114 research outputs found

    The effect of anthropogenic noise and weather conditions on male calls in the bladder grasshopper Bullacris unicolor

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    Acoustic communication in animals relies upon specificcontextsandenvironments for effective signal transmission. Increasing anthropo-genic noise pollution and different weather conditions can disruptacoustic communication. In this study, we investigated call parameterdifferences in the bladder grasshopperBullacris unicolorinhabitingtwo sites in close proximity to each other that differed in their noiselevels. Calling activity was monitored via passive acoustic recorders.Weather conditions, including wind speed, temperature and humid-ity, were also recorded. We found that the interval between succes-sive calls increased with higher noise levels at both sites, and the peakfrequency became lower. The total number of calls detected alsodecreased with anthropogenic noise, but this relationship was onlyevident at the noisier site. In addition, grasshoppers shifted the timingof their calls to later in the night at the noisier site, possibly to takeadvantage of relatively lower noise levels

    The diurnal activity budgets of extralimital giraffe (Giraffa camelopardalis giraffa) in the Western Cape Province, South Africa

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    Despite being an extralimital species in the region, South African giraffes (Giraffa camelopardalis giraffa, Schreber 1784) are continuously being introduced into the Albany Thicket Biome of the Western Cape Province of South Africa. This study aimed to determine the diurnal activity budgets of two extralimital giraffe populations in the Western Cape of South Africa. Diurnal activity budgets are important to provide baseline information on the adaptability of species in newly introduced areas and for more detailed ecological studies such as those relating to habitat suitability, animal–plant interactions and interactions with other resident animals

    Phylogeographic investigation of the bladder grasshopper Bullacris unicolor (Orthoptera Pneumoroidea) in South Africa

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    There are several factors, such as genetic drift, gene flow and migration that affect the population genetic structure and phylogeographic distribution of genetic lineages within single species. Previous studies of the bladder grasshoppers, Bullacris unicolor of South Africa, showed divergence in mitochondrial CO1 (cytochrome c oxidase subunit 1) haplotype diversity and significant genetic structure. In this study, we revisit these findings adding more samples from different locations and using mitochondrial CO1 and Internal transcribed spacer (ITS) gene sequences. We tested the hypothesis that the western, northern and eastern distribution ranges of B. unicolor show different population genetic patterns, corresponding with isolation-by-distance. Mitochondrial CO1 and ITS data were collected for 99 individuals from 12 localities across the Western, Northern and Eastern sides of South Africa. Overall, significant variation in genetic structure was found across the localities as indicated by FST analyses

    TRE-FX:Delivering a federated network of trusted research environments to enable safe data analytics

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    Trusted Research Environments (TREs) are secure locations in which data are placed for researchers to analyse. TREs host administrative data, hospital data or any other data that needs to remain securely isolated, but it is hard for a researcher to perform an analysis across multiple TREs, requesting and gathering the outputs from each one. This is a common problem in the UK's devolved healthcare system of geographical and governance boundaries. There are different ways of implementing TREs and the analysis tools that use them. A solution must be straightforward for existing, independent systems to adopt, must cope with the variety of system implementations, and must work within the "Five Safes" framework that enables data services to provide safe research access to data. TRE-FX assembled leading infrastructure researchers, analysis tool makers, TRE providers and public engagement specialists to streamline the exchange of data requests and results. The "Five Safes RO-Crate" standard packages up (Crates) the Objects needed for Research requests and results with the information needed for the tools and TRE providers to ensure that the crates are reviewed and processed according to Five Safes principles. TRE-FX showed how this works using software components and an end-to-end demonstrator implemented by a TRE in Wales. Two other TREs, in Scotland and England, are preparing to follow suit. Two analysis tool providers (Bitfount and DataSHIELD) modified their systems to use the RO-Crates. The next step is practical implementation as part of the HDR UK programme. Two large European projects will develop the approach further. TRE-FX shows that it is possible to streamline how analysis tools access multiple TREs while enabling the TREs to ensure that the access is safe. The approach scales as more TREs are added and can be adopted by established systems. Researchers will then be able to perform an analysis across multiple TREs much more easily, widening the scope of their research and making more effective use of the UK's data. If we had had this for COVID-19 data analysis, it would have super-charged researchers to be able to quickly answer pressing questions across the UK. This work was funded by UK Research & Innovation [Grant Number MC_PC_23007] as part of Phase 1 of the DARE UK (Data and Analytics Research Environments UK) programme, delivered in partnership with Health Data Research UK (HDR UK) and Administrative Data Research UK (ADR UK)

