Drowning in data, thirsty for information and starved for understanding: A biodiversity information hub for cooperative environmental monitoring in South Africa
- MacFadyen, Sandra, Allsopp, Nicky, Altwegg, Res, Archibald, Sally, Botha, Judith, Bradshaw, Karen L, Carruthers, Jane, De Klerk, Helen, de Vos, Alta, Distiller, Greg, Foord, Stefan, Freitag-Ronaldson, Stefanie, Gibbs, Richard, Hamer, Michelle, Landi, Pietro, MacFayden, Duncan, Manuel, Jeffrey, Midgley, Guy, Moncrieff, Glenn, Munch, Zahn, Mutanga, Onisimo, Sershen, Nenguda, Rendani, Ngwenya, Mzabalazo, Parker, Daniel M, Peel, Mike, Power, John, Pretorius, Joachim, Ramdhani, Syd, Robertson, Mark P, Rushworth, Ian, Skowno, Andrew, Slingsby, Jasper, Turner, Andrew, Visser, Vernon, van Wageningen, Gerhard, Hui, Cang
- Authors: MacFadyen, Sandra , Allsopp, Nicky , Altwegg, Res , Archibald, Sally , Botha, Judith , Bradshaw, Karen L , Carruthers, Jane , De Klerk, Helen , de Vos, Alta , Distiller, Greg , Foord, Stefan , Freitag-Ronaldson, Stefanie , Gibbs, Richard , Hamer, Michelle , Landi, Pietro , MacFayden, Duncan , Manuel, Jeffrey , Midgley, Guy , Moncrieff, Glenn , Munch, Zahn , Mutanga, Onisimo , Sershen , Nenguda, Rendani , Ngwenya, Mzabalazo , Parker, Daniel M , Peel, Mike , Power, John , Pretorius, Joachim , Ramdhani, Syd , Robertson, Mark P , Rushworth, Ian , Skowno, Andrew , Slingsby, Jasper , Turner, Andrew , Visser, Vernon , van Wageningen, Gerhard , Hui, Cang
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/415624 , vital:71271 , xlink:href="https://doi.org/10.1016/j.biocon.2022.109736"
- Description: The world is firmly cemented in a notitian age (Latin: notitia, meaning data) – drowning in data, yet thirsty for information and the synthesis of knowledge into understanding. As concerns over biodiversity declines escalate, the volume, diversity and speed at which new environmental and ecological data are generated has increased exponentially. Data availability primes the research and discovery engine driving biodiversity conservation. South Africa (SA) is poised to become a world leader in biodiversity conservation. However, continent-wide resource limitations hamper the establishment of inclusive technologies and robust platforms and tools for biodiversity informatics. In this perspectives piece, we bring together the opinions of 37 co-authors from 20 different departments, across 10 SA universities, 7 national and provincial conservation research agencies, and various institutes and private conservation, research and management bodies, to develop a way forward for biodiversity informatics in SA. We propose the development of a SA Biodiversity Informatics Hub and describe the essential components necessary for its design, implementation and sustainability. We emphasise the importance of developing a culture of cooperation, collaboration and interoperability among custodians of biodiversity data to establish operational workflows for data synthesis. However, our biggest challenges are misgivings around data sharing and multidisciplinary collaboration.
