Pub Date : 2021-10-02DOI: 10.1080/15627020.2021.2007418
A. Lokasola, Cédric Botshuna Lotana, Guy Crispin Gembu Tungaluna, B. D. Akaibe, M. Jirků, V. Gvoždík
In the central Congolian lowland forests we discovered for the first time Panaspis breviceps, a rarely found scincid lizard from the Central African riparian forests. Given that the Central African forests exhibit heterogeneity in the distribution of environmental characteristics and forms distinct ecoregions, the question arises as to how this newly discovered population compares with other populations in Central Africa and particularly in the Congolian lowland forests. We reviewed the distribution records of this species and examined and compared new and available genetic data (mitochondrial DNA). Maximum likelihood phylogenetic analysis revealed the existence of two evolutionary lineages differing by 2.0% in 16S rRNA. One lineage occurs in and around the southern Cameroon Highlands, but its distribution southwards is poorly documented. The other lineage includes the western, central and eastern populations of the Congo Basin, suggesting certain biogeographic connectivity across the Congolian forests. These results support the hypothesis of limited biogeographic barriers to the distribution of lizards in the Congolian lowland forests, but this remains to be tested using additional independent markers, denser sampling and multiple species.
{"title":"New Distributional Data and Genetic Variation of Panaspis breviceps (Squamata: Scincidae) Indicate a Biogeographic Connection across the Congo Basin","authors":"A. Lokasola, Cédric Botshuna Lotana, Guy Crispin Gembu Tungaluna, B. D. Akaibe, M. Jirků, V. Gvoždík","doi":"10.1080/15627020.2021.2007418","DOIUrl":"https://doi.org/10.1080/15627020.2021.2007418","url":null,"abstract":"In the central Congolian lowland forests we discovered for the first time Panaspis breviceps, a rarely found scincid lizard from the Central African riparian forests. Given that the Central African forests exhibit heterogeneity in the distribution of environmental characteristics and forms distinct ecoregions, the question arises as to how this newly discovered population compares with other populations in Central Africa and particularly in the Congolian lowland forests. We reviewed the distribution records of this species and examined and compared new and available genetic data (mitochondrial DNA). Maximum likelihood phylogenetic analysis revealed the existence of two evolutionary lineages differing by 2.0% in 16S rRNA. One lineage occurs in and around the southern Cameroon Highlands, but its distribution southwards is poorly documented. The other lineage includes the western, central and eastern populations of the Congo Basin, suggesting certain biogeographic connectivity across the Congolian forests. These results support the hypothesis of limited biogeographic barriers to the distribution of lizards in the Congolian lowland forests, but this remains to be tested using additional independent markers, denser sampling and multiple species.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"312 - 318"},"PeriodicalIF":1.1,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44152094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-10-02DOI: 10.1080/15627020.2021.2006779
P. E. Ndimele, F. G. Owodeinde, E. Clarke, Olufemi Olusegun Whenu, Olufemi Olabode Joseph
The black-chinned tilapia (Sarotherodon melanotheron) is a member of the cichlid family, which can be cultured to complement the output from a predominantly catfish aquaculture industry in Nigeria. In order to achieve this objective, it is important to study the bio-ecology of the fish to ascertain the exploitation status and the potential for culture. Fish were collected monthly from February to November 2018 from three sampling sites (Topo, Akarakumo and Ajido) in Badagry Creek, Lagos, Nigeria using gears like cast net, gill nets and traps. The samples were analysed for length-weight relationship, population parameters and feeding preference. The population dynamics of the stock was assessed by the Von Bertalanffy growth model (VBGM) using Electronic Length Frequency Analysis. The parameters of VBGM; asymptomatic length (L∞) and growth coefficient (K) were 20.46 cm and 0.62 year−1, respectively. The growth performance index (Ǿ) was 2.41 and the potential longevity (tmax) was 4.84 years. The total, natural and fishing mortalities were 1.06, 0.68 and 0.38 year−1, respectively. The exploitation rate was estimated as 0.36. The length at first maturity (L50) was 13.79 cm and the length at first capture (Lc) was 12.27 cm. E0.1, E0.5 and Emax are 0.60, 0.38 and 0.70, respectively. The dominant food items in the gut of the fish belong to the algae phylum, Chlorophyta. The study showed that S. melanotheron from Badagry Creek are planktivores and the exploitation rate of the fish is currently close to optimum and should be sustained at this level to prevent overexploitation.
