Population Biology Commons^™

Understory Arthropod Diversity In A Mixed Dryland Ecosystem, Hawai‘I, Matthew J. Madeiros, William P. Haines, Clare E. Aslan, Aaron B. Shiels, Asa Aue, Christina T. Liang

United States Department of Agriculture Wildlife Services: Staff Publications

Tropical drylands are among the most threatened ecosystems worldwide, and fewer than 10% of tropical dry forests in Hawai‘i remain intact. Terrestrial arthropods comprise most of the endemic fauna on many islands, including Hawai‘i, where they provide ecosystem services such as pollination, decomposition, and a reliable prey base for predators. The objective of our study was to measure understory arthropod diversity and relative abundances in two common habitat types within dryland Hawai‘i—a non-native grassland, dominated by Cenchrus setaceus (fountain grass) with few native shrubs, and a native woodland, dominated by Metrosideros polymorpha (‘ōhi‘a). We used generalized additive models to examine …

Evaluation Of Roost Culling As A Management Strategy For Reducing Invasive Rose‑Ringed Parakeet (Psittacula Krameri) Populations, C. Janes Anderson, Leonard A. Brennan, William P. Bukoski, Steven C. Hess, Clayton D. Hilton, Aaron B. Shiels, Shane Siers, Bryan M. Kluever, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Rose-ringed parakeets (Psittacula krameri) are one of the most widespread invasive avian species worldwide. This species was introduced to the island of Kaua‘i, Hawai‘i, USA, in the 1960s. The rapidly increasing population has caused substantial economic losses in the agricultural and tourism industries. We evaluated the efficacy of a roost culling program conducted by an independent contractor from March 2020 to March 2021. We estimated island-wide minimum abundance was 10,512 parakeets in January 2020 and 7,372 in April 2021. Over 30 nights of culling at four roost sites, approximately 6,030 parakeets were removed via air rifles with 4,415 …

Social Network Analysis Of White-Tailed Deer Scraping Behavior: Implications For Disease Transmission, Michael E. Egan, Kim M. Pepin, Justin Fischer, Scott R. Hygnstrom, Kurt C. Vercauteren, Guillaume Bastille-Rousseau

United States Department of Agriculture Wildlife Services: Staff Publications

Host contact structure affects pathogen transmission in host populations, but many measures of host contact do not distinguish contacts that are relevant to pathogen transmission from those that are not. Scrapes are sites for chemical communication by white-tailed deer (Odocoileus virginianus) during the breeding season and potential sites of transmission of prions, the causative agent of chronic wasting disease (CWD). Scrape-related behaviors vary in their probability of transmitting prions to or from the environment, suggesting that behavior be combined with contact structure to better reflect potential heterogeneity in prion transmission at scrapes. We recorded visits and behaviors by …

Disease Progression And Serological Assay Performance In Heritage Breed Pigs Following Brucella Suis Experimental Challenge As A Model For Naturally Infected Feral Swine, Vienna R. Brown, Ryan S. Miller, Courtney F. Bowden, Timothy J. Smyser, Nicholas A. Ledesma, Aim E. Hartwig, Paul Gordy, Aaron M. Anderson, Stephanie M. Porter, Kate Alexander, Zane Gouker, Tom Gidlewski, Richard A. Bowen, Angela M. Bosco-Lauth

United States Department of Agriculture Wildlife Services: Staff Publications

Invasive feral swine (Sus scrofa) are one of the most important wildlife species for disease surveillance in the United States, serving as a reservoir for various diseases of concern for the health of humans and domestic animals. Brucella suis, the causative agent of swine brucellosis, is one such pathogen carried and transmitted by feral swine. Serology assays are the preferred field diagnostic for B. suis infection, as whole blood can be readily collected and antibodies are highly stable. However, serological assays frequently have lower sensitivity and specificity, and few studies have validated serological assays for B. suis in feral swine. …

Evaluation Of The Effect Of Hydrated Lime On The Scavenging Of Feral Swine (Sus Scrofa) Carcasses And Implications For Managing Carcass-Based Transmission Of African Swine Fever Virus, Courtney F. Bowden, James Grinolds, Gregory Franckowiak, Loma Mccallister, Joe M. Halseth, Matthew Cleland, Travis Guerrant, Michael J. Bodenchuk, Robert Miknis, Michael C. Marlow, Vienna R. Brown