- Full Text:
- Date Issued: 2022
- Authors: MacFadyen, Sandra , Allsopp, Nicky , Altwegg, Res , Archibald, Sally , Botha, Judith , Bradshaw, Karen L , Carruthers, Jane , De Klerk, Helen , de Vos, Alta , Distiller, Greg , Foord, Stefan , Freitag-Ronaldson, Stefanie , Gibbs, Richard , Hamer, Michelle , Landi, Pietro , MacFayden, Duncan , Manuel, Jeffrey , Midgley, Guy , Moncrieff, Glenn , Munch, Zahn , Mutanga, Onisimo , Sershen , Nenguda, Rendani , Ngwenya, Mzabalazo , Parker, Daniel M , Peel, Mike , Power, John , Pretorius, Joachim , Ramdhani, Syd , Robertson, Mark P , Rushworth, Ian , Skowno, Andrew , Slingsby, Jasper , Turner, Andrew , Visser, Vernon , van Wageningen, Gerhard , Hui, Cang
- Date: 2022
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/415624 , vital:71271 , xlink:href="https://doi.org/10.1016/j.biocon.2022.109736"
- Description: The world is firmly cemented in a notitian age (Latin: notitia, meaning data) – drowning in data, yet thirsty for information and the synthesis of knowledge into understanding. As concerns over biodiversity declines escalate, the volume, diversity and speed at which new environmental and ecological data are generated has increased exponentially. Data availability primes the research and discovery engine driving biodiversity conservation. South Africa (SA) is poised to become a world leader in biodiversity conservation. However, continent-wide resource limitations hamper the establishment of inclusive technologies and robust platforms and tools for biodiversity informatics. In this perspectives piece, we bring together the opinions of 37 co-authors from 20 different departments, across 10 SA universities, 7 national and provincial conservation research agencies, and various institutes and private conservation, research and management bodies, to develop a way forward for biodiversity informatics in SA. We propose the development of a SA Biodiversity Informatics Hub and describe the essential components necessary for its design, implementation and sustainability. We emphasise the importance of developing a culture of cooperation, collaboration and interoperability among custodians of biodiversity data to establish operational workflows for data synthesis. However, our biggest challenges are misgivings around data sharing and multidisciplinary collaboration.
- Full Text:
- Date Issued: 2022
A qualitative ecological risk assessment of the invasive Nile tilapia, Oreochromis niloticus in a sub-tropical African river system (Limpopo River, South Africa)
- Zengeya, Tsungai A, Robertson, Mark P, Booth, Anthony J, Chimimba, Christian T
- Authors: Zengeya, Tsungai A , Robertson, Mark P , Booth, Anthony J , Chimimba, Christian T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123575 , vital:35457 , https://doi.10.1002/aqc.2258
- Description: 1. This study outlines the development of a qualitative risk assessment method and its application as a screening tool for determining the risk of establishment and spread of the invasive Nile tilapia, Oreochromis niloticus (Linnaeus, 1758), within the central sub-catchment of the Limpopo River basin in northern South Africa. 2. The assessment used known physiological tolerance limits of O. niloticus in relation to minimum water temperature, presence or absence of dams, seasonality of river flows, and the presence of indigenous fish species of concern to identify river systems that would be suitable for O. niloticus establishment. 3. River sections along the Limpopo main river channel and the immediate reaches of its associated tributaries east of the Limpopo/Lephalala river confluence along the Botswana–South Africa–Zimbabwe border were identified as being highly vulnerable to O. niloticus invasion. Rivers in the upper Bushveld catchment (Upper Limpopo, Mogalakwena, Lephalala, Mokolo, Matlabas and Crocodile rivers) were categorized as of medium ecological risk, while headwater streams were considered to be of low ecological risk. The decrease in vulnerability between lowveld and highveld river sections was mainly a function of low water temperatures (8–12˚C) associated with increasing altitude. 4. Oreochromis niloticus is already established in the lower catchment of the Limpopo River basin where indigenous congenerics are at an extinction risk through hybridization and competition exclusion. Oreochromis niloticus, therefore, poses an ecologically unacceptable risk to river systems in the upper catchment where it is yet to establish. The current risk assessment model provides a useful preliminary framework for the identification of river systems that are vulnerable to an O. niloticus invasion where conservation measures should be directed and implemented to prevent its introduction and spread within the Limpopo river system.
- Full Text:
- Date Issued: 2013
- Authors: Zengeya, Tsungai A , Robertson, Mark P , Booth, Anthony J , Chimimba, Christian T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123575 , vital:35457 , https://doi.10.1002/aqc.2258
- Description: 1. This study outlines the development of a qualitative risk assessment method and its application as a screening tool for determining the risk of establishment and spread of the invasive Nile tilapia, Oreochromis niloticus (Linnaeus, 1758), within the central sub-catchment of the Limpopo River basin in northern South Africa. 2. The assessment used known physiological tolerance limits of O. niloticus in relation to minimum water temperature, presence or absence of dams, seasonality of river flows, and the presence of indigenous fish species of concern to identify river systems that would be suitable for O. niloticus establishment. 3. River sections along the Limpopo main river channel and the immediate reaches of its associated tributaries east of the Limpopo/Lephalala river confluence along the Botswana–South Africa–Zimbabwe border were identified as being highly vulnerable to O. niloticus invasion. Rivers in the upper Bushveld catchment (Upper Limpopo, Mogalakwena, Lephalala, Mokolo, Matlabas and Crocodile rivers) were categorized as of medium ecological risk, while headwater streams were considered to be of low ecological risk. The decrease in vulnerability between lowveld and highveld river sections was mainly a function of low water temperatures (8–12˚C) associated with increasing altitude. 4. Oreochromis niloticus is already established in the lower catchment of the Limpopo River basin where indigenous congenerics are at an extinction risk through hybridization and competition exclusion. Oreochromis niloticus, therefore, poses an ecologically unacceptable risk to river systems in the upper catchment where it is yet to establish. The current risk assessment model provides a useful preliminary framework for the identification of river systems that are vulnerable to an O. niloticus invasion where conservation measures should be directed and implemented to prevent its introduction and spread within the Limpopo river system.
