<p>Laser deterrents have been used as a method of deterring birds from problem areas such as fisheries, agricultural fields and airports. This method is considered a nonlethal means of control although lasers are known to cause visual lesions and loss of visual acuity in humans and other animals. Birds have a complex visual system which is necessary for behaviors critical to their survival, such as hunting and foraging, and predator vigilance. The purpose of this study is to determine the safety of laser deterrents for avian eyes using two species of birds: house sparrows (<i>Passer domesticus</i>) and European Starlings (<i>Sturnus vulgaris</i>). We found evidence that laser exposure can cause corneal edema, cataracts, retinal atrophy, displacement of the photoreceptor nuclei, and degeneration of the scleral cartilage. The laser exposure time was an important factor in the likelihood of developing corneal edema and retinal atrophy in starlings. Our findings suggest that lasers may not be completely safe for use as bird deterrents, but further research should be done to find possible solutions to improve laser safety from the avian viewpoint. </p>

This study was conducted to confirm the presence of bovine tuberculosis (BTB) and determine its prevalence, based on skin test reactivity, in cattle reared under extensive farming conditions in the Govuro district, Inhambane province, Mozambique. The study was comprised of a primary screening test using the single intradermal test (SIT) in randomly selected animals from Colonato and Sede dip tanks in Govuro. Positive reactors to the SIT were tested again with bovine and avian tuberculin using the single intradermal comparative test (SICTT) 7 weeks after the SIT. The sample size was calculated using Win Episcope 2.0 based on 95% confidence to detect a 2% expected prevalence using the SIT, with a 1% accepted error and accounting for a total population size of 7208. The calculated sample size was 682 animals. To compensate for the probability of 20% default in reading, the sample size was increased to 853. During the testing process (SIT), it was evident from the first 3 reading days that the apparent prevalence (61, 94%) was higher than expected (2%), hence we decided to stop when the total number of cattle was 530. During the testing process (SIT), it was evident from the first 3 reading days that the apparent prevalence (61.94%) was far higher than expected (2%), hence we decided to stop when the total number of cattle was 530. This was due to the fact that, at such a high prevalence, it would not be necessary to achieve as high a precision as 1% accepted error. A sample size of 530 would be sufficient to achieve a precision of 4% accepted error, which was regarded as more than adequate. The 530 cattle, 3 or more years of age, were selected using systematic random sampling from the two dip tanks (Colonato 371 and Sede 159 animals). All animals were identified by numbers painted, dorsally on the sacral region. Out of 530 tested cattle by SIT, 268 were read, and 166/268 (61.94% with 95% confidence interval [CI]: 55.8 – 67.8%) were found positive, with visible swallow at the injection site. Apparent prevalence (AP) was found to be 61.94% while the true prevalence (TP) was 75.92%. The predictive value of a positive result (PV+) was found to be 87.9%. No significant difference in apparent prevalence between the two areas was detected by Fisher’s exact test (P = 0.11). By SICTT, out of 28 animals positive reactors to SIT, 21 were possible to read, and 13/21 (61.9%; 95% CI: 55.1 – 89.3%) were found positive. A three year old bull, positive reactor to the SIT, was slaughtered, and a detailed post mortem was carried out and organs with visible lesions were collected for further laboratory testing (histopathology, culture and isolation of M. Bovis and PCR). Later on, 30 more positive reactors to the SIT test were slaughtered: 25/30 (83.3%) showed visible lesions compatible with BTB, and total condemnation of carcass was made in 3/25 (12%) due to generalized lesions. The high prevalence rate of skin test positive animals as well as gross lesions and histopathology were confirmed to be BTB by the isolation and identification of M. Bovis by culture and PCR. Our results suggest that bovine tuberculosis is highly prevalent in Govuro district and may thus represent a potential health problem of zoonotic tuberculosis in humans. Our results suggest that BTB has reached the plateau phase of endemicity in cattle in Govuro district. In this context, the positive predictive value of the SIT is very high and thus the use of the SICTT as a confirmatory test has a limited value and should not be advocated. Our results further indicate that no other prevalence study of BTB should be conducted in the next few years in Govuro district, unless comprehensive control measures are implemented. The focus of further studies should be on the isolation and the molecular characterization of M. Bovis from cattle and humans in order to assess transmission routes and the role played by BTB in human TB cases in Govuro district. Copyright / Dissertation (MSc (Veterinary Tropical Diseases))--University of Pretoria, 2009. / Veterinary Tropical Diseases / unrestricted

