Counting Common Starlings: is Sturnus vulgaris invasive in rural South Africa?
- Craig, Adrian J F K, Edwards, Shelley
- Authors: Craig, Adrian J F K , Edwards, Shelley
- Date: 2024
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449344 , vital:74813 , https://doi.org/10.2989/00306525.2024.2304359
- Description: The numbers of Common Starlings Sturnus vulgaris and indigenous starling species, as well as a subset of other common birds, were recorded from October 2006 to January 2020 at 72 point-count sites along four routes (two urban and two rural) in the Eastern Cape Province of South African. In the rural habitat, Common Starlings were localised at buildings; in the urban habitat, there was no clear indication that their presence influenced the occurrence or abundance of the Red-winged Starling Onychognathus morio, a native species which has colonised towns and nests on buildings. In this region there is little evidence that Common Starlings invade areas that have not been heavily modified by human activities.
- Full Text:
- Date Issued: 2024
- Authors: Craig, Adrian J F K , Edwards, Shelley
- Date: 2024
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/449344 , vital:74813 , https://doi.org/10.2989/00306525.2024.2304359
- Description: The numbers of Common Starlings Sturnus vulgaris and indigenous starling species, as well as a subset of other common birds, were recorded from October 2006 to January 2020 at 72 point-count sites along four routes (two urban and two rural) in the Eastern Cape Province of South African. In the rural habitat, Common Starlings were localised at buildings; in the urban habitat, there was no clear indication that their presence influenced the occurrence or abundance of the Red-winged Starling Onychognathus morio, a native species which has colonised towns and nests on buildings. In this region there is little evidence that Common Starlings invade areas that have not been heavily modified by human activities.
- Full Text:
- Date Issued: 2024
Addressing the red flags in cochineal identification: The use of molecular techniques to identify cochineal insects that are used as biological control agents for invasive alien cacti
- van Steenderen, Clarke J M, Paterson, Iain D, Edwards, Shelley, Day, Michael D
- Authors: van Steenderen, Clarke J M , Paterson, Iain D , Edwards, Shelley , Day, Michael D
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423282 , vital:72044 , xlink:href="https://doi.org/10.1016/j.biocontrol.2020.104426"
- Description: Invasive Cactaceae cause considerable damage to ecosystem function and agricultural practices around the world. The most successful biological control agents used to combat this group of weeds belong to the genus Dactylopius (Hemiptera: Dactylopiidae), commonly known as ‘cochineal’. Effective control relies on selecting the correct species, or in some cases, the most effective intraspecific lineage, of cochineal for the target cactus species. Many of the Dactylopius species are so morphologically similar, and in the case of intraspecific lineages, identical, that numerous misidentifications have been made in the past. These errors have resulted in failed attempts at the biological control of some cactus species. This study aimed to generate a multi-locus genetic database to enable the accurate identification of dactylopiids. Genetic characterization was achieved through the nucleotide sequencing of three gene regions (12S rRNA, 18S rRNA, and COI) and two inter-simple sequence repeats (ISSR). Nucleotide sequences were very effective for species-level and D. tomentosus lineage-level identification, but could not distinguish between the two lineages within D. opuntiae commonly used for biological control of various Opuntia spp. Fragment analysis through the use of ISSRs successfully addressed this issue. This is the first time that a method has been developed that can distinguish between these two D. opuntiae lineages. Using the methods developed in this study, biological control practitioners can ensure that the most effective agent species and lineages are used for each cactus target weed, thus maximizing the level of control.