- Full Text:
- Date Issued: 2013
Ecological niche modeling of the invasive potential of Nile tilapia Oreochromis niloticus in African river systems: concerns and implications for the conservation of indigenous congenerics
- Zengeya, Tsungai A, Robertson, Mark P, Booth, Anthony J, Chimimba, Christian T
- Authors: Zengeya, Tsungai A , Robertson, Mark P , Booth, Anthony J , Chimimba, Christian T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124341 , vital:35596 , https://doi.10.1007/s10530-012-0386-7
- Description: This study applied ecological niche models to determine the potential invasive range of Nile tilapia, Oreochromis niloticus, with a particular focus on river systems in southern Africa where it is now established and spreading. Computational tools such as niche models are useful in predicting the potential range of invasive species, but there are limitations to their application. In particular, models trained on native records may fail to predict the full extent of an invasion. This failure is often attributed to changes in either the niche of the invading species or the variables used to develop the models. In this study, we therefore evaluated the differences in the predictive power of models trained with different environmental variables, the effect of species range (native vs. introduced) on model performance and assessed whether or not there is evidence suggestive of a niche shift in Nile tilapia following its introduction. Niche models were constructed using Maxent and the degree of niche similarity was assessed using Schoener‘s index. Null models were used to test for significance. Model performance and niche conservatism varied significantly with variable selection and species range. This indicates that the environmental conditions available to Nile tilapia in its native and introduced ranges are not congruent. Nile tilapia exhibited broad invasive potential over most of southern Africa that overlaps the natural range of endemic congenerics. Of particular concern are areas which are free of exotic species but are now vulnerable due to the promotion of fish introductions mainly for aquaculture and sport fishing.
- Full Text:
- Date Issued: 2013
- Authors: Zengeya, Tsungai A , Robertson, Mark P , Booth, Anthony J , Chimimba, Christian T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124341 , vital:35596 , https://doi.10.1007/s10530-012-0386-7
- Description: This study applied ecological niche models to determine the potential invasive range of Nile tilapia, Oreochromis niloticus, with a particular focus on river systems in southern Africa where it is now established and spreading. Computational tools such as niche models are useful in predicting the potential range of invasive species, but there are limitations to their application. In particular, models trained on native records may fail to predict the full extent of an invasion. This failure is often attributed to changes in either the niche of the invading species or the variables used to develop the models. In this study, we therefore evaluated the differences in the predictive power of models trained with different environmental variables, the effect of species range (native vs. introduced) on model performance and assessed whether or not there is evidence suggestive of a niche shift in Nile tilapia following its introduction. Niche models were constructed using Maxent and the degree of niche similarity was assessed using Schoener‘s index. Null models were used to test for significance. Model performance and niche conservatism varied significantly with variable selection and species range. This indicates that the environmental conditions available to Nile tilapia in its native and introduced ranges are not congruent. Nile tilapia exhibited broad invasive potential over most of southern Africa that overlaps the natural range of endemic congenerics. Of particular concern are areas which are free of exotic species but are now vulnerable due to the promotion of fish introductions mainly for aquaculture and sport fishing.
