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Full-Text Articles in Ecology and Evolutionary Biology

Parasite Infection Mediates Trait Tradeoffs In Fundulus Heteroclitus, Sarah Dunn May 2015

Parasite Infection Mediates Trait Tradeoffs In Fundulus Heteroclitus, Sarah Dunn

Honors College Theses

To be successful, an animal must eat, grow, and reproduce. With limited resources, there are tradeoffs between these critical life history parameters but the direction of the tradeoffs is largely unknown in a changing environment. To determine whether environmental context affects life-history tradeoffs, I surveyed and quantified investment into reproduction, growth, and a proxy for immunity (parasitism), in the mummichog, Fundulus heteroclitus, a common inhabitant of salt marshes in Georgia. Three salt marsh sites along coastal Georgia (Shellman Bluff, Skidaway Island, and Tybee Island) were selected using a proxy for anthropogenic disturbance (impervious surface), which also fell along a …


The Reproductive Ecology Of The Timber Rattlesnake, Crotalus Horridus, In Northwestern Arkansas: Interactions Between Environment, Steroid Hormones, And Life History, Craig Michael Lind May 2015

The Reproductive Ecology Of The Timber Rattlesnake, Crotalus Horridus, In Northwestern Arkansas: Interactions Between Environment, Steroid Hormones, And Life History, Craig Michael Lind

Graduate Theses and Dissertations

In this dissertation I examined the relationship between individual energetic status, hormone production, and life history trait expression in field-active Timber Rattlesnakes, Crotalus horridus. In chapter one I reviewed what is known regarding these relationships in snakes and defined major research goals. In chapter two I described the seasonal profile of testosterone (T) and corticosterone (CORT) in relation to the breeding season and to individual energetic status in males. Results showed that the seasonal pattern of T production in C. horridus was different than other pit viper species with similar mating patterns. Testosterone was elevated in the months leading up …


Evolution, Systematics & Geographic Parthenogenesis Of Ilyodromus (Crustacea, Ostracoda), Rylan James Shearn Jan 2015

Evolution, Systematics & Geographic Parthenogenesis Of Ilyodromus (Crustacea, Ostracoda), Rylan James Shearn

Theses

Most multicellular organisms reproduce sexually at some point in their life cycle. This is paradoxical because being asexual is theoretically far more advantageous. Asexual organisms do not need to find and court new mates, they reproduce at a faster rate, and with no males, all members of the population contribute toward population growth rate. With over 20, often mutually exclusive hypotheses, this paradox resists a synthesised explanation, and continues to represent one of the largest gaps in our understanding of fundamental evolutionary theory. Clearly, more real world studies are required that document the selective mechanisms underlying differences in evolutionary fitness …


Reproductive Biology Of Syntopic Blackside Dace And Southern Redbelly Dace In Two Kentucky Streams, Brajaan Hayes Jan 2015

Reproductive Biology Of Syntopic Blackside Dace And Southern Redbelly Dace In Two Kentucky Streams, Brajaan Hayes

Online Theses and Dissertations

When a rare endemic species and an ecologically similar, but more cosmopolitan species share habitat, understanding how they interact with each other is important for conservation efforts. This is especially true if both species rely on the same spawning habitat, which could potentially lead to competitive displacement or hybridization. It is known that the federally threatened Blackside Dace and common Southern Redbelly Dace are ecologically similar species, occur syntopically in Kentucky in the upper Cumberland River basin, and utilize some of the same host species for nest sites; however, it is unclear if the two fish species are spawning site …


Fear Effects On Pheasant Reproductive Ecology And A Curriculum To Teach Wildlife Habitat Selection, Jessica Laskowski Apr 2014

Fear Effects On Pheasant Reproductive Ecology And A Curriculum To Teach Wildlife Habitat Selection, Jessica Laskowski

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

Predation risk is an important source of selection that shapes prey density, distribution and abundance. The immediate impacts of predator consumption on prey populations are widespread and well-studied, and a growing body of research demonstrates immediate impacts of predator-induced fear (independent of prey mortality) on prey behavior, physiology and life-history expression. However, predation risk is often seasonally variable and while it is clear that consumption effects often carry over to influence prey population demography for years after predators have disappeared, the temporal carry-over effects of fear on prey populations remain largely unexplored. We assessed effects of fall hunting activity by …


