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Full-Text Articles in Life Sciences

Botswana’S Elephant-Back Safari Industry – Stress-Response In Working African Elephants And Analysis Of Their Post-Release Movements, Tanya Lama Jan 2017

Botswana’S Elephant-Back Safari Industry – Stress-Response In Working African Elephants And Analysis Of Their Post-Release Movements, Tanya Lama

Masters Theses

Understanding how African elephants (Loxodonta africana) respond to human interactions in ecotourism operations is critical to safeguarding animal and human welfare and sustaining wildlife ecotourism activities. We investigated the stress response of elephants to a variety of tourist activities over a 15-month period at Abu Camp in northern Botswana. We compared fecal glucocorticoid metabolite (FGM) concentrations across three elephant groups, including: eight elephants in an elephant-tourism operation (Abu herd), three elephants previously reintroduced back into the wild from the Abu herd, and wild elephants. There were no differences in FGM concentrations between the three groups of elephants. The highest observed ...


The North American River Otter (Lontra Canadensis) On The Department Of Energy's Savannah River Site, Emily B. Mccallen Jan 2017

The North American River Otter (Lontra Canadensis) On The Department Of Energy's Savannah River Site, Emily B. Mccallen

Masters Theses

The Department of Energy's (DOE) Savannah River Site (SRS) faces a legacy of radionuclide and metal contamination from industrial processes that occurred within the site. The risks posed to ecosystems on the site from contaminants are quantified using the ecological risk assessment process, which often uses the health of a particular species as an ecological endpoint. Northern river otters (Lontra canadensis) are appropriate receptors for studying the effects of long-term, low-level contamination because they are long-lived, higher trophic level organisms likely to accumulate high levels of pollutants. However, little information about river otters on the SRS is known; in ...


Quantifying Bat Detection Survey Methods And Activity Patterns, Tara C. Hohoff Jan 2016

Quantifying Bat Detection Survey Methods And Activity Patterns, Tara C. Hohoff

Masters Theses

Bats have an astonishing diversity and provide vital ecosystem services in an array of different niches. In North America, most species of bats are insectivores and tend to be frequently overlooked for their important ecosystem role providing insect control. As bat populations have declined in recent years, farmers, land managers, conservationists, and bat enthusiasts have wondered what we can do to protect our local bat populations. As a first step, we need to develop methods that more effectively survey for rare species of bats. By performing inefficient surveys, we are doing a disservice to our funding agencies providing misinformation that ...


Assessment Of The Efficacy Of The Hose-Bridge As A Road-Crossing Structure For Dekay's Brownsnake (Storeria Dekayi), Sarah Elizabeth Manka Jan 2016

Assessment Of The Efficacy Of The Hose-Bridge As A Road-Crossing Structure For Dekay's Brownsnake (Storeria Dekayi), Sarah Elizabeth Manka

Masters Theses

Various structures have been integrated into roadways to ensure the road does not impede wildlife movements between adjacent habitats. Where traffic volume is low, the costs of installing and maintaining such structures is typically prohibitive. I tested the efficacy of a hose-bridge deployed temporarily on a State Park road in Illinois that allowed the passage of cars over it and small wildlife species to cross through it. I predicted that, during the 4.5 -week period of peak migratory movement, road-based mortality of Dekay's Brownsnakes (Storeria dekayi) would be less at the site having the hose-bridge, when compared to ...


Rare Occurrences Of Free-Living Bacteria Belonging To Sedimenticola From Subtidal Seagrass Beds Associated With The Lucinid Clam, Stewartia Floridana, Aaron M. Goemann Dec 2015

Rare Occurrences Of Free-Living Bacteria Belonging To Sedimenticola From Subtidal Seagrass Beds Associated With The Lucinid Clam, Stewartia Floridana, Aaron M. Goemann

Masters Theses

Lucinid clams and their sulfur-oxidizing endosymbionts comprise two compartments of a three-stage, biogeochemical relationship among the clams, seagrasses, and microbial communities in marine sediments. A population of the lucinid clam, Stewartia floridana, was sampled from a subtidal seagrass bed at Bokeelia Island Seaport in Florida to test the hypotheses: (1) S. floridana, like other lucinids, are more abundant in seagrass beds than bare sediments; (2) S. floridana gill microbiomes are dominated by one bacterial operational taxonomic unit (OTU) at a sequence similarity threshold level of 97% (a common cutoff for species level taxonomy) from 16S rRNA genes; and (3) the ...