- Full Text:
- Date Issued: 2013
A PCA-based modelling technique for predicting environmental suitability for organisms from presence records
- Robertson, Mark P, Caithness, N, Villet, Martin H
- Authors: Robertson, Mark P , Caithness, N , Villet, Martin H
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442609 , vital:74014 , https://doi.org/10.1046/j.1472-4642.2001.00094.x
- Description: We present a correlative modelling technique that uses locality records (associated with species presence) and a set of predictor variables to produce a statistically justifiable probability response surface for a target species. The probability response surface indicates the suitability of each grid cell in a map for the target species in terms of the suite of predictor variables. The technique constructs a hyperspace for the target species using principal component axes derived from a principal components analysis performed on a training dataset. The training dataset comprises the values of the predictor variables associated with the localities where the species has been recorded as present. The origin of this hyperspace is taken to characterize the centre of the niche of the organism. All the localities (grid‐cells) in the map region are then fitted into this hyperspace using the values of the predictor variables at these localities (the prediction dataset). The Euclidean distance from any locality to the origin of the hyperspace gives a measure of the ‘centrality’ of that locality in the hyperspace. These distances are used to derive probability values for each grid cell in the map region. The modelling technique was applied to bioclimatic data to predict bioclimatic suitability for three alien invasive plant species (Lantana camara L., Ricinus communis L. and Solanum mauritianum Scop.) in South Africa, Lesotho and Swaziland. The models were tested against independent test records by calculating area under the curve (AUC) values of receiver operator characteristic (ROC) curves and kappa statistics. There was good agreement between the models and the independent test records. The pre‐processing of climatic variable data to reduce the deleterious effects of multicollinearity, and the use of stopping rules to prevent overfitting of the models are important aspects of the modelling process.
- Full Text:
- Date Issued: 2001
- Authors: Robertson, Mark P , Caithness, N , Villet, Martin H
- Date: 2001
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/442609 , vital:74014 , https://doi.org/10.1046/j.1472-4642.2001.00094.x
- Description: We present a correlative modelling technique that uses locality records (associated with species presence) and a set of predictor variables to produce a statistically justifiable probability response surface for a target species. The probability response surface indicates the suitability of each grid cell in a map for the target species in terms of the suite of predictor variables. The technique constructs a hyperspace for the target species using principal component axes derived from a principal components analysis performed on a training dataset. The training dataset comprises the values of the predictor variables associated with the localities where the species has been recorded as present. The origin of this hyperspace is taken to characterize the centre of the niche of the organism. All the localities (grid‐cells) in the map region are then fitted into this hyperspace using the values of the predictor variables at these localities (the prediction dataset). The Euclidean distance from any locality to the origin of the hyperspace gives a measure of the ‘centrality’ of that locality in the hyperspace. These distances are used to derive probability values for each grid cell in the map region. The modelling technique was applied to bioclimatic data to predict bioclimatic suitability for three alien invasive plant species (Lantana camara L., Ricinus communis L. and Solanum mauritianum Scop.) in South Africa, Lesotho and Swaziland. The models were tested against independent test records by calculating area under the curve (AUC) values of receiver operator characteristic (ROC) curves and kappa statistics. There was good agreement between the models and the independent test records. The pre‐processing of climatic variable data to reduce the deleterious effects of multicollinearity, and the use of stopping rules to prevent overfitting of the models are important aspects of the modelling process.
- Full Text:
- Date Issued: 2001
Discriminant analysis of the honeybee populations of southwestern Africa
- Radloff, Sarah E, Hepburn, H Randall, Robertson, Mark P, van Hille, Robert P, Davidson, Z, Villet, Martin H
- Authors: Radloff, Sarah E , Hepburn, H Randall , Robertson, Mark P , van Hille, Robert P , Davidson, Z , Villet, Martin H
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451370 , vital:75044 , https://hdl.handle.net/10520/AJA10213589_176
- Description: The morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in southwestern Africa. There is a discrete homogeneous population in northern South Africa and southern Namibia recognized as the subspecies A m. scutellata, a discrete population in northern Namibia recognized as A m. adansonii and a hybrid population between them.
- Full Text: false
- Date Issued: 1996
- Authors: Radloff, Sarah E , Hepburn, H Randall , Robertson, Mark P , van Hille, Robert P , Davidson, Z , Villet, Martin H
- Date: 1996
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/451370 , vital:75044 , https://hdl.handle.net/10520/AJA10213589_176
- Description: The morphometric characters and sting pheromones of worker honeybees, Apis mellifera Linnaeus, were analysed by multivariate methods to characterize their populations in southwestern Africa. There is a discrete homogeneous population in northern South Africa and southern Namibia recognized as the subspecies A m. scutellata, a discrete population in northern Namibia recognized as A m. adansonii and a hybrid population between them.
- Full Text: false
- Date Issued: 1996
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