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2008

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Articles 61 - 88 of 88

Full-Text Articles in Population Biology

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 …

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The Pollination Biology And Mating System Of A Peripheral Population Of Witheringia Solanacea (Solanaceae), Timothy Miller Jan 2008

The Pollination Biology And Mating System Of A Peripheral Population Of Witheringia Solanacea (Solanaceae), Timothy Miller

Honors Theses

Pollinator visitation rates over the life of a flower are determined by pollinator abundance and floral longevity. If flowers are not visited frequently enough, pollen limitation may occur, favoring the evolution of self-compatibility (SC). In plant species with varying SC levels, central populations often are self-incompatible (SI) and peripheral populations are SC. Witheringia solanacea (Solanaceae) is a species that follows this trend with the exception of one population in the Monteverde Cloud Forest Reserve, which is peripheral yet SI. I investigated this population using multiple techniques including floral bagging, pollinator observations, microsatellite analysis, and floral longevity manipulations. My results confirmed …

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Temporal Distribution Of Harvested Mid-Continent Sandhill Cranes Within The Central Flyway States During The 1997–2001 Hunting Seasons, Adrianna C. Araya, James A. Dubovsky Jan 2008

Temporal Distribution Of Harvested Mid-Continent Sandhill Cranes Within The Central Flyway States During The 1997–2001 Hunting Seasons, Adrianna C. Araya, James A. Dubovsky

Proceedings of the North American Crane Workshop

Since 1975, annual harvest estimates for Mid-Continent sandhill cranes (Grus canadensis) have been collected in all states for which a hunting season has been authorized by the U.S. Fish and Wildlife Service (Service). Although these data have been used to monitor the harvest of the Mid-Continent population, analyses to promote understanding of the temporal distribution of harvested sandhill cranes by individual states throughout the Central Flyway have not been conducted. For the 1997-2001 hunting seasons, we collected harvest questionnaires from 4,408 hunters in the Central Flyway who provided information about the date, location, and number of harvested sandhill …

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Is Magnitude Of Fat Storage By Spring-Staging Sandhill Cranes Declining In The Central Platte River Valley, Nebraska?, David A. Brandt, Gary L. Krapu Jan 2008

Is Magnitude Of Fat Storage By Spring-Staging Sandhill Cranes Declining In The Central Platte River Valley, Nebraska?, David A. Brandt, Gary L. Krapu

Proceedings of the North American Crane Workshop

Proximate analyses of carcasses of sandhill cranes (Grus canadensis) collected in the Central Platte River Valley (CPRV), Nebraska, during spring 1999 indicated a marked decline in fat levels from springs 1978 and 1979. Concern that amounts of fat cranes stored by their spring departures from the CPRV may have further declined prompted this evaluation. For our assessment, we made use of morphological measurements (culmen post nares, tarsus, flattened wing chord) along with body mass on each of 810 sandhill cranes that were collected for proximate analysis or captured with rocket nets at widely distributed sites in the CPRV during 1978-1979 …

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Hunting Success For Mid-Continent Sandhill Cranes In The Central Flyway: Comparing Current And Historic Results, James A. Dubovsky, Adrianna C. Araya Jan 2008

Hunting Success For Mid-Continent Sandhill Cranes In The Central Flyway: Comparing Current And Historic Results, James A. Dubovsky, Adrianna C. Araya

Proceedings of the North American Crane Workshop

Sport hunting for the Mid-continent population of sandhill cranes (Grus canadensis) in the United States resumed in New Mexico in 1961 after a 45-year moratorium. Interest in crane hunting continued to increase and by 1975, 8 states were participating in sandhill crane hunting. Currently, hunting seasons have been established in all Central Flyway states except Nebraska. Efforts to collect information on the annual harvest of sandhill cranes began in 1975 when hunters were required to obtain federal sandhill crane hunting permits. The permits included a hunting diary whereby hunters were asked to record information about their daily hunting …