Development And Evaluation Of Novel Vaccination Strategies For Campylobacter Control In Poultry, Xiang Liu Aug 2015

Development And Evaluation Of Novel Vaccination Strategies For Campylobacter Control In Poultry, Xiang Liu

Masters Theses

Chicken is the primary natural host of Campylobacter, the leading bacterial cause of human enteritis in the US and other developed countries. Thus, mitigation of Campylobacter in chicken using innovative approaches, such as vaccination, will have a significant impact on food safety and public health. Our previous studies have demonstrated that the two outer membrane proteins, CmeC (the essential component of the CmeABC multi-drug efflux pump) and CfrA (a ferric enterobactin receptor), are feasible candidates for immune intervention against Campylobacter. DNA vaccine has appeared to offer various advantages for poultry, particularly when combined with in ovo vaccination. Chitosan-encapsulated subunit vaccines ...


The Human Intruder Test: An Anxiety Assessment In Rhesus Macaques (Macaca Mulatta), Emily J. Peterson Jan 2015

The Human Intruder Test: An Anxiety Assessment In Rhesus Macaques (Macaca Mulatta), Emily J. Peterson

Masters Theses

The human intruder test (HIT) is a noninvasive tool widely used for assessing anxiety in rhesus macaques (Macaca mulatta). This thesis explores the HIT procedure and applies it to a population of monkeys with a self-injurious behavioral pathology. Individual variation on this test can be used to assess anxiety and temperament. The first experiment of this thesis applied two different procedures of the HIT to 17 monkeys at UMass. Monkeys displayed little response to the intruder, and no significant differences were detected for the two procedures. To determine whether these responses were unique to the UMass monkeys, their behavior was ...


Trophic Interactions In A Semiaquatic Snake Community: Insights Into The Structure Of A Floodplain Food Web, Cynthia M. Carter Jan 2015

Trophic Interactions In A Semiaquatic Snake Community: Insights Into The Structure Of A Floodplain Food Web, Cynthia M. Carter

Masters Theses

Food webs provide a useful conceptual framework for evaluating the relationships that exist within ecological systems. Characterizing the interactions within these webs can improve our understanding of how communities are structured and what mechanisms stabilize them. Untangling these interactions can be an intractable problem in complex systems and insights gained from conventional methods are often accompanied by inherent sources of bias. This study used stable isotope analysis, an alternative to traditional methods, to investigate the roles and relative contributions of consumers at the top of a food web to community structure and stability. I compared the niche parameters of five ...


Aspects Of The Trophic Ecology Of An Invertivorous Snake Community, Meagan Amanda Thomas Jan 2014

Aspects Of The Trophic Ecology Of An Invertivorous Snake Community, Meagan Amanda Thomas

Masters Theses

Understanding the significance of trophic links has been of interest to ecologists for decades, likely because food web studies have the potential to reveal a considerable amount of information in the fields of ecosystem and community ecology. Despite the intrinsic benefits that come from elucidating food web structures, doing so is often problematic because of the complex and dynamic nature of ecological communities. The dietary ecology of small-bodied invertivorous snakes remains relatively understudied compared to other snake species. Many of these species are abundant throughout their range, making them ideal organisms for studying community-level questions. I employed a combination of ...


Geographic Variation In The Lower Temperature Tolerance In The Invasive Brown Anole, Anolis Sagrei And The Native Green Anole, Anolis Carolinensis (Sauria: Polychrotidae), Laura Carolina Maria Rubio Dec 2012

Geographic Variation In The Lower Temperature Tolerance In The Invasive Brown Anole, Anolis Sagrei And The Native Green Anole, Anolis Carolinensis (Sauria: Polychrotidae), Laura Carolina Maria Rubio

Masters Theses

Invasive species are considered to be the second greatest threat to native biodiversity and several factors have been identified as contributing to the success of introduced species, including their initial genetic variation and the ability of populations to adapt to a new environment. Temperature has a significant impact on reptilian ecology and distribution since they ordinarily rely on external heat sources for the maintenance of body temperatures suitable for normal activity. Body temperature affects performance in these organisms given its importance for all aspects of behavior, locomotion, courtship and rates of feeding and growth. Critical thermal tolerances can, therefore, give ...


