Spelling suggestions: "subject:"baranes (birds)exmouth africa."" "subject:"baranes (birds)exmouth affrica.""
1 |
Investigation of RAPDs and microsatellites for use in South African cranes.King, Heather Anne. 29 November 2013 (has links)
The three South African crane species, namely, the Wattled Crane (Bugeranus
carunculatus), the Blue Crane (Anthropoides paradisea) and the Grey Crowned Crane
(Balearica regulorum regulorum) are all threatened. South African legislation protects the
cranes, however eggs and/or fledglings are sometimes illegally collected from the wild. These
are then sold, often by registered breeders, who falsely claim them as the offspring of their
captive breeding pair. DNA fingerprinting is one method to detect this crime.
Fifteen RAPD primers were screened for polymorphism in the three species. Seven
primers produced polymorphic profiles in the Blue Crane and eight each in the Grey Crowned
Crane and Wattled Crane, with an average of 14.57, 12.38 and 5.88 scorable loci per primer,
respectively. The Band Sharing Coefficient for unrelated individuals was found to be 0.665,
0.745 and 0.736 for the Blue, Grey Crowned and Wattled Crane respectively.
Five microsatellite primers, originally developed for use in Whooping Cranes (Grus
american), had previously been shown to be polymorphic in the Wattled Crane. This was also
the case in this study with an average of 3.6 alleles per primer. Although all primers cross
amplified, only a single primer each showed polymorphism in the Blue Crane (showing 6
alleles) and the Grey Crowned Crane (showing 5 alleles).
The RAPDs were found to be irreproducible, show high numbers of novel bands and
had parent: offspring BSC values that were not significantly higher than those of unrelated
individuals. Statistics showed that, in the Blue Crane, the probability that misassigned parents
would be detected was low whilst there was an almost certainty that true parents would be
incorrectly excluded.
The five microsatellite primers examined gave exclusionary powers of 0.869 and 0.641
where one or two parents were unknown in the Wattled Crane. The exclusionary powers for
the Blue Crane and Grey Crowned Crane calculated at only one locus were much lower. It was concluded that RAPDs were totally inappropriate for parentage analyses,
however, microsatellites are a suitable technique and recommendations are made that other microsatellites, developed for other species of crane, should be examined for their potential in
this respect. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2004.
|
2 |
Modelling risk of Blue Crane (Anthropoides paradiseus) collision with power lines in the Overberg regionKotoane, Mapule 12 1900 (has links)
Thesis (MA)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: This study addresses the problem of Blue Crane (Anthropoides paradiseus) collisions with
power lines in the Overberg region, home to approximately 50% of South Africa's national
bird's global population. The low visibility of power lines against the landscape is considered
to be the major cause of collisions. These claim at least 20 birds annually, which is a
considerable loss to a vulnerable species.
For this study, expert knowledge of the Blue Cranes' biology, general behaviour and use of
its habitat were compiled. These were then translated into rules that were integrated into a
Geographic Information System (GIS) to establish a predictive model, which attempts to
identify and quantify risk power lines that Blue Cranes are most likely to collide with. The
criteria that were considered included landscape proximity of power lines to water bodies arid
congregation sites, land cover, power lines orientation in relation to predominant wind
directions (North Westerly and South Easterly) and visibility of the power lines against the
landscape.
The power lines were ranked as highest, high, medium, low and no risk. It is recommended
that this classification be used to prioritize the proactive marking of power lines with bird
flappers in order to reduce collisions. The results show that 27% of the power lines in the
study area pose the highest risk and should therefore be marked immediately. The power
lines classified as high (1%), medium (28%) and low risk (21 %) should be marked over
short, medium and long term, respectively ..
The study demonstrated the potential of GIS in the conservation of Blue Crane. The GIS
model developed in this study can be applied in areas of similar habitat such as the Swartland or with some modifications in a slightly different habitat such as the Karoo. It is envisaged
that the results of this study will be of great value to the ESKOM (South African Electricity
Commission) and Endangered Wildlife Trust (EWT) Partnership and conservation authorities
in the effort to save the Blue Crane. / AFRIKAANSE OPSOMMING: Hierdie studie het die probleem van botsings deur Bloukraanvoëls met kraglyne in die
Overberg-omgewing van die Wes-Kaap ondersoek. Die Overberg-omgewing huisves
ongeveer 50% van Suid Afrikaanse nasionale voël se wêreldbevolking van Bloukraanvoëls,
en aangesien kraglyne normaalweg nie maklik sigbaar is teen die landskapsagtergrond nie,
verhoog dit, tesame met die biologiese eienskappe van Bloukraanvoëls, die waarskynlikheid
dat die voëls met kraglyne sal bots. Hierdie botsings met kraglyne eis minstens 20
Bloukraanvoëls per jaar, wat 'n aansienlike en beduidende aantal vir 'n kritiese bedreigde
spesie is.
