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Articles 1081 - 1110 of 5828

Full-Text Articles in Ecology and Evolutionary Biology

The Impact Of Marking On Cranes: An Issue Paper, Anne E. Lacy, Barry K. Hartup, David A. Brandt Jan 2022

The Impact Of Marking On Cranes: An Issue Paper, Anne E. Lacy, Barry K. Hartup, David A. Brandt

Proceedings of the North American Crane Workshop

As crane researchers and conservationists, our overarching objective is to learn and gather information about our study subjects while doing as little harm as possible. New technologies may be emerging too rapidly for researchers to assess the effectiveness or potential adverse effects of the devices, despite the ease and increasing accuracy of the information they provide. Researchers need to be able to gather information to answer various questions in a way that balances ethics and expense. With marking of cranes as a focal point, we discuss issues surrounding crane research based on various techniques, some health issues that are a …

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Ecological Risk Assessment For The Western Rock Lobster Resource : Workshop Procedure And Outcomes, R Stoklosa Jan 2022

Ecological Risk Assessment For The Western Rock Lobster Resource : Workshop Procedure And Outcomes, R Stoklosa

Fisheries Occasional Publications

No abstract provided.

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Black Fly Survey Of A Whooping Crane Reintroduction Area In Eastern Wisconsin, Richard P. Urbanek, Peter H. Adler Jan 2022

Black Fly Survey Of A Whooping Crane Reintroduction Area In Eastern Wisconsin, Richard P. Urbanek, Peter H. Adler

Proceedings of the North American Crane Workshop

Nest desertion due to harassment by black flies (Simulium annulus and S. johannseni) during incubation has been a major factor inhibiting success of the reintroduced Eastern Migratory Population of whooping cranes (Grus americana). To avoid this problem, which was prevalent in the core reintroduction area in central Wisconsin, the Whooping Crane Eastern Partnership changed the primary reintroduction area to eastern Wisconsin in 2011. However, a 2010 assessment of black flies in that area had concentrated predominantly on the southern portion of the new area. In 2017-2018, we collected the first samples of black flies in …

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Effects Of Release Techniques On Parent-Reared Whooping Cranes In The Eastern Migratory Population, Hillary L. Thompson, M. Susanna Glass, Marianne M. Wellington, Kim H. Boardman, Glenn H. Olsen Jan 2022

Effects Of Release Techniques On Parent-Reared Whooping Cranes In The Eastern Migratory Population, Hillary L. Thompson, M. Susanna Glass, Marianne M. Wellington, Kim H. Boardman, Glenn H. Olsen

Proceedings of the North American Crane Workshop

Reintroduction of an Eastern Migratory Population (EMP) of whooping cranes (Grus americana) in the United States by release of captive-reared individuals began in 2001. As of 2020, the EMP has approximately 21 breeding pairs and has had limited recruitment of wild-hatched individuals, thus captive-reared juveniles continue to be released into breeding areas in Wisconsin to maintain the population. We investigated the effects of release techniques on survival, behavior, site fidelity, and conspecific associations of 42 captive-parent-reared whooping cranes released during 2013-2019 into the EMP. Individuals were monitored intensively post-release, then as a part of a long-term monitoring program, …

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Vigilance Of Nesting Whooping Cranes In Juneau County, Wisconsin, Nicole M. Gordon, Darby P. Bolt, Hillary L. Thompson Jan 2022

Vigilance Of Nesting Whooping Cranes In Juneau County, Wisconsin, Nicole M. Gordon, Darby P. Bolt, Hillary L. Thompson

Proceedings of the North American Crane Workshop

Vigilance plays an important role in the detection of possible threats and reducing the risk of predation, including during the incubation period. We examined the visual vigilance of incubating whooping cranes (Grus americana) in Juneau County, Wisconsin, during the 2019 nesting season. We deployed 9 trail cameras and tagged crane presence and behavior in 32,801 photos which were used in our analysis. We assessed individual nest and environmental variables and their effects on vigilant behavior of incubating cranes using linear mixed-models. Vigilant behavior was defined by a posture in which the crane’s head was up, neck was erect, …