Identifying The Spatial Distribution Of Three Plethodontid Salamanders In Great Smoky Mountains National Park Using Two Habitat Modeling Methods, Matthew Stephen Kookogey May 2012

Identifying The Spatial Distribution Of Three Plethodontid Salamanders In Great Smoky Mountains National Park Using Two Habitat Modeling Methods, Matthew Stephen Kookogey

Masters Theses

The main objective was to create habitat models of three plethodontid salamander species (Desmognathus conanti, D. ocoee, and Plethodon jordani) in GSMNP. To investigate the relationships between salamanders and their habitats, I used three models—logistic regression with use-availability sampling, logistic regression with case-control sampling, and Mahalanobis distance (D2)—for each species to gain a robust view of the relationships. The secondary objective was to compare the different modeling methods within and across the three species. Elevation was the dominant variable for all three species.

D2 for D. conanti predicted low elevations, close proximity to streams, metasandstones, and ...


An Evaluation Of Population Estimators And Forage Availability And Nutritional Quality For White-Tailed Deer In Tennessee, Jared Tyler Beaver Dec 2011

An Evaluation Of Population Estimators And Forage Availability And Nutritional Quality For White-Tailed Deer In Tennessee, Jared Tyler Beaver

Masters Theses

Given the white-tailed deer’s (Odocoileus virginianus; deer) popularity and potentially negative impact on forested systems; Arnold Air Force Base (AAFB) in Tullahoma, Tennessee, USA has made minimizing negative deer impacts on biodiversity a priority. To address these management issues, I initiated a study on AAFB to investigate deer survey techniques and the effects of deer density on forage availability across vegetative communities.

Current use of infrared-triggered cameras (camera) for estimating deer populations does not provide a measure of precision critical for density estimation. I conducted a camera survey for deer in Wildlife Management Area (WMA) Units 1 and 2 ...


Capture-Recapture Of White-Tailed Deer Using Dna Sampling From Fecal Pellet-Groups, Matthew James Goode Dec 2011

Capture-Recapture Of White-Tailed Deer Using Dna Sampling From Fecal Pellet-Groups, Matthew James Goode

Masters Theses

Reliable density estimates of game and keystone species such as white-tailed deer (Odocoileus virginianus) are desirable to set proper management strategies and for evaluating those strategies over time. However, traditional methods for estimating white-tailed deer density have been inhibited by behavior, densely forested areas that can hamper observation (detection), and invalid techniques of estimating effective trapping area. We wanted to evaluate a noninvasive method of mark-recapture estimation using DNA extracted from fecal pellets as the individual marker and for gender determination, coupled with a spatial detection function to estimate density (Spatially Explicit Capture-Recapture, SECR). We collected pellet groups from 11 ...


Impacts Of Predation Risk And Development On Susceptibility Of North American Anurans To Ranaviruses, Nathan Alden Haislip Dec 2010

Impacts Of Predation Risk And Development On Susceptibility Of North American Anurans To Ranaviruses, Nathan Alden Haislip

Masters Theses

For over three decades, amphibian populations have been declining across the globe. Emerging infectious diseases are responsible for some of these declines. Ranaviruses have caused die-offs in wild amphibian populations on 4 continents, in 5 Canadian provinces, and in over 25 U.S. states. In order to understand host-pathogen dynamics, it is critical to establish baseline information on species susceptibility and the effects of natural stressors. The goal of my thesis research was to quantify the effects of anuran development and exposure to invertebrate predators on species-specific susceptibility to ranavirus. My experiments were designed in factorial arrangements, and consisted of ...


Four Aspects Of Dogwood Pollination: Insect Visitation, A Novel Approach To Identify Pollen, Floral Volatile Emission, And Tracking Parentage, Paul Raymond Rhoades Aug 2010

Four Aspects Of Dogwood Pollination: Insect Visitation, A Novel Approach To Identify Pollen, Floral Volatile Emission, And Tracking Parentage, Paul Raymond Rhoades

Masters Theses

Part 1: Visitation of potential pollinators to Cornus florida and C. kousa flowers was assessed in East Tennessee in 2008 and 2009. Data regarding insect visitation rates to multiple trees per location were gathered throughout the flowering period. Diurnal and seasonal variations in visitation were recorded. Pollen coverage was assessed on portions of captured insect exoskeletons that were most likely to contact the stigma. Eleven families in four insect orders were collected from C. florida and 26 families in five orders from C. kousa. The most important pollinators in eastern Tennessee were bees in the Andrenidae and Halictidae. The most ...


