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Reproductive behaviour and habitat use in the Blue-Eyed Black Lemur (Eulemur flavifrons, Gray, 1867) at the Sahamalaza-Iles Radama National Park, Madagascar.Volampeno, Maria S. N. January 2009 (has links)
The critically endangered blue-eyed black lemur (Eulemur flavifrons) is one the leaststudied
day active lemurs because of the recent rediscovery and limited distribution.
This thesis examined the habitat use, reproductive parameters and the population
viability of the blue-eyed black lemur population at Ankarafa Forest, Sahamalaza-Iles
Radama National Park, Madagascar. The main aim was to gather fundamental
information on the natural history of the blue-eyed black lemur and to propose
conservation approaches for both the species and its habitat. Data were collected over
14 month-period between 2006 and 2008. Six groups of the blue-eyed black lemur
were studied, four of which were collared and two uncollared.
Ankarafa Forest, the largest forest blocks of the Sahamalaza-Iles Radama
National Park, is dominated mainly by Mangifera indica, Garcinia pauciflora,
Sorindeia madagascariensis, Grangeria porosa, Bambou sp. and Mascarenhasia
arborescens species. The forest is vulnerable to degradation by both anthropogenic
activities and abiotic factors. The population density of the blue-eyed black lemur at
Akarafa Forest was estimated to be 97.3 individuals km-², with group size ranging
from 4 to 11 individuals. The home range use and day path length of the blue-eyed
black lemur varied seasonally. The lemur occupied a larger home range in the dry
season than in the wet season. The age of first reproduction in the blue-eyed black
lemurs is about 3 years. They bear offspring seasonally (late August-October), all
adult females in groups bred and females produce singletons offspring. Females were
dominant over males. The sex-ratio at birth was male-biased but not significantly
different from 1:1. Females were the primary caretakers of infants but group members
other than the mother also provided alloparental care. For the first 3 weeks of life,
infants were carried constantly on their mothers’ bellies. Infants developed
independent locomotion and fed on solid food by 10 weeks. Increased probability of
extinction, as shown by population viability models of the blue-eyed black lemur
population, is affected by various of their reproductive parameters. However, these do
not account for changes in their primary habitat forest. The latter is under increased
human pressure and continues to decline in area. Education awareness and community
involvement are required if the habitat and the blue-eyed black lemur are to survive.
Findings of this study serve not only important data to understand the life
history of the blue-eyed black lemur but also suggest conservation approaches for
both the species and its natural habitat. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2009.
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Evaluation of methods and approaches for surveying savanna invertebrates.Lovell, Saskie Joanne. January 2006 (has links)
The savanna is an important biome, which is under threat from land transformation, and it is therefore a
focus for conservation planning. Yet, the invertebrate fauna of this biome is poorly documented and
hence there is a need to provide baseline data for this component of biodiversity. This project aimed to
provide relevant information that can be used by conservation planners and ecologists, by recommending
a sampling strategy for the collection of specific taxa for savanna invertebrate surveys.
The effectiveness and efficiency of a sampling strategy using passive and active sampling methods was
assessed to provide recommendations for a multi-taxa approach to sampling invertebrates in a savanna
ecosystem. In the collection of data, volunteers assisted and they were evaluated in comparison with
experienced researchers to assess the effectiveness, efficiency and benefits of using volunteers to carry
out multi-taxa invertebrate surveys. In addition, cross-taxon congruency and congruency across
taxonomic levels were assessed between nine invertebrate taxa, to select potential surrogates to reduce
biodiversity survey costs for conservation planning.
Fieldwork was carried out in the Mkhuze Game Reserve (27.67°S:32.27°E, 400km2
), Phinda Private
Game Reserve (27.78°S:32.35°E, 140km2
) and False Bay Park (27.94°S:32.38°E, 25km2
) in north-eastern
Kwazulu-Natal, South Africa. Forty-three different sites were sampled between November 2002 and
March 2005 (summer months). Twenty of these sites were re-sampled across years and in different
months during the summer season, giving 77 sampling events. Fifty-four volunteers recruited by the
Earthwatch Institute assisted in the collection of data.