{"title":"Population parameters, exploitation rate and diet of black-chinned Tilapia, Sarotherodon melanotheron Rüppell, 1852 (Pisces: Cichlidae), from Badagry Creek, Lagos, Nigeria","authors":"P. E. Ndimele, F. G. Owodeinde, E. Clarke, Olufemi Olusegun Whenu, Olufemi Olabode Joseph","doi":"10.1080/15627020.2021.2006779","DOIUrl":"https://doi.org/10.1080/15627020.2021.2006779","url":null,"abstract":"The black-chinned tilapia (Sarotherodon melanotheron) is a member of the cichlid family, which can be cultured to complement the output from a predominantly catfish aquaculture industry in Nigeria. In order to achieve this objective, it is important to study the bio-ecology of the fish to ascertain the exploitation status and the potential for culture. Fish were collected monthly from February to November 2018 from three sampling sites (Topo, Akarakumo and Ajido) in Badagry Creek, Lagos, Nigeria using gears like cast net, gill nets and traps. The samples were analysed for length-weight relationship, population parameters and feeding preference. The population dynamics of the stock was assessed by the Von Bertalanffy growth model (VBGM) using Electronic Length Frequency Analysis. The parameters of VBGM; asymptomatic length (L∞) and growth coefficient (K) were 20.46 cm and 0.62 year−1, respectively. The growth performance index (Ǿ) was 2.41 and the potential longevity (tmax) was 4.84 years. The total, natural and fishing mortalities were 1.06, 0.68 and 0.38 year−1, respectively. The exploitation rate was estimated as 0.36. The length at first maturity (L50) was 13.79 cm and the length at first capture (Lc) was 12.27 cm. E0.1, E0.5 and Emax are 0.60, 0.38 and 0.70, respectively. The dominant food items in the gut of the fish belong to the algae phylum, Chlorophyta. The study showed that S. melanotheron from Badagry Creek are planktivores and the exploitation rate of the fish is currently close to optimum and should be sustained at this level to prevent overexploitation.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"279 - 291"},"PeriodicalIF":1.1,"publicationDate":"2021-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48748203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/15627020.2021.1952896
R. Lyamuya, K. M. Hariohay, E. Masenga, J. Bukombe, Grayson Mwakalebe, Maulid L. Mdaki, Ally K. Nkwabi, R. Fyumagwa, E. Røskaft
Globally, traffic associated with roads that pass through protected areas are the cause of many negative impacts on wildlife, such as wildlife roadkill, which has occurred within the Serengeti ecosystem. A 200 km stretch of gravel road networks that passes through the Serengeti ecosystem was surveyed in 2015 for five consecutive days during each study period during the wet and dry seasons, between March and August 2015, to document the magnitude, patterns and composition of wildlife roadkill. We found a total of 51 wildlife roadkills that consisted of 26 species of wild animals and included 18 bird and 8 mammal species. Bird species (60.8%) were more frequently killed than mammal species (39.2%). Moreover, a higher incidence of wildlife roadkill was recorded in the morning (56.9%) than in the afternoon (43.1%) and more mammals (51.7%) than birds (48.3%) were recorded in the morning. Greater numbers of wildlife roadkill were recorded along road segments with good road conditions (69.4%) that were wider (>8 m) and with higher traffic volumes than along roads with poor conditions (30.6%). Overall, the Cape hare (Lepus capensis) was the most frequently killed species (17.6%) among the mammals, whereas the helmeted guineafowl (Numida meleagris) (13.7%) was most frequently killed among the avifauna. To reduce the number of roadkill incidents, we recommend changing driver speeding behaviours by installing wildlife-warning signage that consists of picture-based signs, because they have been proved to be more effective than word-based signs to reduce speeds and hence, reduce collisions. Additionally, the responsible management authorities should provide education to drivers on safe driving and enforcement of laws and regulations. Further, policy briefings that focus on wildlife roadkill should be made available to assist decision-makers and engineers to improve road design in protected areas.