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Feather Molt Of Nonmigratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Jeannette M. Parker, Marilyn G. Spalding, Stephen B. Baynes, Kristen L. Candelora Jan 2008

Feather Molt Of Nonmigratory Whooping Cranes In Florida, Martin J. Folk, Stephen A. Nesbitt, Jeannette M. Parker, Marilyn G. Spalding, Stephen B. Baynes, Kristen L. Candelora

Proceedings of the North American Crane Workshop

Molt patterns of wild whooping cranes (Grus americana) are largely unknown, and what knowledge we have has been based on scant data. We documented patterns of feather molt in nonmigratory whooping cranes in Florida during 1993-2005. All birds replaced flight feathers (remiges) in a synchronous (simultaneous) manner and spent time flightless. It took 38-46 days (mean = 44 days, n = 8) for feathers to regrow and birds to regain flight ability. When flightless due to remigial molt, cranes became more secretive and spent more time in wetlands during feather regrowth. Most (70%) whooping cranes first molted their …

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Factors Influencing Greater Sandhill Crane Nest Success At Malheur National Wildlife Refuge, Oregon, Gary L. Ivey, Bruce D. Dugger Jan 2008

Factors Influencing Greater Sandhill Crane Nest Success At Malheur National Wildlife Refuge, Oregon, Gary L. Ivey, Bruce D. Dugger

Proceedings of the North American Crane Workshop

We used logistic regression to model the effects of weather, habitat, and management variables on Greater Sandhill Crane (Grus canadensis tabida) nest success at Malheur National Wildlife Refuge in southeast Oregon. We monitored 506 nests over 9 breeding seasons. Mean apparent nest success was 72% ± 4% and varied from 51 to 87%. Nest success was lower one year after a field was burned and declined with nest initiation date. Nest success was higher during warmer springs, in deeper water, and in years with moderate precipitation. Haying, livestock grazing, and predator control did not influence nest success. We …

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Sandhill Crane Wintering Ecology In The Sacramento–San Joaquin Delta, California, Gary L. Ivey, Caroline P. Herziger Jan 2008

Sandhill Crane Wintering Ecology In The Sacramento–San Joaquin Delta, California, Gary L. Ivey, Caroline P. Herziger

Proceedings of the North American Crane Workshop

We studied wintering sandhill crane (Grus canadensis) ecology in 2002–2003 in the Sacramento-San Joaquin Delta of California, focusing on Staten Island, a corporate farm which was acquired by The Nature Conservancy and managed to promote sustainable agriculture that is beneficial to wildlife. Our purpose was to define habitat conservation needs for cranes, including the state-threatened greater subspecies (G. c. tabida). Research was conducted through intensive surveys by vehicle of crane foraging and roosting behavior. We estimated that about 1,500 greaters used Staten Island, which is a significant portion of the Central Valley Population of greater sandhill …

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Risk Factors Associated With Developmental Limb Abnormalities In Captive Whooping Cranes, Cristin Kelley, Barry K. Hartup Jan 2008

Risk Factors Associated With Developmental Limb Abnormalities In Captive Whooping Cranes, Cristin Kelley, Barry K. Hartup

Proceedings of the North American Crane Workshop

This retrospective survey identifies potential risk factors for developmental limb abnormalities in whooping crane (Grus americana) chicks reared at the International Crane Foundation between 1990 and 2006. We summarized a series of biologicallyrelevant pre- and post-hatch variables from this population using in-house aviculture and veterinary records, and then compared them between chicks with and without developmental carpal, toe and leg deformities. Chi-square analysis revealed associations between 1) rearing style and each type of deformity, 2) egg source and carpal and toe deformities, and 3) the pre-existence of a toe deformity and carpal and leg deformities. Multivariate analyses using …

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Habitat Characteristics Influencing Sandhill Crane Nest Site Selection, Anne E. Lacy, Su Liying Jan 2008

Habitat Characteristics Influencing Sandhill Crane Nest Site Selection, Anne E. Lacy, Su Liying