Lepidoptera, Hymenoptera (Apoidea), Diptera (Asilidae, Bombyliidae), Neuroptera, Odonata, Hemiptera
(Cicadellidae), Coleoptera (Cetoniinae, Scarabaeinae), Orthoptera, Blattodea, Isoptera, Araneae
(Araneidae, Thomisidae, Oxyopidae), Scorpionida, Myriapoda (Diplopoda, Chilopoda), Mollusca and
Annelida were sampled using four active searching methods (transects, tree beating, leaf litter and sweep
sampling) and two passive methods (pan traps and baited traps).
In its entirety, this project sampled 50 558 individuals from 797 invertebrate species and an extensive
database consisting of 33 257 records now exists. A standardised sampling protocol is described for the
effective sampling of multiple invertebrate taxa in a savanna biome and recommendations are made for
improving the efficacy and completeness of invertebrate surveys based on the application of species
accumulation models. Restrictive active searching methods (quadrats) were found to be more effective for
sampling epigaeic invertebrates and should be used in conjunction with leaf litter samples. Flying and
plant-dwelling invertebrates should be sampled using a range of sampling methods which include baited,
malaise and pan traps, active searching along transects and vacuum sampling. I suggest over 75% of the
Lovel/, s.1. - MSc. Thesis i ii
total estimated fauna to be a satisfactory and realistic level of inventory completeness for making valid
comparisons between regions and across sites.
Volunteers sampled lower rates of species accumulation, species richness and unique species when using
timed, active search methods. Nevertheless, volunteers and researchers were shown to perform equally
well when using un-timed, active searching methods. Previous experience or knowledge of scientific
method was beneficial when researchers assessed the perceived usefulness of volunteers to researchers for
carrying out fieldwork. The project experience raised the volunteers' environmental awareness,
knowledge about biodiversity, invertebrates and conservation research, and enabled volunteers to
participate in or design locally relevant conservation based projects on their return home.
Cross-taxon congruencies were observed. However, relationships were weak and potential surrogates
could not be selected. The use of higher taxonomic levels to represent species shows good potential as a
surrogate but only in species-poor genera or families. The use of species density to determine congruency
and select surrogates is likely to produce different results to those produced by community similarity.
Furthermore, when selecting surrogates from congruency assessments an optimal p-value greater than
0.75 should be required. Below this value, the relationship is likely to be weak and if used as a surrogate
misinterpretation may occur. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
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Feeding behavior of loggerhead and leatherback sea turtles:a study to better understand longline bycatchUnknown Date (has links)
Two species of sea turtle, loggerheads (Caretta caretta) and leatherbacks (Dermochelys
coriacea) are caught frequently as bycatch in longline fisheries. These fisheries use
hooks baited with fish or squid. Yet, leatherbacks feed on gelatinous prey while
loggerheads are carnivores. I investigated the responses of these two species to bait
odors in controlled laboratory experiments to better understand their feeding behavior
and why they interact with longlines. Both species initiated feeding behavior in the
presence of squid bait odors and just C. caretta showed feeding behavior with sardine
odors; neither responded to mackerel odors. The turtles are hooked differently on
longlines. Loggerheads are usually hooked in the mouth while leatherbacks are usually
hooked in the shoulder or flippers. Comparisons of prey attack behavior and accuracy in
apprehending a stimulus in the presence of waterborne food odors identified speciesspecific differences that may predispose the turtles to particular kinds of hooking. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
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Conservation of the great white pelican (Pelecanus onocrotalus) and the pink-backed pelican (P. rufescens) in south eastern Africa.January 2006 (has links)
