Population Biology Commons^™

Census And Mapping Of Chorro Creek Bog Thistle In Reservoir Canyon, San Luis Obispo, Ca, Tyler Michael Lutz

Biological Sciences

Chorro Creek bog thistle (Cirsium fontinale var. obispoense) is a federally endangered variety of Fountain thistle endemic to western San Luis Obispo County. The U.S. Fish and Wildlife Service knows of nineteen populations, many with multiple colonies. A population was discovered in the Reservoir Canyon Natural Reserve in 2001, but has not been monitored or described since the time of its discovery. In fall of 2013, a census of the population was performed, the four colonies were mapped, and a floristic survey was conducted. A field experiment was initiated to determine if reducing the riparian canopy coverage can …

A Seasonal, Density-Dependent Model For The Management Of An Invasive Weed, Esther Shyu, Eleanor A. Pardini, Tiffany M. Knight, Hal Caswell

Biology Faculty Publications & Presentations

The population effects of harvest depend on complex interactions between density dependence, seasonality, stage structure, and management timing. Here we present a periodic nonlinear matrix population model that incorporates seasonal density dependence with stage-selective and seasonally selective harvest. To this model, we apply newly developed perturbation analyses to determine how population densities respond to changes in harvest and demographic parameters. We use the model to examine the effects of popular control strategies and demographic perturbations on the invasive weed garlic mustard (Alliaria petiolata). We find that seasonality is a major factor in harvest outcomes, because population dynamics may …

Population Demographics And Genetic Structure Of Black Bears In Coastal Louisiana, Jesse Charles Troxler

Masters Theses

The range and abundance of the Louisiana black bear (Ursus americanus luteolus) were greatly diminished during the 20th century. This subspecies was reduced to 3 small, isolated subpopulations in Louisiana as bottomland hardwood habitat was converted to agriculture. These bears were listed as threatened by the U.S. Fish and Wildlife Service in 1992 and a recovery plan was published in 1995. Recovery requires estimates of population parameters to evaluate current population status and future viability. I conducted a mark-recapture study from 2010 to 2012 to estimate demographic parameters of the coastal population of Louisiana black bears. Because inbreeding …

Body Size Variation In Two Adjacent Populations Of Black Kingsnakes (Lampropeltis Nigra) In East Tennessee, Jesse Weber, Joshua Ennen

Chancellor’s Honors Program Projects

No abstract provided.

The Tadpole Of Leptodactylus Caatingae Heyer & Juncá, 2003 (Anura: Leptodactylidae): External Morphology, Internal Anatomy, And Natural History, Felipe De Madeiros Magalhães, Adrian Antonio Garda, Ralita Ferreira Amado, Rafael O. De Sá

Biology Faculty Publications

We describe and illustrate the external morphology, oral disc, chondrocranium, and internal oral anatomy of Leptodactylus caatingae larvae. We analyze the internal oral anatomy using scanning electron microscopy of a larva in Gosner, stage 38 and chondrocranial anatomy is reported for Gosner stage 34. The tadpole at Gosner stage 38 has a globular body shape with low tail fins and a ventral oral disc bordered by two rows of marginal papillae on most of the disc, except for the anterior labium and a medial portion of the posterior labium where papillae are simple; a wide rostral gap is present, labial …

The Genus Odontophrynus (Anura: Odontophrynidae): A Larval Perspective, Filipe Augusto C. Do Nascimento, Tamí Mott, José A. Langone, Christine A. Davis, Rafael O. De Sá

Biology Faculty Publications

The genus Odontophrynus consists of 11 species of medium-sized frogs distributed across south and east South America. This study examines and describes the chondrocrania and oral cavities of 0. americanus, 0. maisuma, 0. carvalhoi, and 0. cu/tripes, and reviews current knowledge about the larval external morphology of the genus. Twenty-one tadpoles were cleared and double-stained for chondrocranium description and five tadpoles were dissected for analysis in a scanning electron microscope. The presence of a tectum parientale may be considered here as a putative synapomorphy of the genus. The 0. americanus and 0. cu/tripes species groups were partially differentiated by the …

Jellyfish Identification And Quantification In The San Francisco Estuary, Amalia Borson, Lindsay L. Sullivan, Wim Kimmerer