Proceedings of the North American Crane Workshop

The breeding population of greater Sandhill cranes (Grus canadensis tabida) in Wisconsin has greatly increased since the population was nearly extirpated in the mid-1930’s (Henika 1936). The International Crane Foundation (ICF) has been studying these birds for over 10 years in an area with one of the highest density of breeding cranes in the Midwest; we have calculated a nesting density of over 5 pairs/km2 (ICF unpublished data). Prior to this study, little was known about the habitat characteristics that may be influencing nest site selection. We conducted nest surveys by helicopter during the last week of April …

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Selection Criteria For Important Sites For Wintering Sandhill Cranes In The Mexican Altiplano, Alberto Lafon Terrazas, Eduardo Carrera Gonzalez Jan 2008

Selection Criteria For Important Sites For Wintering Sandhill Cranes In The Mexican Altiplano, Alberto Lafon Terrazas, Eduardo Carrera Gonzalez

Proceedings of the North American Crane Workshop

Conservation of natural resources has increased worldwide, and Mexico shows the same tendency. Unfortunately, selection criteria for conservation areas and objectives do not always follow a methodology that will allow for optimum selection. In Mexico and other countries we have a series of priority sites proposed by experts in various biodiversity areas, based on knowledge of the existing biological resources of the site. This results in two situations: more attention and resources are given to certain areas, but no resources are invested in sites that could be of equal or greater importance than those currently proposed. This leads to knowledge …

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Sandhill Crane Nest Habitat Selection And Factors Affecting Nest Success In Northwestern Minnesota, Stephen J. Maxson, John R. Fieberg, Michael R. Riggs Jan 2008

Sandhill Crane Nest Habitat Selection And Factors Affecting Nest Success In Northwestern Minnesota, Stephen J. Maxson, John R. Fieberg, Michael R. Riggs

Proceedings of the North American Crane Workshop

We studied 62 greater sandhill crane (Grus canadensis tabida) nests in northwestern Minnesota during 1989-1991 to document nest habitat use and selection, nest success, and factors associated with nest success. We recorded 15 habitat variables at each nest and at a randomly selected site in the same wetland. Nests were in basins 0.01-601 ha (Median = 2.2 ha) and at water depths 0-35.7 cm (Median = 9.7 cm). Cattail (Typha sp.) was the dominant vegetation at 58.0% of nests while 21.0% were at sites dominated by phragmites (Phragmites australis). Conditional logistic regression models indicated …

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Trends In Sandhill Crane Numbers In Eastern New Mexico, James B. Montgomery Jr. Jan 2008

Trends In Sandhill Crane Numbers In Eastern New Mexico, James B. Montgomery Jr.

Proceedings of the North American Crane Workshop

Following a 1980s decline in the number of cranes in the Bitter Lake National Wildlife Refuge area of the Pecos River Valley in eastern New Mexico, peak fall migration numbers increased from 5,640 in 1989-90 to 15,790 in 2003-04 and 13,650 in 2004-05. Concurrently, hectares of corn grown for silage to feed dairy cows increased from 1,781 in 1989 to 8,013 in 2003 and 7,325 in 2004. The population goals of the NM Department of Game and Fish are being met but a downturn in the dairy industry could result in a decline in crane numbers.

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Timing Of Molt In Florida Sandhill Cranes, Stephen A. Nesbitt, Stephen T. Schwikert Jan 2008

Timing Of Molt In Florida Sandhill Cranes, Stephen A. Nesbitt, Stephen T. Schwikert

Proceedings of the North American Crane Workshop

We observed feather molt in Florida sandhill cranes (Grus canadensis pratensis) between 1978 and 1997. We report data from 4 feather groups: remiges, rectrices, wing coverts and contour feathers. In all feather groups, the median date of ecdysis preceded endysis by about 30 days. Endysis in adults was generally later than it was in first- or second-year subadults. Remiges grew at a rate of 4.72 ± 1.56 SD mm per day. We estimated that primary and secondary wing feathers were usually regenerated within 45 to 70 days.

