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  1. Artikel: Collaboration for conservation: Assessing countrywide carnivore occupancy dynamics from sparse data

    Van der Weyde, Leanne K. / Tobler, Mathias W. / Gielen, Marie Charlotte / Cozzi, Gabriele / Weise, Florian J. / Adams, Tempe / Bauer, Dominik / Bennitt, Emily / Bowles, Matthew / Brassine, Alienor / Broekhuis, Femke / Chase, Michael / Collins, Kai / Finerty, Genevieve E. / Golabek, Krystyna / Hartley, Robyn / Henley, Steve / Isden, Jessica / Keeping, Derek /
    Kesch, Kristina / Klein, Rebecca / Kokole, Morulaganyi / Kotze, Robynne / LeFlore, Eric / Maude, Glyn / McFarlane, Kevin / McNutt, J. Weldon / Mills, Gus / Morapedi, Mompoloi / Morgan, Simon / Ngaka, Keitumetse / Proust, Nicolas / Rich, Lindsey / Roodbal, Marnus / Selebatso, Moses / Snyman, Andrei / Stein, Andrew / Sutcliff, Robert / Tshimologo, Botilo / Whitesell, Carolyn / Winterbach, Christiaan / Flyman, Michael V.

    Diversity & distributions. 2022 May, v. 28, no. 5

    2022  

    Abstract: AIM: Assessing the distribution and persistence of species across their range is a crucial component of wildlife conservation. It demands data at adequate spatial scales and over extended periods of time, which may only be obtained through collaborative ... ...

    Abstract AIM: Assessing the distribution and persistence of species across their range is a crucial component of wildlife conservation. It demands data at adequate spatial scales and over extended periods of time, which may only be obtained through collaborative efforts, and the development of methods that integrate heterogeneous datasets. We aimed to combine existing data on large carnivores to evaluate population dynamics and improve knowledge on their distribution nationwide. LOCATION: Botswana. METHODS: Between 2010 and 2016, we collated data on African wild dog, cheetah, leopard, brown and spotted hyaena and lion gathered with different survey methods by independent researchers across Botswana. We used a multi‐species, multi‐method dynamic occupancy model to analyse factors influencing occupancy, persistence and colonization, while accounting for imperfect detection. Lastly, we used the gained knowledge to predict the probability of occurrence of each species countrywide. RESULTS: Wildlife areas and communal rangelands had similar occupancy probabilities for most species. Large carnivore occupancy was low in commercial farming areas and where livestock density was high, except for brown hyaena. Lion occupancy was negatively associated with human density; lion and spotted hyaena occupancy was high where rainfall was high, while the opposite applied to brown hyaena. Lion and leopard occupancy remained constant countrywide over the study period. African wild dog and cheetah occupancy declined over time in the south and north, respectively, whereas both hyaena species expanded their ranges. Countrywide predictions identified the highest occupancy for leopards and lowest for the two hyaena species. MAIN CONCLUSIONS: We highlight the necessity of data sharing and propose a generalizable analytical method that addresses the challenges of heterogeneous data common in ecology. Our approach, which enables a comprehensive multi‐species assessment at large spatial and temporal scales, supports the development of data‐driven conservation guidelines and the implementation of evidence‐based management strategies nationally and internationally.
    Schlagwörter Acinonyx jubatus ; Hyaena ; Lycaon pictus ; analytical methods ; carnivores ; data collection ; humans ; livestock ; models ; population dynamics ; probability ; rain ; rangelands ; surveys ; wildlife ; wildlife management ; Botswana
    Sprache Englisch
    Erscheinungsverlauf 2022-05
    Umfang p. 917-929.
    Erscheinungsort John Wiley & Sons, Ltd
    Dokumenttyp Artikel
    Anmerkung JOURNAL ARTICLE
    ZDB-ID 2020139-4
    ISSN 1472-4642 ; 1366-9516
    ISSN (online) 1472-4642
    ISSN 1366-9516
    DOI 10.1111/ddi.13386
    Datenquelle NAL Katalog (AGRICOLA)

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  2. Artikel ; Online: Endocrine correlates of musth and the impact of ecological and social factors in free-ranging African elephants (Loxodonta africana).

