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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Revisão taxonômica das espécies de Bufo do complexo granulosus (Amphibia, Anura, Bufonidae)

Narvaes, Patrícia. January 2003 (has links)
Thesis (doctoral)--Universidade de São Paulo, 2003. / Title from PDF t.p. (viewed on May 21, 2006). Includes bibliographical references (p. 215-240).
2

Evolution and impact of invasive species cane toads and snakes in Australia /

Phillips, Ben L. January 2004 (has links)
Thesis (Ph. D.)--University of Sydney, 2005. / Title from title screen (viewed 20 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Biological Sciences, Faculty of Science. Degree awarded 2005; thesis submitted 2004. Includes bibliographical references. Also available in print form.
3

Společenstva obojživelníků a jejich ochrana na lokalitě Vojenské cvičiště Rokycany

Kalousová, Štěpánka January 2006 (has links)
No description available.
4

Social foraging in Bufo Americanus tadpoles

Sontag, Charles Robert. January 2007 (has links)
Thesis (Ph. D.)--State University of New York at Binghamton, Department of Biological Sciences, 2007. / Includes bibliographical references.
5

Promene trofičkih karakteristika obične krastače Bufo bufo, Mertens and Müller, 1928 (Bufonidae: Anura) tokom postmetamorfoze / Changes in trophic characteristics of common toad Bufo bufo, Mertens and Müller, 1928 (Bufonidae: Anura) during postmetamorphosis

Čađenović Natalija 10 October 2014 (has links)
<p>Analiza ishrane je urađena na uzorcima 16 populacija vrste <em>Bufo bufo</em>, sa&nbsp;ukupno 356 adultnih jedinki. Od toga 8 uzoraka pripada podvrsti<em> B.b. bufo</em>-populacija sa 158, a 8 uzoraka <em>B.b spinosus</em> populacija sa 198 jedinki. Za analizu&nbsp;ishrane je kori&scaron;ćen i uzorak od 150 primjeraka, tek metamorfoziranih jedinki.&nbsp;Uzorci populacija su prikupljeni sa teritorije Srbije i Crne Gore. Ishranu ispitivanih&nbsp;podvrsta roda <em>Bufo</em>, na svim lokalitetima čine jedinke plijena isključivo predstavnici&nbsp;Invertebrata. Kod obje podvrste dominantan plijen su pripadnici reda Coleoptera i&nbsp;Hymenoptera kod <em>B.b. spinosus&nbsp;</em>(70,05%,16,92%), &nbsp;kod <em>B.b. bufo&nbsp;</em>(59,69%, 22,61%).&nbsp;Multivarijantna analiza urađena na ukupnom uzorku pokazujeda postoji statistički&nbsp;značajna zavisnost ispitivanih morfolo&scaron;kih karaktera žaba i promjenljive&nbsp;morfologije plijena. Korespodentna analiza je pokazala da jedinke obje &nbsp;podvrste&nbsp;preferiraju sličan plijen samo &scaron;to je učestalost tog plijena različita po podvrstama i&nbsp;polovima. Kod tek metamorfoziranih jedinki Anura na oba lokaliteta prisutan je isti&nbsp;plijen sa malim procentualnim razlikama. Prisustvo relativno visokog procenta&nbsp;Chironomidae ukazuje da ove jedinke nisu u potpunosti pre&scaron;le na terestrični način&nbsp;života. Dok prisustvo visokog procenta familija Formicidae i Byrrhidae ukazuje na&nbsp;<br />ishranu kojoj inače teže pripadnici vrste <em>B. bufo</em>, prelaskom na terestrični način&nbsp;života. Vrijednosti &scaron;irina trofičkih ni&scaron;a (B<sub>A</sub>) po podvrstama pokazuju da je podvrsta <em>B.b. spinosus</em><i>&nbsp;</i>(B<sub>1</sub>A=0,15) imala neznatno manju vrijednost u odnosu na podvrstu&nbsp;<em>B.b. bufo</em> (B<sub>1</sub>A=0,16) , &scaron;to ukazuje na to da su pripadnici obje podvrste imale&nbsp;prilično ujednačenu ishranu. Na osnovu taksonomije plijena zabilježeno je veoma&nbsp;visoko preklapanje ni&scaron;a ishrane između podvrsta (95%). Veoma su oskudni&nbsp;literaturni podaci o ishrani ove dvije podvrste, &scaron;to podatke i rezultate ovog rada čini&nbsp;posebno vrijednim.</p> / <p>Diet analysis was conducted on the samples of 16 populations of species&nbsp;<em>Bufo bufo</em>, &nbsp;with total of 356 adult individuals. Among that, 8 samples belonged to&nbsp;sub-species <em>B.b. bufo</em> &ndash; population with 158 samples, and another 8 samples&nbsp;belonged to <em>B.b. spinosus</em>, with population of 198 individuals. For diet analysis we&nbsp;also used the sample of 150 individuals which have just finished metamorphosis.&nbsp;Population samples were collected from the territories of Serbia and Montenegro.&nbsp;The diet of investigated subspecies belonging to the genus <em>Bufo</em> from all localities,&nbsp;was composed of the Invertebrata exclusively. Coleoptera and Hymenoptera were dominant prey items in both groups <em>B.b. spinosus&nbsp;</em>(70.05%, 16.92%), and <em>B.b. bufo&nbsp;</em>(59.69%, 22.61%). Multivariate statistical analysis which was performed on the&nbsp;entire sample, showed existence of statistically significant dependence of&nbsp;morphological traits of common toadand variable morphology of prey. &nbsp;Correspondent analysis showed that individuals of both subspecies prefer similar&nbsp;prey, but the frequency of the prey occurance at different subspecies and sexes is&nbsp;different. Recently metamorphosed Anuran individuals from both localities, take&nbsp;the same prey with a small differences inpercentage. The presence of a relatively&nbsp;high percentage of Chironomidae indicates that these individuals are not completely&nbsp;moved on to terrestrial life. While the presence of a high percentage of the families&nbsp;Formicidae and Byrrhidae indicates a diet which usually species <em>B. bufo </em>aspire&nbsp;during the transition to terrestrial life. Values (B<sub>A</sub>) of trophic niche width (B<sub>A</sub>)&nbsp;indicate that the subspecies <em>B.b. spinosus&nbsp;</em>(B<sub>A</sub> =15) had a slightly lower value&nbsp;compared to subspecies <em>B.b. bufo</em> (B<sub>A</sub> =15) which indicates that both subspecies had&nbsp;a fairly uniform diet. Based on the taxonomy of prey, very high dietary &nbsp;niche&nbsp;overlap between subspecies was recorded (95%). Since there are very scarce&nbsp;<br />literature data about diet of the two subspecies, the data and results of this thesis are&nbsp;<br />particularly valuable.&nbsp;</p>
6