United States Department of Agriculture Wildlife Services: Staff Publications

African swine fever (ASF) is a devastating hemorrhagic disease marked by extensive morbidity and mortality in infected swine. The recent global movement of African swine fever virus (ASFV) in domestic and wild swine (Sus scrofa) populations has initiated preparedness and response planning activities within many ASF-free countries. Within the US, feral swine are of utmost concern because they are susceptible to infection, are wide-spread, and are known to interact with domestic swine populations. African swine fever virus is particularly hardy and can remain viable in contaminated carcasses for weeks to months; therefore, carcass-based transmission plays an important role in the …

Perturbations Highlight Importance Of Social History In Parakeet Rank Dynamics, Annemarie Van Der Marel, Xavier Francis, Claire L. O'Connell, Cesar O. Estien, Chelsea Carminito, Virginia Darby Moore, Nickolas Lormand, Bryan M. Kluever, Elizabeth A. Hobson

United States Department of Agriculture Wildlife Services: Staff Publications

Dominance hierarchies can provide many benefits to individuals, such as access to resources or mates, depending on their ranks. In some species, rank can emerge as a product of a group’s history of social interactions. However, it can be difficult to determine whether social history is critical to rank in observation-based studies. Here, we investigated rank dynamics in three captive groups of monk parakeets (Myiopsitta monachus). We used experimental social perturbations to test whether social history shapes rank emergence in these groups. Using targeted removals and reintroductions, we tested whether differently ranked individuals could re-take their ranks in hierarchies after …

Distribution Of The Misfolded Isoform Of The Prion Protein In Peripheral Tissues And Spinal Cord Of Rocky Mountain Elk (Cervus Elaphus Nelsoni) With Naturally Occurring Chronic Wasting Disease, Terry R. Spraker, Thomas Gidlewski, J. G. Powers, T. A. Nichols, M. A. Wild

United States Department of Agriculture Wildlife Services: Staff Publications

Chronic wasting disease (CWD) is an infectious transmissible spongiform encephalopathy of cervids associated with the presence of a misfolded prion protein (PrPCWD). Progression of PrPCWD distribution has been described using immunohistochemistry and histologic changes in a single section of brain stem at the level of the obex resulting in scores from 0 (early) to 10 (terminal) in elk with naturally occurring CWD. Here we describe the spread and distribution of PrPCWD in peripheral tissues and spinal cord in 16 wild and 17 farmed Rocky Mountain elk (Cervus elaphus nelsoni) with naturally occurring CWD and correlate these findings with obex scores. …

Predator Telemetry Informs Temporal And Spatial Overlap With Stocked Salmonids In Lake Huron, David G. Fielder, Todd A. Hayden, Thomas R. Binder, Brian S. Dorr, Heidi A. Currier

United States Department of Agriculture Wildlife Services: Staff Publications

Double-Crested Cormorants (Phalacrocorax auratus), Walleyes (Sander vitreus), and Lake Trout (Salvelinus namaycush) are migratory predators that undergo extensive movements in Lake Huron. Stocking of juvenile salmonid fish (Oncorhynchus and Salmo sp.) is an important component of fishery management in Lake Huron and assessing the spatial and temporal extent of predator movements is a useful consideration for determining when and where to stock juvenile fish to reduce predation and maximize survival. Previous investigation indicated that some Walleyes migrate to the main basin of Lake Huron in spring from Saginaw Bay. Similarly, telemetry studies of Lake Trout movement in Lake Huron have …

Role Of Social Structure In Establishment Of An Invasive Large Mammal After Translocation, Lindsay M. Clontz, Anni Yang, Sarah M. Chinn, Kim M. Pepin, Kurt C. Vercauterten, George Wittemyer, Ryan S. Miller, James C. Beasley

United States Department of Agriculture Wildlife Services: Staff Publications

Background

Data on the movement behavior of translocated wild pigs is needed to develop appropriate response strategies for containing and eliminating new source populations following translocation events. We conducted experimental trials to compare the home range establishment and space-use metrics, including the number of days and distance traveled before becoming range residents, for wild pigs translocated with their social group and individually.