Of the seven pelican species found world wide, only the Great White Pelican (Pelecanus onocrotalus) and the Pink-backed Pelican (P. rufescens) are found in Africa. The KwaZulu-Natal province of South Africa supports only one breeding site for each of these species, and both sites represent the southern most breeding colonies for the two species in the eastern region of Africa. These nesting sites fall within the Greater St Lucia Wetland Park, and are afforded a degree of protection, but the same is not true for their foraging and dispersal ranges, and this is a cause for concern. Considerable amounts of data have been collected relating to the status, distribution and breeding efforts of these two species in north eastern KwaZulu-Natal. These data have been collected in a variety of ways by a large number of people. Part of this work represents an attempt to collate and summarise these data to produce an estimation of the status, distribution and breeding success of these species, and to evaluate any trends in their demography. For this south eastern region of Africa I estimated the population for the Great White Pelican to range between 6000 and 9000 individuals, and the Pink-backed Pelican to range between 600 and 900 individuals. Pelicans are highly mobile birds, and this allows them to move considerable distances when they forage, disperse or migrate. They are also long-lived birds with few natural predators. The two pelican species in south eastern Africa have been poorly studied and little is known about their movements, population dynamics and causes of mortality. Habitat change poses a potential threat to pelicans in north eastern KwaZulu-Natal, and habitat loss could drive these species out this region to areas north of South Africa. Much of this north eastern region of KwaZulu-Natal is under threat, mainly through the actions of man. Many areas are naturally unsuitable for pelican foraging, while others are vital to the survival of both species. This study includes an attempt to assess the movements of these two species in south eastern Africa, and to assess the relative importance and condition of the potential pelican habitat in the north eastern KwaZulu-Natal region, focusing particularly on Lake St Lucia and the Pongolo River floodplain. All this is necessary to produce a baseline from which long term predictions of potential pelican species survival can be made. In the absence of documented life tables and environmental variability data, a range of parameters was modelled to generate population viability analyses to simulate possible scenarios. These extinction models show the outcomes of both the deterministic and the stochastic processes. An attempt was also made to identify the factors that impact most severely on the persistence of these two species. The models were most sensitive to variation in survivorship in the first year of life and to the frequency of catastrophes. Changes in these parameters had the greatest effect on extinction risk. In January 2004 Lake St Lucia was reduced to a fraction of its normal capacity as a result of a severe drought in this region of KwaZulu-Natal. After rains in the area the lake level rose and then fluctuated considerably over the next 24 months. During this time the mouth of the estuary into the sea was closed. Great White Pelican numbers and lake levels were monitored throughout this period. This part of the study relates the changes in population numbers to the lake conditions, and highlights the importance of the lake to this avian species. It uses lake levels as a proxy for the conditions of wetlands in the Lake St Lucia region. It also addresses the implications of these relationships to the management strategy of the lake and the conservation of some avifauna. To identify conservation concerns for the Great White and Pink-backed Pelicans it was necessary to generate these baseline estimations. Although much of this information is uncertain for these two species, an attempt has been made here to predict the persistence of these species in north eastern KwaZulu-Natal and to highlight the conservation issues related to their future. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006
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Sharing the range: the challenges and opportunities for sustainable ranching and habitat conservation in the municipal district of Pincher CreekSadilkova, Regina Maria 11 1900 (has links)
The broad scope and intent of this thesis is to contribute to the body of research and
writing about the loss of agricultural land due to development and the transformation of rural
agricultural communities. At the more specific level, through interviews and secondary research,
this thesis considers municipal land use planning in Alberta under the revised 1995 Municipal
Government Act in the Municipal District (MD) of Pincher Creek No. 9, where cattle ranching,
wildlife, and now, acreages vie for land resources. The critical questions addressed are:
What are the conflicts between ranching and habitat conservation, and
conversely, what opportunities do they share?
What role can and does a municipality play in promoting sustainable
ranching and conservation through its land use policy and jurisdiction?
