Severe Mammal Declines Coincide with Proliferation of Invasive Burmese Pythons in Everglades National Park

Proceedings of the National Academy of Sciences (PNAS)Proceedings of the National Academy of Sciences (PNAS), Published Online 30 January 2012

Michael E. Dorcas, John D. Willson, Robert N. Reed, Ray W. Snow, Michael R. Rochford, Melissa A. Miller, Walter E. Meshaka, Jr., Paul T. Andreadis, Frank J. Mazzotti, Christina M. Romagosa, and Kristen M. Hart

“Invasive species represent a significant threat to global biodiversity and a substantial economic burden. Burmese pythons, giant constricting snakes native to Asia, now are found throughout much of southern Florida, including all of Everglades National Park (ENP). Pythons have increased dramatically in both abundance and geographic range since 2000 and consume a wide variety of mammals and birds. Here we report severe apparent declines in mammal populations that coincide temporally and spatially with the proliferation of pythons in ENP. Before 2000, mammals were encountered frequently during nocturnal road surveys within ENP. In contrast, road surveys totaling 56,971 km from 2003–2011 documented a 99.3% decrease in the frequency of raccoon observations, decreases of 98.9% and 87.5% for opossum and bobcat observations, respectively, and failed to detect rabbits.

Map of South Florida illustrating sampling locations in relation to python distribution.

Map of South Florida illustrating sampling locations in relation to python distribution. Road surveys for mammals were conducted in the 1990s and 2000s along the Main Park Road (MPR) in Everglades National Park (ENP). Areas recently invaded by pythons and surveyed for mammals in 2009–2011 include Big Cypress National Preserve (BCNP), Collier-Seminole State Park (CSSP), Chekika (CHK), and Key Largo. Immokalee and Corbett Wildlife Management Area (CWMA; north of the map) are two sampled sites where pythons have not yet become established. The purple region represents the area of ENP where pythons were found in the 1990s and where reproduction was first reported (16). Red triangles represent localities of pythons found during 2008–2009.

“Road surveys also revealed that these species are more common in areas where pythons have been discovered only recently and are most abundant outside the python’s current introduced range. These findings suggest that predation by pythons has resulted in dramatic declines in mammals within ENP and that introduced apex predators, such as giant constrictors, can exert significant top-down pressure on prey populations. Severe declines in easily observed and/or common mammals, such as raccoons and bobcats, bode poorly for species of conservation concern, which often are more difficult to sample and occur at lower densities.”

Spatio–Temporal Analysis of Urbanization-related Land Use/Cover Dynamics using Satellite Imagery: Case Study Antalya, Turkey

XXII ISPRS Congress, 25 August to 01 September 2012, Melbourne, Australia

Ugur Alganci, Dursun Seker, and Elif Sertel

“The rapid population growth and related urbanization in developing countries mostly affect the metropolitan cities. The urban sprawl that comes with rapid population growth changes land use / cover (LULC) dynamics that mostly results with decrease in natural resources such as forests or pastures and farmlands. In the last decade, a common population growth is observed all over Turkey with increase at 66 provinces out of 81. Antalya is one of the important cities of Turkey that exposed to unplanned urban sprawl. It was at the 29th place according to 1927 population census while it rose to 7th place according to 2000 census results. According to “9th Progress Report” issued by Ministry of Development, Antalya is the city that exposed to fastest population growth with a rate of %0, 48 during 1990-2000.
Antalya is the most popular touristic city of the Turkey, with its 650 km of coastline, appropriate climatic conditions, historical and natural beauties. Its population has increased due to employment facilities and migration related to tourism. It is also a n important agricultural center with its fertile soil and rainy climate. Development in industry and building trade also results with continuous development and rapid urbanization. Main effects of population growth and related urbanization are; change of watersheds, forests and agricultural lands into settlement in an irregular and uncontrolled way and urban sprawl.

