Digital Commons Network^™

Efficacy Of Gonacon Fertility Control Against Prairie Dogs And Potential For Uses On Other Rodent Species, Aaron B. Shiels, Emily W. Ruell, Jason E. Bruemmer

United States Department of Agriculture Wildlife Services: Staff Publications

Use of a contraceptive (i.e., fertility control) is attractive for rodent management where lethal control is unwanted. Although population reduction is generally unachievable with small-scale, short-term contraceptive use, reduced juvenile recruitment is achievable. The injectable immunocontraceptive vaccine GonaCon (active ingredient: gonadotropin releasing hormone [GnRH]) was registered in 2022 by the United States Environmental Protection Agency (EPA) for controlling fertility of female prairie dogs (Cynomys, a type of ground squirrel) in urban/suburban settings. Here we: 1) describe past research, including a replicated field study in Colorado (GonaCon treatment vs. control sites) testing efficacy of GonaCon in prairie dogs, which …

Development Of A Novel Vertebrate Pesticide For The Invasive Small Indian Mongoose, Carmen Antaky, Steven C. Hess, Israel Leinbach, Robert T. T. Sugihara, Emily W. Ruell, Shane Siers

United States Department of Agriculture Wildlife Services: Staff Publications

Small Indian mongooses are detrimental introduced predators in the United States, where they depredate native species, serve as vector of disease, and threaten public safety. Due to the risk of accidental introduction to mongoose-free islands, high cost and limitations to trapping, and no national (Section 3) Environmental Protection Agency (EPA)-registered toxicants for mongoose control, there is a need for an efficacious toxic bait for mongooses for use in conservation areas and at points of entry in the United States. Over the last five years, the National Wildlife Research Center (NWRC) worked to develop a toxic bait for mongooses for registration …

Matching Watershed And Otolith Chemistry To Establish Natal Origin Of An Endangered Desert Lake Sucker, Deanna Strohm

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Like many native endemic desert freshwater fish species, the June Sucker (Chasmistes liorus) is currently listed as endangered. Managers have increasingly turned to habitat restoration as a key component to recovery plans. For endangered species, one of the primary outcomes of habitat restoration is that it should result in successful reproduction and recruitment of individuals into the adult population. Confirmation of natural recruitment as a function of habitat restoration can only be achieved by establishing natal origins.

Recent research has proven the validity of otolith microchemistry, a technique that analyzes small quantities of elements, to trace potamodromous fish …

Using Otolith Microchemistry To Classify Yellow Perch As Stocked Or Naturally Produced, Andrew K. Carlson, Matthew J. Ward, Brian D.S Graeb

The Prairie Naturalist

Fisheries managers routinely use stocking to supplement fish populations (Schramm and Piper 1995, Fisher 1996). Stocking eyed-eggs offers substantial cost savings compared to stocking fry and fingerlings (PFBC 2011); however, traditional stocking evaluation using oxytetracycline (OTC) marking of otoliths is ineffective for eyed-eggs of some species (e.g., yellow perch, [Perca fla- vescens]). Thus, there is a need for additional approaches to be able to classify fish as stocked or naturally produced. Fish otoliths are paired calcified structures in the inner ear that permanently deposit trace elements in proportion to water column concentrations (Campana 1999, Campana et al. 2000). Coupled with …

The Impact Of Multiple Nursery Areas On The Population Structure Of Atlantic Menhaden, Brevooria Tyrannus, Kristen A. Anstead

OES Theses and Dissertations

Understanding the population structure and patterns of connectivity in marine fishes is essential when making predictions about a species' resiliency and persistence in an increasingly changing environment. The Atlantic Menhaden Brevoortia tyrannus is a clupeid that plays a critical role in the marine food web and supports one of the largest fisheries on the US East Coast. In addition to a decrease in overall numbers and spawning stock biomass, recruitment levels have remained low since the 1990s. Menhaden use numerous estuaries along the Atlantic coast for juvenile development before recruiting to the adult population and the contribution of each of …