Results

We found wild pigs translocated with their social group made less extensive movements away from the release location and established a stable home range ~5 days faster than those translocated individually. We also examined how habitat quality …

Quantitative Song Variety In Relation To Genotype In A Hybridizing Chickadee Population, Shelby Madison Palmer

Graduate Theses/Dissertations

The Black-capped chickadee (Poecile atricapillus) and Carolina chickadee (P. carolinensis) are North American songbird species that hybridize in a narrow contact zone stretching latitudinally from New Jersey to Kansas, USA. The association between genetic ancestry and song type in this hybrid zone has been studied independently several times and found to be minimal or absent, likely due to the influence of cultural transmission on learned song in the oscine passerine clade to which the chickadees belong. Despite this, the song of both species remains remarkably distinct in allopatry, suggesting a genetic constraint on certain qualities of …

Riverine Fish Population Dynamics, Aaron P. Muehler

Graduate Theses/Dissertations

Dynamic rate functions (i.e., recruitment, growth, mortality) structure fish populations and are subject to latitudinal differences. These latitudinal differences are likely reflective of climatic variation and may result in spatially distinct populations that must be managed independently, especially in large systems such as the Upper Mississippi River system (UMRS). In order to successfully manage this system, an understanding of what drives these populations is required. The UMRS is useful for this investigation as it crosses 10° temperate latitude with widespread fish species found throughout. In this study, I investigated the synergistic relationship between latitude, vital rates, and abundance. Species were …

The Role Of Interspecific Competition In The Range Collapse Of A Songbird After Rapid Range Expansion, Zachary H. Vickers

Graduate Theses/Dissertations

There is a wealth of evidence demonstrating interspecific competition in birds, but often this evidence is localized and may or may not entirely explain range dynamics over large geographic extents. Bewick’s Wrens (Thrymanes bewickii) and House Wrens (Troglodytes aedon) are small passerine birds of the family Troglodytidae. Previous experimental evidence has demonstrated that Bewick’s Wrens suffer from asymmetric interference competition from House Wrens in Kansas, and this evidence has been cited as the likely reason for the historically recent range collapse of the Bewick’s Wren. However, I argue that localized experimental evidence is insufficient to explain abundance trends over large …

Interspecific Oral Rabies Vaccine Bait Competition In The Southeast United States, Wesley C. Dixon, Jacob E. Hill, Richard Chipman, Amy J. Davis, Amy Gilbert, James C. Beasley, Olin E. Rhodes Jr., Guha Dharmarajan

United States Department of Agriculture Wildlife Services: Staff Publications

The United States Department of Agriculture’s National Rabies Management Program (NRMP) has coordinated the use of oral rabies vaccination (ORV) to control the spread of raccoon rabies virus variant west of the Appalachian Mountains since 1997. Working with state and local partners, the NRMP deploys ORV baits containing a rabies vaccine, primarily targeting raccoon populations (Procyon lotor). Bait competition between raccoons and non-target species may limit the effectiveness of ORV programs, but the extent of bait competition remains poorly quantified, particularly in the southeastern United States. We placed placebo ORV baits in bottomland hardwood (n = 637 baits) and upland …

Insights Into The Conservation Of The Rare Perennial Herb, Astragalus Applegatei, Sean Stewart

Cal Poly Humboldt theses and projects

As anthropogenic activities expand, conservation of rare and endangered species is critical to reduce extinction risks. Collecting and analyzing demographic data can assist in the development of conservation strategies and can help evaluate the success of existing strategies. In this study, I built integral projection models from five years of demographic data and conducted a population viability analysis on four populations of the rare perennial herb, Astragalus applegatei, to inform conservation decisions. I also assessed how planting A. applegatei seedlings might contribute to the growth of an extant population. I found that one population was already below the extinction …

History, Annotated Gazetteer, And Bibliography Of Sarawak Ornithology, Frederick H. Sheldon, Dency F. Gawain, Daisy G. S. Kho, Rosalina Regai, Subir B. Shakya, Chin Aik Yeap