Set in southwest corner of Alberta, the MD of Pincher Creek is endowed with a
remarkable history of ranching, ample resource wealth, and a unique climate and topography
that supports a spectacular, rich, diverse ecosystem. Within the past few years, private
agricultural land near Waterton Lakes National Park and the Castle River wilderness in the MD
has come under speculative and development pressure predominantly for country residences,
often retirement homes, and for tourism interests. Recent Municipal Act amendments have
delegated substantially more land use control to rural municipalities, as a result the MD of
Pincher Creek has more authority to make decisions that shape its future community profile, to
mediate between competing land use interests, and to impact local ranching and habitat.
The thesis analysis explores how the best practices of ranching or "sustainable ranching"
can help to conserve and enhance habitat and how ranchers' attitudes can evolve to be more
tolerant of wildlife. This thesis also explores and supports the efforts of a budding local land
trust, SALTS, which plans to protect local agricultural land and habitat through conservation
easements. Finally, the thesis concludes by envisioning ways the MD government can encourage
habitat preservation, conservation easements, sustainable and economically viable ranching, as
well as the control and direction of country residential development, all with a view to ensuring
that future economic development opportunities remain available for local residents.
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An investigation to determine the critical habitat requirements of the breeding Blue Swallow Hirundo atrocaerulea Sundevall.Wakelin, James. January 2006 (has links)
This study investigated the critical habitat requirements of breeding Blue
Swallows Hirundo atrocaerulea Sundevall, in KwaZulu-Natal, South Africa.
Blue Swallows, as a 'flagship species' of the KwaZulu-Natal endemic Mistbelt
Grassland, were tagged and radio-tracked to obtain positional data to determine
their habitat use while breeding. This information was correlated to the type
and nature of the habitat used and to the nature of the land cover to determine
the likely impact of habitat transformation and fragmentation on breeding Blue
Swallows. Insect type and abundance was assessed in five surrounding habitat
types using Malaise insect traps and the findings correlated to Blue Swallow
habitat usage. Data on environmental variables were collected using HOBO®
sensors and the findings related to insect type and abundance within each
habitat type. A comparative investigation was undertaken using temperature
and humidity data obtained below-ground at a Blue Swallow nest site and
compared to temperature and humidity findings from above-ground.
Preliminary investigations were also made into the breeding system used by the
Blue Swallow using unique wing markings to estimate the number of individuals
involved at a single active nest.
Overall, wetland and grassland were first choice habitats a function of the
increased individual insect mass in these habitats. Tea plantations were the
next most important habitat type and timber plantations were avoided.
Furthermore, it was shown that the Blue Swallow is a species that favours
ecotones as preferential forage zones, particularly the ecotone between wetland
and grassland. Malaise insect traps were effective in gathering suitable insect
samples for analysis, revealing that significant differences occur in insect order,
number and mass between habitat types. The most significant finding is that
average insect mass per order, which was correlated closely to habitat type,
matches the order of positive habitat type selection by the Blue Swallow. These
findings were statistically significant and it is suggested that this correlation is the
main reason behind the habitat selection by Blue Swallows. This study found a
clear indication that insect numbers and mass, in grassland and wetland,
increase with an increase in temperature and decrease with a decrease in
average temperature. Clear trends were obvious during long periods of either
cold or dry weather which .negatively influenced insect abundance and
potentially, in turn, Blue Swallow well-being. The underground cavity used as
the nesting site by Blue Swallows, experiences a greatly moderated climate in
terms of the range of environmental factors compared with those experienced
above-ground. This climate moderation is thought to be a clear advantage for
the well-being of the Blue Swallow eggs and nestlings.
Through the use of radio-tracking, visual markers and video footage it was clear
that Blue Swallows breed with a number of adult birds at one nest. The
recorded average sex ratio was 1(; : 3<;2, however, the need remains to
elucidate the co-operative breeding system used by the Blue Swallow.
In conclusion, the findings of this work present recommendations and
suggestions on habitat management, offer insight into future research
opportunities, and suggest strong conservation action for the species. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2006.