“In terms of effective analysis of urbanization; determination of spatial distribution and trend, effects on other land cover types and relationship between topographic parameters become very important. At this point, spatial and topographic information derived from satellite imagery can be used as main data resources. Images obtained from optical satellites that are capable of observing large areas fastly and repeatedly, have been used for decomposition of land cover types and time dependent changes of them depending on spatial, spectral and temporal resolution capabilities. Spatio-temporal analysis of satellite images provides valuable information about changes in LULC dynamics.

“In this research, the effects of urban sprawl over LULC dynamics of Antalya were investigated in terms of spatial and areal changes using multitemporal satellite imagery. Landsat 5 TM images belonging to 1984, 2001 and 2010 were subjected to registration and supervised classification process. LULC information derived from these analyses was used for areal changes between years. Topographic parameters such as aspect and slope were produced from ASTER GDEM data at the same time. After applying a raster –vector conversation to whole dataset, relationship between LULC changes and spatial-topographic characteristics of the area was determined.”


Rangeland Monitoring Using Remote Sensing and GIS: A Case Study of Scale and Resolution in Measuring Plant Community Structure

Society for Range Management ConferenceSociety for Range Management Conference, Spokane, WA, 28 January to 03 February 2012

Ammon Boswell, Steven Petersen, Ryan Jensen, Danny Summers, and Jason Vernon

“Long-term rangeland monitoring is essential for land managers to make informed and effective decisions. However, most management agencies are responsible for extensive areas, making effective monitoring both time consuming and expensive. Therefore, methods are needed for rangeland monitoring that are rapid, cost effective, accurate and robust. Remote sensing and GIS are tools that have been suggested to provide similar results of plant and bare ground cover as ground-based reference data with an acceptable amount of error. The purpose of this study is to compare plant community data obtained from four different remote sensing platforms with ground reference data collected from field plots in northern Utah. Remote Sensing platforms include Landsat (30m), NAIP (1m), High Resolution remote sensed imagery (0.26m), and very high resolution remote sensed imagery (0.06cm), Total percent cover were determined for trees, shrubs, herbaceous plants, and percent bare ground from each data source. Preliminary results indicate that total tree and shrub cover are discernable from high resolution imagery. Herbaceous plants and percent bare ground were more difficult to discern in comparison to ground-based reference data. This may be due to differences in vegetation sampling techniques. Using remote sensing, managers can monitor broader landscapes at more frequent intervals making it possible to effectively monitor plant community change, the invasion of weedy species, and the effects of disturbance on ecological structure.”

New Book — Practicing Geography: Careers for Enhancing Society and the Environment

Practicing Geography Whether you are just beginning as a major, taking classes toward a GIS certificate, working on an advanced degree, or considering a career change, geography can lead to exceptional career opportunities.

Practicing Geography is about making the most of these opportunities. Geographers are in demand in business, government, nonprofit and education sectors for the range of knowledge, abilities and skills they bring to their work. The book addresses how to explore, prepare, and advance in your career and how to deal with related challenges you will face in your work and life.


Preface: A World of Opportunity: Discovering and Managing Careers in Geography, Michael Solem, Kenneth Foote, and Janice Monk

SECTION I: Preparing for a Career in Business, Government, and Nonprofit Organizations
Chapter 1: Part Strategy and Serendipity: A Candid Guide to Career Planning for Geographers, Alyson L. Greiner and Thomas A. Wikle
Chapter 2: Geography Education and Career Readiness, Joy K. Adams, Niem Tu Huynh, Joseph J. Kerski, and G. Brent Hall
Chapter 3: Switching Sectors: Transitioning into and among Business, Government, and Nonprofit Careers, Joy K. Adams
Chapter 4: The Value of An Internship Experience For Early Career Geographers, R. Denise Blanchard, Mark L. Carter, Robert B. Kent, Christopher A. Badurek
Chapter 5: Professional Networking, Tina Cary