Comparison Of The Effects Of Toxic Cyanobacteria On The Reproductive Success Of Eurytemora Affinis Populations In The Baltic Sea And Green Bay, Wisconsin, Amanda Dwyer May 2013

Comparison Of The Effects Of Toxic Cyanobacteria On The Reproductive Success Of Eurytemora Affinis Populations In The Baltic Sea And Green Bay, Wisconsin, Amanda Dwyer

Lawrence University Honors Projects

The Northern Baltic Sea, off the southern coast of Finland, and Green Bay, off Lake Michigan in Wisconsin, both experience large toxic cyanobacteria blooms, especially during the summer and early fall months. Nodularia spumigena is the toxic algae in the Baltic Sea and produces the toxin Nodularin. Nodularin is a toxin that has branched from the toxin Microcystin, which is produced by Microcystis, the toxic algae forming blooms in Green Bay. While the toxin often acts as a defense mechanism to deter zooplankton from grazing, the calenoid copepod Eurytemora affinis, with populations in both the Baltic and Green Bay, …


The Population Dynamics Of Two Rodents In Two Coastal Marshes In Virginia, Robert K. Rose, John A. March Jan 2013

The Population Dynamics Of Two Rodents In Two Coastal Marshes In Virginia, Robert K. Rose, John A. March

Virginia Journal of Science

The communities of small mammals were evaluated for 13 months with capture-mark-recapture methods in two Spartina-Juncus marshes of the Atlantic coast in Northampton County, Virginia. Small mammals were trapped for three days each month using live traps placed on floats on two study grids. Two rodents were numerically dominant (~90% of small mammals) there: marsh rice rat, Oryzomys palustris, and meadow vole, Microtus pennsylvanicus. Monthly estimates of population density were greater for rice rats (peak: 45/ha) than for those of meadow voles (peak: 30/ha). Survival rates were generally low, especially for rice rats, indicating highly vagile populations. Both …


Reproduction And Population Characteristics Of White-Tailed Jackrabbits In South Dakota, Charles Dieter, Dustin Schaible Apr 2012

Reproduction And Population Characteristics Of White-Tailed Jackrabbits In South Dakota, Charles Dieter, Dustin Schaible

Great Plains Research: A Journal of Natural and Social Sciences (through 2013)

We evaluated the reproductive biology of314 white-tailed jackrabbits (Lepus townsendii) in 44 counties throughout South Dakota from June 2004 to September 2005. We classified jackrabbits as juveniles or adults based on the closure of the proximal epiphysis of the humerus using X-ray analysis. We determined annual reproductive activity through fluctuations in measured weights of reproductive organs for both sexes. The 2005 breeding season started in late February and proceeded until mid-July, approximately 142 days, allowing for females to potentially produce 3.3 litters. We found four distinct breeding periods by the overlap of estimated conception and parturition dates. Mean …


Assessing The Link Between Coastal Development And The Quality Of Fish Habitat In Mangrove Tidal Tributaries, Justin Micheal Krebs Mar 2012

Assessing The Link Between Coastal Development And The Quality Of Fish Habitat In Mangrove Tidal Tributaries, Justin Micheal Krebs

USF Tampa Graduate Theses and Dissertations

To assess the potential influence of coastal development on the quality of estuarine habitat for nekton, we characterized land use and the intensity of land development surrounding small tidal tributaries of Tampa Bay. Based on this characterization, we classified tributaries as undeveloped, industrial, urban or man-made (i.e., mosquito-control ditches). Over one-third (37%) of tributaries were determined to be heavily developed, while fewer than one-third (28%) remain relatively undeveloped. We then examined the nekton community from eleven tributaries in watersheds representing the defined land-use classes. Whereas mean nekton density and species richness were both independent of land use, nekton-community structure differed …


Humane Cat Population Management Guidance, International Companion Animal Management Coalition Jan 2011

Humane Cat Population Management Guidance, International Companion Animal Management Coalition

Stray and Feral Animal Populations Collection

The International Companion Animal Management Coalition has produced this document to provide government bodies and non-governmental organisations with a detailed resource to support them in their development and implementation of effective and humane programmes to manage cat populations.


