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Comparing the Use of Abundance and Consistent Occupancy Measures to Predict Local Species PersistenceGrouios, Christopher 03 January 2011 (has links)
I compared the utility of two continuous time-series data measures for applied conservation biology by investigating how well each could predict future local persistence of a diverse set of bird species. I used 37 years of data from the North American Breeding Bird Survey to
calculate abundance from yearly point-counts and permanence (i.e., consistent occupancy over time) from yearly presence-absence data in the early portion of the study period, then used the later portion of data to empirically evaluate how well each measure predicted persistence two decades into the future. I found that permanence could only match the ability of abundance to accurately predict local species persistence if multiple within-year repeated observations
contributed to its calculation. Neither measure was effective at predicting persistence for regionally rarer species. I suggest the yearly and within-year repeated collection of abundance estimating data for use in applied conservation biology to best ensure biodiversity persistence.
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Comparing the Use of Abundance and Consistent Occupancy Measures to Predict Local Species PersistenceGrouios, Christopher 03 January 2011 (has links)
I compared the utility of two continuous time-series data measures for applied conservation biology by investigating how well each could predict future local persistence of a diverse set of bird species. I used 37 years of data from the North American Breeding Bird Survey to
calculate abundance from yearly point-counts and permanence (i.e., consistent occupancy over time) from yearly presence-absence data in the early portion of the study period, then used the later portion of data to empirically evaluate how well each measure predicted persistence two decades into the future. I found that permanence could only match the ability of abundance to accurately predict local species persistence if multiple within-year repeated observations
contributed to its calculation. Neither measure was effective at predicting persistence for regionally rarer species. I suggest the yearly and within-year repeated collection of abundance estimating data for use in applied conservation biology to best ensure biodiversity persistence.
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Identification of intertidal marine reserves – using habitat types to identify areas of high conservation valueSimon Banks Unknown Date (has links)
The goal of biodiversity conservation has been described as the conservation of diversity at three levels: ecosystem, species and genetic diversity. Developing a representative system of marine protected areas is considered an effective way to achieve this goal in the marine environment. The growing concern associated with threats to the marine environment has resulted in an increased demand for marine reserves (i.e. no-take areas) that conserve representative and adequate examples of biodiversity. Often, the decisions about where to locate reserves must be made in the absence of detailed information on the patterns of distribution of the biota. Alternative approaches are required that include defining habitats as surrogates for biodiversity. The development of biodiversity surrogates at fine-scales (i.e. habitats) will have an increasingly important role in the identification of sites that will contribute to a representative system of marine protected areas. This is because it will increase the likelihood that the system will adequately achieve biodiversity objectives by ensuring protection of a greater range of habitats and species. Surrogate measures of biodiversity enable decisions about where to locate marine reserves to be made more reliably in the absence of detailed data on the distribution of species. There is concern, however, about the reliability of surrogate measures to represent biotic diversity and the use of such measures in the design of marine reserve systems. Currently, surrogate measures are most often based on broad-scale (100s to 1000s of kilometres) bioregional frameworks that define general categories (sandy beach, rocky shore) for intertidal systems. These broad-scale categories are inadequate when making decisions about conservation priorities at the local level (10s to 100s of metres). This study provides an explanation of an intertidal shoreline habitat surrogate (i.e. shoreline types) used to describe 24,216 kilometres of Queensland’s coastline. The protective status of shoreline types was evaluated to assist with designing a representative system of intertidal marine protected areas. The shoreline types derived using physical properties of the shoreline were used as a surrogate for intertidal biodiversity to assist with the identification of sites for inclusion in a candidate system of intertidal marine reserves for 17,463 kilometres of the mainland coast of Queensland, Australia. This represents the first systematic approach, on essentially one-dimensional data, using fine-scale (10s to 100s of metres) intertidal habitats to identify a system of marine reserves for such a large length of coast. A range of solutions would provide for the protection of a representative example of shoreline types in Queensland. Shoreline types were used as a surrogate for intertidal biodiversity (i.e. habitats, microhabitats) to assist with the identification of sites to be included in a representative system of marine reserves in south east Queensland. The use of local-scale shoreline types increased the likelihood that sites identified for conservation achieved representation goals for the mosaic of habitats and microhabitats, and therefore the associated biodiversity present on rocky shores, than that provided by the existing marine reserve protection in south east Queensland. These results indicate that using broad-scale surrogate measures (rocky shore, sandy beach) for biodiversity (habitats, microhabitats and species) are likely to result in poor representation of fine-scale habitats and microhabitats, and therefore intertidal assemblages in marine reserves. When additional fine-scale data