    Ganswindt, André / Muenscher, Stefanie / Henley, Michelle / Henley, Steve / Heistermann, Michael / Palme, Rupert / Thompson, Peter / Bertschinger, Henk

    Hormones and behavior

    2010  Band 57, Heft 4-5, Seite(n) 506–514

    Abstract: Sexual activity in mature male African elephants is predominantly associated with the occurrence of musth, a state or condition which refers to a set of physical, physiological and behavioral characteristics, including an elevation in androgen levels. ... ...

    Abstract Sexual activity in mature male African elephants is predominantly associated with the occurrence of musth, a state or condition which refers to a set of physical, physiological and behavioral characteristics, including an elevation in androgen levels. Although musth appears to be energetically costly, the degree to which it is associated with changes in adrenal endocrine function (e.g., glucocorticoid output) is still unclear. To investigate the possible effect of musth on adrenocortical function, and the impact of socioecological changes on androgen and glucocorticoid levels, six adult African elephant bulls were followed for 13months in the Kruger National Park, South Africa, and observations and fecal sample collection for endocrine monitoring was carried out about twice weekly. Our data showed that the occurrence of musth was associated with reduced glucocorticoid output, suggesting that musth does not represent a physiological stress mediated by the hypothalamic-pituitary-adrenal axis. This confirms previous findings in captive-housed animals, providing evidence for a suppressive effect of the musth condition on adrenocortical activity. Furthermore, a seasonal effect on androgen and glucocorticoid levels was found, which appears to vary depending on the reproductive status of the animal. The results also indicate a relationship between the presence or absence of social partners and changes in testicular and adrenal endocrine activity. Finally, the data confirm previous findings in captive-housed elephants, that an elevation in androgen concentrations usually occurs before the onset of physical musth signs, and therefore support the idea that the change in androgen levels represents the initial stimulus for the musth condition.
    Mesh-Begriff(e) Androgens/metabolism ; Animals ; Animals, Wild ; Animals, Zoo ; Data Interpretation, Statistical ; Elephants/physiology ; Environment ; Feces/chemistry ; Female ; Glucocorticoids/metabolism ; Male ; Seasons ; Sexual Behavior, Animal/physiology ; Social Environment
    Chemische Substanzen Androgens ; Glucocorticoids
    Sprache Englisch
    Erscheinungsdatum 2010-04
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 214409-8
    ISSN 1095-6867 ; 0018-506X
    ISSN (online) 1095-6867
    ISSN 0018-506X
    DOI 10.1016/j.yhbeh.2010.02.009
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel ; Online: Collaboration for conservation

    Van der Weyde, Leanne K. / Tobler, Mathias W. / Gielen, Marie Charlotte / Cozzi, Gabriele / Weise, Florian J. / Adams, Tempe / Bauer, Dominik / Bennitt, Emily / Bowles, Matthew / Brassine, Alienor / Broekhuis, Femke / Chase, Michael / Collins, Kai / Finerty, Genevieve E. / Golabek, Krystyna / Hartley, Robyn / Henley, Steve / Isden, Jessica / Keeping, Derek /
    Kesch, Kristina / Klein, Rebecca / Kokole, Morulaganyi / Kotze, Robynne / LeFlore, Eric / Maude, Glyn / McFarlane, Kevin / McNutt, J.W. / Mills, Gus / Morapedi, Mompoloi / Morgan, Simon / Ngaka, Keitumetse / Proust, Nicolas / Rich, Lindsey / Roodbal, Marnus / Selebatso, Moses / Snyman, Andrei / Stein, Andrew / Sutcliff, Robert / Tshimologo, Botilo / Whitesell, Carolyn / Winterbach, Christiaan / Flyman, Michael V.

    Diversity and Distributions

    Assessing countrywide carnivore occupancy dynamics from sparse data

    2022  Band 28, Heft 5

    Abstract: Aim: Assessing the distribution and persistence of species across their range is a crucial component of wildlife conservation. It demands data at adequate spatial scales and over extended periods of time, which may only be obtained through collaborative ... ...