    Assessment of leopard translocations in South Africa

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    DATA AVAILABILITY STATEMENT : The original contributions presented in the study are included in the article/supplementary material. Further inquiries can be directed to the corresponding author.Translocations are commonly employed to mitigate human–carnivore conflict but rarely evaluated, resulting in conflicting reports of success, particularly for leopards (Panthera pardus). We evaluate the status of available leopard translocation data, the factors driving the intentional removal of leopards, and the potential causal factors associated with successful and failed translocation events. We obtained data on 60 leopard translocation events across five provinces in South Africa between 1994 and 2021. We considered a successful translocation outcome when (1) the animal was moved outside of its original home range, (2) the animal established a newhome range away fromthe capture site, (3) no substantive livestock losses were linked to the translocated animal in the post-releasemonitoring period, and (4) the animal survived at least 6months post-translocation. Ifmortality occurred due to factors that were equally likely to impact resident individuals and were unrelated to the translocation event (e.g., poaching), the event was not considered a failed effort. Most translocations were the result of human–carnivore conflict (HCC; 82%, n = 49), stressing the high prevalence of HCC and the importance of advocating preventative conflict mitigation efforts to conserve leopards. The leopards were moved distances from 2.5 to 196.3 km (63.3 ± 51.7km). Forty (67%) translocation events had unknown outcomes, indicating the limited data available on translocation outcomes. This also indicates the disparity in the objectives of translocations by various entities involved with translocations and suggests that monitoring be a prerequisite for future translocations. Twenty events offered reliable outcomes by means of post-event monitoring, with seven (12%) considered successful, with three (5%) as failures, and with four (7%) not moved beyond their original home ranges, while six (8%) ended in unrelated deaths. The failed events were attributed to inter/intra-specific competition, and one animal returned to its original home range after a translocation distance of 68 km. Translocation success was strongly explained by translocation distance. We found that damage-causing leopards were successfully translocated under specific conditions, and longer translocation distances increase success. Translocations are commonly employed but are still poorlymonitored.We discuss basic standardized protocols to improve future leopard translocations (including pre- and post-monitoring) while advocating alternative non-lethal practices to reduce the prevalence of human–carnivore conflict.Hans Hoheisen Conservation Trust, Mary Oppenheimer and Daughters Foundation, National Department of Forestry, Fisheries and Environment, Development Bank of Southern Africa, Global Environmental Facility project managed by the United Nations Environmental Program: GEF Project identity number: 9382; Umoja No. 01333, Green Fund, United Nations Environmental Program, United Nations Development Program, GEF Small Grants Programme, National Lotteries Distribution Trust Fund, now called National Lotteries Commission, Project Number 73027, Landmark Foundation Trust, Henry and Iris Englund Foundation, Abax Foundation, Mones Michaels Trust, Felix Schneier Foundation, JDI, Brad Banducci and Arne Hanson.https://www.frontiersin.org/journals/conservation-scienceam2023Centre for Wildlife Managemen

    Genetic Approaches To The Analysis of Body Colouration in Nile Tilapia (Oreochromis niloticus)

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    Body colouration in tilapia is an important trait affecting consumer preference. In the Nile tilapia (Oreochromis niloticus), there are three colour variants which are normal (wild type), red and blond. In some countries, the red variant is important and reaches higher prices in the market. However, one major problem regarding red tilapia culture is their body colouration which is often associated with blotching (mainly black but also red) which is undesirable for the consumer. The overall aim of this work was to expand knowledge on various aspects of body colouration in Nile tilapia using genetic approaches. The results of this research are presented as four different manuscripts. The manuscripts (here referred as Papers) have either been published (Paper IV) or are to be submitted (Paper I, II and III) in relevant peer reviewed journals. Paper I and II investigated the inheritance of black blotching and other body colour components of the red body colour. Specifically, Paper I consisted of two preliminary trials (Trial 1 and 2), to look at the ontogeny of black blotching and body colour components over a period of six months. Trial 1 investigated the effect of tank background colour (light vs dark) on black blotching and other body colour components and was carried out using a fully inbred (all female) clonal red line. Trial 2 was carried out using mixed sex fish and was aimed to investigate the association of black blotching with the sex of the fish. The results from this study were used to guide the experiment described in Paper II. Sixteen red sires with various levels of black and red blotching were crossed to clonal females and the inheritance of blotching and other body colour components were investigated using parent-offspring regressions. The results showed no significant heritability for black blotching and body redness, but a significant correlation for body redness and black blotching was found in female offspring at one sampling point suggesting that attempts to increase body redness may increase black blotching, as had been hypothesized. Paper III was divided into two parts. The first objective was to map the blond locus onto the tilapia linkage map and the second was to investigate the interaction of the blond and red genes on black blotching using the blond-linked markers to distinguish different blond genotypes in heterozygous red fish (i.e. RrBlbl or Rrblbl). In the blond fish, the formation of melanin is almost blocked via much reduced melanophores and this feature may be able to help reducing the black blotching in red tilapia. Two intraspecific families (O. niloticus) and one interspecific family (O. aureus and O. niloticus) were used as mapping families and the blond locus was located in LG5. Four out of eight markers were successfully used to assess the interaction of blond on red blotched fish. The blond gene did not significantly reduce the area of blotching but did reduce the saturation (paler blotching) and enhanced the redness of body colour in the Rrblbl fish compared to the RrBlbl group. Finally, Paper IV aimed to find out the effect of male colouration on reproductive success in Nile tilapia. A choice of one wild type male and one red male was presented to red or wild type females and these fish were allowed to spawn under semi-natural spawning conditions. Eggs were collected from the female’s mouth after spawning and paternity was assessed using microsatellite genotyping and phenotype scoring. No significant departures from equal mating success were observed between the red and wild type males, however there was a significant difference between the red and wild type females in the frequency of secondary paternal contribution to egg batches. The results suggest that mating success of wild type and red tilapia is approximately equal. The results from this research help to broaden our knowledge and understanding on the aspects of body colouration in Nile tilapia and provide fundamental information for further research