Occasional Papers of the Museum of Natural Science, Louisiana State University

Sarawak is Malaysia’s largest state, covering most of northern Borneo. It has a remarkable history of scientific bird study, starting in the 1840s and growing ever since. To set the stage for the gazetteer, which is the core of this paper, we start with a review of this history and discuss various forces that have influenced the direction of bird research in the state. Following this introduction comes the gazetteer, which is an annotated list of c. 865 sites in Sarawak where birds have been collected, studied, or regularly observed. The gazetteer provides the latitude, longitude, and elevation of each …

Differences In Drifting Invertebrate Communities Across Arctic Ecozones And The Influence On Potential Growth Of Grayling (Thymallus Arcticus), Charles Chanyi

Theses and Dissertations (Comprehensive)

Invertebrate drift is a key process that potentially affects multiple levels of food web organization within stream environments. However, our understanding of the mechanistic drivers of drift in high latitude streams and subsequent bottom-up control that drift may have on fish predators in these environments remains understudied. This project aimed to gain the baseline knowledge of how drift functions across two major high latitude ecozones, the boreal forest and tundra, and how those possible differences in drifting community characteristics may impact drift-feeding Arctic grayling (Thymallus arcticus). These objectives were accomplished by characterizing stream environments across both ecozones, sampling …

Comparing Fish Species Assemblage Between Impacted And Restored Estuarine Salt Marshes Within The Eel River Estuary, Humboldt Co. Ca, Adam Aguilar, Isaac Basham-Clair, Tristan F. Parkinson, Larkin C. Wells

Undergraduate Scholarship

This report details a study assessing the fish assemblages of a recently restored estuarine salt marsh site, and a similar unrestored and impacted site along the Eel River estuary. These two sites are located within the Eel River (Wiya’t) estuary, roughly 10 miles west of the city of Fortuna, CA. This study was conducted during the months of September through October 2023. Data collection was done through seine net dragging at randomly selected sample points across both sites. Seine net hauls were recorded by species and species count, which were later computed using a diversity index to provide values representative …

A Preliminary Assessment Of The Spawning Potential Ratio Of Five Target Species Of The Coastal Gillnet Fishery In Guyana And Suriname, Tomas Willems, Elford Liverpool, Michael Hiwat

Gulf and Caribbean Research

Data—limited stock assessment methods have the potential to positively impact livelihoods of fishermen around the world by providing management recommendations that aim to optimize sustainable yields from fisheries. Some years ago, a novel length— based (LB) method was developed for the assessment of spawning potential ratio (SPR), a measure of the reproductive capacity of fish stocks. We applied the LB—SPR method to 5 important target species of the coastal gillnet fishery in Guyana and Suriname. Nebris microps (Smalleye Croaker; 32% SPR) and Macrodon ancylodon (King Weakfish; 34% SPR) had the highest spawning potential, but remained below the 40% target level …

What Kills The Virtually Immortal Palms Of The Florida Scrub?, Warren G. Abrahamson Ii

Faculty Journal Articles

Premise: Life span varies greatly across plants, with some species being capable of extreme longevity. Yet even long‐lived individuals are susceptible to climatic events, fire, and other challenges. We examined rare mortality events and their causes in two long‐lived palmettos over four decades. Methods: We monitored the survival of the clonal Serenoa repens and non‐clonal, Florida‐endemic Sabal etonia from 1981 to 2022 in four habitats along an elevational gradient within the globally imperiled Florida scrub ecosystem. We considered several challenges to palmetto survival, including extreme fires, shading due to lack of fire, droughts, periods of high precipitation, and possible pathogens. …

Quantifying Antarctic Krill Connectivity Across The West Antarctic Peninsula And Its Role In Large-Scale Pygoscelis Penguin Population Dynamics, Katherine L. Gallagher, Michael S. Dinniman, Heather J. Lynch

CCPO Publications

Antarctic krill (Euphausia superba) are considered a keystone species for higher trophic level predators along the West Antarctic Peninsula (WAP) during the austral summer. The connectivity of krill may play a critical role in predator biogeography, especially for central-place foragers such as the Pygoscelis spp. penguins that breed along the WAP during the austral summer. Antarctic krill are also heavily fished commercially; therefore, understanding population connectivity of krill is critical to effective management. Here, we used a physical ocean model to examine adult krill connectivity in this region using simulated krill with realistic diel vertical migration behaviors across …