were added to reserve selection the summed irreplaceability of 24% (for spatial extent of habitats), and 29% (for presence/absence of microhabitats) of rocky shore sites increased above zero, where a value close to one means a site is necessary, for inclusion in a reserve system, to meet conservation targets. The use of finer-scale physical data to support marine reserve design is more likely to result in the selection of reserves that achieve representation at habitat and microhabitat levels, increasing the likelihood that conservation goals will be achieved. The design and planning of marine and terrestrial protected areas systems should not be undertaken independently of each other because it is likely to lead to inadequate representation of intertidal habitats in either system. The development of reserve systems specially designed to protect intertidal habitats should be integrated into the design of terrestrial and marine protected area systems. Marine reserve networks are a necessary and effective tool for conserving marine biodiversity. They also have an important role in the governance of oceans and the sustainable management of marine resources. The translation of marine reserve network theory into practice is a challenge for conservation practitioners. Barriers to implementing marine reserves include varying levels of political will and agency support and leadership, poorly coordinated marine conservation policy, inconsistencies with the use of legislation, polarised views and opposition from some stakeholders, and difficulties with defining and mapping conservation features. The future success of marine reserve network implementation will become increasingly dependent on: increasing political commitment and agency leadership to remove conflicts within and between government agencies involved in site identification and selection; greater involvement and collaboration with stakeholders; and the provision of resources to define and map conservation features. Key elements of translating marine reserve theory into implementation of a network of marine reserves are discussed based on approaches used successfully in New Zealand and New South Wales (Australia).
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The mesofilter concept and biodiversity conservation in Afro-montane grasslandsCrous, Casparus Johannes 03 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2013. / ENGLISH ABSTRACT: Conservation planners use many traditional biodiversity conservation tools to help alleviate
the global biodiversity crisis. However, ongoing biodiversity loss has stimulated the
development of new and improved methods for conserving biodiversity. One such new
conservation tool is the mesofilter approach. Mesofilters are biotic or abiotic ecosystem
elements which are critical to the well-being of many species, and therefore could help to
explain spatial heterogeneity in species across a landscape. It is also complementary to more
traditionally used concepts such as coarse- and fine-filter conservation concepts. Applying the
mesofilter approach in protected area, conservancy, or land-sparing design and management,
could optimise biodiversity conservation in a rapidly developing world. For example, the
timber industry has been pro-active in its approach to lessen biodiversity loss, by optimising
design and management of the plantation matrix through ecological networks. Here, I explore
the use of mesofilters within highly threatened remnant Afro-montane grasslands in
KwaZulu-Natal, South Africa, to optimise biodiversity conservation planning for such
landscapes. As per anecdotal evidence, I used rockiness in the landscape as a possible driver
of species richness and species assemblage variability at the meso-scale, using a multi-taxon
and multi-trophic approach. In this montane landscape, I also examined the effect of elevation
on spatial heterogeneity of taxa. I further examined the functional responses of taxa to
rockiness in the landscape. Rockiness in the landscape significantly influenced the species
richness and assemblage structure of three key grassland taxa: flora, butterflies, and
grasshoppers. I showed that for plants, this response was due to growth forms such as
geophytes and perennial grasses that were more closely associated with rockiness, and
therefore the main contributors to observed differences in the dispersion patterns of flora.
Grasshoppers were not necessarily responding to higher rock exposure per se, but rather
towards the environmental conditions created by rockiness within the landscape, such as
lower vegetation density. For butterflies, certain behavioural traits, such as resting, territorial
behaviour and/or mate-locating behaviour, were more typical in areas of higher rock
exposure. This suggested that rocks are a definite habitat resource to certain butterflies.
Overall, this finding where an abiotic surrogate is representative of key taxa in an ecosystem
is interesting, as cross-taxon surrogacy has been shown to be stronger than surrogates based
on environmental data. Furthermore, taxa responded functionally to rockiness in the
landscape. This thesis therefore supports the idea that environmental surrogates are indeed
useful for biodiversity conservation planning. Furthermore, ecosystems can potentially have many attributes or features that would be of conservation interest, and delineating a set of
mesofilters is a useful way of expressing particular attributes to be used in wildlife
conservation evaluation. The concept of the mesofilter as a practical biodiversity conservation
tool is therefore validated here. I also argue the importance of habitat heterogeneity for
biodiversity conservation planning in this montane grassland landscape. The potential for
optimising the design of landscape configurations such as ecological networks, through
information obtained from the mesofilter, is emphasised. We can safely add another tool in
the biodiversity conservation toolbox of this Afro-montane grassland ecosystem. / AFRIKAANSE OPSOMMING: Bewaringbeplanners gebruik tans baie tradisionele biodiversiteit-bewarings metodes om die
huidige biodiversiteits krisis te help verlig. Tog, die huidige voortdurende verliese in
biodiversiteit wêreldwyd, vra na nuwer en verbeterde metodes van biodiversiteit-bewaring.