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Body Mass Index (Bmi) Of Normal Sandhill Cranes, Stephen A. Nesbitt, Marilyn G. Spalding, Kristen L. Candelora, Paul S. Kubilis, Stephen T. Schwikert Jan 2008

Body Mass Index (Bmi) Of Normal Sandhill Cranes, Stephen A. Nesbitt, Marilyn G. Spalding, Kristen L. Candelora, Paul S. Kubilis, Stephen T. Schwikert

Proceedings of the North American Crane Workshop

We used linear and mass measurements to construct a body mass index (BMI) for 2 subspecies of sandhill cranes (Grus canadensis). We found that BMI declined during the spring and early summer period. We used the BMI to show that juvenile Florida sandhill cranes (G. c. pratensis) reach their full mass at about 270 days of age, near the age at which they begin to leave the company of their parents. We used mensural data to predict a minimum expected mass for normal sandhill cranes which could be then used to evaluate the relative health of …

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Behavior Comparisons For Whooping Cranes Raised By Costumed Caregivers And Trained For An Ultralight-Led Migration, Glenn H. Olsen, John B. French Jan 2008

Behavior Comparisons For Whooping Cranes Raised By Costumed Caregivers And Trained For An Ultralight-Led Migration, Glenn H. Olsen, John B. French

Proceedings of the North American Crane Workshop

The successful reintroduction program being run by the Whooping Crane Eastern Partnership using whooping cranes (Grus americana) trained to fly behind ultralight aircraft depends on a supply of these trained crane colts each year. The crane colts are hatched from eggs contributed by the various partners and trained to follow costume clad humans and ultralight aircraft at USGS Patuxent Wildlife Research Center, Laurel, Maryland, USA. After several seasons of raising small numbers of crane colts (7-14), we wanted to increase the number of birds being trained, but were restrained by limits in our facilities. By altering the established …

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Safety Of West Nile Virus Vaccines In Sandhill Crane Chicks, Glenn H. Olsen, Kimberli J. Miller, Douglas E. Docherty, Valerie Bochsler Jan 2008

Safety Of West Nile Virus Vaccines In Sandhill Crane Chicks, Glenn H. Olsen, Kimberli J. Miller, Douglas E. Docherty, Valerie Bochsler

Proceedings of the North American Crane Workshop

West Nile virus arrived in North America in 1999 and has spread across the continent in the ensuing years. The virus has proven deadly to a variety of native avian species including sandhill cranes (Grus canadensis). In order to provide safe and efficacious protection for captive and released populations of whooping cranes (G. americana), we have conducted a series of four research projects. The last of these was a study of the effects of two different West Nile virus vaccines on young Florida sandhill crane (G. c. pratensis) chicks and subsequent challenge with the virus. …

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Use Of Clap Traps In Capturing Nonmigratory Whooping Cranes In Florida, Jeannette M. Parker, Martin J. Folk, Stephen B. Baynes, Kristen L. Candelora Jan 2008

Use Of Clap Traps In Capturing Nonmigratory Whooping Cranes In Florida, Jeannette M. Parker, Martin J. Folk, Stephen B. Baynes, Kristen L. Candelora

Proceedings of the North American Crane Workshop

Between March 2001 and April 2005 we captured 28 nonmigratory Florida whooping cranes (Grus americana) with clap traps. Out of the 6 different capture methods we employed, the clap trap accounted for 42% of our birds captured. Its ability to safely capture one crane or multiple cranes simultaneously, flexibility in size and placement, and low cost make it an important tool to facilitate transmitter replacements and health checks among the experimental Florida whooping crane population.