Effect Of Laser Ablation Depth In Otolith Life History Scans, Renée R. Hoover, Cynthia M. Jones

OES Faculty Publications

Life history scans of fish otoliths are bringing new insight into the structure, connectivity, and movement of fish populations. Data obtained from such scans, however, possess in-herent limitations that have not yet been fully addressed or understood. For example, several investigators have noted delays in otolith elemental uptake that do not appear to reflect habitat exposure. We hypothesized that the 3-dimensional structure of otoliths may produce sampling artifacts in the results obtained from laser ablation scans. To test this hypothesis, we sampled sagittal otoliths from juvenile Atlantic croaker Micropogonias undulatus with laser ablation inductively coupled plasma mass spectrometry to obtain …

Homoploid Hybrid Speciation In A Rare Endemic Castilleja From Idaho (Castilleja Christii, Orobanchaceae), Danielle Leigh Clay

Boise State University Theses and Dissertations

Evidence to support the origins of a putative hybrid species with certainty must be determined using several lines of evidence: the presence of genetic additivity of parental marker alleles in a putative hybrid species, along with ecological or niche separation. Novel or transgressive morphological traits obtained through chromosomal rearrangements during hybridization may facilitate niche separation of the hybrid species from progenitor habitats. These evolutionary processes together enforce reproductive isolation and promote an independent evolutionary trajectory in hybrid species. By studying these evolutionary processes in putative hybrid species, researchers may identify hybrid species with confidence.

We employed multiple lines of evidence …

What Are The Causes, Consequences And Correctives Of Fish Contamination In The Detroit River Aoc That Cause Health Consumption Advisories? (Final Report, Michigan Sea Grant Michu-T-10-001), Donna R. Kashian, Ken G. Drouillard, D. Haffner, Ann E. Krause, Z Liu, Larissa Sano

Environmental Science and Geology Faculty Research Publications

Using an Integrated Assessment (IA) framework, we consolidated and utilized existing data from the Detroit River to develop models that both identify possible drivers of elevated fish contaminant body burdens, and to facilitate a more risk-based approach of tissue trigger-levels for consumption advisories. This integrated assessment approach was particularly useful for consumption advisories as it provided the ability to integrate and organize complex data in a manner that can help inform management decisions. In addition, the IA framework explicitly fosters collaboration and participation of multiple interested groups. We have capitalized on this component of IAs, by seeking the active participation …

A Reconnaissance Of The Intersex Condition In Micropterus Dolomieu Of The Upper Ohio River Basin As An Indicator Of Anthropogenic Endocrine Disruptors, Christopher Barry

Theses, Dissertations and Capstones

The intersex condition has been used as a marker of endocrine disruption in West Virginia. Fifty-two male smallmouth bass from 6 basins on the upper Ohio River were examined for the presence and severity of intersex. Vitellogenin (VTG) RNA levels were quantified as marker of estrogenic contaminants. A significant increase in intersex (p=0.02), ranging from 83.3% to 100%, corresponds with higher population densities and agricultural land (p=0.003). At reference sites, smallmouth bass had intersex frequencies of 16.7% to 33.3%. Vitellogenin results were significantly lower (p< 0.001) at impacted sites, consistent with previously reported results in female fish. VTG levels in males were not significantly different. Increased intersex occurrence in males and lowered VTG expression in females have shown that agricultural chemicals and common residential wastewater constituents are likely targets for exploring the relationship between individual EDCs and intersex. There may be a natural background level of the intersex condition.