A Comparison Of Prairie Vole Audible And Ultrasonic Pup Calls And Attraction To Them By Adults Of Each Sex, Thomas A. Terleph Jan 2011

A Comparison Of Prairie Vole Audible And Ultrasonic Pup Calls And Attraction To Them By Adults Of Each Sex, Thomas A. Terleph

Biology Faculty Publications

Rodent pups of many species emit both ultrasonic vocalizations (USVs) and calls spanning into a lower frequency range, audible to humans (AUDs), yet there has been little systematic comparison of these different call types, or analyses of how they might differ in signal function. Here the spectral and temporal characteristics of USV and AUD pup calls are described for the prairie vole (Microtus ochrogaster), a model used in studies of monogamous mating and biparental care, and a species with an unusually large functional and anatomical representation of auditory cortex. Findings provide a detailed description of each call type, …


Nest Desertion In A Reintroduced Population Of Migratory Whooping Cranes, Richard P. Urbanek, Sara E. Zimorski, Anna M. Fasoli, Eva K. Szyszkoski Jan 2010

Nest Desertion In A Reintroduced Population Of Migratory Whooping Cranes, Richard P. Urbanek, Sara E. Zimorski, Anna M. Fasoli, Eva K. Szyszkoski

Proceedings of the North American Crane Workshop

Reintroduction of an eastern migratory population of whooping cranes (Grus americana) into eastern North America began in 2001. Reproduction first occurred in 2005. Through 2008, eggs were produced in 22 first nests and 2 renests. All first nests failed–50% confirmed due to desertion by the parents and the remaining nest failures also consistent with the pattern of parental desertion. Nest failures were not related to stage of incubation, and they were often synchronous. Temperatures in winter and early spring affected timing of nest failure. An environmental factor such as harassment of incubating cranes by black flies (Simulium …


Survival, Reproduction, And Movements Of Migratory Whooping Cranes During The First Seven Years Of Reintroduction, Richard P. Urbanek, Lara E. A. Fondow, Sara E. Zimorski Jan 2010

Survival, Reproduction, And Movements Of Migratory Whooping Cranes During The First Seven Years Of Reintroduction, Richard P. Urbanek, Lara E. A. Fondow, Sara E. Zimorski

Proceedings of the North American Crane Workshop

An effort to reintroduce a migratory population of whooping cranes (Grus americana) into eastern North America began in 2001. During 2001-2007, 125 juveniles were costume/isolation-reared and released: 106 were led by ultralight aircraft from Necedah National Wildlife Refuge (NWR), central Wisconsin, to Chassahowitzka NWR, central Gulf Coast of Florida, on their first autumn migration (ultralight-led or UL). The remaining 19 individuals were released directly on Necedah NWR during autumn of the hatch year (direct autumn release or DAR). Of 86 UL and 13 DAR cranes that completed their first spring migration, 72 (84%) and 5 (38%), respectively, returned …


Reproductive Health And Performance Of The Florida Flock Of Introduced Whooping Cranes, Marilyn G. Spalding, Martin J. Folk, Stephen A. Nesbitt, Richard Kiltie Jan 2010

Reproductive Health And Performance Of The Florida Flock Of Introduced Whooping Cranes, Marilyn G. Spalding, Martin J. Folk, Stephen A. Nesbitt, Richard Kiltie

Proceedings of the North American Crane Workshop

We retrospectively examined the reproductive parameters of 122 breeding-age whooping cranes (Grus americana) in a reintroduced flock in central Florida from 1992 to 2007. The flock performed poorly when compared with an existing wild flock for all reproductive parameters when controlled for age. Pairs first formed in 1995, nested in 1999, and the first chick fledged in 2002. By 2007, 19 of 63 clutches produced 25 chicks, 9 of which fledged. Drought conditions were ruled out as the sole cause of failure when the drought lessened and productivity increased, but not in all years. We examined adult health, …


Observations Of Reproduction In Mountain Lions From Nebraska, Sam Wilson, Justin D. Hoffman, Hugh H. Genoways Jan 2010