{"title":"Magnitude, Patterns and Composition of Wildlife Roadkill in the Serengeti Ecosystem, Northern Tanzania","authors":"R. Lyamuya, K. M. Hariohay, E. Masenga, J. Bukombe, Grayson Mwakalebe, Maulid L. Mdaki, Ally K. Nkwabi, R. Fyumagwa, E. Røskaft","doi":"10.1080/15627020.2021.1952896","DOIUrl":"https://doi.org/10.1080/15627020.2021.1952896","url":null,"abstract":"Globally, traffic associated with roads that pass through protected areas are the cause of many negative impacts on wildlife, such as wildlife roadkill, which has occurred within the Serengeti ecosystem. A 200 km stretch of gravel road networks that passes through the Serengeti ecosystem was surveyed in 2015 for five consecutive days during each study period during the wet and dry seasons, between March and August 2015, to document the magnitude, patterns and composition of wildlife roadkill. We found a total of 51 wildlife roadkills that consisted of 26 species of wild animals and included 18 bird and 8 mammal species. Bird species (60.8%) were more frequently killed than mammal species (39.2%). Moreover, a higher incidence of wildlife roadkill was recorded in the morning (56.9%) than in the afternoon (43.1%) and more mammals (51.7%) than birds (48.3%) were recorded in the morning. Greater numbers of wildlife roadkill were recorded along road segments with good road conditions (69.4%) that were wider (>8 m) and with higher traffic volumes than along roads with poor conditions (30.6%). Overall, the Cape hare (Lepus capensis) was the most frequently killed species (17.6%) among the mammals, whereas the helmeted guineafowl (Numida meleagris) (13.7%) was most frequently killed among the avifauna. To reduce the number of roadkill incidents, we recommend changing driver speeding behaviours by installing wildlife-warning signage that consists of picture-based signs, because they have been proved to be more effective than word-based signs to reduce speeds and hence, reduce collisions. Additionally, the responsible management authorities should provide education to drivers on safe driving and enforcement of laws and regulations. Further, policy briefings that focus on wildlife roadkill should be made available to assist decision-makers and engineers to improve road design in protected areas.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"173 - 180"},"PeriodicalIF":1.1,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48029571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/15627020.2021.1976077
Joaquín Verdú Ricoy, P. Mashinini, J. Goedhals, N. Heideman
The skink Mochlus sundevallii is widespread throughout the African continent, but no detailed research on its ecology, reproduction and sexual dimorphism patterns has been performed yet. Here we address phenotypic and ecological data of M. sundevallii from the southernmost part of its distribution, using multiple populations from Southern Africa (mostly from South Africa) collected throughout different seasons. We aimed to assess the degree of intersexual and seasonal differences in morphological and reproductive aspects, as well as their experienced predation pressure. Morphological analyses confirmed that the species exhibits sexual dimorphism, evidenced by a larger body size for females and larger heads and longer limbs for males. However, tail autotomy (used as an estimation of predation rate) was found to be similar for both sexes and seasonally stable. Overall, the reproductive cycles of males and females were synchronised across the seasons, for an optimal breeding period during spring and summer, but males showed certain spermatogenic activity throughout the whole year.
{"title":"Reproduction, Sexual Dimorphism and Predation in Mochlus sundevallii in Southern Africa (Reptilia: Sauria, Scincidae)","authors":"Joaquín Verdú Ricoy, P. Mashinini, J. Goedhals, N. Heideman","doi":"10.1080/15627020.2021.1976077","DOIUrl":"https://doi.org/10.1080/15627020.2021.1976077","url":null,"abstract":"The skink Mochlus sundevallii is widespread throughout the African continent, but no detailed research on its ecology, reproduction and sexual dimorphism patterns has been performed yet. Here we address phenotypic and ecological data of M. sundevallii from the southernmost part of its distribution, using multiple populations from Southern Africa (mostly from South Africa) collected throughout different seasons. We aimed to assess the degree of intersexual and seasonal differences in morphological and reproductive aspects, as well as their experienced predation pressure. Morphological analyses confirmed that the species exhibits sexual dimorphism, evidenced by a larger body size for females and larger heads and longer limbs for males. However, tail autotomy (used as an estimation of predation rate) was found to be similar for both sexes and seasonally stable. Overall, the reproductive cycles of males and females were synchronised across the seasons, for an optimal breeding period during spring and summer, but males showed certain spermatogenic activity throughout the whole year.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"213 - 221"},"PeriodicalIF":1.1,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45301006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/15627020.2021.1980103
J. Scheun, R. Campbell, A. Ganswindt, T. McIntyre
Despite the commonly held belief that reptiles are immune to extreme temperatures, global warming is predicted to result in the loss of 40% of all reptile species by 2080. In order to understand the effects of elevated temperature on African reptile physiology and health, additional research is required. We studied the physiological stress response of sungazer lizards (Smaug giganteus) facing elevated temperatures within captivity. Control animals (1M, 2F) were kept at 30 °C throughout the 13-week study period. Test animals (1M, 2F) were exposed to 30 °C for four weeks (stage 1), 39 °C for six weeks (stage 2) and 30 °C for three weeks (stage 3). Faecal samples were collected from both control and test animals to monitor faecal glucocorticoid metabolite (fGCM) concentrations as a proxy of physiological stress. Although the fGCM levels of control females remained constant, test females showed an acute fGCM increase following the increase and subsequent decrease of temperatures. The test male had significantly higher fGCM levels during stage 3, compared with stage 1 and 2. The control male, although displaying constant fGCM levels throughout the study, had higher fGCM levels than the test male. The results indicate that a considerable temporal increase in environmental temperature did not lead to chronically elevated adrenocortical activity in sungazer lizards. It is likely that inherent traits within the species allow the species to adapt to such changes. Furthermore, the endangered status of the species and limited availability of study animals restricted the sample size in this study to a few, captive-based lizards. Therefore, although our results are an important addition to reptile conservation, they should be extrapolated to free-ranging populations with caution. Future research should consider the effects of chronically elevated temperature in relation to water and food shortages, as well as interindividual variation in physiological responses.
