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Full-Text Articles in Population Biology

Black Bear, Jimmy D. Taylor, James P. Phillips Jan 2020

Black Bear, Jimmy D. Taylor, James P. Phillips

Wildlife Damage Management Technical Series

The American black bear (Ursus americanus, Figure 1) is a challenging species for wildlife agencies to manage due to its size, intelligence, extensive range, food habits, and adaptability, as well as societal views. In North America alone, agencies receive more than 40,000 complaints about black bear annually. Black bears are known as ‘food-driven’ animals, meaning most conflicts result from a bear’s drive to meet its nutritional needs. Not surprisingly, an overwhelming proportion of conflicts are related to their use of anthropogenic (human) food sources, such as garbage, bird food, and crops. Understanding what drives human-bear conflict is the first part …


Freshwater Pond Use By Whooping Cranes During A Wet Winter In Coastal Texas, Raymond D. Kirkwood, Elizabeth H. Smith Jan 2018

Freshwater Pond Use By Whooping Cranes During A Wet Winter In Coastal Texas, Raymond D. Kirkwood, Elizabeth H. Smith

Proceedings of the North American Crane Workshop

Wintering whooping cranes (Grus americana) in the Aransas-Wood Buffalo Population have a restricted range along coastal Texas, and they rely on coastal salt marshes and tidal ponds for feeding and roosting habitat as well as upland freshwater ponds for dietary drinking water during drought periods. These upland ponds were used extensively by wintering whooping cranes during a multi-year drought (2011-2014), and use terminated when frequent localized rainfall events occurred across the wintering range. Despite optimum bay salinities that occurred during this study (February-March 2016) in a 6-week winter period, whooping cranes continued to use at least 1 of …


Geese, Ducks And Coots, John L. Cummings Aug 2016

Geese, Ducks And Coots, John L. Cummings

Wildlife Damage Management Technical Series

Canada geese, snow geese, ducks, and American coots all have been implicated in agricultural crop and turf damage. Canada geese and snow geese that graze on winter wheat and rye crops can reduce subsequent grain and vegetative yields. Canada geese also cause serious damage to sprouting soybeans in spring and to standing cornfields in the autumn. The most common damage to agricultural resources associated with geese results from consumption of crops. Other impacts involve unacceptable accumulations of feces in pastures, trampling of emerging crops, and increased erosion and runoff from fields where the cover crop has been grazed. Canada geese …


Use Of Freshwater Ponds By Whooping Cranes During A Drought Period, Karis Ritenour, Elizabeth Smith, Barry K. Hartup Jan 2016

Use Of Freshwater Ponds By Whooping Cranes During A Drought Period, Karis Ritenour, Elizabeth Smith, Barry K. Hartup

Proceedings of the North American Crane Workshop

Whooping cranes (Grus americana) spend nearly half their annual cycle in coastal habitats within and around the Aransas National Wildlife Refuge Complex (ANWRC) located in the central portion of the Texas Coast. When drought conditions prevail in their winter range and salinities in the local bays exceed 23 parts per thousand (ppt), whooping cranes must seek alternate sources of dietary drinking water (Stehn 2008, Chavez- Ramirez and Wehtje 2012). They begin frequent (often daily) trips to freshwater sources in upland areas. These trips may result in extra energy expenditures that can impact their overall health and ability to …


Sandhill Crane Staging And Whooping Crane Migratory Stopover Dynamics In Response To River Management Activities On The Central Platte River, Nebraska, Usa, Felipe Chavez-Ramirez Jan 2010

Sandhill Crane Staging And Whooping Crane Migratory Stopover Dynamics In Response To River Management Activities On The Central Platte River, Nebraska, Usa, Felipe Chavez-Ramirez