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Whooping Crane Stay Length In Relation To Stopover Site Characteristics, Andrew J. Caven, Aaron T. Pearse, David A. Brandt, Mary J. Harner, Greg D. Wright, David M. Baasch, Emma M. Brinley Buckley, Kristine L. Metzger, Matthew R. Rabbe, Anne E. Lacy Jan 2022

Whooping Crane Stay Length In Relation To Stopover Site Characteristics, Andrew J. Caven, Aaron T. Pearse, David A. Brandt, Mary J. Harner, Greg D. Wright, David M. Baasch, Emma M. Brinley Buckley, Kristine L. Metzger, Matthew R. Rabbe, Anne E. Lacy

Proceedings of the North American Crane Workshop

Whooping crane (Grus americana) migratory stopovers can vary in length from hours to more than a month. Stopover sites provide food resources and safety essential for the completion of migration. Factors such as weather, climate, demographics of migrating groups, and physiological condition of migrants influence migratory movements of cranes (Gruidae) to varying degrees. However, little research has examined the relationship between habitat characteristics and stopover stay length in cranes. Site quality may relate to stay length with longer stays that allow individuals to improve body condition, or with shorter stays because of increased foraging efficiency. We examined this …

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Mortality Risk Associated With Urban Land Use For Adult Eastern Diamondback Rattlesnakes (Crotalus Adamanteus), Mya Wiles Jan 2022

Mortality Risk Associated With Urban Land Use For Adult Eastern Diamondback Rattlesnakes (Crotalus Adamanteus), Mya Wiles

Theses, Dissertations and Capstones

Snakes have been a traditionally under-represented organism in urban ecology, but they face similar, if not greater challenges in the face of growing urban sprawl. Eastern diamondback rattlesnakes (Crotalus adamanteus, EDBs) are under consideration for listing under the Endangered Species Act due to population declines resulting from historical human persecution and habitat loss. This study used radio-telemetry data from a long-term monitoring project of adult EDBs on a developed sea island in South Carolina, USA. I reclassified a National Land Cover Dataset to reflect relative mortality risk for snakes attempting to move through the landscape. High-risk cover types …

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Spatial And Temporal Variability Of Mercury In Upper And Lower Red Lake Walleye, Tyler Orgon Jan 2022

Spatial And Temporal Variability Of Mercury In Upper And Lower Red Lake Walleye, Tyler Orgon

Biology Graduate Theses

Mercury is a global pollutant that is released into our environment by natural and anthropogenic processes resulting in extensive studies conducted on mercury cycling in aquatic ecosystems which has led to the issuance of human-health-based fish-consumption advisories. We examined total mercury concentrations in Walleye Sander vitreus from Upper and Lower Red Lakes, located in north central Minnesota, between 2019 and 2020. Upper and Lower Red Lake form a contiguous water body consisting of two large (483.1 and 665.6 km2, respectively) basins that are naturally connected by a 1.4 km-wide strait. Both basins are important fisheries for recreation, subsistence, and commercial …

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Stomach Contents And Stable Isotope Analysis Reveal Ontogenetic Shifts And Spatial Variability In Brama Australis Diet, Sebastian A. Klarian, Eric T. Schultz, María Francisca Hernández, Juan Antonio Valdes, Francisco Fernandoy, Mónica Barros, Sergio Neira, Hugo Arancibia Jan 2022

Stomach Contents And Stable Isotope Analysis Reveal Ontogenetic Shifts And Spatial Variability In Brama Australis Diet, Sebastian A. Klarian, Eric T. Schultz, María Francisca Hernández, Juan Antonio Valdes, Francisco Fernandoy, Mónica Barros, Sergio Neira, Hugo Arancibia

EEB Articles

Many marine fisheries rely on production and energy flow in the pelagic zone, thus sustainable management of exploited pelagic fishes benefits from insight into temporal, spatial and ontogenetic variability in the trophic ecology of these species. Here we analyze stomach contents and stable isotopes to reveal spatial variability (focusing on two fishing grounds, north and south of an oceanographic barrier in the Pacific Ocean) and ontogenetic changes (contrasting immature and mature) in Southern Ray’s Bream (Brama australis) diet composition in Chilean waters. Stomach contents analysis indicated that euphausiids were predominant components of the diet in both fishing grounds and ontogenetic …

