussel length and depth was done by performing a …

Age Class Is Not Related To Size Or Composition Of Home Ranges Among Suburban White-Tailed Deer During Parturition, Nathan D. Pyburn

Journal of Earth and Life Science

How white-tailed deer use the landscape in an urban environment can help us understand the effects of urbanization on deer populations. White-tailed deer form observable matriarchal hierarchies in studied populations. This study examines the matriarchal structure, home range size, and home range composition of 25 collared white-tailed deer within the city limits of Bemidji, MN. The results found no significant difference between age class and home range size or composition. However, movement metrics from yearling and mature age classes were more similar than the juvenile age class females. I propose this is because social acceptance between mature females was higher …

Bat Species Diversity In The Klamath Basin Prior To Dam Removals, Ryan Page Matilton

Cal Poly Humboldt theses and projects

River ecosystems make up a small percentage of the earth’s surface, but they support high levels of biodiversity and attract high levels of human use. Dams, for example, disrupt a river’s natural course and flow, alter water temperatures in the stream, redirect river channels, transform floodplains, and fragment river continuity, which affects ecological balance and food webs. The Klamath River in northern California, which has been dammed for the last century, experienced dramatic disruptions including a large fish die-off in 2002. With the negative impacts of the Klamath dams apparent, multiple entities negotiated to remove the dams and restore the …

Group And State-Specific Estimation In Animal Movement Models Using A Bayesian Approach, Anita Bhandari Sharma

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This research study investigates statistical approaches for modeling the movement patterns of white-tailed deer in Louisiana using GPS tracking data. We start by classifying the latent behavioral states using a hidden Markov model (HMM) and then integrate those inferred states into a state-dependent step selection framework to evaluate the land cover preferences. Standard HMMs, however, assume the same movement patterns for all animals, overlooking the differences due to characteristics such as sex, age, breeding season, etc.

To address this limitation, we extend the modeling framework to incorporate the group-level structure defined by similar characteristics or conditions to assess whether such …

Ina Scuba: Mobilization Of French West Indies Scuba Diving Clubs To Rapidly Improve Knowledge On Threatened Marine Species. Case Of The White-Spotted Eagle Ray (Aetobatus Narinari)., Océane Beaufort, Rocio Prieto González

Gulf and Caribbean Research

The White—Spotted Eagle Ray (Aetobatus narinari), listed as Endangered on the IUCN Red List since 2021, is experiencing alarming population declines, underscoring the urgent need for targeted conservation efforts. This species, which plays a vital ecological role in marine food webs, has biological and ecological characteristics that make it particularly vulnerable to habitat degradation and anthropogenic pressures, particularly fishing, tourism, and maritime traffic. In the French West Indies (FWI), the paucity of data on the White—Spotted Eagle Ray remains a major obstacle to the development of effective, island—specific conservation strategies. To address this gap, the INA Scuba participatory …

Oyster Horizons: Spatial Prioritization For Oyster Restoration At Alabama Living Shorelines, Trinity Henry-Jack, Aaron Bland, Christa Russell, Ronald Baker

Gulf and Caribbean Research

No abstract provided.

Macroinvertebrate Community Dynamics In A Recovering, Hypersaline Estuary, Catherine M. Eckert, Claudia A. Tamez, Erin E. Easton, David W. Hicks

Gulf and Caribbean Research

The Bahia Grande is a 6,500—acre tidal basin located at the southernmost tip of Texas. Tidal flow into this coastal estuary was cut off in the 1930s, causing the basin to dry up for ~70 y. A pilot channel connecting the Bahia Grande to tidal waters was constructed in 2005, allowing flooding of the basin to occur. Throughout the period reported herein (2005–2019), the system remained characterized by persistent spatial and temporal episodes of extreme hypersalinity (>70)—a critical factor influencing estuarine community composition and driving key ecological processes. With additional rehabilitation actions forthcoming, characterization of the estuary is essential …

Predicting Capture And Survival Probabilities Of The Arizona Tiger Salamander: A Comparison Of Capture-Recapture Models, Brittney Nelson

Murray State Theses and Dissertations

Capture-recapture models are essential tools for estimating population dynamics in ecological studies. A fundamental component of these models is the capture history matrix, which records individual detection over time and serves as the basis for estimating survival and capture probabilities. This presentation explores three statistical approaches to these estimations: the Cormack-Jolly-Seber (CJS) model, the Hidden Markov Model (HMM) for CJS, and the Bayesian CJS model. The CJS model provides a likelihood-based framework for estimation, and the HMM CJS incorporates latent states into the model to account for uncertainty in detection. The Bayesian CJS extends this same analysis by integrating prior …

Assessing The Effects Of Wildfire Season Pm2.5 Exposure And Environmental Variables On Breeding Season Avian Body Condition, Cira Seyer-Ochi

Scripps Senior Theses

The increasing frequency and intensity of wildfires pose growing threats to wildlife, yet the indirect effects of wildfire smoke on avian populations remain largely unstudied. This exploratory study provides an initial assessment of how particulate matter 2.5 (PM2.5) associated with smoke pollution from the 2017 California wildfire season, in conjunction with precipitation and habitat type, influences the body condition of four resident bird species during the 2018 breeding season. Using bird banding data from 29 Monitoring Avian Productivity and Survivorship (MAPS) stations, I assessed the potential interactions between PM2.5 concentrations, precipitation, and habitat type with body condition for Song Sparrows …

Jaguar (Panthera Onca) Population Status And Conservation Needs In Panama Revealed Using Spatial Density And Occupancy Models., Rebeca E. Becdach