{"title":"Hot and Bothered: Alterations in Faecal Glucocorticoid Metabolite Concentrations of the Sungazer Lizard, Smaug giganteus, in Response to an Increase in Environmental Temperature","authors":"J. Scheun, R. Campbell, A. Ganswindt, T. McIntyre","doi":"10.1080/15627020.2021.1980103","DOIUrl":"https://doi.org/10.1080/15627020.2021.1980103","url":null,"abstract":"Despite the commonly held belief that reptiles are immune to extreme temperatures, global warming is predicted to result in the loss of 40% of all reptile species by 2080. In order to understand the effects of elevated temperature on African reptile physiology and health, additional research is required. We studied the physiological stress response of sungazer lizards (Smaug giganteus) facing elevated temperatures within captivity. Control animals (1M, 2F) were kept at 30 °C throughout the 13-week study period. Test animals (1M, 2F) were exposed to 30 °C for four weeks (stage 1), 39 °C for six weeks (stage 2) and 30 °C for three weeks (stage 3). Faecal samples were collected from both control and test animals to monitor faecal glucocorticoid metabolite (fGCM) concentrations as a proxy of physiological stress. Although the fGCM levels of control females remained constant, test females showed an acute fGCM increase following the increase and subsequent decrease of temperatures. The test male had significantly higher fGCM levels during stage 3, compared with stage 1 and 2. The control male, although displaying constant fGCM levels throughout the study, had higher fGCM levels than the test male. The results indicate that a considerable temporal increase in environmental temperature did not lead to chronically elevated adrenocortical activity in sungazer lizards. It is likely that inherent traits within the species allow the species to adapt to such changes. Furthermore, the endangered status of the species and limited availability of study animals restricted the sample size in this study to a few, captive-based lizards. Therefore, although our results are an important addition to reptile conservation, they should be extrapolated to free-ranging populations with caution. Future research should consider the effects of chronically elevated temperature in relation to water and food shortages, as well as interindividual variation in physiological responses.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"222 - 230"},"PeriodicalIF":1.1,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43408814","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/15627020.2021.1942204
Maria Granell-Ruiz, K. Norén, D. Kalthoff, A. le Roux, F. Dalerum
Information on genetic variation within and among populations is relevant for a broad range of topics in biology. We use a combination of mitochondrial and nuclear microsatellite markers to evaluate genetic variation within and between two populations of bat-eared foxes (Otocyon megalotis Desmarest, 1822) in South Africa. The bat-eared fox is a small canid occurring in southern and eastern Africa. The species is currently not threatened with extinction, but a lack of information on genetic diversity has been identified as a deficit for its future conservation. We observed low to moderate genetic differentiation between the two geographically separated populations, but neither mitochondrial nor nuclear microsatellite markers suggested that there have been dispersal barriers between them. Similar genetic diversity within both populations was contrasted by interpopulational differences in relatedness variation among males and females. A high genetic relatedness within both populations, indicated by mitochondrial data, is likely caused by a common historical origin or a combination of species-specific social organization and environmental dispersal constraints. We call for further research on the genetic divergence of bat-eared fox populations as well as on the genetic consequences of interactions between environmental characteristics and social organization in this species.