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Seasonal Reproductive Allocation In Landlocked Alewife Alosa Pseudoharengus, In The Context Of Niche Construction And Eco-Evolutionary Feedbacks, Foivos Mouchlianitis, Eric T. Schultz, Kostas Ganias Jan 2022

Seasonal Reproductive Allocation In Landlocked Alewife Alosa Pseudoharengus, In The Context Of Niche Construction And Eco-Evolutionary Feedbacks, Foivos Mouchlianitis, Eric T. Schultz, Kostas Ganias

EEB Articles

The bidirectional dynamics between species and their biotic and abiotic environments, known as eco-evolutionary feedbacks, may shift the direction of evolution and alter the ecological role of species. Alewife, Alosa pseudoharengus, is an exemplary species to study reciprocal feedbacks between ecology and evolution, owing to repeated independent derivations of a landlocked life history from an ancestral anadromous form. In this study we analysed the reproductive allocation during the spawning season in a landlocked Alewife population in the context of eco-evolutionary feedbacks. We also compared our findings with previous results from a neighbouring anadromous population of the species. Similarities were found …

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Factors Affecting The Sex Ratio Of White-Tailed Deer (Odocoileus Virginianus) Fetuses In Arkansas, Jorista Garrie, Ralph Meeker Jan 2022

Factors Affecting The Sex Ratio Of White-Tailed Deer (Odocoileus Virginianus) Fetuses In Arkansas, Jorista Garrie, Ralph Meeker

Journal of the Arkansas Academy of Science

Health of the mother is known to affect the sex-ratio of the offspring in sexually dimorphic mammals. Both density-dependent and environmental factors (conditions at present, or seasonal conditions the year before) could impact the health of the mother. There are however two opposing hypotheses for whether a mother in good health should invest more in a strong son (that can father many offspring) or in a daughter (that can stay in the same area and use good resources). Fetuses from 1,208 female white-tailed deer (Odocoileus virginianus) were collected over a 10-year period (2002-2012), across 75 counties in Arkansas. …

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Sentience In Decapods: Difficulties To Surmount, Michael L. Woodruff Jan 2022

Sentience In Decapods: Difficulties To Surmount, Michael L. Woodruff

Animal Sentience

In the target article Crump et al. present 8 criteria to assess whether decapods experience pain. Four of these -- sensory integration, motivational trade-offs, flexible self-protection, and associative learning -- could be used to assess sentience in general. In this commentary I discuss difficulties with using these criteria to provide evidence of sentience in decapods, particularly if this evidence is to change public opinion and policies. These difficulties are lack of evidence, the potential to eventually explain the neurobiological basis of the behaviors chosen as criteria, thereby eliminating any explanatory work for sentience, and the reluctance to bring animals that …

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Sentience As Part Of Emotional Lives, Frans B. M. De Waal Jan 2022

Sentience As Part Of Emotional Lives, Frans B. M. De Waal

Animal Sentience

It is high time to explore the sentience of invertebrate animals, but this topic cannot be discussed without also exploring their emotional lives, including positive emotions. Sentience probably evolved to allow the regulation of emotions by endowing them with feelings.

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Decapods As Food, Companions And Research Animals: Legal Impact Of Ascribing Sentience, Jonathan J. Cooper, Ambrose Tinarwo, Beth A. Ventura Jan 2022

Decapods As Food, Companions And Research Animals: Legal Impact Of Ascribing Sentience, Jonathan J. Cooper, Ambrose Tinarwo, Beth A. Ventura

Animal Sentience

This commentary provides an overview of the practical implications of attributing sentience to protect decapods as food, companion and research animals in the UK context. Recognising their capacity to suffer has implications for humane slaughter in farming and fishing sectors. It should also place a greater duty of care on owners of captive decapods, considering their needs and avoiding unnecessary suffering. The recognition of decapod sentience should also have an impact on their protection as research animals, although research with a potential to cause suffering may be needed to better understand decapods’ capacity to suffer.