Proceedings of the North American Crane Workshop

The Central Platte River Valley (CPRV) is a critical stopover for migrating whooping cranes (Grus americana) and the most important staging area for sandhill cranes (G. canadensis) in North America. Due to reduced water flows caused by human activities, the Platte River no longer follows its traditional hydrograph which consisted of high spring flows that produced scouring action that eliminated vegetation. To provide adequate crane roosting habitat during stopover and staging periods, annual and woody vegetation has been mechanically cleared on eastern portions of the CPRV since 1980. Staging sandhill crane riverine roosting area has decreased …


Population Status , Hunting Regulations , And Harvests Of The Rocky Mountain Population Of Greater Sandhill Cranes, 1981–2005, Kammie L. Kruse, David E. Sharp, James A. Dubovsky Jan 2008

Population Status , Hunting Regulations , And Harvests Of The Rocky Mountain Population Of Greater Sandhill Cranes, 1981–2005, Kammie L. Kruse, David E. Sharp, James A. Dubovsky

Proceedings of the North American Crane Workshop

The Rocky Mountain Population (RMP) of greater sandhill cranes (Grus canadensis tabida) was not hunted in the U.S. from 1916 until 1981, when Arizona initiated the first modern-day season. Hunting programs in the U.S. were subsequently expanded to 6 states for the RMP and have been guided by a cooperative flyway management plan, including a harvest strategy, which has been periodically updated and endorsed by the Central and Pacific Flyway Councils. From a management perspective, 3 population parameters have been identified to monitor the status and health of this population: harvest, recruitment, and population size. The number of …


Greater Sandhill Crane: Research And Management In California Since 1978, Ronald W. Schlorff Jan 2005

Greater Sandhill Crane: Research And Management In California Since 1978, Ronald W. Schlorff

Proceedings of the North American Crane Workshop

The greater sandhill crane (Grus canadensis tabida) was added to the California list of threatened species in 1983, and the subspecies has been the subject of research and management actions instituted by the California Department of Fish and Game (hereafter Department). Since 1978, the Department has conducted research and recovery actions including periodic breeding ground and wintering area studies, population monitoring, participated in developing Pacific Flyway crane management plans, acquisition and management of key habitats on breeding and wintering grounds, and developed a draft greater sandhill crane recovery strategy. These tasks were accomplished with the assistance of crane …


Beaver Research In The Uvs Nuur Region, Michael Stubbe, N. Dawaa, R. Samjaa, Annegret Stubbe, A. P. Saveljev, D. Heidecke, D. Sumjaa, H. Ansorge, S. Shar, J.-F. Ducroz Jan 2005

Beaver Research In The Uvs Nuur Region, Michael Stubbe, N. Dawaa, R. Samjaa, Annegret Stubbe, A. P. Saveljev, D. Heidecke, D. Sumjaa, H. Ansorge, S. Shar, J.-F. Ducroz

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

In 1985, 1988, and 2002 Castor fiber birulai was introduced to the Tes Gol of the Uvs Nuur basin in North-western Mongolia. The beavers migrated through the Republic of Tyva and settled in the middle part of Tes Gol near the Tyvinian-Mongolian border. About 10 colonies were recorded in this region in 2002. Strict protection of Castor fiber birulai has to be ensured in Mongolia and the Republic of Tyva in future.


Der Einsatz Der Luzerne-Blattschneiderbiene, Megachile Rotundata (Hymenoptera: Megachilidae), Zur Bestäubung Von Luzerne In Der Mongolei = Management Of The Alfalfa Leaf-Cutter Bee, Megachile Rotundata (Hymenoptera: Megachilidae), For Alfalfa Pollination In Mongolia, Karsten Seidelmann, Čojrog Batchujag, Manfred Dorn Jan 2005

Der Einsatz Der Luzerne-Blattschneiderbiene, Megachile Rotundata (Hymenoptera: Megachilidae), Zur Bestäubung Von Luzerne In Der Mongolei = Management Of The Alfalfa Leaf-Cutter Bee, Megachile Rotundata (Hymenoptera: Megachilidae), For Alfalfa Pollination In Mongolia, Karsten Seidelmann, Čojrog Batchujag, Manfred Dorn