STAR Program Research Presentations

As potential predators and competitors of plankton-eating fish, jellyfish have the potential to negatively impact fish populations. Jellyfish were collected weekly with plankton tows from the RombergTiburonCenterpier in Tiburon, CA. Since some jellyfish were too small to identify, one tow was collected and preserved to record abundances, and a second tow was collected to rear jellyfish until distinguishing characteristics were visible enough for identification. Jellyfish in the preserved tows were then identified, measured, and counted, and their abundance (number m^-3) was calculated. Jellyfish from the second tows were reared in plastic buckets that were lightly bubbled using aquarium …

Reproductive Isolation And Cryptic Introgression In A Sky Island Enclave Of Appalachian Birds, Gene D. Sattler, Michael J. Braun

Faculty Publications and Presentations

Reproductive isolation is central to the speciation process, and cases where the strength of reproductive isolation varies geographically can inform our understanding of speciation mechanisms. Although generally treated as separate species, Black-capped chickadees (Poecile atricapillus) and Carolina chickadees (P. carolinensis) hybridize and undergo genetic introgression in many areas where they come into contact across the eastern United States and in the northern Appalachian Mountains. The Great Smoky Mountains harbor the last large breeding population of atricapillus in the southern Appalachians, isolated from the species’ main range by nearly 200 km. This population is believed to be reproductively isolated from local …

Trends In Borrelia Spp. Prevalence In Ixodes Spp. Ticks From The Southeastern Coastal United States, Lauren Paul Maestas

Masters Theses

The Lyme borreliosis (LB) cycle, involving Ixodes scapularis and Borrelia burgdorferi sensu stricto (Bbss), is well documented in the northeastern US, where LB is becoming increasingly prevalent. In coastal North Carolina, I. affinis has been shown to have a higher incidence of Bbss than I. scapularis. My objectives were, to assess changes in prevalence of Bbss in Ixodes spp. along a transect from Virginia to Florida, and to assess the value of dogs and mesomammals as sentinels for spread of Borrelia burgdorferi sensu lato.

Ixodes spp. were collected at sites from 37.4^o N to 30.0^{o …}

Exploitation Of Channel Catfish In Nebraska Flood-Control Reservoirs, Christopher Lee Wiley

School of Natural Resources: Dissertations, Theses, and Student Research

Channel catfish Ictalurus punctatus, is a popular sportfish in North America, and is the third most-sought fish species in Nebraska. Exploitation rates of channel catfish populations have been estimated to be substantial in states neighboring Nebraska. Despite the popularity of channel catfish, little is known about the exploitation of channel catfish populations in Nebraska. The objectives of this study were to estimate the exploitation rates of channel catfish populations, identify the length bias of angling for channel catfish, and identify the self-imposed length limits for channel catfish at flood-control reservoirs of Nebraska. The software package Program Mark was used to …

Climate Change And Plant Demography In The Sagebrush Steppe, Aldo Compagnoni

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.

The Identity Of Rana Margaritifera Laurenti, 1768 (Anura, Bufonidae), Esteban O. Lavilla, Ulisses Caramaschi, José A. Langone, José P. Pombal Jr., Rafael O. De Sá

Biology Faculty Publications

Rana margaritifera was described by Laurenti in 1768 and currently is associated to the genus Rhinella, under the combination Rhinella margaritifera. Currently, the R. margaritifera species group consists of 16 recognized species. Further-more, many additional species have been suggested to exist in this group which highlights the ambiguity surrounding the identity of Rhinella margaritifera and impend further description of the species in this group. After an exhaustive bibliographic review, we concluded that the recent designation of a lectotype for R. margaritifera is invalid according with Art. 73, ICZN, 1999. Herein, we designate and provide the description of a …

A Hands-On Activity To Introduce The Effects Of Transmission By An Invasive Species, Barbara May

Biology Faculty Publications

This activity engages students to better understand the impact of transmission by invasive species. Using dice, poker chips, and paper plates, an entire class mimics the spread of an invasive species within a geographic region. The activity can be modified and conducted at the K-16 levels.