{"title":"Genetic Variation between and within Two Populations of Bat-Eared Foxes (Otocyon megalotis Desmarest, 1822) in South Africa","authors":"Maria Granell-Ruiz, K. Norén, D. Kalthoff, A. le Roux, F. Dalerum","doi":"10.1080/15627020.2021.1942204","DOIUrl":"https://doi.org/10.1080/15627020.2021.1942204","url":null,"abstract":"Information on genetic variation within and among populations is relevant for a broad range of topics in biology. We use a combination of mitochondrial and nuclear microsatellite markers to evaluate genetic variation within and between two populations of bat-eared foxes (Otocyon megalotis Desmarest, 1822) in South Africa. The bat-eared fox is a small canid occurring in southern and eastern Africa. The species is currently not threatened with extinction, but a lack of information on genetic diversity has been identified as a deficit for its future conservation. We observed low to moderate genetic differentiation between the two geographically separated populations, but neither mitochondrial nor nuclear microsatellite markers suggested that there have been dispersal barriers between them. Similar genetic diversity within both populations was contrasted by interpopulational differences in relatedness variation among males and females. A high genetic relatedness within both populations, indicated by mitochondrial data, is likely caused by a common historical origin or a combination of species-specific social organization and environmental dispersal constraints. We call for further research on the genetic divergence of bat-eared fox populations as well as on the genetic consequences of interactions between environmental characteristics and social organization in this species.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"165 - 172"},"PeriodicalIF":1.1,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/15627020.2021.1942204","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46749271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/15627020.2021.1975560
MA Petford, G. Alexander
Measures of activity patterns in relation to environmental conditions provide insights into ecologically driven requirements and climate preferences of species, particularly for ectotherms, due to the strong relationship between body temperature (Tb) and environmental temperatures. Lygodactylus incognitus (cryptic dwarf gecko) and Lygodactylus soutpansbergensis (Soutpansberg dwarf gecko) are range-restricted endemics to the Soutpansberg Mountains, South Africa, and have recently been shown to be potentially vulnerable to the effects of climate change. This prompted us to study the relationship between the thermoregulatory characteristics and environmental temperatures for these syntopic species. Active geckos (i.e. those outside of a refuge) and environmental variables were recorded during scan surveys across two seasons. Binomial logistic regressions were used to predict and explain activity based on presence/absence measures and environmental variables for each species. Of the variables measured, air temperature (Ta) was the main predictor of activity for both species. Cryptic dwarf geckos were active in cooler Ta than warmer temperatures in comparison to Soutpansberg dwarf geckos. Cryptic dwarf geckos are thus well adapted to temperate conditions. Soutpansberg dwarf geckos appear well adapted for warmer conditions, as they were more likely to be active at higher Ta. Our findings suggest that both species will alter their daily activity times in response to changing climate, but that the cryptic dwarf gecko is likely to be more negatively impacted than the Soutpansberg dwarf gecko, due to their affinity for cooler temperatures and avoidance of the hottest temperatures exhibited during the study period. Therefore, although these broadly sympatric, syntopic, range-restricted species are closely related and have similar life histories, they occupy different thermal niches and are likely to respond to climate change idiosyncratically. Our findings caution against the overuse of proxy species in predicting species geographic distribution changes in response to climate change.