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Pros And Cons Of A Framework For Evaluating Potential Pain In Decapods, Robert W. Elwood Jan 2022

Pros And Cons Of A Framework For Evaluating Potential Pain In Decapods, Robert W. Elwood

Animal Sentience

The rigorous framework for research into potential pain in decapods was successful in allowing legislators in the United Kingdom to evaluate a complex scientific issue. However, it might produce problems for research. I discuss doubts about the usefulness of the eight criteria. Some have yet to receive any investigation and others do not allow much inference about pain. In addition, some existing studies are not covered in the framework. Most worrying, however, is the potential for stifling future research of novel areas that are excluded from the framework.

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Why The Recognition Of Sentience Is So Important For Animal Welfare, Mark Jones Jan 2022

Why The Recognition Of Sentience Is So Important For Animal Welfare, Mark Jones

Animal Sentience

Rowan et al. (2022) provide a useful summary of the history and development of the philosophical, public, and legal recognition of animal sentience and its importance in improving the welfare of animals. Here I argue for the incorporation of the precautionary principle in sentience recognition, and the wider significance of sentience recognition to the current climate, biodiversity and human health crises.

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Maternal Drivers Of Reproductive Output In The Lizard Family Scincidae: A Phylogenetic Comparative Approach, William Zang Jan 2022

Maternal Drivers Of Reproductive Output In The Lizard Family Scincidae: A Phylogenetic Comparative Approach, William Zang

West Chester University Master’s Theses

Scincidae is one of the most diverse families of squamates, comprising over 1,300 species of lizards with a variety of life history and ecological traits. This diversity includes three reproductive modes, where some species reproduce via oviparity (egg-laying), viviparity (live birth) or use of a mixed strategy (females switch modes). In this study, it was sought whether reproductive output differs between scincid species using these reproductive modes. Reproductive output is defined as the average product of offspring abundance and size per reproductive event, representing the reproductive effort of an individual. Additionally, the importance of phylogeny (evolutionary relatedness) and a suite …

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Analysis Of Hematocrit Levels In Walleye Sander Vitreus From Similar Waterbodies, Alyssa Hauser Jan 2022

Analysis Of Hematocrit Levels In Walleye Sander Vitreus From Similar Waterbodies, Alyssa Hauser

Journal of Earth and Life Science

Walleye Sander vitreus are a popular fish among anglers and hold a prominent place in Minnesotan’s identity as their state fish. Because of this, multiple management practices are used to ensure the continued health of their populations within Minnesota waters. In this study, the process of analyzing hematocrit levels was used to determine if the analysis of hematological parameters could be a useful tool in detecting differences in population health. To evaluate this, blood samples were acquired from age-0 and age-1 fish from two similar lakes and run through a hematocrit centrifuge to separate platelets from plasma to read the …

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The Effects Of Diet On Yellow Perch Morphology Throughout Lake Bemidji, Quiana L. Radaich Jan 2022

The Effects Of Diet On Yellow Perch Morphology Throughout Lake Bemidji, Quiana L. Radaich

Journal of Earth and Life Science

Morphology is very important as it looks at the arrangement of an organism’s parts to determine their functionality, development, and how they could have changed through evolution. It is also important for the identification of species as it can show how closely species are related. This study examines if the morphology of yellow perch changes throughout Lake Bemidji. Along with examining a subset of five stomachs for each group (A-F) of yellow perch collected to determine if diet was a driving force behind morphological changes. The data collected in this study suggested that morphology does change throughout Lake Bemidji and …

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Final Report Floating Upwelling System Harvest Road Oceans, Robert Michael, Scott Bennett Jan 2022

Final Report Floating Upwelling System Harvest Road Oceans, Robert Michael, Scott Bennett

Fisheries Occasional Publications

A Floating Upwelling System or FLUPSY is a mechanical system for the culture of seed stock during the nursery stage of commercial bivalve production.