Die studie het gepoog om spesialiskennis oor Bloukraanvoël-biologie, algemene gedrag en
habitatgebruik, om te sit in 'n stel reëls, wat in 'n Geografiese Inligtingstelsel (GIS)
geïntegreer is om 'n voorspellingsmodel te bou. Hierdie voorspellingsmodel is aangewend
om kraglyne wat 'n hoë risiko vir Bloukraanvoëls inhou, te identifiseer en die
waarskynlikheid vir botsings te kwantifiseer. Die model aanvaar dat die volgende
omgewingsfaktore in die Overberg-omgewing verband hou met die waarskynlikheid van
botsings, naamlik: die nabyheid van kraglyne aan waterliggame of gebiede waar voëls
saamtrek, die voorkoms van natuurlike veld, die heersende windrigtings (Noordwes en
Noordoos) en lae sigbaarheid van kraglyne teen die donker landskapsagtergrond.
Die geïdentifiseerde kraglyne is as eerste-, tweede, derde. en vierderangse prioriteit
geprioritiseer om as riglyn te dien vir die proaktiewe aanbring van flappers (wat dit ten doel
het om voëlbotsings te verminder) deur ESKOM. Die studie het bevind dat 27% van die
kraglyne in die Overberg-omgewing eersterang prioriteite is, en dat hierdie kraglyne
onmiddellik gemerk sal moet word. Die tweederang prioriteit kraglyne (1%) saloor die mediumtermyn gemerk word, terwyl die derderangse prioriteit kraglyne (28%) oor die
langtermyn gemerk sal word. Die vierde prioriteit kraglyne (21 %) kon oor die langertermyn
gemerk word.
Die studie het die omvang van die probleem, sowel as die rol van GIS in die bewaring van
die Bloukraanvoëls beklemtoon. Die GIS-model wat in die studie ontwikkel en gebruik is,
kan in soortgelyke gebiede soos die Swartland, of in ietwat verskillende omgewings soos die
Karoo getoets word, met die doelom die habitatvoorkeure van Bloukraanvoëls beter te
verstaan en navorsers te help om 'n beter begrip van die model te ontwikkel en sodoende die
resultate te verbeter. Dit word voorsien dat hierdie studie en verslag baie belangrik sal wees
vir die ESKOM-EWT Vennootskap en ander betrokke bewaringsorganisasies in 'n poging
om Bloukraanvoël-bewaring aan te help.
|
3 |
Quantifying crop damage by Grey crowned crane balearica regulorum regulorum and evaluating changes in crane distribution in the North Eastern Cape, South AfricaVan Niekerk, Mark Harry January 2011 (has links)
Complaints of crop damage by cranes on planted maize in the North Eastern Cape, South Africa, have been increasing since the mid-1990‘s, and in some instances severe losses have been reported. Crop damage by the Grey Crowned Crane Balearica regulorum regulorum near the town of Maclear (31º04´S 28º22´E), has been quantified over two growing seasons, and assessed relative to losses caused by foraging Cape Crows Corvus capensis and other feeding damage assumed to be caused by insects. Twelve fields were selected based on previous patterns of crop depredation. Maize seed in seven of the fields was treated with the chemical ‗Gaucho‘ and five fields were planted with untreated maize. In order to determine the source of losses, twenty quadrats (4 m x 4 m) randomly distributed within each field were visited on average every second day, for a period of up to twenty eight days. Results indicate that seed treatments do act as a deterrent to feeding by both cranes and crows, however crane damage is generally insignificant compared to other sources of damage. My study also reviewed past sightings data of the Grey Crowned Crane in an effort to determine if the conversion of former grassland to plantations in this region may have increased foraging activity in maize fields. The data did not allow for clear-cut conclusions regarding changes in distribution or population trends. Conclusions provide direct input into the management of agricultural areas by enabling landowners to take steps to mitigate crop damage. These mitigation measures may either involve the application of seed treatments, or the planting of low risk crops in high risk areas. Future studies should consider the ppossible detrimental effects of chemical seed treatments on crane biology.
|
Page generated in 0.0571 seconds