Ecology and Evolutionary Biology Commons^™

First Results Of Wild Ass Research In The South Gobi Aymag/Mongolia In 2003 And 2004, Annegret Stubbe, Michael Stubbe, N. Batsajchan, R. Samjaa, S. Doržderem

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

The population of the Mongolian wild ass belongs to the nominate form Equus hemionus hemionus described by Pallas in 1775. This species is adapted to semidesert habitats in the Gobi region and is listed in the Red Book of Mongolia as well as on appendix I of the Washington Convention (CITES). Mapping of the northern border of the distributional range showed a remarkable decrease in size in comparison to the maps of Murzaev (1954) or Bannikov (1954). The pressure of civilization, settlements, motorization, and increasing numbers of domestic livestock in connection with the occupation of water resources and illegal hunting …

Zur Populationsökologie Und Raumnutzung Der Steppenwühlmaus Microtus Brandti (Radde, 1861) In Der Fortpflanzungsperiode, Ulrich Zöphel, N. Dawaa

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

During the growing season between 1988 and 1990 the population biology of Brandt’s vole (Microtus brandti) was observed in a population near Ulaanbaatar. Mark-recapture techniques (1,438 markings, 19,606 recaptures in total) and complementary methods were used. The density maximum was observed in July with 98 (1988); 169 (1989) and 94 (1990) individuals/ha and the population fluctuated by a factor of 7.4.

At the beginning of reproductive period the males disperse over a minimum distance of one female home range whereas the females do not migrate after winter. The typical mating system is promiscuity. Youngsters have been recorded from …

Natural History And Karyology Of The Yucatán Vesper Mouse, Otonyctomys Hatti, Hugh H. Genoways, Robert M. Timm, Mark D. Engstrom

University of Nebraska State Museum: Mammalogy Papers

Seventeen specimens of the rare Yucatán vesper mouse, Otonyctomys hatti, are now known from Belize, Guatemala, and the Mexican states of Campeche, Quintana Roo, and Yucatán. We herein report a second specimen of O. hatti, from Belize, extending the known geographic range of the species 95 km to the southeast in the country. This is the first location at which O. hatti has been taken sympatrically with the Central American vesper mouse, Nyctomys sumichrasti. We also report data on three additional specimens of O. hatti from Campeche. Nyctomys and Otonyctomys share similar habits and habitat requirements, and …

Effect Of Food Availability On Reproduction And Brood Size In A Freshwater Brooding Bivalve, Mark Beekey, Ronald H. Karlson

Biology Faculty Publications

Brood size is often constrained by the amount of energy available to produce offspring. Yet, energetic constraints may not be as important if the physical capacity to brood offspring is limited. Investigating the relative importance of energetic and physical constraints on brood size is necessary to understand how reproductive strategies are molded by natural selection. We investigated how food availability affects brood size in Sphaerium striatinum, a freshwater bivalve. We reared juveniles to adulthood under three food levels in a common garden experiment. The number of reproductive attempts, brood size, and stage of offspring development were measured. Clams reared …

Reproduction Of Black Drum, Pogonias Cromis, From The Chesapeake Bay Region, Brian K. Wells, Cynthia M. Jones

Virginia Journal of Science

Ovaries of black drum, Pogonias cromis, collected from the Chesapeake Bay region in 1992, were used to describe reproductive strategy and fecundity. Histological examination showed that black drum spawn in the Chesapeake Bay region from April through early June. Distributions of oocyte diameter showed distinct oocyte-developmental groups indicating that Chesapeake Bay black drum are group-synchronous batch spawners. Female black drum are extremely fecund ranging from 414,000 to 3,736,000 hydrated oocytes (mean = 1,389,000) per batch with a spawning periodicity of 3.8 days. Estimates of spawning strategy, spawning periodicity, and batch fecundity for black drum from the Chesapeake Bay region …

Aspects Of Reproduction And Pair Bonds In Florida Sandhill Cranes, Stephen A. Nesbitt, Martin J. Folk, Stephen T. Schwikert, James A. Schmidt

Proceedings of the North American Crane Workshop

From 1980-98 we captured and uniquely marked more than 400 Florida sandhill cranes (Grus canadensis prafensis). Age ratios of the marked population, excluding juveniles, was 66% adult and 33% subadult, and the sex ratio was 49% male and 51% female. Average clutch size for 210 nests checked from 1983-97 was 1.78 ± 0.18 (SD) and frequency of l-egg clutches varied among years. Average post-fledging brood size from 1991 to 1997 was 1.27 ± 0.17 (SD), included a 3-chick brood. Average percent ofYOlmg from 2 study areas, 1991-97 was 11.9 ± 3.23 (SD). We observed renesting up to 3 …

Leadership In Wolf, Canis Lupus, Packs, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

I examine leadership in Wolf (Callis lupus) packs based on published observations and data gathered during summers from 1986 to 1998 studying a free-ranging pack of Wolves on Ellesmere Island that were habituated to my presence. The breeding male tended to initiate activities associated with foraging and travel, and the breeding female to initiate, and predominate in, pup care and protection. However, there was considerable overlap and interaction during these activities such that leadership could be considered a joint function. In packs with multiple breeders, quantitative information about leadership is needed.

