Drought and Grazing III: Root Dynamics and Germinable Seed Bank by A.L
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Predation by Gray Catbird on Brown Thrasher Eggs
March 2004 Notes 101 PREDATION BY GRAY CATBIRD ON BROWN THRASHER EGGS JAMES W. RIVERS* AND BRETT K. SANDERCOCK Kansas Cooperative Fish and Wildlife Research Unit, Division of Biology, Kansas State University, Manhattan, KS 66506 (JWR) Division of Biology, Kansas State University, Manhattan, KS 66506 (BKS) Present address of JWR: Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA 93106 *Correspondent: [email protected] ABSTRACT The gray catbird (Dumetella carolinensis) has been documented visiting and breaking the eggs of arti®cial nests, but the implications of such observations are unclear because there is little cost in depredating an undefended nest. During the summer of 2001 at Konza Prairie Bio- logical Station, Kansas, we videotaped a gray catbird that broke and consumed at least 1 egg in a brown thrasher (Toxostoma rufum) nest. Our observation was consistent with egg predation because the catbird consumed the contents of the damaged egg after breaking it. The large difference in body mass suggests that a catbird (37 g) destroying eggs in a thrasher (69 g) nest might risk injury if caught in the act of predation and might explain why egg predation by catbirds has been poorly documented. Our observation indicated that the catbird should be considered as an egg predator of natural nests and that single-egg predation of songbird nests should not be attributed to egg removal by female brown-headed cowbirds (Molothrus ater) without additional evidence. RESUMEN El paÂjaro gato gris (Dumetella carolinensis) ha sido documentado visitando y rompien- do los huevos de nidos arti®ciales, pero las implicaciones de dichas observaciones no son claras porque hay poco costo por depredar un nido sin defensa. -
Debris the Science and Changing Perceptions of Dead Trees by Alexander Evans and Robert Perschel
An Appreciation of Debris The Science and Changing Perceptions of Dead Trees By Alexander Evans and Robert Perschel oarse woody debris. To most people, two Coarse woody debris (CWD) is wood in the forest that’s no of the three words in that phrase have longer part of a living tree. Rather than being dead, this wood negative connotations. Debris is the worst is an important source of life in the forest. Foresters who value offender, suggesting random junk strewn it for its ecological functions have been searching for new terms about. When the debris is coarse, it’s even for CWD, and you’ll hear it referred to as biomass, dead wood, worse – it’s unrefined, it’s big. coarse woody material, and even retained organic matter. VIRGINIA BARLOW 44 Northern Woodlands / Winter 2008 Harry Dwyer, a forester in Fayette, Maine, likens the lan- as a seed bed for trees and plants, a mulch layer, and a slow- guage predicament to that of another formerly maligned mate- release fertilizer. Decomposing fungi depend on dead wood for rial: garden waste. He said, “You could look at a pile of rotting nutrients and moisture, and in turn many trees rely on mutu- vegetables as garbage, or you could note its value and call it alistic relationships with mycorrhizal fungi. Nitrogen fixation compost.” Digging into a rotten log in his woodlot, Dwyer in CWM by microbes (both anaerobic and microaerophyllic displays some of the dark, wet material in his hand. “It doesn’t bacteria) provides this important element in both terrestrial matter what you call this – coarse woody debris, coarse woody and aquatic ecosystems. -
AN ABSTRACT of the THESIS of Douglas William Havlina for The
AN ABSTRACT OF THE THESIS OF Douglas William Havlina for the degree of Master of Science in Rangeland Resources presented on January 27, 1995 Title: Fire Effects on Vegetation Diversity, Structure, and Successional Dynamics in Shrub-Steppe and Mixed Conifer Environments of the Hells Canyon, Idaho. Abstract approved: The effects of fire severity on post-fire succession and shrub demography were quantified in shrub-steppe grasslands and subalpine forests in the Hells Canyon of the Payette National Forest, Idaho. Following the 1988 Eagle Bar Fire, species frequency, community diversity, fire adaptations, and stand ages were quantified at 12 plots in