{"id":{"repo_id":"cape-town","oai_identifier":"oai:open.uct.ac.za:11427/12721"},"canonical_url":"https://search.dev.ndltd.org/etd/cape-town/oai:open.uct.ac.za:11427/12721","repository":{"repo_id":"cape-town","name":"University of Cape Town","base_url":"https://open.uct.ac.za/oai/request"},"display":{"title":"Searching for answers to the silent decline: first estimates of survival and recruitment for the critically endangered Rose's mountain toadlet, Capensibufo rosei","abstract":"Capensibufo rosei, a critically endangered bufonid found only within Table Mountain National Park, has shown a silent decline over recent decades, despite being found within a protected area with apparently pristine habitat. I estimated the first survival and recruitment rates for the species, using Capture-Mark-Recapture (CMR) methods, over a 7-year period, in order to identify demographic trends over time. I also used covariate models to test whether any observed trends in these demographic parameters were significantly related to variation in rainfall or drought-stress. I found some evidence for an extreme rainfall-induced life-history plasticity, with both survival and recruitment rates covarying closely with rainfall parameters. Although recruitment rate showed a positive relationship with rainfall, the relationship between survival rate and rainfall, specifically during the start of breeding, was negative, with breeding season rainfall explaining 94% of the variability in survival rate over time. I also found evidence to suggest that higher adult survival during poorer breeding rainfall years may be a natural population buffering mechanism to a highly variable microclimate, and that variable rainfall during the start of the breeding season may elicit a variable response in breeding investment by adults. Finally, I found evidence to suggest that the population is small, range-restricted and highly unstable, and that disturbances at the breeding site during good breeding years may cause the population to crash.","abstract_html":"Capensibufo rosei, a critically endangered bufonid found only within Table Mountain National Park, has shown a silent decline over recent decades, despite being found within a protected area with apparently pristine habitat. I estimated the first survival and recruitment rates for the species, using Capture-Mark-Recapture (CMR) methods, over a 7-year period, in order to identify demographic trends over time. I also used covariate models to test whether any observed trends in these demographic parameters were significantly related to variation in rainfall or drought-stress. I found some evidence for an extreme rainfall-induced life-history plasticity, with both survival and recruitment rates covarying closely with rainfall parameters. Although recruitment rate showed a positive relationship with rainfall, the relationship between survival rate and rainfall, specifically during the start of breeding, was negative, with breeding season rainfall explaining 94% of the variability in survival rate over time. I also found evidence to suggest that higher adult survival during poorer breeding rainfall years may be a natural population buffering mechanism to a highly variable microclimate, and that variable rainfall during the start of the breeding season may elicit a variable response in breeding investment by adults. Finally, I found evidence to suggest that the population is small, range-restricted and highly unstable, and that disturbances at the breeding site during good breeding years may cause the population to crash.","abstract_has_math":false,"creators":["Becker, Francois Stephanus"],"institution":"Department of Biological Sciences","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":["Tolley, Krystal A","Altwegg, Res"],"committee_chairs":[],"committee_members":[],"year":2014,"date_issued":"2014","date_published":"2014","updated_at":"2026-07-22T22:23:39Z","subjects":[],"languages":["eng"],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/11427/12721","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.advisor","label":"Advisor","values":["Tolley, Krystal A","Altwegg, Res"]},{"key":"dc:creator","label":"Author","values":["Becker, Francois Stephanus"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2015-05-04T07:13:49Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2015-05-04T07:13:49Z"]},{"key":"dc:date.issued","label":"Date","values":["2014"]},{"key":"dc:publisher.department","label":"Dc Publisher Department","values":["Department of Biological Sciences"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["University of Cape Town"]},{"key":"dc:type","label":"Dc Type","values":["Bachelor Thesis"]},{"key":"dc:type.qualificationlevel","label":"Dc Type Qualificationlevel","values":["Honours"]},{"key":"dc:type.qualificationname","label":"Dc Type Qualificationname","values":["BSc (Hons)"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language.iso","label":"Language (ISO)","values":["eng"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/11427/12721"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Includes bibliographical references."]},{"key":"dc:description.abstract","label":"Abstract","values":["Capensibufo rosei, a critically endangered bufonid found only within Table Mountain National Park, has shown a silent decline over recent decades, despite being found within a protected area with apparently pristine habitat. I estimated the first survival and recruitment rates for the species, using Capture-Mark-Recapture (CMR) methods, over a 7-year period, in order to identify demographic trends over time. I also used covariate models to test whether any observed trends in these demographic parameters were significantly related to variation in rainfall or drought-stress. I found some evidence for an extreme rainfall-induced life-history plasticity, with both survival and recruitment rates covarying closely with rainfall parameters. Although recruitment rate showed a positive relationship with rainfall, the relationship between survival rate and rainfall, specifically during the start of breeding, was negative, with breeding season rainfall explaining 94% of the variability in survival rate over time. I also found evidence to suggest that higher adult survival during poorer breeding rainfall years may be a natural population buffering mechanism to a highly variable microclimate, and that variable rainfall during the start of the breeding season may elicit a variable response in breeding investment by adults. Finally, I found evidence to suggest that the population is small, range-restricted and highly unstable, and that disturbances at the breeding site during good breeding years may cause the population to crash."]},{"key":"dc:title","label":"Title","values":["Searching for answers to the silent decline: first estimates of survival and recruitment for the critically endangered Rose's mountain toadlet, Capensibufo rosei"]}]}],"canonical_facts":{"dc:contributor.advisor":["Tolley, Krystal A","Altwegg, Res"],"dc:creator":["Becker, Francois Stephanus"],"dc:date.accessioned":["2015-05-04T07:13:49Z"],"dc:date.available":["2015-05-04T07:13:49Z"],"dc:date.issued":["2014"],"dc:description":["Includes bibliographical references."],"dc:description.abstract":["Capensibufo rosei, a critically endangered bufonid found only within Table Mountain National Park, has shown a silent decline over recent decades, despite being found within a protected area with apparently pristine habitat. I estimated the first survival and recruitment rates for the species, using Capture-Mark-Recapture (CMR) methods, over a 7-year period, in order to identify demographic trends over time. I also used covariate models to test whether any observed trends in these demographic parameters were significantly related to variation in rainfall or drought-stress. I found some evidence for an extreme rainfall-induced life-history plasticity, with both survival and recruitment rates covarying closely with rainfall parameters. Although recruitment rate showed a positive relationship with rainfall, the relationship between survival rate and rainfall, specifically during the start of breeding, was negative, with breeding season rainfall explaining 94% of the variability in survival rate over time. I also found evidence to suggest that higher adult survival during poorer breeding rainfall years may be a natural population buffering mechanism to a highly variable microclimate, and that variable rainfall during the start of the breeding season may elicit a variable response in breeding investment by adults. Finally, I found evidence to suggest that the population is small, range-restricted and highly unstable, and that disturbances at the breeding site during good breeding years may cause the population to crash."],"dc:identifier.uri":["http://hdl.handle.net/11427/12721"],"dc:language.iso":["eng"],"dc:publisher.department":["Department of Biological Sciences"],"dc:publisher.institution":["University of Cape Town"],"dc:title":["Searching for answers to the silent decline: first estimates of survival and recruitment for the critically endangered Rose's mountain toadlet, Capensibufo rosei"],"dc:type":["Bachelor Thesis"],"dc:type.qualificationlevel":["Honours"],"dc:type.qualificationname":["BSc (Hons)"]},"updated_at":"2026-07-22T22:23:39Z"}