- Full Text:
- Date Issued: 2021
- Authors: van Steenderen, Clarke J M , Paterson, Iain D , Edwards, Shelley , Day, Michael D
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/423282 , vital:72044 , xlink:href="https://doi.org/10.1016/j.biocontrol.2020.104426"
- Description: Invasive Cactaceae cause considerable damage to ecosystem function and agricultural practices around the world. The most successful biological control agents used to combat this group of weeds belong to the genus Dactylopius (Hemiptera: Dactylopiidae), commonly known as ‘cochineal’. Effective control relies on selecting the correct species, or in some cases, the most effective intraspecific lineage, of cochineal for the target cactus species. Many of the Dactylopius species are so morphologically similar, and in the case of intraspecific lineages, identical, that numerous misidentifications have been made in the past. These errors have resulted in failed attempts at the biological control of some cactus species. This study aimed to generate a multi-locus genetic database to enable the accurate identification of dactylopiids. Genetic characterization was achieved through the nucleotide sequencing of three gene regions (12S rRNA, 18S rRNA, and COI) and two inter-simple sequence repeats (ISSR). Nucleotide sequences were very effective for species-level and D. tomentosus lineage-level identification, but could not distinguish between the two lineages within D. opuntiae commonly used for biological control of various Opuntia spp. Fragment analysis through the use of ISSRs successfully addressed this issue. This is the first time that a method has been developed that can distinguish between these two D. opuntiae lineages. Using the methods developed in this study, biological control practitioners can ensure that the most effective agent species and lineages are used for each cactus target weed, thus maximizing the level of control.
- Full Text:
- Date Issued: 2021
The cicada genus Tugelana Distant, 1912 (Hemiptera, Cicadidae): phylogenetic position and conservation status
- Villet, Martin H, Edwards, Shelley
- Authors: Villet, Martin H , Edwards, Shelley
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440628 , vital:73798 , https://africaninvertebrates.pensoft.net/article/66891/
- Description: The cicada genus Tugelana Distant, 1912 is monotypic and endemic to south-eastern Africa. Material was not available for a recent molecular phylogeny of its tribe, so its precise phylogenetic placement is unestablished. Consequently, a 627 bp sequence of the cytochrome oxidase gene was obtained and its candidate relatives identified as several species of Platypleura Amyot and Audinet-Serville, 1843 using the BOLD Identification System and NCBI Genbank’s BLAST. Bayesian inference analyses indicated that the type species, the Maputaland Orangewing Cicada Tugelana butleri Distant, 1912, is closely related to the Dune Koko Orangewing Cicada Platypleura zuluensis Villet, 1989, which has a geographical distribution that is parapatric with T. butleri and which has aberrant genitalia for a member of Platypleura. This pair of species is placed fairly deep within the African clade of Platypleura. We therefore formally recognized Platypleura Amyot and Audinet-Serville, 1843 as a senior synonym of Tugelana Distant, 1912, syn. nov., and assign T. butleri Distant, 1912 to Platypleura as Platypleura butleri (Distant 1912), comb. nov. The species occurs on the wooded grasslands of the Maputaland coastal plateau east of Lebombo Mountains and south of Maputo Bay. Its Extent of Occurrence is about 6360 km2, which would qualify it as Vulnerable under the IUCN’s classification criteria for conservation status.
- Full Text:
- Date Issued: 2021
- Authors: Villet, Martin H , Edwards, Shelley
- Date: 2021
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440628 , vital:73798 , https://africaninvertebrates.pensoft.net/article/66891/
- Description: The cicada genus Tugelana Distant, 1912 is monotypic and endemic to south-eastern Africa. Material was not available for a recent molecular phylogeny of its tribe, so its precise phylogenetic placement is unestablished. Consequently, a 627 bp sequence of the cytochrome oxidase gene was obtained and its candidate relatives identified as several species of Platypleura Amyot and Audinet-Serville, 1843 using the BOLD Identification System and NCBI Genbank’s BLAST. Bayesian inference analyses indicated that the type species, the Maputaland Orangewing Cicada Tugelana butleri Distant, 1912, is closely related to the Dune Koko Orangewing Cicada Platypleura zuluensis Villet, 1989, which has a geographical distribution that is parapatric with T. butleri and which has aberrant genitalia for a member of Platypleura. This pair of species is placed fairly deep within the African clade of Platypleura. We therefore formally recognized Platypleura Amyot and Audinet-Serville, 1843 as a senior synonym of Tugelana Distant, 1912, syn. nov., and assign T. butleri Distant, 1912 to Platypleura as Platypleura butleri (Distant 1912), comb. nov. The species occurs on the wooded grasslands of the Maputaland coastal plateau east of Lebombo Mountains and south of Maputo Bay. Its Extent of Occurrence is about 6360 km2, which would qualify it as Vulnerable under the IUCN’s classification criteria for conservation status.