    Abstract Aim: Assessing the distribution and persistence of species across their range is a crucial component of wildlife conservation. It demands data at adequate spatial scales and over extended periods of time, which may only be obtained through collaborative efforts, and the development of methods that integrate heterogeneous datasets. We aimed to combine existing data on large carnivores to evaluate population dynamics and improve knowledge on their distribution nationwide. Location: Botswana. Methods: Between 2010 and 2016, we collated data on African wild dog, cheetah, leopard, brown and spotted hyaena and lion gathered with different survey methods by independent researchers across Botswana. We used a multi-species, multi-method dynamic occupancy model to analyse factors influencing occupancy, persistence and colonization, while accounting for imperfect detection. Lastly, we used the gained knowledge to predict the probability of occurrence of each species countrywide. Results: Wildlife areas and communal rangelands had similar occupancy probabilities for most species. Large carnivore occupancy was low in commercial farming areas and where livestock density was high, except for brown hyaena. Lion occupancy was negatively associated with human density; lion and spotted hyaena occupancy was high where rainfall was high, while the opposite applied to brown hyaena. Lion and leopard occupancy remained constant countrywide over the study period. African wild dog and cheetah occupancy declined over time in the south and north, respectively, whereas both hyaena species expanded their ranges. Countrywide predictions identified the highest occupancy for leopards and lowest for the two hyaena species. Main Conclusions: We highlight the necessity of data sharing and propose a generalizable analytical method that addresses the challenges of heterogeneous data common in ecology. Our approach, which enables a comprehensive multi-species assessment at large spatial and temporal scales, supports the development of data-driven ...
    Schlagwörter Botswana ; data sharing ; distribution ; human-dominated landscapes ; imperfect detection ; management ; protected areas
    Thema/Rubrik (Code) 333
    Sprache Englisch
    Erscheinungsland nl
    Dokumenttyp Artikel ; Online
    ZDB-ID 2020139-4
    ISSN 1472-4642 ; 1366-9516
    ISSN (online) 1472-4642
    ISSN 1366-9516
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  4. Artikel: The spatial scaling of habitat selection by African elephants

    De Knegt, Henrik J / Van Langevelde, Frank / Skidmore, Andrew K / Delsink, Audrey / Slotow, Rob / Henley, Steve / Bucini, Gabriela / De Boer, Willem F / Coughenour, Michael B / Grant, Cornelia C / Heitkönig, Ignas M.A / Henley, Michelle / Knox, Nicky M / Kohi, Edward M / Mwakiwa, Emmanuel / Page, Bruce R / Peel, Mike / Pretorius, Yolanda / Van Wieren, Sipke E /
    Prins, Herbert H.T

    Journal of animal ecology. 2011 Jan., v. 80, no. 1

    2011  

    Abstract: 1. Understanding and accurately predicting the spatial patterns of habitat use by organisms is important for ecological research, biodiversity conservation and ecosystem management. However, this understanding is complicated by the effects of spatial ... ...