burned and unburned forests. Pre-fire composition was dominated by Pseudotsuga menziesii, Pinus contorta, Abies grandis, and Abies lasiocarpa in the overstory. Pre- fire basal area ranged from 41 to 80 m 2 ha-1 . Pre-fire stand ages ranged from 71 years in Abies lasiocarpa forests to > 200 years in Pseudotsuga menziesii stands. Fire scenarios which were sampled consisted of: (1) complete stand-replacement fires; (2) partial stand- replacement fires; and (3) unburned forests (control). Partial stand-replacement forests were characterized by significantly higher mean species diversity and richness (H'=3.16, S=36) than complete stand-replacement (H'=2.78, S=27) or unburned forests (H=2.26, S=15). Vegetation preferentially established in burned areas along a gradient of fire severity according to adapted fire guilds. Single-storied forests dominated by Pinus contorta and Abies lasiocarpa typified stand-replacement fire scenarios, with mean ages ranging from 99 to 159 years corresponding to fire return intervals common in this type. -
Abstracts from the 1999 Symposium
UTAH I THE I DESERT TORTOISE COUNCIL ARIZONA NEVADA l I i I / + S v'LEI S % A|. w a CALIFORNIA PROCEEDINGS OF 1999 SYMPOSIUM DESERT TORTOISE COUNCIL PROCEEDINGS OF THE 1999 SYMPOSIUM A compilation of reports and papers presented at the twenty-fourth annual symposium of the Desert Tortoise Council, March 5-8, 1999 St. George, Utah PUBLICATIONS OF THE DESERT TORTOISE COUNCIL, INC. Members Non-members Proceedings of the 1976 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1977 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1978 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1979 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1980 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1981 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1982 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1983 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1984 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1985 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1986 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1987-91 Desert Tortoise Council Symposia $20,00 $20.00 Proceedings of the 1992 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1993 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1994 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1995 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1996 Desert Tortoise Council Symposium $10.00 $15.00 Proceedings of the 1997-98 Desert Tortoise Council Symposia $10.00 $15.00 Annotated Bibliog raphy of the Desert Tortoise, Gopherus agassizii $10.00 $15.00 Note: Please add $1.00 per copy to cover postage and handling. -
Influence of Coarse Woody Debris on Seedlings and Saplings in A
INFLUENCE OF COARSE WOODY DEBRIS ON SEEDLINGS AND SAPLINGS IN A PINUS PALUSTRIS WOODLAND by ALEXANDRA LOGAN JUSTIN L. HART, COMMITTEE CHAIR MATTHEW C. LAFEVOR ARVIND A.R. BHUTA A THESIS Submitted in partial fulfillment of the requirements for the degree of Master of Science in the Department of Geography in the Graduate School of The University of Alabama TUSCALOOSA, ALABAMA 2020 Copyright Alexandra Logan 2020 ALL RIGHTS RESERVED 2 ABSTRACT Coarse woody debris (CWD) has beneficial effects on plant growth and establishment. Longleaf pine (Pinus palustris Mill.) stands support relatively low amounts of CWD — 2 to 30 m3 ha-1. In April 2011, an EF3 tornado passed through the Oakmulgee Ranger District of the Talladega National Forest in the Fall Line Hills of Alabama. This disturbance resulted in the large addition of CWD to a longleaf pine woodland, and a rare opportunity to analyze how CWD can influence a managed, pine woodland. The goal of this study was to examine the effect of CWD on woody plant richness, density, and growth rate (quantified by height) in a longleaf pine woodland that experienced a catastrophic wind disturbance. A total of three 1 m2 quadrats were established against either side of a piece of CWD (> 3 m in length and ≥ 10 cm in diameter). Another quadrat was established at least 3 m away from the focal CWD piece. For each plot, the presence and height of every woody plant (< 5 cm dbh) were recorded. Sapling density, oak and hickory density, and organic matter were all found to be significantly higher in quadrats adjacent to CWD than away (all p < 0.05). -