Observations Of Reproduction In Mountain Lions From Nebraska, Sam Wilson, Justin D. Hoffman, Hugh H. Genoways

University of Nebraska State Museum: Mammalogy Papers

Occurrences of mountain lions (Puma concolor) in Nebraska have been steadily increasing; however, reproductive activity in mountain lions has not been documented in the state. We present the first evidence of mountain lion reproduction in Nebraska since mountain lions recolonized the state in the early 1990s. On 28 February 2007, a spotted kitten was hit by a vehicle in northwestern Nebraska; and based on body length and weight, we estimate its age at 3.9 months. On 20 December 2008, a female mountain lion and spotted kitten were photographed in the northwestern part of the state. On 9 May …


Changing Fecundity And Reproductive Output In Females Of A Chesapeake Bay Population Of Blue Crab, Callinectes Sapidus, Shannon L. Wells Jul 2009

Changing Fecundity And Reproductive Output In Females Of A Chesapeake Bay Population Of Blue Crab, Callinectes Sapidus, Shannon L. Wells

OES Theses and Dissertations

The Chesapeake Bay blue crab, Callinectes sapidus, is an important species both ecologically and as a fishery. Fishery dependent and independent data indicate that the population declined abruptly in the mid-1990s and has remained low. Previous work prior to the decline in population abundance found a significant relationship between size and fecundity for mature females. As with many heavily fished populations, this population has experienced a reduction in the size at maturity. The objectives of this study were to reassess the fecundity of the population, determine the lipid and protein energy allocated for reproduction, and to examine the concentrations …


Reproductive Tactics Of Aphidophagous Lady Beetles: Comparison Of A Native Species And An Invasive Species That Is Displacing It, Yukie Kajita Dec 2008

Reproductive Tactics Of Aphidophagous Lady Beetles: Comparison Of A Native Species And An Invasive Species That Is Displacing It, Yukie Kajita

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Coccinella septempunctata L. (Coleoptera: Coccinellidae) has been introduced to North America in recent decades, raising concerns of adverse impacts on native lady beetles, including the congeneric C. transversoguttata richardsoni (Brown). The central focus of my dissertation is to understand the importance of reproduction, in particular, in promoting invasion of C. septempunctata and its replacement of native lady beetles in alfalfa fields of western North America.

Studies were conducted to compare reproductive tactics of the invasive C. septempunctata and the native C. transversoguttata, by addressing: 1) maximum rate of reproduction of overwintered lady beetles, 2) population dynamics of the invasive …


Paddlefish Egg Deposition In The Lower Yellowstone River, Montana And North Dakota, Shannon E. Miller, Dennis L. Scarnecchia, Steven R. Fain Aug 2008

Paddlefish Egg Deposition In The Lower Yellowstone River, Montana And North Dakota, Shannon E. Miller, Dennis L. Scarnecchia, Steven R. Fain

The Prairie Naturalist

We used passive egg collectors during May, June, and July of2003 and 2004 in the lower 50 river kiiometers (rkm) of the Yellowstone River, eastern Montana and western North Dakota, to detect egg deposition by spawning paddle fish (Polyodon spathula). Sampling yielded 292 eggs (46 in 2003 and 246 in 2004). All egg collections in 2003 occurred on the descending limb of the spring hydrograph but 99% of egg collections in 2004 occurred before the spring hydrograph began to descend. Catch-per-unit-effort (CPUE) in 2004 was about four times that of 2003. A combination of river conditions, in addition …


Reproductive Health Of The Florida Flock Of Introduced Whooping Cranes, Marilyn G. Spalding, Martin J. Folk, Stephen A. Nesbitt Jan 2008

Reproductive Health Of The Florida Flock Of Introduced Whooping Cranes, Marilyn G. Spalding, Martin J. Folk, Stephen A. Nesbitt