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Living In A Gradient: The Influence Of Water Temperature Variation On Development, Settling Time And Survival Of Pallid Sturgeon Larvae In The Missouri River, Maria Elizabeth Erceg Jan 2022

Living In A Gradient: The Influence Of Water Temperature Variation On Development, Settling Time And Survival Of Pallid Sturgeon Larvae In The Missouri River, Maria Elizabeth Erceg

Electronic Theses and Dissertations

Pallid Sturgeon (Scaphirhynchus albus) are a federally endangered species experiencing widespread reproduction and recruitment failures. Recruitment failure is hypothesized to be caused by habitat modifications made to the Missouri River that disrupt connectivity and alter temperature profiles downstream of constructed dams. Hypolimnetic releases from Missouri River dams affect the temperature downstream, creating colder conditions during the downstream drifting phase for dispersing larvae. Understanding the influence of water temperature changes on larval development is crucial for recovery efforts. In this study, we evaluated the effects of water temperature daily heating rate on energy use, settling behavior, and growth rate of endogenously …

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Spatio-Temporal Movement Patterns Of Sub-Adult Adfluvial Bull Trout, Aimee Taylor Jan 2022

Spatio-Temporal Movement Patterns Of Sub-Adult Adfluvial Bull Trout, Aimee Taylor

All Master's Theses

Bull Trout in the Yakima River basin of Washington are primarily adfluvial, often using managed lakes as habitat. Kachess Lake, composed of Big and Little Kachess Lakes, is managed by the Bureau of Reclamation (BOR) for water storage. BOR plans to build a structure that can withdraw an additional 200,000 acre-feet of water in drought years, which would disconnect the two basins for multiple years. This study examined the spatio-temporal movement of sub-adult Bull Trout in Kachess Lake to understand distribution patterns and the effects of environmental variables. We sought to answer 1) does time (week of the year), diel …

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Understanding Caribou Population Cycles, Jack R. St. John Jan 2022

Understanding Caribou Population Cycles, Jack R. St. John

Undergraduate Theses, Professional Papers, and Capstone Artifacts

The complex population dynamics of caribou (Rangifer tarandus) were studied to determine the patterns of their population cycles and the processes driving them. It is well established, via previous archaeological research and Indigenous knowledge, that large migrating caribou herds found in and around the tundra at northern latitudes experience population boom and busts roughly every several decades. However, the processes driving the dynamics of these cycles are relatively unknown, which makes managing caribou herds for recreational and subsistence harvests difficult. It has been hypothesized that a combination of intrinsic and extrinsic factors shape these cycles, with density-dependence, predation, …

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Spatiotemporal Relationships Of Coyotes And Free-Ranging Domestic Cats As Indicators Of Conflict In Culver City, California, Rebecca N. Davenport, Melinda Weaver, Katherine C. B. Weiss, Eric G. Strauss Jan 2022

Spatiotemporal Relationships Of Coyotes And Free-Ranging Domestic Cats As Indicators Of Conflict In Culver City, California, Rebecca N. Davenport, Melinda Weaver, Katherine C. B. Weiss, Eric G. Strauss

Center for Urban Resilience Scholarship

As habitat generalists, urban coyote (Canis latrans) populations often utilize an abundance of diverse food sources in cities. Within southern California, domestic cats (Felis catus) comprise a higher proportion of coyote diets than in other studied urban areas throughout the United States. However, it is unclear which ecological factors contribute to higher rates of cat depredation by coyotes in this region. While previous research suggests that coyote presence may have a negative effect on free-ranging domestic cat distributions, few studies have determined whether urban green spaces affect coyote or free-ranging domestic cat occurrence and activity within …

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Observations Of Whooping Crane Parental Provisioning Of Chicks, Glenn H. Olsen Jan 2022

Observations Of Whooping Crane Parental Provisioning Of Chicks, Glenn H. Olsen

Proceedings of the North American Crane Workshop

Crane chicks are dependent on parent birds for provisioning during the first few months of life, but no study has examined this provisioning in detail. In 2014 research staff at the U.S. Geological Survey, Eastern Ecological Science Center (formerly Patuxent Wildlife Research Center), in Laurel, Maryland, made multiple observations of parent whooping cranes (Grus americana) feeding or interacting with their chick during the 3 months from hatching to fledging. Both parents participated in the feeding of the chick and only 1 chick was raised by each pair of parent whooping cranes. Initially feeding frequency was low (0-20 times …

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Surveys And Population Estimates Of A Distinctive Subpopulation Of Sandhill Cranes In The Fraser River Lowlands Of British Columbia, Myles M. Lamont Jan 2022

Surveys And Population Estimates Of A Distinctive Subpopulation Of Sandhill Cranes In The Fraser River Lowlands Of British Columbia, Myles M. Lamont

