The diving behavior of African clawless and spotted-necked otters in freshwater environments DOI Open Access
Rowan K. Jordaan,

Michael J. Somers,

Trevor McIntyre

et al.

Journal of Mammalogy, Journal Year: 2021, Volume and Issue: 102(4), P. 1020 - 1029

Published: Feb. 25, 2021

Abstract Understanding the diving behavior of semiaquatic mammals, particularly in relation to estimated aerobic dive limits and diet, is important understand their adaptability potential vulnerability changes prey type distribution. The African clawless otters, Aonyx capensis, spotted-necked Hydrictis maculicollis, poorly known, no estimates performance targeted calculated have been reported previously for freshwater environments. We investigated both these otter species environments within South Africa through video recordings direct observations subsequent analyses where recovery durations function were recorded. otters found perform longer dives (mean ± SD = 26.9 12.2 s), compared (8.5 7.6 s). showed substantial variation durations, with shortest sometimes lasting < 5 s, longest recorded being 70 s. majority lasted 10 0.66 s 50.9 Spotted-necked performed different types that evidently dependent on targeted, targeting crabs (16.10 1.91 s) than rainbow trout, Oncorhynchus mykiss (5.58 0.17 theoretical exceeded during play dives, while when performing successful foraging dives. results this study suggest can vary exceed duration maximize net rate energy gain. Furthermore, considering known individual-level dietary specialization plasticity species, it may be predicted behaviors are likely substantially among individuals, availability localized habitat conditions.

Language: Английский

Camera trap-based estimates reveal spatial variability in African clawless otter population densities and behaviour DOI Creative Commons
Candice B. Lewis, Tshepiso L. Majelantle, Natalie S. Haussmann

et al.

Oryx, Journal Year: 2025, Volume and Issue: unknown, P. 1 - 14

Published: Feb. 21, 2025

Abstract Estimating the population size of shy and elusive species is challenging but necessary to inform appropriate conservation actions for threatened or declining species. Using camera-trap surveys conducted during 2017–2021, we estimated compared African clawless otter Aonyx capensis densities activity times in six conserved areas southern Africa. We used two different models estimate densities: random encounter distance sampling. Our results highlight a general pattern higher narrower confidence intervals using found substantial variation between study areas, with model estimates ranging 0.9 4.2 otters/km 2 . sampling supported relative density obtained from were generally lower more variable, 0.8 4.0 significant differences patterns, populations either being nocturnal, mostly nocturnal cathemeral. As all experience little human disturbance, our suggest that there are large natural variations patterns regions. When converted metrics comparable previous studies, numbers than previously reported. This highlights need broader spatial coverage assessments future studies assess potential environmental drivers spatial, potentially temporal, patterns.

Language: Английский

Citations

0
Spraint density of the Eurasian otter (Lutra lutra) is an accurate indicator of its population status in urban areas. DOI Creative Commons

Jooseong Kim,

Sungwon Hong

Environmental and Sustainability Indicators, Journal Year: 2024, Volume and Issue: unknown, P. 100479 - 100479

Published: Sept. 1, 2024

Language: Английский

Citations

2
Faecal glucocorticoid metabolite levels of intensive captive, free‐range captive and wild Tasmanian devils DOI Creative Commons
Stevie N. Florent,

Judy Clarke,

Meredith J. Bashaw

et al.

Journal of Zoology, Journal Year: 2023, Volume and Issue: 320(4), P. 282 - 291

Published: June 5, 2023

Abstract Captivity can alter the stress physiology and behaviour of an animal in both short‐ long‐term through repetitive exposure to novel stressors and, subsequently, may reduce success conservation efforts such as translocation reintroduction. The Tasmanian devil ( Sarcophilus harrisii ) is threatened with extinction from a fatal facial tumour disease which has led establishment insurance meta‐population designed for future reintroductions disease‐free devils. comprised intensive captive free‐range environments; however, no study yet examined physiological implications captivity on We used non‐invasive faecal glucocorticoid metabolite (FGM) monitoring determine if there were any differences adrenal activity among captive, wild FGM levels not age or sex dependent, we found that all population types had similar intra‐population variability mean FGMs. In conclusion, environment appear maintain profiles

Language: Английский

Citations

1
Stakeholder perceptions of human–predator conflict in the South African fly‐fishing industry DOI Creative Commons

Marié de Vos,

Trevor McIntyre

African Journal of Ecology, Journal Year: 2023, Volume and Issue: 62(1)

Published: June 26, 2023

Abstract Human–wildlife conflict in African aquaculture and fisheries is poorly understood. We investigated this through a questionnaire aimed at owners managers of fly‐fishing properties South Africa. While perceptions losses varied, all respondents reported to predators. Resulting mitigation measures, including lethal control, were employed mostly against cormorants ( Phalacrocorax spp.) otters Aonyx capensis Hydrictis maculicollis ). Given that potentially provide valuable habitat for protected species such as otters, our results highlight need improved measures exploring alternative options generating income from tourism associated with the presence charismatic

Language: Английский

Citations

1
Phylogeny is a stronger predictor of activity than allometry in an African mammal community DOI
Herbert Kasozi, Remington J. Moll, Robert Kityo

et al.

Biological Journal of the Linnean Society, Journal Year: 2021, Volume and Issue: 135(3), P. 599 - 609

Published: Nov. 26, 2021

Abstract In promoting coexistence, sympatric species often partition shared resources along spatio-temporal domains. Similarly sized and phylogenetically close species, for instance, the times of day in which they are active to limit interference competition. Given that variation body mass has evolutionary underpinnings, activity levels (time spent a 24-h daily cycle) within animal communities might be structured by phylogeny. However, few studies have tested this hypothesis across communities, none among medium-sized large mammals. We quantified relative contributions phylogeny predicting community 22 mammal Murchison Falls National Park, Uganda. show is stronger predictor than mass. Our findings provide empirical evidence phylogenetic structuring diverse communities. More broadly, our results suggest relationships mask allometry traits

Language: Английский

Citations

3
The diving behavior of African clawless and spotted-necked otters in freshwater environments DOI Open Access
Rowan K. Jordaan,

Michael J. Somers,

Trevor McIntyre

et al.

Journal of Mammalogy, Journal Year: 2021, Volume and Issue: 102(4), P. 1020 - 1029

Published: Feb. 25, 2021

Abstract Understanding the diving behavior of semiaquatic mammals, particularly in relation to estimated aerobic dive limits and diet, is important understand their adaptability potential vulnerability changes prey type distribution. The African clawless otters, Aonyx capensis, spotted-necked Hydrictis maculicollis, poorly known, no estimates performance targeted calculated have been reported previously for freshwater environments. We investigated both these otter species environments within South Africa through video recordings direct observations subsequent analyses where recovery durations function were recorded. otters found perform longer dives (mean ± SD = 26.9 12.2 s), compared (8.5 7.6 s). showed substantial variation durations, with shortest sometimes lasting < 5 s, longest recorded being 70 s. majority lasted 10 0.66 s 50.9 Spotted-necked performed different types that evidently dependent on targeted, targeting crabs (16.10 1.91 s) than rainbow trout, Oncorhynchus mykiss (5.58 0.17 theoretical exceeded during play dives, while when performing successful foraging dives. results this study suggest can vary exceed duration maximize net rate energy gain. Furthermore, considering known individual-level dietary specialization plasticity species, it may be predicted behaviors are likely substantially among individuals, availability localized habitat conditions.

Language: Английский

Citations

2