Population Biology Commons^™

Summary Of Sandhill Crane Hunting Seasons In Kansas 1993–2007, David E. Sharp, Helen M. Hands, James A. Dubovsky, John E. Cornely

Proceedings of the North American Crane Workshop

The mid-continent population of sandhill cranes (Grus canadensis) is the largest population of cranes in North America. Hunting seasons for sandhill cranes were closed in 1916 and gradually resumed in Mexico (1940), the United States (1961), and Canada (1964). As knowledge of the biology of cranes and experience with hunting seasons increased, areas in which hunting was permitted expanded, and by 1992 all but 2 states (Nebraska and Kansas) in the U.S. portion of the Central Flyway conducted sport hunting seasons for this population. In 1993 Kansas resumed hunting and initial seasons were limited to specified geographic areas of …

Proceedings Of The Eleventh North American Crane Workshop: Preface And Contents

Proceedings of the North American Crane Workshop

The North American Crane Working Group (NACWG) is an organization of professional biologists, aviculturists, land managers, and other interested individuals dedicated to the conservation of cranes and their habitats in North America. Our group meets approximately every 3 years to exchange new information on research and conservation of sandhill and whooping cranes and occasionally reports from abroad. Our meeting in Wisconsin Dells, Wisconsin, 23-27 September 2008, was no exception. The workshop was ably organized by Tom Hoffman, the scientific program was well-constructed by Jane Austin, and George Archibald and Richard Urbanek helped to bring together a memorable field day in …

Wintering Sandhill Crane Distribution And Habitat Use Patterns At Bosque Del Apache National Wildlife Refuge, New Mexico, Tandi L. Perkins, Leigh H. Fredrickson

Proceedings of the North American Crane Workshop

The single most important factor regulating sandhill crane (Grus canadensis) populations is their ability to carry out annual life cycle events while responding to changing habitat availability and distribution across local, regional, and continental landscapes. Wetland and cropland resource availability and distribution across the landscape have become increasingly unpredictable. Recent changes in farming practices, urbanization, and prevailing drought conditions in New Mexico have transformed and reduced dynamic, heterogeneous landscapes into scattered fragments of the original setting. Concerns are increasing for the cumulative influence of these often irreversible actions in providing the type of resources needed by cranes at …

Promiscuous Mating In Feral Pigs (Sus Scrofa) From Texas, Usa, Johanna Delgado-Acevedo, Angeline Zamorano, Randy W. Deyoung, Tyler A. Campbell, David G. Hewitt, David B. Long

United States Department of Agriculture Wildlife Services: Staff Publications

Context. Feral pigs represent a significant threat to agriculture and ecosystems and are disease reservoirs for pathogens affecting humans, livestock and other wildlife. Information on the behavioural ecology of feral pigs might increase the efficiency and effectiveness of management strategies.

Aims. We assessed the frequency of promiscuous mating in relation to oestrous synchrony in feral pigs from southern Texas, USA, an agroecosystem with a widespread and well established population of feral pigs. An association between multiple paternity of single litters and synchrony of oestrous may indicate alternative mating strategies, such as mateguarding.

Methods. We collected gravid sows at …

Leptodactylus Savagei, W. R. Heyer, Miriam M. Heyer, Rafael O. De Sá

Biology Faculty Publications

Adult Leptodactylus savagei are large, the head is as wide as long or usually wider than long, and the hind limbs are moderate in length (Table 1; Heyer and Thompson (2000) provided definitions of adult size and leg length categories for Leptodactylus). Male vocal sacs are not visible externally. Sexually active males have hypertrophied forearms, usually 1 large black spine on each thumb, rarely with 1 large spine and a prepollical bump, and a pair of black chest spines. A pair of entire dorsolateral folds extend anteriorly from at least one_half to full distance from eye to groin, the …

Seasonal Variability In Ichthyoplankton Abundance And Assemblage Composition In The Northern Gulf Of Mexico Off Alabama, Frank J. Hernandez, Jr, Sean P. Powers, William M. Graham

University Faculty and Staff Publications

Multiyear ichthyoplankton surveys used to monitor larval fish seasonality, abundance, and assemblage structure can provide early indicators of regional ecosystem changes. Numerous ichthyoplankton surveys have been conducted in the northern Gulf of Mexico, but few have had high levels of temporal resolution and sample replication. In this study, ichthyoplankton samples were collected monthly (October 2004–October 2006) at a single station off the coast of Alabama as part of a long-term biological survey. Four seasonal periods were identified from observed and historic water temperatures, including a relatively long (June–October) “summer” period (water temperature >26°C). Fish egg abundance, total larval abundance, and …

The Ratio Of Gametophytes To Tetrasporophytes Of Intertidal Chondrus Crispus (Gigartinaceae) Across A Salinity Gradient, Michele Guidone, Sean Grace

Biology Faculty Publications

Population studies of the Gigartinaceae (Rhodophyta) have often observed that the ratio of gametophytes to tetrasporophytes varies with the location of the population or the time of sampling. For some species, patterns have emerged that correlate this ratio to one or a few particular environmental variables, such as elevation, wave exposure, or season. Identifying these distributional patterns is an important step towards understanding what (if any) ecological differences exist between the two free-living life history stages.

The purpose of this study was to measure the ratio of gametophytes to tetrasporophytes of intertidal populations of Chondrus crispus across a decreasing salinity …

Reproductive Behavior In Horseshoe Crabs: Does Density Matter?, Jennifer Mattei, Mark Beekey, Adam Rudman, Alyssa Woronik

Biology Faculty Publications

While the four species of horseshoe crabs share many common reproductive traits with respect to their reproductive systems, they do differ with respect to their mating behavior (monogamy vs. polygynandry). Past research has attributed these differences to a number of factors including: spawning densities, operational sex ratios (OSR’s), male condition (or age), environmental and/or genetic factors, or a combination thereof. Mating behaviors in the three Asian horseshoe crab species (Tachypleus gigas , T. tridentatus, and Carcinoscorpius rotundicauda ) with low spawning densities and 1:1 operational sex ratios are typically monogamous. In Limulus polyphemus , mating behavior is more …

Movement Patterns And Population Genetics Of The American Horseshoe Crab In Relation To Long Island Sound Conservation Strategies, Jo-Marie Kasinak, Kirk A. Bartholomew, Mark Beekey, Jennifer Mattei

Biology Faculty Publications

The Connecticut Department of Environmental Protection (CTDEP) established three no-harvest zones for the horseshoe crab (Limulus polyphemus) population as part of a conservation plan for the species. Data from a long-term mark/recapture study of horseshoe crabs in conjunction with a microsatellite-based genetic survey of the population were analyzed to determine if this plan was appropriate to conserve genetic diversity and broaden our knowledge of movement patterns of Limulus in Long Island Sound (LIS). To date, ~53,000 crabs have been tagged over a 10 year period through the Project Limulus program with an annual average recapture rate of 12 …