Proceedings of the North American Crane Workshop

A poorly understood subpopulation of sandhill cranes (Grus canadensis) breeds at scattered locations in the lower Fraser River Valley on the south coast of British Columbia. The area also harbors the northernmost population of overwintering sandhill cranes anywhere in its range. While sporadic monitoring has been carried out since the mid-1960s, no formal survey efforts have been attempted for the entire Fraser River lowland subpopulation. During 2014-2019 we collected groundbased survey data on presence and occupation of territories within the study area; this effort was supported by citizen science contributions. On 20 June 2019, we flew a fixed-width, …

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Whooping Crane Nest Building In Southwest Indiana, Amy J. Kearns, Hillary L. Thompson, Allisyn-Marie T. Y. Gillet Jan 2022

Whooping Crane Nest Building In Southwest Indiana, Amy J. Kearns, Hillary L. Thompson, Allisyn-Marie T. Y. Gillet

Proceedings of the North American Crane Workshop

The first documented case of whooping crane (Grus americana) nest building in Indiana is described. During spring 2015, a pair of whooping cranes did not leave their wintering grounds in Gibson County, Indiana, to return to their summering area in Wisconsin. Three nest platforms were discovered after the death of the female crane. To date, this is the only documented example of a whooping crane pair in the reintroduced Eastern Migratory Population (EMP) building nest platforms outside of Wisconsin. Although fidelity to the core nesting areas in Wisconsin is strong, and natal dispersal is usually <30 km, this example from Indiana shows that whooping cranes in the EMP may have the potential to pioneer nesting areas far outside of core reintroduction areas.

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Summary Of Mortality Among Captive Cranes At The International Crane Foundation: 2000–2020, Barry K. Hartup, Robert Phillips Jan 2022

Summary Of Mortality Among Captive Cranes At The International Crane Foundation: 2000–2020, Barry K. Hartup, Robert Phillips

Proceedings of the North American Crane Workshop

We reviewed mortalities of captive cranes at the International Crane Foundation (ICF) between 2000 and 2020 to provide broad insights into contemporary factors affecting the collection’s health and survival. Sixty-three deaths were documented in 13 of 15 crane species held in the ICF collection. The mean annual mortality during the study was 2.6% and the mean age (±SD) at death was 28.4 (±12.7) years. The overall total number of deaths of males and females was similar, but there was an association between sex and death of adult versus geriatric (>25 years) cranes (P < 0.01); males were more likely to die at geriatric age than females. Deaths were commonly associated with chronic health and management problems (n = 44, 79%) versus …

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Florida Sandhill Crane Relocates Egg During Incubation, Timothy A. Dellinger, Miranda L. Watford, Ronald R. Bielefeld Jan 2022

Florida Sandhill Crane Relocates Egg During Incubation, Timothy A. Dellinger, Miranda L. Watford, Ronald R. Bielefeld

Proceedings of the North American Crane Workshop

Anecdotal accounts of birds moving their eggs to a new location have been reported in shorebirds, waterfowl, and woodpeckers. We report relocation of an egg, 2 days prior to hatching, by an adult Florida sandhill crane (Grus canadensis pratensis). We do not know why the egg was moved, but egg movement among other species appears to be associated with nest disturbance by humans, animals, or environmental conditions.

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Initial Evaluation Of Cyclic Adenosine Monophosphate Enzyme Immunoassay For Use With Crane Semen Samples, Megan E. Brown, Kim Boardman, Katie L. Edwards Jan 2022

Initial Evaluation Of Cyclic Adenosine Monophosphate Enzyme Immunoassay For Use With Crane Semen Samples, Megan E. Brown, Kim Boardman, Katie L. Edwards

Proceedings of the North American Crane Workshop

The management of ex situ and in situ populations of many wildlife species requires detailed knowledge of a species’ reproductive biology. For species such as cranes, where artificial insemination is a critical component of ex situ management strategies, understanding normal sperm function is especially important. Previous research has shown that captive cranes exhibit highly variable production and quality of semen samples produced by individual males and high levels of variation of cell concentration and motility across different species. Cyclic adenosine monophosphate (cyclic AMP) has been implicated in regulating sperm function, such as cell motility, and may affect an individual’s ability …

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