Lack Of Reproduction In Muskoxen And Arctic Hares Caused By Early Winter?, L. David Mech

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

A lack of young muskoxen (Ovibos moschatus) and arctic hares (Lepus arcticus) in the Eureka area of Ellesmere Island, Northwest Territories (now Nunavut), Canada, was observed during summer 1998, in contrast to most other years since 1986. Evidence of malnourished muskoxen was also found. Early winter weather and a consequent 50% reduction of the 1997 summer replenishment period appeared to be the most likely cause, giving rise to a new hypothesis about conditions that might cause adverse demographic effects in arctic herbivores.

Durant l’été 1998, et ce, à la différence de la plupart des années depuis …

The Annual Reproductive Cycle Of Oryzomys Palustris In A Virginia Tidal Marsh, Erin A. Dreelin

Biological Sciences Theses & Dissertations

The objectives of my study were to determine when the marsh rice rat (Oryzomys palustris) begins and ends reproduction during the year, if there are seasonal changes in litter size, and the weight at which sexual maturity is reached. Monthly samples of rice rats were trapped from May 1995 to May 1996 in Northampton County, Virginia. Rice rats were trapped with Fitch live traps, euthanized in the field, and brought to the lab for necropsy. Data from two other studies of rice rats in Northampton County were also examined. Potential breeders did not reproduce with equal intensity throughout the …

The Biological Flora Of Coastal Dunes And Wetlands. Sesuvium Portulacastrum (L.) L., Robert I. Lonard, Frank W. Judd

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Sesuvium portulacastrum (L.) L. (sea purslane, cenicilla) is a pantropical, perennial, trailing herb (Aizoaceae) with pink-purple or occasionally white flowers that grows on coastal beaches of five continents and many islands. Herein we present a review of the biology of S. portulacastrum. It is an important pioneer species on sandy beaches in the subtropics and tropics, where its stoloniferous, mat-forming growth habit promotes embryonic dune formation in belts parallel to the shoreline. Colonies act as barriers to intercept and hold water and wind transported sand. Sesuvium portulacastrum's success as a colonizing species is related, in large part, to its …

The Effect Of Disturbance On The Reproduction And Management Of Captive Cranes, Claire M. Mirande, James W. Carpenter, Ann M. Burke

Proceedings of the North American Crane Workshop

A retrospective analysis of egg laying histories and observations of crane pairs at the International Crane Foundation and the Patuxent Wildlife Research Center indicates that disturbance associated with captivity has adverse impacts on captive breeding. Females on public display laid significantly fewer eggs than those off display (P < 0.05). Crane pairs moved to other pens (other than adjacent pens) or hetween facilities laid slightly fewer eggs than those birds which were not moved. although the results were not statistically significant (P = 0.188). Pen design and construction also appeared to have adverse impacts on breeding. In addition, human activities, intraspecific interactions, and rearing methods influence a bird's response to disturbance, and, therefore, these factors must also be considered in an effective crane management program. Modifying procedures to minimize disturbance, timing necessary disturbances after the breeding and molt seasons, and carefully monitoring birds for signs of stress can result in increased reproductive potential for captive, endangered cranes.

Social Assemblages And Mating Relationships In Prairie Dogs: A Dna Fingerprint Analysis, Steven E. Travis, Con Slobodchikoff, Paul Kefan

Reproductive Behavior Collection

Mating system characterizations have been hindered by difficulties in accurately assigning parentage to offspring. We investigated the relationship between social assemblages and mating relationships in a territorial harem polygynous mammal, the Gunnison's prairie dog, using a combination of behavioral and molecular analyses. We demonstrate multiple paternity and an extraordinarily high incidence of extraterritorial fertilizations (i.e., 61% of all progeny), in combination with the existence of female kin groups. On this basis, we conclude that social assemblages alone provide a poor description of the Gunnison's prairie dog mating system, and suggest several potential reasons for the maintenance of territoriality in this …

Terrapene Carolina Carolina, Joseph C. Mitchell, Rafael O. De Sá

Biology Faculty Publications

TERRAPENE CAROLINA CAROLINA (Eastern Box Turtle). REPRODUCTION. Female Terrapene carolina containing oviductal eggs have been recorded in Virginia from 26 May to 25 July (Mitchell, in press. The Reptiles of Virginia. Smithsonian Inst. Press, Washington, D.C.). Other reports of reproduction in Terrapene (see list in Ernst and McBreen 1991. Cat. Amer. Amphib. Rept. 512.1-512.13) indicate that nesting occurs in late spring and early summer throughout its range.