Proceedings of the North American Crane Workshop

We examined the reproductive parameters of the introduced non-migratory flock of whooping cranes in Florida. Of 289 cranes introduced, 67 males and 65 females survived at least 3 years. The first behavioral pairs appeared in 1995, and eggs were first laid in 1999. In total, eggs were laid in 47 nests, 17 chicks hatched, and 4 young fledged by 2005. Severe drought conditions through 2001 were thought to be the reason for low reproductive nest success. In 2003 nesting conditions improved and 71% of nests with eggs, hatched chicks. During the next 2 years, with continued wet conditions, the proportion …


Survival, Movements, Social Structure, And Reproductive Behavior During Development Of A Population Of Reintroduced, Migratory Whooping Cranes, Richard P. Urbanek, Lara E. A. Fondow Jan 2008

Survival, Movements, Social Structure, And Reproductive Behavior During Development Of A Population Of Reintroduced, Migratory Whooping Cranes, Richard P. Urbanek, Lara E. A. Fondow

Proceedings of the North American Crane Workshop

An effort to reintroduce a migratory population of whooping cranes (Grus americana) into eastern North America began in 2001. During 2001-2004, 53 juveniles were released. All chicks were hatched at Patuxent Wildlife Research Center, Maryland, and transferred to Necedah National Wildlife Refuge (NWR), Wisconsin. Chicks were costume/isolation-reared and, with few exceptions, trained to follow ultralight aircraft, which led them to Chassahowitzka NWR, Central Gulf Coast of Florida. All individuals successfully returned to Central Wisconsin during their first spring migration except for the following: 5 individuals that were unable to navigate around Lake Michigan after taking an easterly migration …


A Sex Difference In Seasonal Timing Of Birth In A Livebearing Fish, Eric T. Schultz Jan 2008

A Sex Difference In Seasonal Timing Of Birth In A Livebearing Fish, Eric T. Schultz

EEB Articles

Sex differences in seasonal timing include differences in hatch- or birth-date distribution and differences in the timing of migration or maturation such as protandrous arrival timing (PAT), which is early male arrival at breeding sites. I describe a novel form of protandrous arrival timing, as a sex difference in birth-date distribution in a live-bearing fish (Dwarf Perch, Micrometrus minimus). In this species, birth coincides with arrival at breeding sites because newborn males are sexually active. A series of samples of pregnant females and young of year was collected in Tomales Bay, CA. I analyzed the daily age record in otoliths …


Phenotypic Plasticity Of Reproduction In Schizachyrium Scoparium (Poaceae) Populations In Relation To Ecological History, Elizabeth M. Obee, James A. Quinn Dec 2007

Phenotypic Plasticity Of Reproduction In Schizachyrium Scoparium (Poaceae) Populations In Relation To Ecological History, Elizabeth M. Obee, James A. Quinn

Aliso: A Journal of Systematic and Floristic Botany

Genetic differentiation in reproduction in the wide-ranging Schizachyrium scoparium (Poaceae) has been demonstrated in uniform gardens. However, the fine-tuning of flowering phenology and biomass allocation in relation to spatial and temporal fluctuations in the local environment is best accomplished by plastic responses to local variability. An earlier central New Jersey study suggested that S. scoparium populations in old fields of 2 to 40 years differed in plasticity. To test this apparent effect of ecological history on the development of different levels of plasticity, genotypes were collected from high- and low-fertility sites in New Jersey (forest biome) and in Oklahoma (grassland …


Spatial Scaling Of Avian Population Dynamics: Population Abundance, Growth Rate, And Variability, Jason Jones, Patrick J. Doran, Richard T. Holmes Oct 2007

Spatial Scaling Of Avian Population Dynamics: Population Abundance, Growth Rate, And Variability, Jason Jones, Patrick J. Doran, Richard T. Holmes