- Full Text:
- Date Issued: 2021
No evidence of genetic structure in a sky island endemic: implications for population persistence under a shrinking thermal niche
- Oswald, Krista N, Edwards, Shelley, Lee, Alan T K, Cunningham, Susan J, Smit, Ben
- Authors: Oswald, Krista N , Edwards, Shelley , Lee, Alan T K , Cunningham, Susan J , Smit, Ben
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440558 , vital:73793 , https://www.authorea.com/doi/full/10.22541/au.157901262.24420308
- Description: Mountain habitats physically isolated from one another (“sky islands”) represent a unique system for studying dispersal in seemingly isolated populations. The Cape Fold Belt of southwest South Africa forms a sky island archipelago of high-altitude mountain fynbos of which the Cape Rockjumper Chaetops frenatus is an avian-endemic. Continued contraction of habitat due to increasing temperatures may be causing further isolation of C. frenatus populations beyond their dispersal capacities, resulting in currently declining populations in warmer areas of their habitat. In this study, we sequenced two mitochondrial loci and one nuclear locus of 73 C. frenatus samples from 13 localities representing 8 mountain ranges. We found (1) low overall genetic diversity, (2) no evidence for geographically-based genetic structuring, and (3) no evidence for inbreeding within localities. While this may indicate birds are effectively dispersing, it may also indicate strong selective pressure is being placed on their specific genotype. Haplotype networks suggested that C. frenatus may have experienced a bottleneck or founder effect in their recent genetic past —- a result supported by a significantly negative Tajima’s D value. As the first avian genetic study to arise from a range-restricted species of the Cape Fold Belt sky islands, our results show no evidence that C. frenatus are unable to disperse across inhospitable lowland habitat, and thus may not experience isolation due to climate change. We thus potentially found further support that selective pressure in species with highly specialized habitat niches may have a stronger effect than dispersal limitations.
- Full Text:
- Date Issued: 2020
- Authors: Oswald, Krista N , Edwards, Shelley , Lee, Alan T K , Cunningham, Susan J , Smit, Ben
- Date: 2020
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440558 , vital:73793 , https://www.authorea.com/doi/full/10.22541/au.157901262.24420308
- Description: Mountain habitats physically isolated from one another (“sky islands”) represent a unique system for studying dispersal in seemingly isolated populations. The Cape Fold Belt of southwest South Africa forms a sky island archipelago of high-altitude mountain fynbos of which the Cape Rockjumper Chaetops frenatus is an avian-endemic. Continued contraction of habitat due to increasing temperatures may be causing further isolation of C. frenatus populations beyond their dispersal capacities, resulting in currently declining populations in warmer areas of their habitat. In this study, we sequenced two mitochondrial loci and one nuclear locus of 73 C. frenatus samples from 13 localities representing 8 mountain ranges. We found (1) low overall genetic diversity, (2) no evidence for geographically-based genetic structuring, and (3) no evidence for inbreeding within localities. While this may indicate birds are effectively dispersing, it may also indicate strong selective pressure is being placed on their specific genotype. Haplotype networks suggested that C. frenatus may have experienced a bottleneck or founder effect in their recent genetic past —- a result supported by a significantly negative Tajima’s D value. As the first avian genetic study to arise from a range-restricted species of the Cape Fold Belt sky islands, our results show no evidence that C. frenatus are unable to disperse across inhospitable lowland habitat, and thus may not experience isolation due to climate change. We thus potentially found further support that selective pressure in species with highly specialized habitat niches may have a stronger effect than dispersal limitations.
- Full Text:
- Date Issued: 2020
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