Aging Coyotes Using Dental Characteristics, Michelle Maher Jan 2002

Aging Coyotes Using Dental Characteristics, Michelle Maher

Masters Theses

The accepted methods of age determination in the coyote (Canis latrans) are either highly subjective and unquantifiable or expensive and require the extraction of the canine tooth. Since neither of these methods are ideal, their limitations have impeded research on this species. Therefore, it was my objective to (1) develop and test the accuracy and precision of a descriptive key based on tooth wear patterns on the lower canine tooth, (2) develop and test the reliability of multiple regression models for aging coyotes using measurements from extracted teeth, and (3) suggest criteria for improving the consistency of results using these ...


Colony Composition And Demographics Of Beavers In Illinois, Stanley T. Mctaggart Jan 2002

Colony Composition And Demographics Of Beavers In Illinois, Stanley T. Mctaggart

Masters Theses

Beavers (Castor canadensis) have been extensively studied throughout North America, but little research has been conducted on this species in Illinois and the Midwest. Beavers exhibit wide variations in colony composition and demographics over their broad geographic range, so regional research is important for sound management. The objectives of this study were to investigate the: (1) typical composition of beaver colonies in Illinois; (2) reproductive potential of female beavers in Illinois; (3) sex-age composition of beaver populations in Illinois; and (4) efficacy of night-vision surveys versus removal trapping for estimating colony size. This study was conducted during the 1999-00 and ...


The Effect Of Predator Chemical Cues And Conspecific Alarm Signals Upon Behavior In Early And Late Developmental Stages Of American Toad (Bufo Americanus) Tadpoles, Carol Lynette Johnson Jan 2000

The Effect Of Predator Chemical Cues And Conspecific Alarm Signals Upon Behavior In Early And Late Developmental Stages Of American Toad (Bufo Americanus) Tadpoles, Carol Lynette Johnson

Masters Theses

The chemosensory capability and subsequent habitat choice of larval American toad (Bufo americanus) tadpoles were quantified using choice of refuge with both early and late developmental stages. Treatments were performed with two tadpole densities to ascertain the effect of social aggregations upon behavior. Bluegill (Lepomis macrochirus) and predaceous diving beetle larvae (Dytiscus sp.) predators were used to condition water. Conspecific tadpoles as well as Southern leopard frog (Rana sphenocephala) tadpoles were used to prepare treatment extracts.

Tadpole density (n=10 and n=20) had no significant effect upon the percentage of tadpoles seeking cover in any treatment. The percentage of ...


Distribution Of Fishes And Changes In Biotic Integrity In The New River, Tennessee, R. Brian Evans May 1998

Distribution Of Fishes And Changes In Biotic Integrity In The New River, Tennessee, R. Brian Evans

Masters Theses

Electrofishing samples of fishes were obtained from forty-two localities in the New River system, Tennessee during summer and fall 1996. Eight of forty-two species collected represent new records from the New River: Notropis telescopus, Moxostoma macrolepidotum breviceps, M. carinatum, Lepomis auritus, L. gulosus, L. microlophus, Etheostoma cinereum, and Stizostedion vitreum. Temporal changes in the distribution of fishes were detected by comparing historical collection records with fish samples from 1996. Older records were also employed in the compilation of a modified index of biotic integrity (IBI) that was used to assess changes in fish assemblage health during the past twenty years ...


Heartworm And Lungworms In Illinois' Canids And Their Possible Effect On Coyote Condition And Reproduction, David G. Gregory Jan 1998

Heartworm And Lungworms In Illinois' Canids And Their Possible Effect On Coyote Condition And Reproduction, David G. Gregory

Masters Theses

This study focuses on the prevalence of heartworm and lungworms in Illinois' canid species, and the effect that they may have on condition (body weight, kidney fat, marrow fat) and reproduction (placental scars) on coyote populations. A total of 1,150 coyotes (Canis latrans), 2,269 domestic dogs, 47 red foxes (Vulpes vulpes), and 2 gray foxes (Urocyon cinereoargenteus) were examined. Prevalence of heartworms (Dirofilaria immitis) averaged 17.8% in coyotes, 3.0% in domestic dogs, 2.0% in red foxes, and 0% in gray foxes. Domestic dogs not receiving any type of prophylactic treatment had a higher prevalence (12 ...