This thesis investigates how the Bear River marsh’s protection became a national interest and a cause for conservation in the Progressive Era. The thesis documents how the marsh declined because of irrigation development culminating with an outbreak of avian botulism in 1910, and traces the long process to protect the marshland. The research focused on examining local water development patterns of the nineteenth and early twentieth centuries, ornithological research in the 1910s, and the national sportsmen’s conservation movement of the 1920s. Upon examination of these events, it becomes clear that a coalition of ornithologists, sportsmen, and policy makers worked together to institute change that affected the marsh. Through showing how groups came together in the past to work for conservation, this research highlights the important role that a coalition of groups can have in reshaping how a landscape is viewed and managed.

I assessed avian communities of Gam bel oak (Quercus gambelii) woodland and surrounding habitats at Camp W. G. Williams State Military Reservation , Utah, during summer of 1993-1998. I used point counts and incidental observations to compile an avian checklist. I observed 100 species, accounting for one third of all birds known from Utah. Overlap in species composition among habitats was considerable, yet each habitat supported a distinct complement of common species. I compared bird species composition, abundance, richness, and diversity before and after fire in burned and unburned Gam bel oak woodland using point counts. I also investigated how similarity of the Gam bel oak avian community to surrounding communities changed after fire. Post-fire changes in individual species abundances reflected a shift from a woodland to a grassland/shrubland community. However, this shift occurred through elimination rather than addition of species, i.e., the post-fire Gambel oak avifauna was a subset of the pre- fire avifauna. Species richness and diversity on burned plots decreased significantly after fi re; unburned plots experienced significant increases in richness and diversity. I also used point counts to evaluate recovery of the Gam bel oak avian community by comparing species composition, abundance, richness, and diversity in different-age burned and unburned Gambel oak woodland. Total abundance, richness, diversity, and similarity to the unburned community increased with post-fire age. I observed significant differences in the abundance of 10 species. Fire did not result in sequential invasion and replacement of bird species assemblages; rather, species found in burned plots were a subset of the avifauna in unburned plots. Return of individual species was related to recovery of preferred nesting and foraging substrates. Over 25% of species found in unburned plots were still absent 11 years post-fire. I conclude that fire had pronounced effects on avian community composition and structure in this habitat. The contention that almost all bird species associated with Gambel oak woodlands are tolerant to fire is not substantiated by the results of this study. Due to the lack of spatial replication in this study, a comparison of avian response to fire in several sites across Gambel oak range would be desirable.

We investigated the effects of different fire restoration treatments on five shrubsteppe bird species in the Great Basin of central Utah. Sagebrush communities and the associated avifauna are under particular threat due to changing fire regimes. Although fires are locally destructive, it is hypothesized that they improve habitat by increasing landscape-level heterogeneity. As long as fire follows a historic fire regime, the plant and animal communities can usually recover. However, fires can and often do burn outside of the normal regime. The Milford Flat Fire, which occurred in west-central Utah, was the largest wildfire recorded in the Great Basin. Considered catastrophic, concern existed that natural recovery of sagebrush and its avifauna would be unlikely. To prevent this, vegetation reseeding treatments were applied immediately post-fire. These treatments included two seed mix types, with or without a shrub component, and three mechanical applications, drill seeding, aerial seeding followed by chaining, and aerial seeding only. We surveyed the avian community in the different treatment types and in untreated areas within the fire using line transect distance sampling methods. Using a space for time substitution, we sampled nearby unburned areas as reference to represent pre-fire conditions. We hypothesized that the treatment areas would be more similar to the reference than the untreated areas, and that the treatments would all have similar effects. We found some effect on the presence and extirpation of the birds at the guild and overall bird level. We found no significant effect from the treatments on the five study species at the species level, and no effects on bird densities. The effects of the restoration treatments were overshadowed by the effect of the fire on changing the habitat, namely, the density of sagebrush. We saw a pattern of birds responding to the removal or survival of sagebrush and the treatments were insufficient in affecting a short term response.