SECTION II: Understanding Career Opportunities
Chapter 6: Geography Careers in State and Local Government, William M. Bass and Richard D. Quodomine
Chapter 7: Emerging and Expanding Career Opportunities in the Federal Government, Allison M. Williams, Molly E. Brown, Erin Moriarty, and John A. Wertman
Chapter 8: Geography Careers in Large Businesses and Corporations, Amy J. Blatt and Michael F. Ziolkowski
Chapter 9: Geography and the Nonprofit Sector, Lia D. Shimada and Jeremy Tasch
Chapter 10: Starting a Small Geography Business, Kelsey Brain
Chapter 11: Going Global: Practicing Geography Internationally, Carrie Mitchell and Mélanie Robertson
Chapter 12: Teaching Geography Inside and Outside the Classroom, Susan M. Heffron
Chapter 13: Geography Careers in Consulting, Susanne C. Moser and Angela J. Donelson

SECTION III: Achieving Career Satisfaction Now and Into the Future
Chapter 14: “Work” and “Life”: Crossing Boundaries of Time, Space, and Place, Janice Monk
Chapter 15: Practical Ethics for Professional Geographers, Francis Harvey
Chapter 16: Creating the Life You Want: Lifelong Professional Development for Geographers, Pauline E. Kneale and Larch Maxey

This book also introduces you to dozens of geographers applying their knowledge, skills and perspectives in communities, businesses, government agencies and nonprofit organizations both domestically and internationally. These profiles highlight the diversity of geography and geographers and show in practical terms the decisions real people make about their work and careers.

As a supplement to this book, additional profiles and career resources are available at

You can order your copy of Practicing Geography at

Spatio-temporal Analysis of Groundwater Resource using GIS: A Case Study of Murshidabad District, West Bengal, India

Golden Research ThoughtsGolden Research Thoughts, Volume I, Issue VIII, February 2012

Debabrata Mondal

“In modern time, Geographic Information System (GIS) has been considered as a powerful tool in mapping of ground water resources. The study area Murshidabad district has experienced a remarkable change in ground water table throughout the decades. The present paper is an attempt to evaluate the decadal trend of ground water fluctuation in several blocks of the district along with their possible causes by using the data from secondary sources and processed them through GIS software.

“Groundwater is the only reliable water resource for domestic, as well as for agriculture practice in those countries where rainfall is erratic. Since the country of India has its economic base lying on agricultural sector, a major emphasis has been given to accelerate the agricultural production without concerning the environmental issues for feeding its huge population. From the last few decades gradual depletion of groundwater supplies as a consequence of continued population growth and initiation of Boro cultivation over the Gangetic moribund delta has now been considered as an emerging problem. Now a day’s Murshidabad district is also facing this invisible hazard of groundwater depletion. In this regard monitoring, analyzing of groundwater is necessary for assessing its quantity.                                                                                                                                                                                                                                                                                                                     “Ground water fluctuation map is an important tool for analyzing the temporal as well as spatial changing pattern of groundwater resources. In this regard Geographic Information System (GIS) plays a crucial role for analyzing, model building and interpreting the groundwater data. In order to obtain long term groundwater information, GIS has been used in this study to visually and spatially analyze groundwater data.”

A Remote Sensing Approach for Evaluating Brush Management Caused Transitions between Vegetation States

Society for Range Management ConferenceSociety for Range Management Conference, Spokane, WA, 28 January to 03 February 2012

Sapana Lohani, Chandra Holifield Collins, Philip Heilman, and Ronald L. Tiller

“State and transition models (STMs) have been gaining momentum in rangeland management. STMs are theoretical depictions of the variation due to climate, management, or both, of stable plant communities within ecological sites. For widespread application, maps of the vegetation states presented within these models are needed to allow managers to not only make better informed decisions about what management practices to employ to improve or maintain their rangelands, but to assess the effectiveness of management practices. This study used high-resolution satellite imagery and ground-based data to map vegetation states within identified ecological sites on the Empire Ranch, located within the Las Cienegas National Conservation Area (LCNCA) in southeastern Arizona. The resulting state map was used to assess the effectiveness of brush management practices to drive vegetation communities on several ecological sites from one state to another. The combination of remotely-sensed images, field monitoring, and state and transition models shows great potential as a means of mapping states and evaluating the benefits of established management practices to drive transitions from one vegetation state to another across large areas.”