Forest Fragment Size and Microhabitat Effects on Palm Seed Predation
BIOLOGICAL CONSERVATION 131 (2006) 1– 13 available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/biocon Forest fragment size and microhabitat effects on palm seed predation Marina Fleurya,b,c,*, Mauro Galettib,c aLaborato´rio de Ecologia e Restaurac¸a˜ o Florestal (LERF), Escola Superior de Agricultura ‘‘Luiz de Queiroz’’, Universidade de Sa˜ o Paulo (ESALQ/USP), Brazil bLaborato´rio de Biologia da Conservac¸a˜ o, Grupo de Fenologia e Dispersa˜ o de Sementes, Departamento de Ecologia, Universidade Estadual Paulista (UNESP), C.P. 199, 13506-900, Rio Claro, Sa˜ o Paulo, Brazil cInstituto de Biologia da Conservac¸a˜ o (IBC), Av.P-13, 293, Rio Claro, SP, Brazil ARTICLE INFO ABSTRACT Article history: The establishment of plant species depends crucially on where the seeds are deposited. How- Received 11 January 2005 ever, since most studies have been conducted in continuous forests, not much is known about Received in revised form the effects of forest fragmentation on the maintenance of abiotic and biotic characteristics in 19 October 2005 microhabitats and their effects on seed survival. In this study, we evaluated the effects of for- Accepted 24 October 2005 est fragmentation on the predation upon the seeds of the palm Syagrus romanzoffiana in three Available online 3 April 2006 microhabitats (interior forest, forest edge and gaps) in eight fragments of semi-deciduous Atlantic forest ranging in size from 9.5 ha to 33,845 ha in southeastern Brazil. Specifically, Keywords: we examined the influence of the microhabitat structure, fauna and fragment size on the pat- Arecaceae tern of seed predation. -
Effects of Trail Traffic on Egg-Predation by Mammal Populations in the Monteverde Cloud Forest Preserve
Effects of trail traffic on egg-predation by mammal populations in the Monteverde Cloud Forest Preserve. Karmen Scott Department of Environmental Science, University of Oregon ABSTRACT The effects of human traffic within trails on egg predation and predatory mammal compositions between heavily trafficked trails and secluded trails were studied at the Monteverde Cloud Forest Preserve. This study was able to find differences in egg-predatory mammal compositions between these two trail types by looking at teeth impressions in eggs made of plasticine. The main predator was found to be Nasura narica (common coati) who was involved in the majority of the egg predation events and the vast majority of the nests preyed upon were on the highly trafficked trail. There were only a few predation events from other mammals such as rodents and Cebus capucinus (white-faced monkey). In this case, the abundance of tourists have altered populations of a mesopredator, Nasua narica by providing a new food source for them (garbage and tourist‟s lunches) and by affecting the rarity of their predators (boas, cats and Tayras) whom steer-clear of human populated areas and therefore steer-clear of N. narica. This dualistic relationship acting on the population of N. narica makes for an increase in the carrying capacity and, hence, further predation. This imbalanced egg- predation by N. narica on tourist trails allocates the disruption of their prey populations. Studies of the impacts of tourism have important conservation implications because tourism can have a tremendous disturbance on structure and community function. RESUMEN Los efectos del tráfico humano en la depredación de huevos en los senderos y en las composiciones de las comunidades de mamíferos depredadores entre los senderos con mucho tránsito y los senderos recluidos fueron estudiados en La Reserva del Bosque Nuboso de Monteverde. -
Department of Sustainability, Environment, Water, Population and Communities; Formerly from Department of Primary Industries, Parks, Water and Environment (Tasmania)