Een so ‘n nuwe bewaring metode, is die mesofilter. Mesofilters is biotiese of abiotiese
ekosisteem elemente wat kritiek is tot die welstand van spesies, en daarom veral waardevol is
om variasie in spesies verspreiding in ‘n landskap te help verduidelik. Daarby is die
mesofilter konsep ook komplementêr tot meer tradisioneel gebruike bewaringskonsepte, soos
fyn-filter en breë-filter konsepte. Deur die mesofilter benadering toe te pas in die ontwerp en
bestuur van beskermde areas, bewaareas, of land-spaar initiatiewe, kan ons biodiversiteitbewaring
in ‘n vining ontwikkelende wêreld optimaliseer. Byvoorbeeld, die bosbou industrie
is pro-aktief in hul benadering om biodiversiteit verliese te verminder, deur optimalisering
van die ontwerp en bestuur van ekologiese netwerke in die plantasiematriks. In hierdie tesis,
ondersoek ek die gebruik van mesofilters in hoogs bedreigde oorblyfels Afrikaberg grasvelde
in KwaZulu-Natal, Suid-Afrika, om die bewaringsbeplanning van dié gebiede te optimaliseer.
Vanaf anekdotiese bewyse, het ek spesifiek gebruik gemaak van klipperigheid in die landskap
as ‘n moontlike drywer van spesies-rykheid en spesies-samestelling variasie by ‘n meso-skaal,
deur ‘n multi-takson en multi-trofiese benadering. In hierdie berglandskap, het ek ook die
effek van hoogte bo seevlak op ruimtelike verspreiding van taksa bestudeer. Verder het ek
ook gekyk na die funksionele reaksie van taksa tot klipperigheid in die landskap.
Klipperigheid in die landskap het ‘n beduidende invloed gehad op spesies-rykheid en spesiessamestelling
van drie sleutel grasveld taksa: plante, skoenlappers, en springkane. Ek wys dat
vir plante, hierdie reaksie as gevolg was van spesifieke plantgroeivorme, soos bolplante en
meerjarige grasse, se noue verband met klipperigheid, en daarom, dat hierdie groepe die hoof
bydraers is tot gesiene variasie in plantspesies verspreiding in die landskap. Vir springkane,
was hierdie reaksie nie noodwendig omdat hulle die klippe self gebruik het nie, maar meer as
gevolg van die omgewingskondisies geskep deur verhoogde klipperigheid in die landskap,
soos laer plantegroei digtheid. Vir skoenlappers, was hierdie reaksie tot klippe as gevolg van
sekere gedragskaraktereienskappe, soos rus op klippe, gebied beskerming en/of paarmaat
soektog, wat tipies meer gesien was in klipperige omgewings. Dit dui daarop dat klippe ‘n
definitiewe habitat hulpbron is vir sekere skoenlappers. Oor die algemeen is hierdie
bevinding, waar abiotiese surrogate verteenwoordig is van drie sleutel taksa in ‘n ekosisteem,
baie interessant, siende dat tussen-takson surrogate soms gesien word as sterker as surrogate gebaseer op omgewingsdata. Verder, taksa het funksioneel gereageer teenoor die klippe in die
landskap. Hierdie tesis ondersteun dus die idee dat omgewingssurrogate wel nuttig is vir
biodiversiteit-bewaring beplanning. Ekosisteme mag vele potensiele elemente van bewarings
belang bevat, maar om sulke elemente as ‘n stel mesofilters te klassifiseer, is ‘n nuttige
manier om spesifieke elemente te gebruik in natuurbewarings evaluasie initiatiewe. Gevolglik
word die konsep van die mesofilter as ‘n praktiese biodiversiteit-bewaring gereedskapstuk
hier bevestig. Ek beredeneer ook die belangrikheid van habitat heterogeniteit vir
biodiversiteit-bewaring van hierdie berggrasveld landskap. Die potensiaal vir optimalisering
van ontwerp en bestuur van landskap konfigurasies, soos ekologiese netwerke, word
beklemtoon. Ons kan met veiligheid nog ‘n gereedskapstuk plaas in die biodiversiteitbewarings
gereedskapkis van hierdie Afrikaberg grasveld ekosisteem.
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