Diet And Prey Availability Of Sturgeons In The Penobscot River, Maine, Matthew Dzaugis

Honors College

Although vital to the protection and conservation of species listed under the U.S. Endangered Species Act, critical habitat of shortnose sturgeon and Atlantic sturgeon in the Penobscot River, Maine have not yet been described. Critical habitat includes food availability as well as the physical characteristics of foraging habitat. To characterize seasonal availability of benthic prey, a ponar grab was used to collect over 125 benthic samples between 21 May and 8 October 2012. Samples were stratified throughout the river and broadly categorized by sediment type. All organisms within samples were identified to the family level. To characterize diet, stomach contents …

The Advertisement Calls And Distribution Of Two Sympatric Species Of Chiasmocleis (Méhely 1904) (Anura, Microhylidae, Gastrophryninae) From The Atlantic Forest, Maruicio C. Forlani, Caio Vinicius De Mira Mendes, Iuri Ribeiro Dias, Danilo Silva Ruas, João Filipe Riva Tonini, Rafael O. De Sá

Biology Faculty Publications

The advertisement calls of Chiasmocleis cordeiroi and C. crucis are described for populations from the municipalities of Igrapiúna and Camacan, respectively, state of Bahia, Brazil. Both calls consist of multipulsed notes produced in series. Differences between the two calls are: dominant frequency, higher in C. cordeiroi (range 4500-4898 Hz; C. crucis range 4069-4435 Hz); note rate, higher in C. cordeiroi (range 6.20--7.46 s/note; C. crucis range 5.17-5.59 s/note); pulse rate, higher in C. cordeiroi (151.82-194.83 s/note; C. crucis range 125.30- 142.12 s/note); and the structure of the modulation patterns of the notes. Moreover, the advertisement calls of C. crucis and …

The Advertisement Call Of The Poorly Known Leptodactylus Tapiti (Anura, Leptodactylidae), Reuber Albuquerque Brandão, Guilherme Fajardo Roldão Álvares, Rafael O. De Sá

Biology Faculty Publications

The genus Leptodactylus consists of approximately 80 species distributed in four nominal groups (Frost 2011). The fuscus group harbors approximately 30 small species with terrestrial nests, deposited in male built burrows on soft soils. Leptodactylus tapiti Sazima & Bokermann 1978 was described from Veadeiros, currently Alto Paraíso municipality, Goiás State, Brazil. The species is restricted to the region of Chapada dos Veadeiros (Frost 2011), where it occurs in areas of water-saturated soils associated with open fields (Sazima & Bokermann 1978). Since its original description, nothing was published about the species, and its advertisement call remains unknown. Herein, we describe its …

Interactions Between Pieris Oleracea And Pieris Rapae (Lepidoptera: Pieridae) Butterflies, And The Biological Control Agents Cotesia Glomerata And Cotesia Rubecula (Hymenoptera: Braconidae)., Megan Herlihy

Megan V Herlihy

Pieris oleracea, formerly Pieris napi, was once a widespread pierid butterfly in New England until the introduction of a biological control agent, Cotesia glomerata. It has been suggested that C. glomerata is responsible for the range reduction of P. oleracea. There are been several introductions of a second more specialized biological control agent, Cotesia rubecula, to the United States since the 1960’s. My first goal was to determine the current distribution and status of P. rapae parasitoids and the effectiveness of C. rubecula as a biological control agent since its release. The findings of a survey I conducted of the …

Habitat Heterogeneity Concentrates Predators In The Seascape: Linking Intermediate-Scale Estuarine Habitat To Striped Bass Distribution, Cristina Kennedy

Masters Theses 1911 - February 2014

Predators are key components of aquatic ecosystems and innovative approaches to understanding their spatial distribution are imperative for research, effective management, and conservation. Discontinuities, created by abrupt changes between two unlike entities, are irregularly-distributed, intermediate-scale features that can have a disproportionate effect on organismal distribution within the seascape. Here I use the discontinuity concept to relate the distribution of a predator, striped bass (Morone saxatilis), to physical features within Plum Island Estuary (PIE), MA. I mapped the distribution of 50 acoustically-tagged striped bass during four monthly surveys at 40 sites to evaluate if heterogeneity in physical features concentrated …