The Minister included this species in the critically endangered category, effective from 26/02/2013. Advice to the Minister for Sustainability, Environment, Water, Population & Communities from the Threatened Species Scientific Committee (the Committee) on amendment to the list of Threatened Species under the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act) 1. Reason for Conservation Assessment by the Committee This advice follows assessment of information gathered through the Commonwealth’s partnership agreement with Tasmania, which is aimed at systematically reviewing species that are inconsistently listed under the EPBC Act and relevant Tasmanian legislation. The Committee provides the following assessment of the appropriateness of this species’ inclusion in the EPBC Act list of threatened species: Corybas sulcatus (grooved helmet-orchid) 2. Summary of Species Details Taxonomy Conventionally accepted as Corybas sulcatus (M.A.Clem. & D.L.Jones) G.N.Backh. Formerly Nematoceras sulcatum M.A.Clem. & D.L.Jones. State/Territory Listing This species is listed as endangered (as Nematoceras Status sulcatum) under the Tasmanian Threatened Species Protection Act 1995. Description A small, deciduous, tuberous terrestrial orchid that forms small clonal colonies. Leaves are solitary, circular (12–20 mm diameter) and flat to shallowly concave. They are light green above and silvery green beneath, with a thick-textured blade and fleshy leaf stalk 12–16 mm long. Flowers are 25–30 mm long and 10–14 mm wide, mostly dark red and held erect on a fleshy, green stalk that is 5–7 mm long (Clements and Jones, 2007). Distribution The grooved helmet-orchid is endemic to Macquarie Island (Tasmania). -
Effects of Predator Satiation on Seed Predation in New Roadside Prairie Plantings
University of Northern Iowa UNI ScholarWorks Dissertations and Theses @ UNI Student Work 2016 Effects of predator satiation on seed predation in new roadside prairie plantings Jessica Riebkes University of Northern Iowa Let us know how access to this document benefits ouy Copyright ©2016 Jessica Riebkes Follow this and additional works at: https://scholarworks.uni.edu/etd Part of the Plant Sciences Commons Recommended Citation Riebkes, Jessica, "Effects of predator satiation on seed predation in new roadside prairie plantings" (2016). Dissertations and Theses @ UNI. 277. https://scholarworks.uni.edu/etd/277 This Open Access Thesis is brought to you for free and open access by the Student Work at UNI ScholarWorks. It has been accepted for inclusion in Dissertations and Theses @ UNI by an authorized administrator of UNI ScholarWorks. For more information, please contact [email protected]. Copyright by JESSICA L. RIEBKES 2016 All Rights Reserved EFFECTS OF PREDATOR SATIATION ON SEED PREDATION IN NEW ROADSIDE PRAIRIE PLANTINGS An Abstract of a Thesis Submitted in Partial Fulfillment Of the Requirements for the Degree Master of Science Jessica Riebkes University of Northern Iowa May 2016 ABSTRACT Restoration efforts in the tallgrass prairie ecosystem are inhibited by high seed cost and as little as 10% emergence of planted, pure live seed. This study examined the portion of loss due to seed predation and sought to reduce this predation in new roadside prairie plantings. Studies document the occurrence of predation in several plant communities and across all plant families, but little is known about how to reduce the impact of seed predators, especially in a restoration setting. -
Environmental Limits Page 1
POST Report 370 January 2011 Living with Environmental Limits Page 1 Summary Human well-being is dependent upon assessment approaches. However, where renewable natural resources. Agricultural there is a risk of thresholds being systems, for example, depend upon plant breached and potentially irreversible productivity, soil, the water cycle, the impacts occurring, additional policy nitrogen, sulphur and phosphorus nutrient safeguards to maintain natural resource cycles and a stable climate. Renewable systems within environmental limits are natural resources can be subject to required. biological and physical thresholds beyond which irreversible changes in benefit Managing ecosystems to maximise one provision may occur. These are difficult to particular benefit, such as food provision, define and many are likely to be identified can result in declines in other benefits. only once crossed. An environmental limit The evidence base is not yet sufficient to is usually interpreted as the point or range determine the most effective ways to of conditions beyond which there is a maintain benefit provision within significant risk of thresholds being environmental limits, but a range of policy exceeded and