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The effect of land use on the species composition of amphibians in North Eastern KwaZulu-Natal.Russell, Charlene. January 2010 (has links)
Global declines in amphibian species have directed research towards investigating why this is happening. One of the major causes of these declines is the fragmentation and loss of habitat. This study examined the effect of land use on the species composition of frogs within North Eastern KwaZulu-Natal, and the use of buffer zones to facilitate the protection of these species. Three land use types were investigated: sugar cane (Saccharum officinarum), gum (Eucalyptus sp.) plantations and conservation areas. The average number of frog species differed between areas: conservation 13.2 ± 6.6; plantations 3.8 ± 1.3; and sugar cane 2.8 ± 1.4. Sugar and gum plantation were found to be lacking the wetland and grassland/woodland habitats. In addition to this, the frog species that were not present on these land use types were those that are totally dependent on water as well as those that are not dependent on a water source. Two species were highlighted as possible indicator species of land use: Amietophrynus gutturalis and Hyperolius marmoratus.
To mitigate the effect of these land use types, the use of buffer zones was explored in a desktop study. A range of buffer zones were applied to wetlands in a sample study area, using a range of distances including the distances of 290 m and 159 m recommended by Semlitsch and Bodie (2003), and the recommended distances for wetlands in South Africa of 10-20 m. The application of a 290 m and 159 m buffer zone on a conglomerate of wetlands connected by a 100m buffer was the most feasible as it incorporated a percentage of the total study (6.4% and 4.3%) area similar to the percentage occupied by the recommended 20m buffer zone (5.5%) around all wetlands, and still incorporated the range under protection put forward by Semlitsch and Bodie (2003). Management implications of these findings are discussed. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.
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Ecology and management of bushland in Australian citiesStenhouse, Renae N. January 2005 (has links)
[Truncated abstract] Native vegetation (bushland) in urban areas remains in small, isolated patches embedded within a matrix of human-dominated land uses. Bushlands in urban areas have high biodiversity conservation and social values, and there has been a local-level movement towards protecting and managing urban bushlands in Australia. This thesis aims to test principles, theories and concepts relating to the ecology and management of bushland fragments in Australian cities ... A commonly used qualitative scale was compared with an ecologically based, quantitative technique developed in the research. The qualitative scale was found to be a reliable proxy for assessing vegetation condition, while also being more user-friendly for community groups and other bushland managers. The human-caused disturbances and weed cover in urban bushlands indicate a need for management intervention. Local government has an important role in local biodiversity management, yet there has been little research on this topic ... Positive partnerships developed where local governments have taken a ‘contract model’ approach to volunteer coordination, have a number of expectations of volunteer groups, and provide the groups with relatively high level of assistance. Also important is a local government that supports, respects, trusts and communicates with the community group, and recognises volunteers’ skills, knowledge and contributions. With increased resources allocated to local government bushland management and conservation, and coordination with community groups, the full potential of local bushland management would be realised.
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Sharing the range: the challenges and opportunities for sustainable ranching and habitat conservation in the municipal district of Pincher CreekSadilkova, Regina Maria 11 1900 (has links)
The broad scope and intent of this thesis is to contribute to the body of research and
writing about the loss of agricultural land due to development and the transformation of rural
agricultural communities. At the more specific level, through interviews and secondary research,
this thesis considers municipal land use planning in Alberta under the revised 1995 Municipal
Government Act in the Municipal District (MD) of Pincher Creek No. 9, where cattle ranching,
wildlife, and now, acreages vie for land resources. The critical questions addressed are:
What are the conflicts between ranching and habitat conservation, and
conversely, what opportunities do they share?
What role can and does a municipality play in promoting sustainable
ranching and conservation through its land use policy and jurisdiction?