A Comparison Of Predation Rates On Real And Artificial Nests Of Grassland Birds, William B. Davison Jan 1998

A Comparison Of Predation Rates On Real And Artificial Nests Of Grassland Birds, William B. Davison

Masters Theses

I compared rates of predation between real and artificial nests of grassland birds in order to test the impact of nest type, nest position, and egg size on predation rates. I distributed wicker avicultural baskets and realistic grass nests baited with a clay egg and either northern bobwhite (Colinus virginianus) or house sparrow (Passer domesticus) eggs in four Conservation Reserve Program (CRP) grasslands in east-central Illinois. Nest success averaged 86.5% for 12 days of exposure for artificial nests. For real nests, nest success was markedly lower; averaging 39% over the entire nesting cycle and 59% during approximately 12 days ...


Caloric Production Of Black Bear Foods In Great Smoky Mountains National Park, Robert Michael Inman Dec 1997

Caloric Production Of Black Bear Foods In Great Smoky Mountains National Park, Robert Michael Inman

Masters Theses

Understanding energetic potential of habitat patches is important for management designed to provide adequate habitat for wildlife species. Great Smoky Mountains National Park (GSMNP) has a high density of black bears that have been studied intensively from 1968-1997; habitats within the Park are relatively undisturbed, and similar vegetative cover types can be found throughout the southern Appalachian mountains. Black bear reproduction in the Park has been correlated to hard mast production, however little work has been done to assess the importance of soft mast. Geographic Information System (GIS) based habitat use models have been developed for bears in the Park ...


Fish Fauna Of The Upper Cumberland River Drainage In Tennessee, John T. Baxter Dec 1997

Fish Fauna Of The Upper Cumberland River Drainage In Tennessee, John T. Baxter

Masters Theses

This thesis reports the findings of an ichthyofaunal survey of the upper Cumberland River drainage in Scott, Campbell, and Claiborne counties, Tennessee. This drainage lies on the Cumberland Plateau in northeastern Tennessee and has been impacted by extensive coal mining activity in the region. Present in the drainage are five listed species of primary concern to this study, Phoxinus cumberlandensis, Ericymba buccata, Notropis rubellus rubellus, Etheostoma baileyi, and Etheostoma sagitta. An additional species found in this drainage, Etheostoma nigrum susanae, is being considered for protected status. Field work for this survey was conducted mainly during May-August 1996 and May-August 1997 ...


Comparisons Of Genetic Variance And Physiological Responses In Two Populations Of Western Mosquitofish, Gambusia Affinis, Brett Egger Jan 1997

Comparisons Of Genetic Variance And Physiological Responses In Two Populations Of Western Mosquitofish, Gambusia Affinis, Brett Egger

Masters Theses

The study was conducted to determine the effects of lowered genetic variance in the Western mosquitofish (Gambusia affinis) on the physiological parameters of critical thermal maximum and minimum pH. Mosquitofish were obtained from two small central Illinois ponds, Lost Pond and Shadow Pond, by seines and dip nets. Once caught, fish were returned to the laboratory and acclimated for a minimum of five days at a temperature of 27°C and a pH of 8.25. At the beginning of each experimental run, fish were subjected to the physiological experiments for determination of critical thermal maximum and minimum pH, and ...


The Effects Of Habitat Fragmentation And Factors Influencing Nest Box Use On The Southern Flying Squirrel (Glaucomys Volans) In Southern Illinois, Catherine J. Woodworth Jan 1997

The Effects Of Habitat Fragmentation And Factors Influencing Nest Box Use On The Southern Flying Squirrel (Glaucomys Volans) In Southern Illinois, Catherine J. Woodworth

Masters Theses

I studied the effects of habitat :fragmentation on the southern flying squirrel (Glaucomys volans) in 30 forest fragments in southern Illinois. The fragments ranged in size from 6 ha to 5264 ha, and had varying degrees of isolation. I placed 10 nest boxes in each habitat fragment and checked them monthly. I captured southern flying squirrels in 24 of the 30 fragments, and found evidence of squirrels (i.e., nests and feeding stations) in 4 additional fragments. Thus, only 2 fragments did not show any evidence of squirrel use suggesting that the southern flying squirrel may not be particularly sensitive ...