Cal Poly Humboldt theses and projects

Jaguars (Panthera onca) are key predators and the largest felid in the Americas. The species is listed as near threatened globally due to habitat loss, fragmentation, and human persecution. Their population decline can negatively affect the structure and functioning of the ecosystems they inhabit. Conservation efforts for jaguars and their habitat require understanding jaguar populations and how they are impacted by human presence across their range. This information is lacking in Panama, a critical portion of the Jaguar range. Panama forms a narrow land bridge connecting Central and South America, integral to wildlife movement, including jaguars, across both …

Just Keep Swimming: Outmigration Survival Of Upper Klamath Basin Juvenile Chinook Salmon, James M. Whelan

Cal Poly Humboldt theses and projects

The removal of four impassable hydroelectric dams on the Klamath River provides salmonids with the opportunity to recolonize their historic range in the upper Klamath River watershed. However, successful reestablishment of salmon populations requires juvenile salmon born in Oregon's upper tributaries to safely migrate downstream through the river's upper reaches. This stretch of the Klamath River, immediately downstream of Upper Klamath Lake, presents multiple migration challenges, including two flow-control dams not scheduled for removal (Link River Dam and Keno Dam), significant water diversions, and water quality issues. To evaluate these challenges, I conducted experimental releases of radio-tagged juvenile Chinook salmon …

Cost-Effective Strategies For Feral Swine Control: Exploring Trapping Equipment Cooperatives, Phil Kenkel, Riza Radmehr, Rodney Holcomb, Mckenzie Boyce

Human–Wildlife Interactions

Feral swine (Sus scrofa) in the United States have become a growing concern, with a population of ≥6 million and causing annual damages of ≥$1.5 billion USD. Because of their high reproductive capacity, effective control methods are crucial to reducing or slowing their population growth. While remotely monitored and triggered traps have proven to be an effective control strategy, the cost of sophisticated trapping equipment, which can cost ≥$7,000 USD, is often cost prohibitive for many landowners. Despite the pressing need to address the challenge of making effective feral swine control methods more affordable, there are few studies …

Exploring Coastal Plain Fish Ecology Across A Range Of Early-Life-History Traits And River Types, Bridgette Nicolosi

College of Graduate Studies: Theses & Dissertations

The ecological complexity of southeastern Coastal Plain rivers is reflected in the diversity of fish communities they support, yet the processes structuring early life dynamics remain poorly understood. This thesis explores the influence of environmental gradients on larval fish assemblage composition and American Shad (Alosa sapidissima) spawning phenology across two Georgia Coastal Plain river systems.

In the unregulated Ogeechee River, I investigated spatial and temporal variation in larval fish communities by comparing mainstem and tributary habitats to understand the role of tributaries in watershed-wide larval production. Larvae were collected biweekly from May to September 2024 at eight paired mainstem-tributary sites …

Tailwater Trout Population Dynamics, Connor Dylan Cunningham

Graduate Theses/Dissertations

Dams have been constructed throughout the world and provide several resources for humans (e.g., flood control, hydropower). These structures heavily alter the upstream and downstream environment. One consequence of these alterations is the creation of “tailwaters”, which can create cold-water habitat via hypolimnetic releases. In the southeast United States these tailwater environments are often managed for the recreational use of nonnative salmonids. The unnatural flow regimes of tailwaters affect the biotic and abiotic conditions and ultimately the dynamic rate functions (i.e., recruitment, growth, mortality) of the fish inhabiting them. As such, the goal of this research is to provide fisheries …

Acer Rubrum: Descending Towards Forest Dominance, Elyssa L. Pearson, Christopher M. Gough

Undergraduate Research Posters

Acer rubrum, more commonly known as the red maple, is a hardwood, late successional species of tree commonly planted for its deciduous nature and vibrant coloring of its leaves in the beginning of autumn (Abrams, 1998). The species is very tolerant of varying light and soil moisture levels and often dominates sub and mid-canopy levels of hardwood forests (Missouri Botanical Gardens). It was hypothesized that as the I moved from an upland location to a lowland location near a wetland that the A. rubrum trees would be more productive and have a greater above ground biomass. This was not …

Better Together: Leveraging Existing Research To Evaluate Population Trends, Habitat Selection, And Species Interactions Of Mesocarnivores, Jordan Lee Heiman

Graduate Student Theses, Dissertations, & Professional Papers

Whether from human impacts, climate change, or extreme fires, landscapes around the world are rapidly changing (Foley et al. 2005, Grimm et al. 2008, Bowman et al. 2020). As these landscapes change, it is clear that many ecosystems and species are being negatively affected (Laliberte and Ripple 2004, Butchart et al. 2010, Freeman et al. 2018, Li et al. 2022). With an expanding number of species facing extinction risks, it is critical for agencies to know when and where to focus their limited resources and conservation efforts (Martin et al. 2012, Auerbach et al. 2014, Bal et al. 2018). To …

Divergent Floral And Vegetative Trait Responses To Abiotic Factors Drive Phenotypic Diversity In Platanthera Dilatata (Orchidaceae) Across Alaska, Marlin L. Bowles, Lisa E. Wallace

Biological Sciences Faculty Publications

Multiple traits make up an integrated phenotype, but traits may be shaped by differing drivers. It is often assumed that selection by biotic agents drives floral variation, but abiotic factors are also known to influence floral traits. Understanding trait covariations and their association with diverse environmental factors is a central question in evolution and ecology. Here, we studied covariation in floral and vegetative traits in relation to climate and topo-edaphic variation in the orchid Platanthera dilatata. In Platanthera, nectar spur length is associated with pollinator tongue length, but much variation exists in other traits too, likely to be …