Selection Indicates Preference in Diverse Habitats: A Ground-Nesting Bird (Charadrius melodus) Using Reservoir Shoreline

PLoS ONE 7(1), Published 27 January 2012

Michael J. Anteau, Mark H. Sherfy, and Mark T. Wiltermuth

“Animals use proximate cues to select resources that maximize individual fitness. When animals have a diverse array of available habitats, those selected could give insights into true habitat preferences. Since the construction of the Garrison Dam on the Missouri River in North Dakota, Lake Sakakawea (SAK) has become an important breeding area for federally threatened piping plovers (Charadrius melodus; hereafter plovers). We used conditional logistic regression to examine nest-site selection at fine scales (1, 3, and 10 m) during summers 2006–2009 by comparing characteristics at 351 nests to those of 668 random sites within nesting territories. Plovers selected sites (1 m2) that were lower than unused random sites, increasing the risk of nest inundation. Plovers selected nest sites that were flat, had little silt, and at least 1 cobble; they also selected for 3-m radius nest areas that were relatively flat and devoid of vegetation and litter. Ninety percent of nests had <38% coverage of silt and <10% slope at the site, and <15% coverage of vegetation or litter and <31% slope within the 3-m radius. Gravel was selected for at nest sites (11% median), but against in the area 10-m from the nest, suggesting plovers select for patches or strips of gravel. Although elevation is rarely evaluated in studies of ground-nesting birds, our results underscore its importance in habitat-selection studies. Relative to where plovers historically nested, habitat at SAK has more diverse topography, substrate composition, vegetation communities, and greater water-level fluctuations. Accordingly, our results provide an example of how habitat-selection results can be interpreted as habitat preferences because they are not influenced by desired habitats being scarce or absent. Further, our results will be useful for directing habitat conservation for plovers and interpreting other habitat-selection studies.”


Spatio-temporal Analysis and Interpolation of PM10 Measurements in Europe

ETC/ACM Technical Paper 2011/10, Released: 2012/01/30

Benedikt Gräler, Lydia Gerharz, and Edzer Pebesma

“This study investigates the potential of spatio-temporal kriging approaches for daily mean PM10 concentrations. The methods used include separate daily variogram estimates, temporally evolving variograms, the metric model, the separable covariance model and the product-sum model, and are combined with multiple linear regression. These methods are applied to daily mean rural background PM10 concentrations across Europe for the year 2005, and incorporate daily EMEP model data and elevation data as predictors.

 Interpolated maps for daily PM10  concentration from May 1 to 9, 2005.

Interpolated maps for daily PM10 concentration from May 1 to 9, 2005.

“The air quality indicators used in this study are the daily and yearly mean PM10 concentrations and the number of days exceeding the limit value 50 µg/m³ (NOE). The quality assessment of the different techniques relies on a cross-validation. Statistical measures are used to quantify the improvement for different indicators.

“It is shown that daily interpolations can improve the statistical performance of the interpolation of annual mean PM10 concentrations. Furthermore, some advantages of daily estimates are described. Besides the improvement in annual mean PM10 concentration maps, studying the phenomenon in a wider spatio-temporal context becomes possible with daily estimates. Especially the estimation the number of days PM10 concentrations exceed certain limits can be done in a more natural way. Likewise, the detection of outliers and data inhomogeneity benefits from a daily spatio-temporal model.

“Interpolation with the simple spatio-temporal variogram models used here exploits the temporal correlations present and out performs the purely spatial interpolation methods. Based on temporal variability of the spatial short-distance variation component, a discussion is given on the suitability of this statistic to infer measurement errors, and alternative approaches are proposed.”