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A Low Intensity Sampling Method For Assessing Blue Crab Abundance At Aransas National Wildlife Refuge And Preliminary Results On The Relationship Of Blue Crab Abundance To Whooping Crane Winter Mortality, Bruce H. Pugesek, Michael J. Baldwin, Thomas V. Stehn Jan 2008

A Low Intensity Sampling Method For Assessing Blue Crab Abundance At Aransas National Wildlife Refuge And Preliminary Results On The Relationship Of Blue Crab Abundance To Whooping Crane Winter Mortality, Bruce H. Pugesek, Michael J. Baldwin, Thomas V. Stehn

Proceedings of the North American Crane Workshop

We sampled blue crabs (Callinectes sapidus) in marshes on the Aransas National Wildlife Refuge, Texas from 1997 to 2005 to determine whether whooping crane (Grus americana) mortality was related to the availability of this food source. For four years, 1997 - 2001, we sampled monthly from the fall through the spring. From these data, we developed a reduced sampling effort method that adequately characterized crab abundance and reduced the potential for disturbance to the cranes. Four additional years of data were collected with the reduced sampling effort methods. Yearly variation in crab numbers was high, ranging …

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Whooping Crane Collisions With Power Lines: An Issue Paper, Thomas V. Stehn, Tom Wassenich Jan 2008

Whooping Crane Collisions With Power Lines: An Issue Paper, Thomas V. Stehn, Tom Wassenich

Proceedings of the North American Crane Workshop

Collision with power lines is the greatest source of mortality for fledged whooping cranes (Grus americana) in the Aransas-Wood Buffalo population (AWBP) that migrate between the Northwest Territories, Canada to the Texas coast. This paper compiles 45 documented whooping crane mortalities from power line strikes in North America and provides known information on crane / power line interactions. A map of the AWBP whooping crane migration corridor was derived with 100 and 200-mile wide corridors delineated showing the location of known mortalities. Recommendations are provided to try to reduce this major threat facing whooping cranes.

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A Year-Long Study Of Food Consumption By Captive Whooping Cranes At The International Crane Foundation, Jessica J. Stocking, Michael S. Putnam, Nathanial B. Warning Jan 2008

A Year-Long Study Of Food Consumption By Captive Whooping Cranes At The International Crane Foundation, Jessica J. Stocking, Michael S. Putnam, Nathanial B. Warning

Proceedings of the North American Crane Workshop

Throughout 2002, we recorded daily food consumption by 12 pairs of captive whooping cranes (Grus americana). For 7 pairs we recorded food consumption throughout the entire year while there were large continuous gaps in measurements of food consumption for 5 pairs that raised chicks that year. Birds received both a maintenance and breeder diet, and for both we converted food consumption to energy intake (Joules/g body mass) using the combined fall weights of female and male. We compared daily energy intake with 6 meteorological variables (involving temperature, wind speed and humidity), photoperiod (natural and artificial) and egg laying …

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Resolutions Passed By The North American Crane Working Group, Tenth North American Crane Workshop Zacatecas City, Zacatecas, Mexico, North American Crane Working Group Jan 2008

Resolutions Passed By The North American Crane Working Group, Tenth North American Crane Workshop Zacatecas City, Zacatecas, Mexico, North American Crane Working Group

Proceedings of the North American Crane Workshop

Florida Crane habitat resolution
Florida has the largest population of non-migratory sandhill cranes in the world and winters a significant portion of the eastern population of greater sandhill cranes. And in Florida, efforts are underway to introduce migratory and non-migratory whooping cranes. In order to successfully establish and sustain these populations, appropriate habitat needs to be available. About 40% of Florida’s best crane habitat has been lost between 1973 and 2003, and the amount has increased since then. Because of this, these valuable populations of cranes are finding it more difficult to locate suitable habitat. We the NACWG by this …

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Earthworms And Acos: Determining A Preference For Cover Board Designs In Temperate Forests, Marie F. Schneider, Harry M. Tiebout Iii Jan 2008

Earthworms And Acos: Determining A Preference For Cover Board Designs In Temperate Forests, Marie F. Schneider, Harry M. Tiebout Iii

Biology Student Work

No abstract provided.