Interactions Between Pieris Oleracea And Pieris Rapae (Lepidoptera: Pieridae) Butterflies, And The Biological Control Agents Cotesia Glomerata And Cotesia Rubecula (Hymenoptera: Braconidae)., Megan V. Herlihy

Masters Theses 1911 - February 2014

Pieris oleracea, formerly Pieries napi, was once a widespread pierid butterfly in New England until the introduction of a biological control agent, Cotesia glomerata. It has been suggested that C. glomerata is responsible for the range reduction of P. oleracea. There are been several introductions of a second more specialized biological control agent, Cotesia rubecula, to the United States since the 1960’s. My first goal was to determine the current distribution and status of P. rapae parasitoids and the effectiveness of C. rubecula as a biological control agent since its release. The findings of a survey …

Pushing Taxonomy To Extiction?, Alessandro Minelli, Annemarie Ohler, Erna Aescht, Aaron Bauer, Lucio Bonato, Roger Bour, Marcelo Rodrigues De Carvalho, Rafael O. De Sá, Et Al.

Biology Faculty Publications

Can we describe all species on Earth before they disappear? We argue that this is possible only by endowing taxonomy with professional manpower and appropriate material resources as required by big science.

Contrary to Costello et al.’s (CMS) (1) statements, taxonomy is not an easy discipline accessible to all through a smartphone. It requires exhaustive training and long familiarity with field, specimens and literature (2).

CMS’s argument is framed in terms of species numbers, but different, non-overlapping species concepts apply to bacteria, brambles and birds (3,4,5): “the species” as common unit of biodiversity does not exist (6).

Even ignoring this …

Reconstruction Of Family-Level Phylogenetic Relationships Within Demospongiae (Porifera) Using Nuclear Encoded Housekeeping Genes, Malcolm Hill, April L. Hill, Et. Al.

Biology Faculty Publications

Background: Demosponges are challenging for phylogenetic systematics because of their plastic and relatively simple morphologies and many deep divergences between major clades. To improve understanding of the phylogenetic relationships within Demospongiae, we sequenced and analyzed seven nuclear housekeeping genes involved in a variety of cellular functions from a diverse group of sponges.

Methodology/Principal Findings: We generated data from each of the four sponge classes (i.e., Calcarea, Demospongiae, Hexactinellida, and Homoscleromorpha), but focused on family-level relationships within demosponges. With data for 21 newly sampled families, our Maximum Likelihood and Bayesian-based approaches recovered previously phylogenetically defined taxa: Keratosa^p, Myxospongiae …

Family Matters: An Analysis Of Genetic Relatedness Of Tetraclita Rubescens (The Pink Volcano Barnacle) Over Several Spatial Scales At Monterey And Bodega Bay, California, Kelly N. Chang

Scripps Senior Theses

Inbreeding involves the mating of closely related individuals at a higher frequency than at random; this can decrease the average fitness of populations and individuals by reducing the presence of heterozygotes and augmenting the expression of deleterious genes. Since marine invertebrates exhibit widespread dispersal, their potential for inbreeding is often disregarded. The adult sessile state of barnacles creates the potential for inbreeding as a result of necessary copulation between neighboring individuals. Depending on the degree of mixing that occurs during dispersal, closely related individuals or siblings may settle in close proximity, generating the possibility of kin aggregation and consequent inbreeding. …

Evaluation Of Antibiotic Resistance Emerging From Use Of Antibiotics In Cafos, J. R. Robbins, D. Hellman, N. Pease, M. Costello

Faculty Scholarship

No abstract provided.

Differential Bait Preference And Rate Of Attraction By Argentine Ants (Linepithema Humile Mayr) At Freshwater And Saltwater Marsh Sites In Southern California, Victor D. Carmona

Victor D. Carmona-Galindo

Ants are a type of foraging insect species which harvests food resources based on availability. When ants locate food resources that are scarce within their habitat, they tend to be more strongly attracted to that food resource. This study used protein, carbohydrate and control based baits to examine if there was a deficiency in resources demonstrated by the ants at two different wetland habitats. We sampled Argentine ants (Linepithema humile Mayr) within the saltwater and freshwater marshes of Ballona Wetlands in Los Angeles, CA. We found significant differences in the rapid deployment of Argentine ants towards protein baits over carbohydrate …