Set in southwest corner of Alberta, the MD of Pincher Creek is endowed with a
remarkable history of ranching, ample resource wealth, and a unique climate and topography
that supports a spectacular, rich, diverse ecosystem. Within the past few years, private
agricultural land near Waterton Lakes National Park and the Castle River wilderness in the MD
has come under speculative and development pressure predominantly for country residences,
often retirement homes, and for tourism interests. Recent Municipal Act amendments have
delegated substantially more land use control to rural municipalities, as a result the MD of
Pincher Creek has more authority to make decisions that shape its future community profile, to
mediate between competing land use interests, and to impact local ranching and habitat.
The thesis analysis explores how the best practices of ranching or "sustainable ranching"
can help to conserve and enhance habitat and how ranchers' attitudes can evolve to be more
tolerant of wildlife. This thesis also explores and supports the efforts of a budding local land
trust, SALTS, which plans to protect local agricultural land and habitat through conservation
easements. Finally, the thesis concludes by envisioning ways the MD government can encourage
habitat preservation, conservation easements, sustainable and economically viable ranching, as
well as the control and direction of country residential development, all with a view to ensuring
that future economic development opportunities remain available for local residents. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
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Conservation in human-influenced areas : epigaeic arthropods in the Cape Floristic Region LowlandsBoonzaaier, Carmen 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: The conservation of biodiversity is becoming increasingly challenging as habitats are
disturbed, fragmented or destroyed. Although nature reserves now cover more than 10 %
of the earths’ surface it has become clear that more will have to be done to ensure the
long-term survival of species. Therefore, focus is increasingly shifting towards
conserving biodiversity in natural and semi-natural remnants in human-influenced areas.
This study aimed to determine the contribution of remnants in human-influenced areas to
the conservation of biodiversity in the Cape Floristic Region (CFR) lowlands, using
ground-dwelling arthropods, specifically ants, as the focal taxon. Initially, base-line
information of arthropods and in particular ants was obtained. Sampling arthropods
generally involves a large sample effort. Therefore maximizing sampling effort for ants
in the CFR was investigated by trapping ground-dwelling ants at a single locality.
Doubling the number of grids of pitfall traps was found to be more effective in trapping a
greater number of species than doubling the duration of sampling. Therefore increasing
spatial sampling intensity rather than sampling duration maximizes sample effort for CFR
ants. Also, the seasonal changes of ground-dwelling arthropods, including ants, were
determined by sampling four times during the year at a single locality. Overall arthropod
abundance was found to peak in summer while dropping to a minimum in winter. This
pattern was mirrored by that of the ants, indicating that ant results have a broader
relevance than to ants only. The ground-dwelling fauna was dominated by ants
emphasizing their importance in the CFR lowlands, and demonstrating that ants are an
appropriate flagship taxon for epigaeic arthropod diversity in the CFR. Finally the
contribution of remnants in human-influenced areas to the conservation of the CFR was
investigated. A nested hierarchical approach was used, where five localities were selected
across the CFR, each containing one reserve site and one site with natural remnants. Ants
were sampled, along with environmental variables, namely weather, vegetation and soil.
Overall, remnants were found to support similar ant assemblages to those of reserves.
