Geology topics

Charlotte Quist

Publications and source records attributed to Charlotte Quist.

3 recordsLinked to original sources

USGS2010

Granular cell tumor in an endangered Puerto Rican Amazon parrot (Amazon vittata)

A 3 cm diameter mass from the metacarpus of a Puerto Rican Amazon parrot was diagnosed as a granular cell tumour based on light microscopy. The cytoplasmic granules were periodic-acid Schiff positive and diastase resistant. Ultrastructural characteristics of the cells included convoluted nuclei and the presence of numerous cytoplasmic tertiary lysosomes. This is only the second granular cell tumour reported in a bird. We speculate that most granular cell tumours are derived from cells that are engaged in some type of cellular degradative process, creating a similar morphologic appearance, but lacking a uniform histogenesis.

Avian Pathology↗

USGS2005

Attempts to identify the source of avian vacuolar myelinopathy for waterbirds

Attempts were made to reproduce avian vacuolar myelinopathy (AVM) in a number of test animals in order to determine the source of the causative agent for birds and to find a suitable animal model for future studies. Submerged vegetation, plankton, invertebrates, forage fish, and sediments were collected from three lakes with ongoing outbreaks of AVM and fed to American coots ( Fulica americana ), mallard ducks and ducklings ( Anas platyrhynchos ), quail ( Coturnix japonica ), and laboratory mice either via gavage or ad libitum. Tissues from AVM-affected coots with brain lesions were fed to ducklings, kestrels ( Falco sparverius ), and American crows ( Corvus brachyrhynchos ). Two mallards that ingested one sample of Hydrilla verticillata along with any biotic or abiotic material associated with its external surface developed brain lesions consistent with AVM, although neither of the ducks had clinical signs of disease. Ingestion of numerous other samples of Hydrilla from the AVM affected lakes and a lake with no prior history of AVM, other materials (sediments, algae, fish, invertebrates, and water from affected lakes), or tissues from AVM-affected birds did not produce either clinical signs or brain lesions in any of the other test animals in our studies. These results suggest that waterbirds are most likely exposed to the causative agent of AVM while feeding on aquatic vegetation, but we do not believe the vegetation itself is the agent. We hypothesize that the causative agent of AVM might either be accumulated by aquatic vegetation, such as Hydrilla , or associated with biotic or abiotic material on its external surfaces. In support of that hypothesis, two coots that ingested Hydrilla sampled from a lake with an ongoing AVM outbreak in wild birds developed neurologic signs within 9 days (ataxia, limb weakness, and incoordination), and one of two coots that ingested Hydrilla collected from the same site 13 days later became sick and died within 38 days. None of these three sick coots had definitive brain lesions consistent with AVM by light microscopy, but they had no gross or histologic lesions in other tissues. It is unclear if these birds died of AVM. Perhaps they did not ingest a dose sufficient to produce brain lesions or the lesions were ultrastructural. Alternatively, it is possible that a separate neurotoxic agent is responsible for the morbidity and mortality observed in these coots.

Journal of Wildlife Diseases↗

USGS2003

Human-induced contaminant impacts on migratory birds: Lessons from the North American eared grebe ( Podiceps nigricollis )

The effects of aquatic contaminants generated by soda ash mining processes on the North American eared grebe ( Podiceps nigricollis ) population illustrates important issues associated with human-induced habitat degradation on the health of migratory species. Eared grebes have been extensively studied in their staging and breeding habitats, but little is known about their 2- to 3-day migratory periods. During migration, few bodies of water are available to the birds for refuge between freshwater breeding areas in Canada and hypersaline lakes (e.g., Great Salt Lake in Utah or Mono Lake in California) to which they migrate. One geographic refuge area includes a series of "tailings" ponds associated with soda ash mining operations in southwestern Wyoming. The ponds range from 100-1200 acres, with water containing high concentrations of sodium decahydrate (Na 2 CO 3 •10H 2 O). At cool temperatures (generally < 40°F) sodium decahydrate precipitates out of the water and crystallizes on solid objects in the ponds or on the water surface. Bird mortality on these ponds has been recognized since the early 1970's, and the mining companies have developed hazing strategies and rehabilitation programs in order to minimize mortality. In order to determine causes of grebe mortality and devise strategies to reduce mortality, a field epidemiologic investigation was developed with the following objectives: 1) to determine whether eared grebes have quantifiable physiologic abnormalities associated with exposure to soda ash mine pond water; 2) to evaluate physical effects of sodium decahydrate crystallization on grebe survival; 3) to establish cause of death based on necropsy of deceased grebes; 4) to determine long-term survivability of eared grebes after exposure to the pond water; and 5) to evaluate water quality and determine whether aquatic invertebrates are present in the ponds as a possible food source.

California, Utah↗