{"title":"Diel Activity Patterns of Two Syntopic Range-Restricted Geckos Suggest Idiosyncratic Responses to Climate Change","authors":"MA Petford, G. Alexander","doi":"10.1080/15627020.2021.1975560","DOIUrl":"https://doi.org/10.1080/15627020.2021.1975560","url":null,"abstract":"Measures of activity patterns in relation to environmental conditions provide insights into ecologically driven requirements and climate preferences of species, particularly for ectotherms, due to the strong relationship between body temperature (Tb) and environmental temperatures. Lygodactylus incognitus (cryptic dwarf gecko) and Lygodactylus soutpansbergensis (Soutpansberg dwarf gecko) are range-restricted endemics to the Soutpansberg Mountains, South Africa, and have recently been shown to be potentially vulnerable to the effects of climate change. This prompted us to study the relationship between the thermoregulatory characteristics and environmental temperatures for these syntopic species. Active geckos (i.e. those outside of a refuge) and environmental variables were recorded during scan surveys across two seasons. Binomial logistic regressions were used to predict and explain activity based on presence/absence measures and environmental variables for each species. Of the variables measured, air temperature (Ta) was the main predictor of activity for both species. Cryptic dwarf geckos were active in cooler Ta than warmer temperatures in comparison to Soutpansberg dwarf geckos. Cryptic dwarf geckos are thus well adapted to temperate conditions. Soutpansberg dwarf geckos appear well adapted for warmer conditions, as they were more likely to be active at higher Ta. Our findings suggest that both species will alter their daily activity times in response to changing climate, but that the cryptic dwarf gecko is likely to be more negatively impacted than the Soutpansberg dwarf gecko, due to their affinity for cooler temperatures and avoidance of the hottest temperatures exhibited during the study period. Therefore, although these broadly sympatric, syntopic, range-restricted species are closely related and have similar life histories, they occupy different thermal niches and are likely to respond to climate change idiosyncratically. Our findings caution against the overuse of proxy species in predicting species geographic distribution changes in response to climate change.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"202 - 212"},"PeriodicalIF":1.1,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42740397","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/15627020.2021.1958056
F. Chibwana, Jestina Katandukila
Most migratory aquatic birds are regarded as reservoir hosts for many parasitic diseases, including digenetic trematodes that cause significant losses to farmed fish. However, in Tanzania, studies of birds focus more on their species diversity and patterns of speciation than their parasites. The current study attempted to use molecular methods, mitochondrial DNA (mtDNA), cytochrome c oxidase subunit I (COX-1) in particular, and ribosomal DNA (rDNA) i.e. 28S rRNA and internal transcribed spacer (ITS1-5.8S-ITS2) regions, to investigate the occurrence of intestinal echinostomatoid species recovered from fish-eating birds, i.e. Grey Herons (Ardea cinerea) and Great Cormorants (Phalacrocorax carbo), from Mwanza Gulf in Lake Victoria. Both morphology and molecular markers revealed the presence of three echinostomatoid species: Stephanoprora amurensis and Petasiger phalacrocoracis in P. carbo, and the Patagifer vioscai in A. cinerea. The present species are reported for the first time in African bird species.
{"title":"Occurrence of Echinostomatoids (Platyhelminthes: Digenea) in Great Cormorant (Phalacrocorax carbo) and Grey Heron (Ardea cinerea): First Insights into the DNA Barcodes from Lake Victoria, Tanzania","authors":"F. Chibwana, Jestina Katandukila","doi":"10.1080/15627020.2021.1958056","DOIUrl":"https://doi.org/10.1080/15627020.2021.1958056","url":null,"abstract":"Most migratory aquatic birds are regarded as reservoir hosts for many parasitic diseases, including digenetic trematodes that cause significant losses to farmed fish. However, in Tanzania, studies of birds focus more on their species diversity and patterns of speciation than their parasites. The current study attempted to use molecular methods, mitochondrial DNA (mtDNA), cytochrome c oxidase subunit I (COX-1) in particular, and ribosomal DNA (rDNA) i.e. 28S rRNA and internal transcribed spacer (ITS1-5.8S-ITS2) regions, to investigate the occurrence of intestinal echinostomatoid species recovered from fish-eating birds, i.e. Grey Herons (Ardea cinerea) and Great Cormorants (Phalacrocorax carbo), from Mwanza Gulf in Lake Victoria. Both morphology and molecular markers revealed the presence of three echinostomatoid species: Stephanoprora amurensis and Petasiger phalacrocoracis in P. carbo, and the Patagifer vioscai in A. cinerea. The present species are reported for the first time in African bird species.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"181 - 191"},"PeriodicalIF":1.1,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44683553","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/15627020.2021.1949389
FP Cuozzo, A. Halajian, ML Sauther, KM Rampedi, JB Millette
To date, there have been few published reports of Caracal spp. (or other non-domestic carnivores) preying upon nocturnal strepsirrhine primates anywhere in continental Africa. However, in South Africa, most studies of caracal diet have been conducted outside of the known geographic range of South Africa's nocturnal primates. Here we report Otolemur crassicaudatus (the greater or thick-tailed bushbaby/galago) remains recovered from the stomach of a caracal, collected in Limpopo province, South Africa, in 2018, which included portions of the limbs, tail, skull and dentition, allowing confident taxonomic assignment. Sixty-seven carnivores (equal in size or larger than O. crassicaudatus), including one other caracal, also had stomach contents examined between 2012 and 2019 in northern South Africa. None included O. crassicaudatus remains, making this the first documented example of this non-human primate species being preyed upon by an endemic carnivore; kills of O. crassicaudatus by domestic dogs, though not being consumed, have previously been documented. These data expand the knowledge of the diet of caracal in southern Africa and may signal an expanding caracal dietary regime and possible behavioural changes in O. crassicaudatus, such as increased terrestrial movement, with increasing human actions and reduction of endemic forests and habitats.