An Analysis Of External Features As Predictors Of Reproductive Status In Small Mammals, Kenneth Wayne Mccravy

Biological Sciences Theses & Dissertations

Reproductive status in specimens of nine populations of seven species of small mammals was evaluated by examining the external reproductive features of nipple size, condition of the pubic symphysis, and vaginal condition and, in males, testis position. Usefulness of these external features in predicting true monthly breeding rates was evaluated by comparing predictions of breeding rates with true rates based on necropsy. Accuracy of predictions of reproductive status of individuals based on single external features and combinations of external features and body measurements was then analyzed at a finer level by comparing those predictions with results of necropsy of the …

The Water Vapor Conductance Of Squamate Reptilian Eggs: The Influence Of Scaling On Nesting Ecology., Louis A. Somma

Papers in Herpetology

Flexible-shelled eggs of squamate reptiles are strongly influenced by their surrounding microclimate, particularly the hydric conditions of the nest. The eggshell water vapor conductance of an egg can be an indication of its requirement for water from the nest. Ackerman et al. (1985. Physiol. Zool. 58:129-137) have described the scaling relationship for eggshell water vapor conductance (G_H2O) of flexible-shelled reptilian eggs (G_H2O = 981.8M^0.52). This scaling relationship was investigated with water vapor conductance data obtained from 8 species of lizards representing the families Iguanidae (Anolis carolinensis, A. sagrai, Sceloporus woodi, S. virgatus) …

Alloparental Care In The Prairie Skink, Eumeces Septentrionalis: A Case Of Mistaken Identity?, Louis A. Somma

Papers in Herpetology

Alloparental care , or one individual caring for the eggs or young of another , ha s been documented for a variety of verte brate organism s (Coyne & Sohn 1978; Frame et a1. 1983; Gowaty & Karlin 1984) . In t h i s a rticle I document an instance of alloparental care in the prairie skink , Eumeces septentrionalis .

Environmental Psychology And Great Ape Reproduction, Terry L. Maple

Zoos and Aquariums Collection

At the 1980 Great Ape Infertility Workshop, we concluded that "physical and social environments must be improved if not optimized if great apes are to reproduce satisfactorily ... " In 1982, the trend toward improvement continues and there are some promising signs that reproduction has been enhanced as predicted. The problem of designing and evaluating captive environments which will facilitate interaction, reproduction, appropriate parenting, and socialization is well within the scope of Environmental Psychology. I intend to illustrate the promise of this applied research field in the remarks that follow.

Contributions To The Reproductive Biology And Natural History Of The Pirateperch, Aphredoderus Sayanus, Edward O. Murdy

Biological Sciences Theses & Dissertations

The purpose of this study was to describe the micro and macro-anatomy of the reproductive system and the testicular and ovarian development in Aphredoderus sayanus.

Specimens were collected at least once a month from September, 1976, through May, 1977, in Cypress Pond, a part of the Dismal Swamp drainage, outside of Suffolk, Virginia. Forty-three specimens had their gonads examined histologically, of these 13 were males, 29 were females and in one specimen the sex was not determinable.

Aphredoderus sayanus is a spring spawner, spent gonads were found on and after April 13, 1977. Gonads began to ripen in the …

Reproduction And Hematology Of The Cache Elk Herd, Thomas B. Follis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The initial three years of a 10-year reproductive study of elk involved three major phases. A fourth was added because of convenience. Objective 1 was to ascertain pregnancy rates in yearling and mature elk by rectal palpation, associate these rates with subsequent fall cow/calf ratios, and to test concurrently an ultrasonic fetal heart detector. Rectally observed anatomical changes in gravid uteri of cattle were directly applicable to elk. Ultrasonic detections of pregnancies in elk and deer were unsuccessful.

Pregnancy rates in the 1969-70 winter of 100 and 0 percent, respectively, for 19 adult and five yearling elk were associated with …