A study was conducted in Rich County, Utah to determine the extent of avian tuberculosis in livestock, poultry and wild birds. Sensitivity was elicited in cattle, swine and chickens by tuberculin testing. The Mycobacterium avium organism was obtained from tissues and specimens of cattle, swine, goats, chickens, magpies and sparrows. Methods of eradication of avian tuberculosis and the relationship of avian tuberculosis to mammalian tuberculosis are discussed.

Purpose and scope Each year thousands of western waterfowl succumb to disease, predators, mechanical injury and other decimating factors . Based on a review of records it is conservatively estimated that an average of 25,000 ducks have succumbed to botulism on western marsh areas annually. In a recent study, the United States Fish and Wildlife Service valued each duck and goose at $8.00 (McLeod, 1950). Applying this value to the estimated annual numerical loss, a total of $200,000 has been lost each season in mortality of western waterfowl from botulism. Control of this malady would reduce annual waterfowl and monetary losses. Prevention and cure are the only means of controlling botulism in wild ducks. At present, no economical preventative measure exists and control is based on curing stricken birds. The purpose of this study was to evaluate the cost of treatment and rate of recovery of birds stricken with botulism when treated by selected methods . The 4 treatments selected for evaluation were: (1) hospital inoculation, (2) fresh water, (3) field inoculation, and (4) no treatment or control . Research included a comprehensive evaluation of factors such as age, sex, species, body condition, degree of affliction, reaction to various amounts of antitoxin, and reaction t o selected treatment methods, thought to be pertinent in botulism control. This study was conducted during botulism outbreaks of 1953 and 1954, and was confined to state-owned marshlands of Utah. Study areas Three major areas provided sick birds used in this research: (1) Ogden Bay Refuge, (2) Farmington Bay Refuge, and (3) the Public Shooting Grounds . These man-made marsh areas are located on the saline flat lands adjacent to Great Salt Lake. The majority, 1,979 or 89.3 percent, of sick birds were taken from Ogden Bay Refuge on the Weber River Delta. This state-owned waterfowl refuge contains approximately 13,700 acres of diversified habitat . Excellent conditions for the production and existence of Clostridium botulinum, type c, the causative agent of botulism, were apparently present throughout the area. Farmington Bay Refuge, approximately 20 miles south of Ogden Bay Refuge in Davis County, Utah, was dried for improvements in 1953, but was traversed regularly during the 1954 season. In preparation for the hunting season, water was diverted into the north lake of Farmington Bay on October 1, 1953. A two-man crew picked up and disposed of approximately 2,000 dead ducks from approximately 20 acres of the reflooded marsh on October 6, 1953. This was the most serious outbreak of the study and indicated the rapidity with which sickness advanced. Few sick birds were noted, which indicated that the crisis had passed. Farmington Bay Refuge provided 121 of the 2,214 ducks treated during 1953 and 1954. Not more than 12 sick or dead birds were seen on the Public Shooting Grounds, 8 miles west of Corinne, Utah, in 1953. During the 1953 season, 3 sick birds were transported from the area to Ogden Bay Refuge for treatment. In 1954 this state-owned shooting area supplied lll sick birds for treatment. Other areas were observed during the study but did not provide sick birds for treatment. These areas consisted of : (1) State -owned lands beyond Bear River Migratory Bird Refuge, and (2) Smith and Utah Lakes west of Provo, Utah.

The goal of this investigation was to determine the potential of birds as vectors for the movement of dwarf mistletoe seeds and the means by which such movement could occur. Birds would greatly speed the rate at which these parasites move horizontally or vertically through the forest. Five areas in Oregon, heavily infected by six species of Arceuthobium were studied. Observations of avian behavior point to 13 species whose general behavior make them potential vectors in the distribution of these parasites. More specifically, the roosting and subsequent bathing behavior of most forest birds proves a very important means of potential seed transport. Additionally, an examination of nesting materials revealed that birds bring viable dwarf mistletoe seeds to infectible portions of host trees during the construction of their nests. Nesting, however, seems the least important of the vector mechanisms discussed. I observed no evidence of birds feeding on the seeds of dwarf mistletoe or of seeds being present in their droppings. The more probably means of seed transport is one of epizoochory.

No description available.