{"title":"First Report of the Thick-Tailed Bushbaby (Otolemur crassicaudatus) being Preyed Upon by an Endemic Carnivore (Caracal caracal) in South Africa","authors":"FP Cuozzo, A. Halajian, ML Sauther, KM Rampedi, JB Millette","doi":"10.1080/15627020.2021.1949389","DOIUrl":"https://doi.org/10.1080/15627020.2021.1949389","url":null,"abstract":"To date, there have been few published reports of Caracal spp. (or other non-domestic carnivores) preying upon nocturnal strepsirrhine primates anywhere in continental Africa. However, in South Africa, most studies of caracal diet have been conducted outside of the known geographic range of South Africa's nocturnal primates. Here we report Otolemur crassicaudatus (the greater or thick-tailed bushbaby/galago) remains recovered from the stomach of a caracal, collected in Limpopo province, South Africa, in 2018, which included portions of the limbs, tail, skull and dentition, allowing confident taxonomic assignment. Sixty-seven carnivores (equal in size or larger than O. crassicaudatus), including one other caracal, also had stomach contents examined between 2012 and 2019 in northern South Africa. None included O. crassicaudatus remains, making this the first documented example of this non-human primate species being preyed upon by an endemic carnivore; kills of O. crassicaudatus by domestic dogs, though not being consumed, have previously been documented. These data expand the knowledge of the diet of caracal in southern Africa and may signal an expanding caracal dietary regime and possible behavioural changes in O. crassicaudatus, such as increased terrestrial movement, with increasing human actions and reduction of endemic forests and habitats.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"231 - 235"},"PeriodicalIF":1.1,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/15627020.2021.1949389","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46197682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-07-03DOI: 10.1080/15627020.2021.1962737
T. de Haas, L. Connell, R. Greenfield
Anthropogenic activities have propelled the exploitation of natural environments, which along with climate change have resulted in salinity intrusion to freshwater ecosystems worldwide. To determine the extent the hypersalinity stressor has on freshwater ecosystems, physiological cardiac responses in the freshwater gastropod Melanoides tuberculata were analysed during an acute exposure to varying salinity concentrations. A non-invasive method was used to monitor the cardiac activity of the organisms. The mean heart rate (bpm) of M. tuberculata declined significantly between 20 ppt and 30 ppt. Melanoides tuberculata exhibited a hypersalinity threshold of 25 ppt and tolerated salinity concentrations up to 50 ppt. Data collected provide background data for the use of M. tuberculata as a bioindicator organism to assess the effects of hypersalinity on cardiac response of organisms in a freshwater ecosystem.
{"title":"Investigating the Effects of Hypersalinity on the Cardiac Performance of the Invasive Gastropod Melanoides tuberculata (Müller, 1774)","authors":"T. de Haas, L. Connell, R. Greenfield","doi":"10.1080/15627020.2021.1962737","DOIUrl":"https://doi.org/10.1080/15627020.2021.1962737","url":null,"abstract":"Anthropogenic activities have propelled the exploitation of natural environments, which along with climate change have resulted in salinity intrusion to freshwater ecosystems worldwide. To determine the extent the hypersalinity stressor has on freshwater ecosystems, physiological cardiac responses in the freshwater gastropod Melanoides tuberculata were analysed during an acute exposure to varying salinity concentrations. A non-invasive method was used to monitor the cardiac activity of the organisms. The mean heart rate (bpm) of M. tuberculata declined significantly between 20 ppt and 30 ppt. Melanoides tuberculata exhibited a hypersalinity threshold of 25 ppt and tolerated salinity concentrations up to 50 ppt. Data collected provide background data for the use of M. tuberculata as a bioindicator organism to assess the effects of hypersalinity on cardiac response of organisms in a freshwater ecosystem.","PeriodicalId":55548,"journal":{"name":"African Zoology","volume":"56 1","pages":"192 - 201"},"PeriodicalIF":1.1,"publicationDate":"2021-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47344247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：