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Low-Density Rodent Communities In Eastern Virginia, Robert K. Rose, Jean F. Stankavich Jan 2008

Low-Density Rodent Communities In Eastern Virginia, Robert K. Rose, Jean F. Stankavich

Virginia Journal of Science

Two communities of small mammals were live trapped every other week for 15 months in linear oilfield habitat bordered by forested swampland in eastern Virginia. All nine species of the rodent community were present, mostly in low numbers and often intermittently. All species were characterized by high transiency, with a minority of marked animals becoming resident. Despite high trappability, all but two species in these communities had extremely low densities, suggesting that most species could not sustain populations via in situ reproduction.

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Geographic Distribution: Sphaerodactylus Elegans Elegans (Ashy Gecko). Usa: Florida: Broward Co., Louis A. Somma, Kenneth L. Krysko Jan 2008

Geographic Distribution: Sphaerodactylus Elegans Elegans (Ashy Gecko). Usa: Florida: Broward Co., Louis A. Somma, Kenneth L. Krysko

Papers in Herpetology

FLORIDA: BROWARD County: Pembroke Pines: 1031 NW 93rd Ave (26.0168833°N, 80.2695694°W; WGS84; elev. <1 >m). October 27, 2007. Collected by Lisa A. Charlton. Verified by F. Wayne King, Florida Museum of Natural History, University of Florida. One neonate captured in Jackson sticky trap set to sample insects in an alee tree (Blighia sapida). UF 152418. New county record. Originally turned in to Division of Plant Industry (DPI), Florida Department of Agriculture and Consumer Services, Gainesville, Florida, on October 31, 2007; Entomology Log No. 8204. This nonindigenous gecko was flrst reported from Key West, Monroe County, Florida, more than 85 …

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Waterhole Dynamics And Chemical Signals Of African Elephants ( Loxodonta Africana ), Stacie Marie Castelda Jan 2008

Waterhole Dynamics And Chemical Signals Of African Elephants ( Loxodonta Africana ), Stacie Marie Castelda

College of Graduate Studies: Theses & Dissertations

The distribution of mammals in a savanna environment is influenced by abiotic and biotic factors. The African savanna experiences distinct wet and dry seasons. Species become spatially restricted around water resources during the dry season, resulting in increased intraspecies and interspecies resource-based aggregation. A dominate species, such as the African elephant (Loxodonta africana), may influence this aggregation. I examined the influence of wet and dry seasons and ambient temperature on the use of a waterhole by elephants as well as the co-occurrence of elephants and other mammals at the waterhole. Biodiversity scans (October 2004-June 2007) and were performed at a …

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Project Limulus: What Long-Term Mark/Recapture Studies Reveal About Horseshow Crab Population Dynamics In Long Island Sound, Mark Beekey, Jennifer Mattei Jan 2008

Project Limulus: What Long-Term Mark/Recapture Studies Reveal About Horseshow Crab Population Dynamics In Long Island Sound, Mark Beekey, Jennifer Mattei

Biology Faculty Publications

Project Limulus is a long-term study of the population dynamics of the horseshoe crab population in Long Island Sound (LIS). We have tagged over 20,000 spawning adults from >20 beaches ranging from Greenwich to Stonington, CT since 1997. Cumulative recapture rates have reached 9%. On average 90% of the crabs are recaptured within a few miles of their original tag site within the first season. Between seasons, on average, 45% of crabs are recaptured within the same locality of where they were tagged. Of all recaptures, 99% of recaptured individuals are found within LIS. This past year we expanded the …

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Population Ecology Of The Golden Mouse, Robert K. Rose Jan 2008

Population Ecology Of The Golden Mouse, Robert K. Rose

Biological Sciences Faculty Publications

An understanding of the population dynamics of a species requires knowledge of the major life-history parameters of a population, including age at maturity, distribution of age classes, and lifetime reproductive contribution of the sexes, sex ratio, length of the breeding season, mean litter size, rates of growth and survival, and life span. Because few long-term studies have been conducted with Ochrotomys nuttalli as the focal species of investigation, only fragmentary information is available for many population parameters. As importantly, densities of golden mice often are low, making them difficult to evaluate statistically. Little has been published on age at maturity …

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