A GIS model for identifying potential breeding habitat for the Houston Toad (Bufo houstonensis) /

Buzo, Daniela, January 1900 (has links)
Thesis (M.S.)--Texas State University-San Marcos, 2008. / Vita. Appendix: leaves 73-89. Includes bibliographical references (leaves 90-93). Also available on microfilm.
7

Studium obojživelníků (Amphibia) v Moravském krasu

Chalupková, Kateřina January 2006 (has links)
No description available.
8

Inventering av Strandpadda (Bufo calamita) 2012 på Balgö och inom Varbergs kust

Larsson, Matilda January 2012 (has links)
No description available.
9

Community assembly of xeric-adapted anurans at multiple spatial scales

Dayton, Gage Hart 12 April 2006 (has links)
The distribution and abundance of organisms is influenced by historical, abiotic, and biotic factors. The goal of my dissertation was to determine the distribution of anurans in the Big Bend region of the Chihuahuan Desert and to examine how abiotic and biotic factors shape the composition and structure of anuran communities at multiple spatial scales. My approach relied on extensive field surveys, laboratory and field experiments, and GIS modeling. Results from field surveys and reciprocal transplant studies of tadpoles indicate that abiotic conditions of the breeding site most likely do not play a significant role in causing the segregation of species among individual breeding pools. I used laboratory and mesocosm experiments to test for indirect and direct effects of predators on growth and survival of S. couchii tadpoles. I found that S. couchii tadpoles do not alter their behavior in the presence of predators and are very susceptible to predation. Although tadpoles reared with predators suffered high mortality rates, they metamorphosed significantly faster than tadpoles reared without predators. The reduced time to metamorphose is likely a result of the thinning of intraspecific competitors. Because the primary cause of death for S. couchii tadpoles is desiccation due to pond drying, predators may play an important role in facilitating metamorphosis by decreasing competitors and thus increasing per capita resources, therefore decreasing time to metamorphosis for the surviving tadpoles. At the landscape level anuran distributions seem to be influenced by environmental factors that influence the survival of the adult stage. At the level of the breeding site, microhabitat and abiotic components of the aquatic environment do not seem to play an important role in influencing breeding site use by different species. Rather, it seems likely that predation on tadpoles by predators is important in limiting the distribution of some species and that the fast-developing S. couchii may exclude other species from using sites via oophagy and predation on small tadpoles. My research elucidates the fact that in order to understand factors important in regulating ecological communities it is important to examine both abiotic and biotic factors at multiple spatial scales.
10

Factors promoting variation in feeding morphology of larval southern toads (Bufo terrestris)

Schacht, Matthew C. January 2009 (has links)
Thesis (M.S.)--Georgia Southern University, 2009. / "A thesis submitted to the Graduate Faculty of Georgia Southern University in partial fulfillment of the requirements for the degree Master of Science." Directed by Lance McBrayer. ETD. Includes bibliographical references (p. 76-80) and appendices.

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