However for individual localities some remnants were significantly different to their
reserve counterparts. Differences in ant assemblages were found to be greater between
localities than between reserves and remnants. The relatively high heterogeneity of ants found in this study emphasizes the conservation significance of invertebrates along with
that of plants in the CFR. Remnants clearly show the potential to conserve ant
assemblages, however correct management is needed for these areas to maximize their
potential. Disturbances such as the presence of the invasive Argentine ant and increasing
soil nutrients by fertilization, pose a distinct threat to the ability of remnants to conserve
ant assemblages. This study has shown that remnants currently support ant assemblages
representative of those present in the CFR today. Therefore, some remnant patches of
habitat in agricultural areas currently do contribute highly to the conservation of a
functional important taxon in this global biodiversity hotspot, and if managed correctly,
may continue to do so in the future. / AFRIKAANSE OPSOMMING: Die vernietiging en fragmentering van habitatte maak die bewaring van biodiversiteit al
hoe meer van ‘n uitdaging. Alhoewel natuur reservate reeds meer as 10 % van die aarde
se oppervlak beslaan is dit duidelik dat meer gedoen sal moet word vir die lang-termyn
voortbestaan van spesies. Dus word die fokus van biodiversiteit-bewaring toenemend
gerig op bewaring van natuurlike en semi-natuurlike fragmente in menslik-beinvloede
gebiede. Die doel van hierdie studie was om te bepaal wat die bydrae van fragmente van
natuurlike veld in menslik-beinvloede gebiede is tot die bewaring van die streek. Dit is
gedoen deur van grond-lewende geleedpotiges en spesifiek, miere in die Kaapse floraryk
(CFR) gebruik te maak. Aanvanklik is kennis ingewin oor die geleedpotiges en spesifiek
miere in die omgewing. Omdat die versameling van geleedpotige diere gewoonlik baie
moeite vereis is ‘n maksimum steekproef gedoen by ‘n enkele lokaliteit. Daar is gevind
dat ‘n verdubbling van die aantal ruitsteekproefnemings met vanggate meer effektief is
om miere te vang as ‘n verdubbling in die tydperiode wat vanggate oop is. Dus, is ‘n hoër
ruimtelike steekproef intensiteit meer effektief in vergelyking met ‘n langer tydsduur vir
miere in die CFR. Die seisoenale veranderinge van grond-lewende geleedpotiges, sowel
as miere, was ook bepaal. Dit was gedoen deur vier seisoenale steekproewe te doen by ‘n
enkele lokaliteit. Die totale geleedpotige-talrykheid was die meeste gedurende die somer
en die minste in die winter. Die miertalrykheid het ook hierdie patroon weerspieël. Dit
dui daarop dat veranderinge in mier versamelings van breër belang is vir alle grondlewende
geleedpotiges. Miere was die dominante grond-lewende geleedpotiges en
beklemtoon die belangrikheid van miere in die CFR, sowel as hulle toepaslikheid as
vlagskip taksa vir grond-lewende geleedpotige diversiteit in die CFR. Laastens was die
bydrae van gefragmenteerde natuurlike veld in menslik–beinvloede gebiede tot die
bewaring van die CFR ondersoek. ’n Krimpende/ genestelde hiërargies benadering is
gebruik in vyf geselekteerde lokaliteite, elk het bestaan uit ‘n area in ‘n natuur reservaat
en ‘n area in ‘n naasliggende fragment. Miere was versamel saam met ‘n verskeidenheid
omgewings veranderlike, naamlik weer, plantegroei en grond. In die algemeen is gevind
dat fragmente en reservate gelyksoortige mier versamelings het. Daar was wel gevind dat
party fragmente aansienlik verskillend was van die reservaat teenstuk. Verskille in mier versamelings tussen lokaliteite was groter as verskille tussen reservate en fragmente. Die
relatief hoë heterogeniteit van miere beklemtoon die bewaringsbelang van invertebrate
saam met dié van plante in die CFR. Dit is duidelik dat fragmente wel ‘n potensiale
bydrae kan maak om die mier versamelinge te bewaar, maar gepaste bestuur is nodig om
hierdie potentiaal te maksimaliseer. Versteurings soos die teenwoordigheid van die
indringer Argentynse mier en toenemende grondvoedingstofkonsentrasie as gevolg van
bemesting is ‘n groot bedreiging tot die vermoë van fragmente om mier versamelings te
bewaar. Hierdie studie wys dat mier versamelings in gefragmenterde areas
verteenwordigend is van die algemene mier versamlings wat op die oomblik in die CFR
is. Dus lewer party fragmente in landbou gebiede op die oomblik ‘n wesenlike bydrae tot
die bewaring van ‘n funksioneel belangrike takson in hierdie globale
biodiversiteitsbrandpunt en die bydra sal volhoubaar wees met korekte bestuur.
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