Transfer Of Immunity Against Hymenolepis Diminuta Parasites In Mice, Jerome F. Atta-Fynn Jan 1997

Transfer Of Immunity Against Hymenolepis Diminuta Parasites In Mice, Jerome F. Atta-Fynn

Masters Theses

The potential transfer of resistance against the rat tapeworm, Hymenolepis diminuta, from adult BALB/c mice to their young, was tested by comparing the worm burdens of 24 experimentally infected pups from previously infected females to 14 experimentally infected pups from uninfected females. The mean number of worms recovered, mean weight of recovered worms and frequency of mice pups with eggs of the parasite in their feces were significantly lower in infected pups from infected mothers than in infected pups from uninfected mothers. The lower worm burden observed in the infected pups from infected mothers suggested that the resistance to ...


Roost Site Selection Of The Red Bat (Lasiurus Borealis), Kenneth J. Mager Jan 1997

Roost Site Selection Of The Red Bat (Lasiurus Borealis), Kenneth J. Mager

Masters Theses

I monitored the roosting activity and evaluated roost site selection of red bats (Lasiurus borealis) at study sites in Coles County during the summer of 1996. Red bats were mist-netted and radio transmitters were affixed to 12 individuals. A total of 105 transmitter-days were recorded with 75 roost locations identified. The roost types consisted of eight different species of trees, prairie grass, and residential structures but the vast majority of roosts (92%) were in large, deciduous trees. The height of the roosts ranged from 0.5 to 21.4 m, but 54.7% were between 5-10 m. Movement between consecutive ...


Ecology And Community Relationships Of The River Cooter, Pseudemys Concinna In A Southern Illinois Backwater, Michael J. Dreslik Jan 1996

Ecology And Community Relationships Of The River Cooter, Pseudemys Concinna In A Southern Illinois Backwater, Michael J. Dreslik

Masters Theses

In Illinois the River cooter, Pseudemys concinna, is an enigmatic endangered species. Even throughout its range, ecological studies on the River cooter are rare. During 1994 and 1995 I quantified the: growth rates and trends, population size and structure and dietary habits of a population from floodplain lake in Gallatin county, Illinois. Population estimation (Schnabel method) predicted 136 individuals at a density of 4.6 turtles/ha with a biomass of 3.6 Kg/ha. The sex ratio is slightly male biased (1:1.14). From back-calculated growth data, the von Bertalanffy growth model (Fabens' method) estimates males with a ...


Parental Investment In The Red-Eared Slider Turtle, Trachemys Scripta, Michael D. Marlen Jan 1996

Parental Investment In The Red-Eared Slider Turtle, Trachemys Scripta, Michael D. Marlen

Masters Theses

This study was conducted to determine egg and hatchling components of the red-eared slider (Trachemys scripta). In addition, energy components transferred from egg to hatchling were used to determine the level of parental investment in embryogenesis and hatchling care. Eggs of the red-eared slider, collected from central Illinois ponds, were obtained by inducing gravid females to lay by an injection of oxytocin. Egg and hatchling lipids were extracted with petroleum ether while egg and hatchling protein content was determined using the micro-Kjeldahl procedure. Eggs averaged 70.7% water by mass, and dry mass of whole eggs and egg yolks averaged ...


A Repeatable, Visual Survey Of Three Rare Percina (Osteichthyes: Percidae) Fish In Little River, Blount County, Tennessee, Charles H. Heacock Aug 1995

A Repeatable, Visual Survey Of Three Rare Percina (Osteichthyes: Percidae) Fish In Little River, Blount County, Tennessee, Charles H. Heacock

Masters Theses

A recent apparent decline of the darter species in Little River, Blount County, Tennessee, suggested a deterioration on habitat quality was taking place. The objective of this study was to establish a baseline of the abundance and distribution of three large and easily recognized darter species (Percina aurantiaca, P. burtoni, and P. macrocephala) believed to be very pollution intolerant.

The study area included 27 river miles with 20 accessible sites which were determined by an area reconnaissance. Each site has been described, including diagrams and photographs, and was surveyed six times between July and October 1993. A review of published ...