Past grassland restoration efforts in the Prairie Pothole Region (PPR) of North America often aimed to restore nesting habitat for waterfowl species. A low-diversity non-native grass and forb seeding mix, known as Dense Nesting Cover (DNC), was frequently used in restoration, and was believed to benefit the broad diversity of wildlife dependent upon restored grasslands. However, grasslands restored with DNC often experience high rates of invasion by non-native vegetation species, and maintenance of these restorations is expensive and requires intensive management. More recently, high-diversity native seeding has been explored as a restoration strategy to decrease the cost of DNC maintenance and provide resources for a greater number of grassland dependent fauna. However, there are gaps in the information concerning how grassland-dependent fauna respond to these restorations, and as such, there is hesitation among land managers to invest in the initial higher cost of high-diversity native seeding mixes until faunal responses are known. The goals of this research were to (1) understand how vegetation diversity, richness, and cover type, variables directly influenced in reseeding restoration, impact grassland-dependent faunal communities; (2) understand how vegetation structure influences the grassland dependent faunal communities to inform post-restoration management activities; and (3) understand how waterfowl and grassland passerines respond to grassland vegetation, structure and landscape variables, in efforts to understand which restoration strategies may be most beneficial to the broader grassland bird community. To perform this study, I selected 26 study sites representing a gradient of vegetation species richness and three cover types; unseeded native grassland (Native), low-diversity and non-native Dense Nesting Cover (DNC), and high-diversity native seed mix (HDM). At each study site, I documented the responses of grassland arthropods, small mammals, grassland birds to vegetation cover type, richness, diversity and structure. I also assessed how vegetation cover type influenced differences in community structure of each of the taxonomic groups. Additionally, because I suspected that bird species are also likely to respond to landscape-level and nest-site level habitat characteristics, I accounted for these variables in our bird models. In Chapter One of this dissertation, I studied the effects of vegetation species richness, diversity and structure on grassland arthropod communities at 23 of our study sites. Arthropod sampling was conducted during July of 2016 using pan traps and sweep net surveys. The goal of using two methods of evaluation was to account for a greater proportion of species in the arthropod community and target taxa that inhabit different parts of the vegetation (i.e., pan traps are better for surveying pollinators and ground dwelling arthropods, whereas sweep net surveys better target arthropods that live higher in the vegetation such as leafhoppers). A total of 25,521 arthropods representing 107 taxonomic families were collected. Vegetation richness and diversity, cover type, percent live vegetation and native cover, and litter depth were important predictors of arthropod community measures, and multivariate analysis of the arthropod community indicated significant differences between Native and DNC sites, which was explained by differences in vegetation richness, percent forb cover, and litter depth. Results suggest that species richness of grassland restoration seeding mixes likely impacts arthropod richness and diversity, and DNC does not produce arthropod communities similar to native grassland. Additionally, because vegetation structural variables were important determinants of arthropod community measures, grassland management practices will influence the resulting arthropod community and influence the success of grassland restoration seed mixes. Results demonstrate the potential for successful restoration outcomes using high-diversity seed mixes, and indicate that low-diversity, non-native seed mixes, such as DNC, do not restore native grassland arthropod communities. In Chapter Two, I assessed the responses of the grassland small mammal community to vegetation cover type, as well as richness, diversity and structure of the vegetation community. During July 2014 to 2016, I used Sherman live traps to survey grassland small mammal communities on 24 study of my study sites. Small mammal abundance was highest at low-diversity DNC sites, and lowest in native grassland. Small mammal diversity was highest at HDM sites and lowest at DNC restoration sites. I selected three focal species to investigate small mammal responses to grassland vegetation including Peromyscus spp., Microtus spp., and Ictidomys tridecemlineatus. Abundances of the different focal taxa were influenced by different vegetation structural variables. Peromyscus spp. abundance was negatively influenced by percent native vegetation cover, Microtus spp. abundance showed yearly variation and was impacted positively by litter depth and negatively by vegetation richness, and Ictidomys tridecemlineatus abundance was influenced by cover type. Small mammal communities of DNC sites differed from Native sites, but HDM was not different from Native or DNC. Ictidomys tridecemlineatus abundance was higher at Native and HDM sites, while DNC sites had higher Peromyscus spp. abundance. Results indicate species-specific management is required to meet small mammal management goals, and diversity of the restoration seed mix is likely