Dartmouth Scholarship

Synchrony in population fluctuations has been identified as an important component of population dynamics. In a previous study, we determined that local‐scale (<15‐km) spatial synchrony of bird populations in New England was correlated with synchronous fluctuations in lepidopteran larvae abundance and with the North Atlantic Oscillation. Here we address five questions that extend the scope of our earlier study using North American Breeding Bird Survey data. First, do bird populations in eastern North America exhibit spatial synchrony in abundances at scales beyond those we have documented previously? Second, does spatial synchrony depend on what population metric is analyzed (e.g., abundance, growth rate, or variability)? Third, is there geographic concordance in where species exhibit synchrony? Fourth, for those species that exhibit significant geographic concordance, are there landscape and habitat variables that contribute to the observed patterns? Fifth, is spatial synchrony affected by a species' life history traits? Significant spatial synchrony was common and its magnitude was dependent on the population metric analyzed. Twenty‐four of 29 species examined exhibited significant synchrony in population abundance: mean local autocorrelation (ρ) = 0.15; mean spatial extent (mean distance where ρ = 0) = 420.7 km. Five of the 29 species exhibited significant synchrony in annual population growth rate (mean local autocorrelation = 0.06, mean distance = 457.8 km). Ten of the 29 species exhibited significant synchrony in population abundance variability (mean local autocorrelation = 0.49, mean distance = 413.8 km). Analyses of landscape structure indicated that habitat variables were infrequent contributors to spatial synchrony. Likewise, we detected no effects of life history traits on synchrony in population abundance or growth rate. However, short‐distance migrants exhibited more spatially extensive synchrony in population variability than either year‐round residents or long‐distance migrants. The dissimilarity of the spatial extent of synchrony across species suggests that most populations are not regulated at similar spatial scales. The spatial scale of the population synchrony patterns we describe is likely larger than the actual scale of population regulation, and in turn, the scale of population regulation is undoubtedly larger than the scale of individual ecological requirements.


Age Structure And Reproductive Activity Of The Blue Sucker In The Milk River, Missouri River Drainage, Montana, Julie Bednarski, Dennis L. Scarnecchia Sep 2006

Age Structure And Reproductive Activity Of The Blue Sucker In The Milk River, Missouri River Drainage, Montana, Julie Bednarski, Dennis L. Scarnecchia

The Prairie Naturalist

The life history and ecology of the blue sucker (Cycleptus elongatus) in the lower Milk River, Montana were investigated in 2002 and 2003. A total of 253 blue sucker was captured; 248 adult fish, three larval fish, and two age-0 juveniles. The ages (n = 102) of the adult blue sucker ranged from 10 to 37 years; maximum age greatly exceeded ages reported in other studies. Blue sucker in the Milk River population grew slower, matured later, and lived longer than fish at lower latitudes. Adult females of the blue sucker were longer and weighed more than …


Reproductive Development In The Sicklefin Chub In The Missouri And Lower Yellowstone Rivers, Douglas J. Dieterman, Eric Roberts, Patrick J. Braaten, David L. Galat Jun 2006

Reproductive Development In The Sicklefin Chub In The Missouri And Lower Yellowstone Rivers, Douglas J. Dieterman, Eric Roberts, Patrick J. Braaten, David L. Galat

The Prairie Naturalist

We describe aspects of sicklefin chub (Macrhybopsis meeki) reproductive development from three study areas encompassing greater than 2,700 km of the Missouri and Lower Yellowstone rivers. The sicklefin chub was collected between late July and early October in 1996 and 1997. A total of 193 sicklefin chub was collected and examined for reproductive characteristics. Twenty-nine sicklefin chub were found to be reproductively mature females. Some sicklefin chub matured at age 2, but most matured at age 3 and all matured by age 4. Females first became mature at 70 to 79 mm total length (TL) in the Upper …


Decreased Reproductive Investment Of Female Threespine Stickleback Gasterosteus Aculeatus Infected With The Cestode Schistocephalus Solidus: Parasite Adaptation, Host Adaptation, Or Side Effect?, Eric T. Schultz, Michelle Topper, David C. Heins Jan 2006

Decreased Reproductive Investment Of Female Threespine Stickleback Gasterosteus Aculeatus Infected With The Cestode Schistocephalus Solidus: Parasite Adaptation, Host Adaptation, Or Side Effect?, Eric T. Schultz, Michelle Topper, David C. Heins

EEB Articles

Parasitic infections may cause alterations in host life history, including changes in reproductive investment (absolute amount of energy allocated to reproduction) and reproductive effort (proportion of available energy allocated to reproduction). Such changes in host life history may reflect: 1) a parasite tactic: the parasite adaptively manipulates energy flow within the host so that the host is induced to make a reduction in reproductive effort and reproductive investment, making more energy available to the parasite; 2) no tactic: there is no change in host reproductive effort and reproductive investment simply decreases as a side effect of the parasite depleting host …