    Assessment of leopard translocations in South Africa

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    Translocations are commonly employed to mitigate human–carnivore conflict but rarely evaluated, resulting in conflicting reports of success, particularly for leopards (Panthera pardus). We evaluate the status of available leopard translocation data, the factors driving the intentional removal of leopards, and the potential causal factors associated with successful and failed translocation events. We obtained data on 60 leopard translocation events across five provinces in South Africa between 1994 and 2021. We considered a successful translocation outcome when (1) the animal was moved outside of its original home range, (2) the animal established a new home range away from the capture site, (3) no substantive livestock losses were linked to the translocated animal in the post-release monitoring period, and (4) the animal survived at least 6 months post-translocation. If mortality occurred due to factors that were equally likely to impact resident individuals and were unrelated to the translocation event (e.g., poaching), the event was not considered a failed effort. Most translocations were the result of human–carnivore conflict (HCC; 82%, n = 49), stressing the high prevalence of HCC and the importance of advocating preventative conflict mitigation efforts to conserve leopards. The leopards were moved distances from 2.5 to 196.3 km (63.3 ± 51.7km). Forty (67%) translocation events had unknown outcomes, indicating the limited data available on translocation outcomes. This also indicates the disparity in the objectives of translocations by various entities involved with translocations and suggests that monitoring be a prerequisite for future translocations. Twenty events offered reliable outcomes by means of post-event monitoring, with seven (12%) considered successful, with three (5%) as failures, and with four (7%) not moved beyond their original home ranges, while six (8%) ended in unrelated deaths. The failed events were attributed to inter/intra-specific competition, and one animal returned to its original home range after a translocation distance of 68 km. Translocation success was strongly explained by translocation distance. We found that damage-causing leopards were successfully translocated under specific conditions, and longer translocation distances increase success. Translocations are commonly employed but are still poorly monitored. We discuss basic standardized protocols to improve future leopard translocations (including pre- and post-monitoring) while advocating alternative non-lethal practices to reduce the prevalence of human–carnivore conflict

    Female preference for blue in Japan blue guppies (Poecilia reticulata)

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    Guppies (Poecilia reticulata) are widely used as a model species in mate choice studies. Although native to South America, guppies have been introduced to natural water bodies in disparate regions of the globe. Here, for the first time, we examine guppies from one such introduced population in Japan where males have evolved a predominantly blue color pattern. Previous studies of wild-type guppies have shown blue to play a relatively minor role in the mate choice decisions of females compared to other traits, such as orange, and the importance of blue is not universally supported by all studies. The Japanese population therefore presents an ideal opportunity to re-examine the potential significance of blue as a mate choice cue in guppies. Mate choice experiments, in which female Japan blue guppies were given a choice between pairs of males that differed in their area of blue coloration but were matched for other traits, revealed that females prefer males with proportionately larger amounts of blue in their color patterns. We discuss possible factors, including sexual and ecological selection, which may have led to the evolution of unusually large areas of blue at the expense of other colors in Japan blue guppies. However, further studies are needed to distinguish between these scenarios.Web of Scienc

    The Function of Anal Fin Egg-Spots in the Cichlid Fish Astatotilapia burtoni

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    Color and pigmentation patterns of animals are often targets of sexual selection because of their role in communication. Although conspicuous male traits are typically implicated with intersexual selection, there are examples where sex-specific displays play a role in an intrasexual context, e.g. when they serve as signals for aggression level and/or status. Here, we focus on the function of a conspicuous male ornament in the most species-rich tribe of cichlid fishes, the haplochromines. A characteristic feature of these ca. 1500 species are so-called egg-spots in form of ovoid markings on the anal fins of males, which are made up of carotenoid based pigment cells. It has long been assumed that these yellow, orange or reddish egg-spots play an important role in the courtship and spawning behavior of these maternal mouth-brooding fishes by mimicking the eggs of a conspecific female. The exact function of egg-spots remains unknown, however, and there are several hypotheses about their mode of action. To uncover the function of this cichlid-specific male ornament, we used female mate choice experiments and a male aggression test in the haplochromine species Astatotilapia burtoni. We manipulated the number and arrangement of egg-spots on the anal fins of males, or removed them entirely, and tested (1) female preference with visual contact only using egg-traps, (2) female preference with free contact using paternity testing with microsatellites and (3) male aggression. We found that females did not prefer males with many egg-spots over males with fewer egg-spots and that females tended to prefer males without egg-spots over males with egg-spots. Importantly, males without egg-spots sired clutches with the same fertilization rate as males with egg-spots. In male aggression trials, however, males with fewer egg-spots received significantly more attacks, suggesting that egg-spots are an important signal in intrasexual communication
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