unacceptable changes responses are seeking to optimise multiple occurring.1 benefit provision, including: Biodiversity loss, climate change and a agri-environment schemes range of other pressures are affecting generic measures to enhance renewable natural resources. If biodiversity, which may increase governments do not effectively monitor the the capacity of natural resource use and degradation of natural resource systems to adapt to environmental systems in national account frameworks, change the probability of costs arising from the use of ecological processes to exploiting natural resources beyond increase overall natural system environmental limits is not taken into resilience to address problems account. -
Egg Predation in Reedbed Nesting Greylag Geese Anser Anser in Vejlerne, Denmark
137 EGG PREDATION IN REEDBED NESTING GREYLAG GEESE ANSER ANSER IN VEJLERNE, DENMARK JENS NYELAND KRISTIANSENl,2 Kristiansen J.N. 1998. Egg predation in reedbed nesting Greylag Geese An ser anser in Vejlerne, Denmark. Ardea 86: 137-145. Egg predation in Greylag Geese Anser anser nesting in reedbeds was stud ied at three sites in Vejlerne (NW Denmark). Overall, 34% of all clutches hatched successfully (range 26-53%), while at least 34% of all nests were abandoned. Avian predation of clutches was particularly high on one site (20%) compared to other sites (0-2%), probably as a result of better breed ing opportunities for crows in that area. Mammalian egg predation was low in the two sites with natural barriers in the form of water channels or with higher vegetation densities. Nests neighbouring depredated nests were more likely to be depredated. An important factor affecting egg predation by mammals was the distance of the nest to reed cutting tracks. Second, there was a tendency for successful nests to occur in areas with higher veg etation densities. Mammalian predators were Red Fox Vulpes vulpes and American Mink Mustela vison and/or Western Polecat M. putorius. Key words: Anser anser - egg predation - reedbed - mammalian predators lThe National Environmental Research Institute, Department of Coastal Zone Ecology, Kal¢, Grenavej 12, DK-8410 R¢nde, Denmark; 2University of Copenhagen, Zoological Institute, Department of Population Biology, Universitetsparken 15, DK-2100 Copenhagen, Denmark, e-mail: JNKris [email protected] INTRODUCTION mammalian predators, or hide their nests in dense vegetation to avoid detection by avian predators. The reproductive output of geese varies greatly This study examined the importance of factors af within and between species (Johnson et al. -
Human Involvement in Food Webs*
EG35CH01-Strong ARI 13 September 2010 10:20 Human Involvement in Food Webs∗ Donald R. Strong1 and Kenneth T. Frank2 1Department of Evolution and Ecology, University of California, Davis, California 95616; email: [email protected] 2Bedford Institute of Oceanography, Ocean Sciences Division, Dartmouth, Nova Scotia B2Y 4A2, Canada; email: [email protected] Annu. Rev. Environ. Resour. 2010. 35:1–23 Key Words First published online as a Review in Advance on bottom-up, fisheries, intraguild predation, mesopredator, top-down, July 1, 2010 trophic cascade The Annual Review of Environment and Resources is online at environ.annualreviews.org Abstract This article’s doi: Human involvement in food webs has been profound, bringing about 10.1146/annurev-environ-031809-133103 enormous and disproportionate losses of large apex predators on land Copyright c 2010 by Annual Reviews. and in water. The losses have modified or even eliminated concatena- All rights reserved tions of indirect interactions propagating from predators to herbivores 1543-5938/10/1121-0001$20.00 to plants, inter alia. Food webs are a synthesis of bottom-up energy and ∗This article was co-authored by an employee of nutrient flow from plant producers to consumers and top-down regula- a British Commonwealth government as part of tion of producers by consumers. The trophic cascade is the simplest top- his official duties and is therefore subject to down interaction and accounts for a great deal of what is known about Crown Copyright. food webs. In three-link cascades, predators suppress herbivores, re- leasing plants. In longer cascades, predators can suppress smaller meso- by UNIVERSITY OF IDAHO LIBRARY on 03/21/11.