    Abstract 1. Understanding and accurately predicting the spatial patterns of habitat use by organisms is important for ecological research, biodiversity conservation and ecosystem management. However, this understanding is complicated by the effects of spatial scale, because the scale of analysis affects the quantification of species-environment relationships. 2. We therefore assessed the influence of environmental context (i.e. the characteristics of the landscape surrounding a site), varied over a large range of scales (i.e. ambit radii around focal sites), on the analysis and prediction of habitat selection by African elephants in Kruger National Park, South Africa. 3. We focused on the spatial scaling of the elephants' response to their main resources, forage and water, and found that the quantification of habitat selection strongly depended on the scales at which environmental context was considered. Moreover, the inclusion of environmental context at characteristic scales (i.e. those at which habitat selectivity was maximized) increased the predictive capacity of habitat suitability models. 4. The elephants responded to their environment in a scale-dependent and perhaps hierarchical manner, with forage characteristics driving habitat selection at coarse spatial scales, and surface water at fine spatial scales. 5. Furthermore, the elephants exhibited sexual habitat segregation, mainly in relation to vegetation characteristics. Male elephants preferred areas with high tree cover and low herbaceous biomass, whereas this pattern was reversed for female elephants. 6. We show that the spatial distribution of elephants can be better understood and predicted when scale-dependent species-environment relationships are explicitly considered. This demonstrates the importance of considering the influence of spatial scale on the analysis of spatial patterning in ecological phenomena.
    Schlagwörter Loxodonta africana ; biodiversity ; biomass ; ecosystem management ; forage ; habitats ; landscapes ; models ; national parks ; prediction ; surface water ; trees ; vegetation ; South Africa
    Sprache Englisch
    Erscheinungsverlauf 2011-01
    Umfang p. 270-281.
    Erscheinungsort Blackwell Publishing Ltd
    Dokumenttyp Artikel
    ZDB-ID 3024-7
    ISSN 1365-2656 ; 0021-8790
    ISSN (online) 1365-2656
    ISSN 0021-8790
    DOI 10.1111/j.1365-2656.2010.01764.x
    Datenquelle NAL Katalog (AGRICOLA)

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  5. Artikel ; Online: The spatial scaling of habitat selection by African elephants.

    de Knegt, Henrik J / van Langevelde, Frank / Skidmore, Andrew K / Delsink, Audrey / Slotow, Rob / Henley, Steve / Bucini, Gabriela / de Boer, Willem F / Coughenour, Michael B / Grant, Cornelia C / Heitkönig, Ignas M A / Henley, Michelle / Knox, Nicky M / Kohi, Edward M / Mwakiwa, Emmanuel / Page, Bruce R / Peel, Mike / Pretorius, Yolanda / van Wieren, Sipke E /
    Prins, Herbert H T

    The Journal of animal ecology

    2011  Band 80, Heft 1, Seite(n) 270–281

    Abstract: 1. Understanding and accurately predicting the spatial patterns of habitat use by organisms is important for ecological research, biodiversity conservation and ecosystem management. However, this understanding is complicated by the effects of spatial ... ...

    Abstract 1. Understanding and accurately predicting the spatial patterns of habitat use by organisms is important for ecological research, biodiversity conservation and ecosystem management. However, this understanding is complicated by the effects of spatial scale, because the scale of analysis affects the quantification of species-environment relationships. 2. We therefore assessed the influence of environmental context (i.e. the characteristics of the landscape surrounding a site), varied over a large range of scales (i.e. ambit radii around focal sites), on the analysis and prediction of habitat selection by African elephants in Kruger National Park, South Africa. 3. We focused on the spatial scaling of the elephants' response to their main resources, forage and water, and found that the quantification of habitat selection strongly depended on the scales at which environmental context was considered. Moreover, the inclusion of environmental context at characteristic scales (i.e. those at which habitat selectivity was maximized) increased the predictive capacity of habitat suitability models. 4. The elephants responded to their environment in a scale-dependent and perhaps hierarchical manner, with forage characteristics driving habitat selection at coarse spatial scales, and surface water at fine spatial scales. 5. Furthermore, the elephants exhibited sexual habitat segregation, mainly in relation to vegetation characteristics. Male elephants preferred areas with high tree cover and low herbaceous biomass, whereas this pattern was reversed for female elephants. 6. We show that the spatial distribution of elephants can be better understood and predicted when scale-dependent species-environment relationships are explicitly considered. This demonstrates the importance of considering the influence of spatial scale on the analysis of spatial patterning in ecological phenomena.
    Mesh-Begriff(e) Animals ; Demography ; Ecosystem ; Elephants/physiology ; Female ; Male ; Models, Biological ; South Africa
    Sprache Englisch
    Erscheinungsdatum 2011-01
    Erscheinungsland England
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3024-7
    ISSN 1365-2656 ; 0021-8790
    ISSN (online) 1365-2656
    ISSN 0021-8790
    DOI 10.1111/j.1365-2656.2010.01764.x
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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