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

The propagation of the alfalfa leaf-cutter bee, Megachile rotundata was tested from 1988 to 1991 on alfalfa seed growing fields at the Uvs-Nuur Basin in the North-West of Mongolia. We used the loose-cell technology in combination with wooden grooved boards (dimensions of the nesting holes: 8 × 110 mm). The climatic conditions at the investigation area proved to be favorable for the rearing of the bees. The average temperature was above 21 °C during 8.5 h by a mean sunshine duration of 6.4 h and sporadic rainfall. Nevertheless, the night temperatures felled below 10 °C and are responsible for a …


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 Jan 2005

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 …


Increased Egg Conservation-Is It Essential For Recovery Of Whooping Cranes In The Aransasiwood Buffalo Population?, James C. Lewis Jan 2001

Increased Egg Conservation-Is It Essential For Recovery Of Whooping Cranes In The Aransasiwood Buffalo Population?, James C. Lewis

Proceedings of the North American Crane Workshop

The whooping crane (Grus americana) is in a race for survival against adversities (genetic, demographic, and environmental) that are only partially understood. There is increasing evidence of genetic problems (drift, inbreeding, and loss of heterozygosity) in the captive population that likely also exist in the wild Aransas-Wood Buffalo Population (A WP), a consequence of the 1940s population bottleneck. Small populations are vulnerable to extinction through catastrophic events and random changes in productivity or survival. Negative environmental effects faced by whooping cranes include upstream diversion which diminish freshwater (nutrient) inflow into Texas wintering habitats, and expanding human activities along …


Whooping Crane Egg Management: Options And Consequences, David H. Ellis, George F. Gee Jan 2001

Whooping Crane Egg Management: Options And Consequences, David H. Ellis, George F. Gee

Proceedings of the North American Crane Workshop

Eggs to build captive whooping crane (Grus americana) flocks and most eggs for reintroduction experiments have come from second viable eggs in 2-egg clutches in Canada. Four years ago, egg removal ceased. Based on reproductive rates for years when second eggs were removed and for years when eggs were not removed, we project numbers of young fledging in the wild and in captivity for the 2 most likely egg-management strategies. From existing data sets, we find that reproductive performance was, on average, better during the era of routine removal of the second viable eggs than when no manipulation …


Population Status, Hunting Regulations, Hunting Activity, And Harvests Of Mid-Continent Sandhill Cranes, David E. Sharp, William D. Vogel Jan 1992

Population Status, Hunting Regulations, Hunting Activity, And Harvests Of Mid-Continent Sandhill Cranes, David E. Sharp, William D. Vogel

Proceedings of the North American Crane Workshop

The mid·continent population of sandhill cranes (Grus canadensis) was protected from 1916 until 1961, when hunting resumed on a limited basis. Areas open to hunting were experimentally expanded during 1961-72, but during the subsequent 1975-90 period only minor changes were made in the 8 Central Flyway states that established hunting seasons. Annual spring surveys conducted during 1982-90 indicated the population was stable at objective levels, with spring populations estimated at about 540,000 and fall flights near 590,000. Special federal hunting permits have been required for all bunters participating in regular seasons in the Central Flyway since 1975, where …


Managing Nature Reserves For Cranes In China, James Harris Jan 1992

Managing Nature Reserves For Cranes In China, James Harris

Proceedings of the North American Crane Workshop

During the past 15 years, China has established more than 300 nature reserves. Many of the wetland reserves have been created primarily to protect endangered cranes. This paper summarizes the status of 22 nature reserves, 13 for breeding cranes and 9 for wintering cranes. The nature reserves have often been established in areas heavily populated or intensively used for economic purposes. Many reserves have been effective in stopping hunting of cranes. Taking of eggs or young has also been greatly reduced, but general human disturbances threaten successful nesting. Reserve authorities have also taken steps to prevent destruction or degradation of …