to influence grassland small mammal communities. Additionally, DNC is not supporting small mammal communities similar to what is observed at Native grassland sites. In Chapter Three of this dissertation, I investigated the responses of grassland bird communities to vegetation richness, diversity, structure on all study 26 sites. I conducted nest searches for waterfowl during May to July of 2014 to 2016, and searched for grassland passerines and other non-waterfowl bird species during May to July of 2015 and 2016. In 2016, I conducted additional point count surveys to detect bird species that may have been unaccounted for in nest searches. A total of 998 waterfowl nests of nine species, 282 passerine nests of nine species, and 32 nests of 10 other bird species were located. Five hundred and nineteen birds of 20 species were encountered in point count surveys. Richness and diversity of bird nesting and point count communities differed among cover types, and sites restored with HDM seeding had lower bird richness and diversity. Richness and diversity of the vegetation positively influenced the richness and diversity of both the bird nesting and point count communities. Multivariate analysis of the nesting communities indicated significant difference among HDM, Native, and DNC sites, and this was best explained by percent native vegetation cover, vegetation species richness, and vegetation density. Multivariate analysis of the point count communities did not reveal significant difference among cover types, but the structural variables vegetation density and litter depth were important explanatory variables for the ordination. Results study indicate that manipulation of vegetation species richness and diversity that occurs in high-diversity restoration has the potential to influence the grassland bird community, whereas greater vegetation richness and diversity are likely to support more diverse bird communities, but management of vegetation density will be an important management consideration. In Chapter Four, I investigated species-specific responses to vegetation diversity, richness, structure, and landscape variables in order to determine whether management efforts anticipated to benefit a particular taxonomic group of grassland bird species (i.e., waterfowl) are likely to meet the needs of other grassland-dependent birds (i.e., passerines) and to inform management efforts aimed at conserving and creating nesting habitat for grassland waterfowl and passerines. I used generalized linear mixed-models (GLMM) to determine which variables at the landscape, patch, and nest-site level were most influential to the nesting density and daily survival rates (DSR) of our primary focal species. Focal species included five waterfowl species: Blue-winged Teal (Spatula discors; N=365), Gadwall (Mareca strepera; N=173), Mallard (Anas platyrhynchos; N=302), Northern Pintail (Anas acuta; N=64), and Northern Shoveler (Spatula clypeata, N=61), and three species of grassland passerines: Bobolink (Dolichonyx oryzivorus; N=31), Clay-colored Sparrow (Spizella pallida; N=190), and Savannah Sparrow (Passerculus sandwichensis; N=20). Cover type only impacted two of our focal species, Blue-winged Teal and Clay-colored Sparrow, and density of both species was highest at HDM sites and lowest at DNC sites. Vegetation diversity and richness did not impact the nesting density of the majority of our focal species, but Northern Shoveler nesting density was negatively associated with vegetation species richness. DSRs of Northern Pintail and Gadwall were positively associated with vegetation species richness, and Bobolink DSR was negatively influenced by vegetation diversity. Responses to the other landscape-level and vegetation covariates of interest were mixed among species, and little consistency was observed across waterfowl or passerine species. However, at the landscape-level, several waterfowl and passerine species had lower DSRs associated with landscape-level components that contribute to the fragmentation of grasslands including wooded edges, crop fields, and developed areas (i.e., roads and buildings). Results indicated that waterfowl and passerine species respond to different parts of grassland vegetation, and successful management and restoration for nesting grassland birds will require the development of heterogenous habitat that provides resources for the diversity of grassland birds nesting at restored sites. Findings suggest that restoration that involves manipulating diversity, richness, or origin of the vegetation in grasslands through reseeding should be expected to directly influence grassland faunal communities. Because the taxa investigated in this study are responding to different aspects of the vegetation structure, management efforts should be multifaceted, and account for the differing needs of the diversity of grassland fauna dependent upon restored sites. Results also indicated that greater vegetation species richness and diversity results in a more rich and diverse wildlife community, and high-diversity native reseeding should be expected to promote more rich and diverse faunal communities, but successful implementation of high-diversity native reseedings will necessitate proper management of vegetation structure. Finally, all taxonomic groups studied demonstrated positive responses to native grassland habitat, regardless of vegetation richness and diversity. Therefore, preservation of native grassland and promotion of habitat heterogeneity should be prioritized in grassland conservation and restoration efforts.