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Publications

These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16731

Toxicological assessment of aquatic ecosystems: application to watercraft contaminants in shallow water environments Toxicological assessment of aquatic ecosystems: application to watercraft contaminants in shallow water environments

Recreational boating and personal watercraft use have the potential to adversely impact shallow water systems through contaminant release and physical disturbance of bottom sediments. These nearshore areas are often already degraded by surface runoff, municipal and industrial effluents, and other anthropogenic activities. For proper management, information is needed on the level of...
Authors
P. V. Winger

Monitoring tigers and prey: conservation needs and managerial constraints Monitoring tigers and prey: conservation needs and managerial constraints

Contents: -- Introduction -- The sampling-based approach to monitoring -- Defining objectives -- Assessing available resources -- Decision making: Matching objectives and resources -- References
Authors
K. U. Karanth, J.D. Nichols, P.K. Sen, V. Rishi

The use of resighting data to estimate the rate of population growth of the snail kite in Florida The use of resighting data to estimate the rate of population growth of the snail kite in Florida

The rate of population growth (lambda) is an important demographic parameter used to assess the viability of a population and to develop management and conservation agendas. We examined the use of resighting data to estimate lambda for the snail kite population in Florida from 1997-2000. The analyses consisted of (1) a robust design approach that derives an estimate of lambda from...
Authors
V.J. Dreitz, J.D. Nichols, J.E. Hines, R.E. Bennetts, W.M. Kitchens, D.L. DeAngelis

Investigations of potential bias in the estimation of lambda using Pradel's (1996) model for capture-recapture data Investigations of potential bias in the estimation of lambda using Pradel's (1996) model for capture-recapture data

Pradel's (1996) temporal symmetry model permitting direct estimation and modelling of population growth rate, lambda sub i provides a potentially useful tool for the study of population dynamics using marked animals. Because of its recent publication date, the approach has not seen much use, and there have been virtually no investigations directed at robustness of the resulting...
Authors
J.E. Hines, J.D. Nichols

Role of selenium toxicity and oxidative stress in aquatic birds Role of selenium toxicity and oxidative stress in aquatic birds

Adverse effects of selenium (Se) in wild aquatic birds have been documented as a consequence of pollution of the aquatic environment by subsurface agricultural drainwater and other sources. These effects include mortality, impaired reproduction with teratogenesis, reduced growth, histopathological lesions and alterations in hepatic glutathione metabolism. A review is provided, relating...
Authors
D. J. Hoffman

Prey of the Peregrine Falcon (Falco peregrinus cassini) in Southern Argentina and Chile Prey of the Peregrine Falcon (Falco peregrinus cassini) in Southern Argentina and Chile

The Peregrine Falcon (Falco peregrinus cassini) in Patagonia attracted wide interest two decades ago when there was a focus on determining the taxonomic position of the Pallid Falcon (also called Kleinschmidt's falcon and Tierra del Fuego falcon; formerly named Falco kreyenborgi). In 1981, however, the pallid falcon was confirmed to be a pale color morph of the peregrine, and since that...
Authors
D. H. Ellis, B.A. Sabo, J.K. Fackler, B.A. Millsap

Global climate change and vector-borne diseases Global climate change and vector-borne diseases

Global warming will have different effects on different diseases because of the complex and idiosynchratic interactions between vectors, hosts, and pathogens that influence transmission dynamics of each pathogen. Human activities, including urbanization, rapid global travel, and vector management, have profound effects on disease transmission that can operate on more rapid time scales...
Authors
H. S. Ginsberg

An evaluation of population index and estimation techniques for tadpoles in desert pools An evaluation of population index and estimation techniques for tadpoles in desert pools

Using visual (VI) and dip net indices (DI) and double-observer (DOE), removal (RE), and neutral red dye capture-recapture (CRE) estimates, we counted, estimated, and censused Couch's spadefoot (Scaphiopus couchii) and canyon treefrog (Hyla arenicolor) tadpole populations in Big Bend National Park, Texas. Initial dye experiments helped us determine appropriate dye concentrations and...
Authors
Robin E. Jung, Gage H. Dayton, Stephen J. Williamson, John R. Sauer, Sam Droege

The Protected Areas Visitor Impact Management (PAVIM) framework: A simplified process for making management decisions The Protected Areas Visitor Impact Management (PAVIM) framework: A simplified process for making management decisions

Ecotourism and protected area visitation in Central and South America have resulted in ecological impacts, which some protected areas managers have addressed by employing visitor impact management frameworks. In this paper, we propose the Protected Area Visitor Impact Management (PAVIM) framework as an alternative to carrying capacity and other frameworks such as Limits of Acceptable...
Authors
T. A. Farrell, Jeffrey L. Marion

Longevity records and survival estimate of birds in a Guatemala rain forest Longevity records and survival estimate of birds in a Guatemala rain forest

Birds were mist-netted for ten consecutive 'winter' seasons at two sites on Cerro San Gil and for three to nine seasons at eight other sites on the mountain. Sixteen nets were used at each site for three days; net locations were the same each year. From 1,255 subsequent-year recaptures we computed annual survival using the program MARK. A low annual survival of 0.26+0.03 for Long-tailed...
Authors
C.S. Robbins, B. Dowell, J. Hines

Producing progeny from endangered birds of prey: Treatment of urine-contaminated semen and a novel intramagnal insemination approach Producing progeny from endangered birds of prey: Treatment of urine-contaminated semen and a novel intramagnal insemination approach

Wild raptors brought into an ex situ environment often have poor semen quality that is further compromised by urine contamination. Generally, it is believed that in birds, artificial insemination into the cloaca or caudal vagina of females requires large doses of high-quality spermatozoa to maximize fertility. In an effort to define and overcome some of the challenges associated with...
Authors
J.M. Blanco, G.F. Gee, D.E. Wildt, A.M. Donoghue
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