Experimental Investigation Of Elemental Incorporation In The Otoliths Of Larval And Juvenile Fish: Implications For Use As Environmental Recorders, Gretchen Bath Martin

Biological Sciences Theses & Dissertations

Innovative techniques for discerning fish stocks, identifying nursery habitats, locating spawning sites, tracing larval transport pathways, and quantifying the degree of population connectivity are required to meet the goals of sustainable management of marine capture fisheries. One of the most promising techniques is the use of elemental signatures in fish otoliths (ear stones), which record valuable life history data and serve as the link between fish and their environment. To validate the assumption that otolith elemental composition is a function of water elemental concentrations, and to address the possible effects of external variables such as temperature and salinity, the composition …

Development Of Diagnostic Approaches To Determine Sources Of Anthropogenic Stress Affecting Benthic Community Conditions In The Chesapeake Bay, Daniel M. Dauer, Michael F. Lane, Roberto J. Llansó

Benthic Applications

Benthic macrofauna are an important component of estuarine ecosystems. These organisms are a food source for higher trophic levels including fishes and crabs (Virnstein 1977, 1979; Holland et al. 1980; Dauer et al. 1982) and birds (Botton 1984; Quammen 1984). Benthic macrofauna affect both the physical and chemical properties of the sediment and the overlying water column (e.g., Rhoads and Young 1970; Rhoads 1973; Aller 1978, 1980), influence nutrient cycling (Rowe et al 1975; Zeiteschel 1980; Flint and Kamykowski 1984), and are capable of directly controlling phytoplankton biomass in the water column (Cleorn 1982; Officer et al 1982; Cohen et …

Effects Of Developmental Activities On Streamside Salamander Communities In Boone County, West Virginia, Mindy S. Hamilton

Theses, Dissertations and Capstones

A study was conducted from May 1998 through June 1999 in three streams associated with mountaintop mining and valley fills in Boone County, West Virginia. Streamside salamander communities were monitored in these streams, as well as in two relatively undisturbed reference streams in the region, using refugia bags, rock-on-rock methodology, and day surveys. The relative abundance of salamanders was compared between the streams in order to detect effects of the associated valley fills to downstream biota. Relative abundance was lower in two of three streams associated with valley fills as compared to the reference streams. However, there was no significant …

Accurate Classification Of Juvenile Weakfish Cynoscion Regalis To Estuarine Nursery Areas Based On Chemical Signatures In Otoliths, Simon R. Thorrold, Cynthia M. Jones, Peter K. Swart, Timothy E. Targett

OES Faculty Publications

We investigated the ability of trace element and isotopic signatures in otoliths to record the nursery areas of juvenile (young-of-the-year) weakfish Cynoscion regalis from the east coast of the USA. Juvenile C. regalis were captured with otter trawls at multiple sites in Doboy Sound (Georgia), Pamlico Sound (North Carolina), Chesapeake Bay (Virginia), Delaware Bay (Delaware) and Peconic Bay (New York), from July to September 1996. One sagittal otolith from each specimen was assayed for Mg/Ca, Mn/Ca, Sr/Ca and Ba/Ca ratios using inductively coupled plasma mass spectrometry (ICP-MS), while delta 13 C and delta 18 O values from the other sagittal …

Micronutrients And Biological Patterns In Lake Mead, Hasan K. Qashu, Lorne G. Everett, J. S. Carlson, Bureau Of Reclamation

Publications (WR)

Progressive increases in concentration of dissolved solids in the Colorado River water from Lake Powell to Imperial Dam seem to alter plankton dynamics and biological productivity of the river. Also, changes in biological productivity and micronutrients concentrations occur within the same reservoir. Development of a digital simulation model to predict micronutrients concentrations and biological productivity is necessary for diagnosing changes in plankton population and effluent-carrying capacity of the system. The objectives of the study are: (1) to determine trace metal balance at different locations in Lake Mead, (2) to measure biological productivity and conduct plankton population counts at each sampling …

Water Chemistry Survey Of Boulder Basin, Lake Mead, P. R. Tramutt, Bureau Of Reclamation

Publications (WR)

The survey results indicate that the impoundment of water behind Hoover Dam has not adversely affected the dissolved oxygen (DO) content and that water quality and DO content were uniform regardless of depth. The study made in April-May 1964 will provide water quality data of Lake Mead prior to releases from Lake Powell as a basis for evaluating Lake Powell's effect on water quality and limnology of Lake Mead. The performance of a DO analyzer was tested and found unsatisfactory at depths below 150 ft. Parameters tested by standard chemical analyses of water samples in the Denver Laboratory and by …