The Ecology And Behaviour Of Varanus Mertensi (Reptilia: Varanidae), Phillip J. Mayes Jan 2006

The Ecology And Behaviour Of Varanus Mertensi (Reptilia: Varanidae), Phillip J. Mayes

Theses: Doctorates and Masters

This study examines numerous aspects of the ecology and behaviour of Merten's Water Monitor, Varanus mertensi (Reptilia: Varanidae) including; daily behaviour, diet, foraging behaviour, reproductive seasonality and daily and long-term movements. Findings from over two years of field study of V. mertensi found in waterbodies of both the Ord River Irrigation Scheme and surrounding East Kimberley/Victoria River Downs bioregion of Western Australia are presented. This study simultaneously broadens our understanding of the family Varanidae and provides insight into the life of a semi-aquatic faunal species found in waterbodies of the Ord River Irrigation Scheme.


Stochastic Dietary Restriction Using A Markov-Chain Feeding Protocol Elicits Complex, Life History Response In Medflies, James R. Carey, Pablo Liedo, Hans-Georg Müller, Jane-Ling Wang, Ying Zhang, Lawrence G. Harshman Feb 2005

Stochastic Dietary Restriction Using A Markov-Chain Feeding Protocol Elicits Complex, Life History Response In Medflies, James R. Carey, Pablo Liedo, Hans-Georg Müller, Jane-Ling Wang, Ying Zhang, Lawrence G. Harshman

Lawrence G. Harshman Publications

Lifespan in individually housed medflies (virgins of both sexes) and daily reproduction for females were studied following one of 12 dietary restriction (DR) treatments in which the availability of high-quality food (yeast–sugar mixture) for each fly was based on a Markov chain feeding scheme – a stochastic dietary regime which specifies that the future dietary state depends only on the present dietary state and not on the path by which the present state was achieved. The stochastic treatments consisted of a combination of one of four values of a ‘discovery’ parameter and one of three values of a ‘persistence’ parameter. …


Reproductive Ecology Of Two Common Woody Species, Juniperus Sabina And Artemisia Santolinifolia, In Mountain Steppes Of Southern Mongolia, Katrin Ronnenberg Jan 2005

Reproductive Ecology Of Two Common Woody Species, Juniperus Sabina And Artemisia Santolinifolia, In Mountain Steppes Of Southern Mongolia, Katrin Ronnenberg

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The present study describes the reproductive ecology of the prostrate shrub Juniperus sabina and the dwarf shrub Artemisia santolinifolia in dry mountain steppes of southern Mongolia. Whereas stands of the juniper are located at the drought limit of the genus’ distributional range, the genus Artemisia is typical of central Asian drylands. Both species produce large numbers of reproductive organs. For Juniperus sabina, however, only 2.5% of the morphologically intact seeds were found to be viable. Correspondingly, neither seedlings nor saplings were found in the field, and recruitment by reseeding happens at most rarely under the present climatic conditions.

Instead, …


Das Arteninventar Der Avifauna Der Mongolei Während Einer Nord-Süd-Durchquerung 1997, Tobias Stenzel, Michael Stubbe, R. Samjaa, Annegret Stubbe, C. Dulamsuren Jan 2005

Das Arteninventar Der Avifauna Der Mongolei Während Einer Nord-Süd-Durchquerung 1997, Tobias Stenzel, Michael Stubbe, R. Samjaa, Annegret Stubbe, C. Dulamsuren

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Here we present a detailed report on bird biodiversity of ecosystems along a North-South transect through Mongolia in 1997whic h serves as a guideline for further research projects and training for students in all Mongolian vegetation zones from northern steppes to southern deserts.

Two hundred fifty-five bird species were observed between 21st of July and 10th of August 1997. The main study sites were located in the North the Selenge-Orchon-basin with meadows and dune woodlands 15 km southern from Suchbaatar, the Middle Gobi-Aimag with desert steppes and sajrs (covered with Ulmus pumila) and in the Bordzongijn-gobi in the South …