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Bardales R, Boron V, Passos Viana DF, Sousa LL, Dröge E, Porfirio G, Jaramillo M, Payán E, Sillero-Zubiri C, Hyde M. Neotropical mammal responses to megafires in the Brazilian Pantanal. GLOBAL CHANGE BIOLOGY 2024; 30:e17278. [PMID: 38655695 DOI: 10.1111/gcb.17278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 03/19/2024] [Accepted: 03/21/2024] [Indexed: 04/26/2024]
Abstract
The increasing frequency and severity of human-caused fires likely have deleterious effects on species distribution and persistence. In 2020, megafires in the Brazilian Pantanal burned 43% of the biome's unburned area and resulted in mass mortality of wildlife. We investigated changes in habitat use or occupancy for an assemblage of eight mammal species in Serra do Amolar, Brazil, following the 2020 fires using a pre- and post-fire camera trap dataset. Additionally, we estimated the density for two naturally marked species, jaguars Panthera onca and ocelots Leopardus pardalis. Of the eight species, six (ocelots, collared peccaries Dicotyles tajacu, giant armadillos Priodontes maximus, Azara's agouti Dasyprocta azarae, red brocket deer Mazama americana, and tapirs Tapirus terrestris) had declining occupancy following fires, and one had stable habitat use (pumas Puma concolor). Giant armadillo experienced the most precipitous decline in occupancy from 0.431 ± 0.171 to 0.077 ± 0.044 after the fires. Jaguars were the only species with increasing habitat use, from 0.393 ± 0.127 to 0.753 ± 0.085. Jaguar density remained stable across years (2.8 ± 1.3, 3.7 ± 1.3, 2.6 ± 0.85/100 km2), while ocelot density increased from 13.9 ± 3.2 to 16.1 ± 5.2/100 km2. However, the low number of both jaguars and ocelots recaptured after the fire period suggests that immigration may have sustained the population. Our results indicate that the megafires will have significant consequences for species occupancy and fitness in fire-affected areas. The scale of megafires may inhibit successful recolonization, thus wider studies are needed to investigate population trends.
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Affiliation(s)
- Rocío Bardales
- Wildlife Conservation Research Unit, Department of Biology, The Recanati-Kaplan Centre, University of Oxford, Abingdon, UK
- Panthera Cooperation, New York, New York, USA
| | - Valeria Boron
- Panthera Cooperation, New York, New York, USA
- The Living Planet Centre, World Wide Fund for Nature (WWF) UK, Woking, Surrey, UK
| | | | - Lara L Sousa
- Wildlife Conservation Research Unit, Department of Biology, The Recanati-Kaplan Centre, University of Oxford, Abingdon, UK
| | - Egil Dröge
- Wildlife Conservation Research Unit, Department of Biology, The Recanati-Kaplan Centre, University of Oxford, Abingdon, UK
- Zambian Carnivore Programme, Mfuwe, Zambia
| | | | | | - Esteban Payán
- Panthera Cooperation, New York, New York, USA
- Wildlife Conservation Society, New York, New York, USA
| | - Claudio Sillero-Zubiri
- Wildlife Conservation Research Unit, Department of Biology, The Recanati-Kaplan Centre, University of Oxford, Abingdon, UK
| | - Matthew Hyde
- Panthera Cooperation, New York, New York, USA
- Graduate Degree Program in Ecology, Center for Human-Carnivore Coexistence, Colorado State University, Fort Collins, Colorado, USA
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McLean D, Goldingay R, Letnic M. Diet of the Dingo in Subtropical Australian Forests: Are Small, Threatened Macropods at Risk? Animals (Basel) 2023; 13:2257. [PMID: 37508035 PMCID: PMC10376500 DOI: 10.3390/ani13142257] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 06/14/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023] Open
Abstract
Carnivores fulfil important ecological roles in natural systems yet can also jeopardise the persistence of threatened species. Understanding their diet is, therefore, essential for managing populations of carnivores, as well as those of their prey. This study was designed to better understand the diet of an Australian apex predator, the dingo, and determine whether it poses a threat to at-risk small macropods in two floristically different yet geographically close reserves in subtropical Australia. Based on an analysis of 512 scats, dingo diets comprised 34 different prey taxa, of which 50% were common between reserves. Our findings add support to the paradigm that dingoes are opportunistic and generalist predators that prey primarily on abundant mammalian fauna. Their diets in the Border Ranges were dominated by possum species (frequency of occurrence (FOC) = 92.5%), while their diets in Richmond Range were characterised by a high prevalence of pademelon species (FOC = 46.9%). Medium-sized mammals were the most important dietary items in both reserves and across all seasons. The dietary frequency of medium-sized mammals was generally related to their availability (indexed by camera trapping); however, the avoidance of some species with high availability indicates that prey accessibility may also be important in dictating their dietary choices. Other prey categories were supplementary to diets and varied in importance according to seasonal changes in their availability. The diets included two threatened macropods, the red-legged pademelon and black-striped wallaby. Our availability estimates, together with earlier dietary studies spanning 30 years, suggest that the red-legged pademelon is resilient to the observed predation. The black-striped wallaby occurred in only two dingo scats collected from Richmond Range and was not detected by cameras so the threat to this species could not be determined. Two locally abundant but highly threatened species (the koala and long-nosed potoroo) were not detected in the dingoes' diets, suggesting dingoes do not at present pose a threat to these populations. Our study highlights the importance of site-based assessments, population monitoring and including data on prey availability in dietary investigations.
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Affiliation(s)
- Dusty McLean
- Faculty of Science and Engineering, Southern Cross University, Lismore, NSW 2480, Australia
| | - Ross Goldingay
- Faculty of Science and Engineering, Southern Cross University, Lismore, NSW 2480, Australia
| | - Mike Letnic
- Centre for Ecosystem Science, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW 2052, Australia
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Freund DR, Gable TD, Johnson-Bice SM, Homkes AT, Windels SK, Bump JK. The ethology of wolves foraging on freshwater fish in a boreal ecosystem. ROYAL SOCIETY OPEN SCIENCE 2023; 10:230210. [PMID: 37234502 PMCID: PMC10206451 DOI: 10.1098/rsos.230210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 05/05/2023] [Indexed: 05/28/2023]
Abstract
Through global positioning system (GPS) collar locations, remote cameras, field observations and the first wild wolf to be GPS-collared with a camera collar, we describe when, where and how wolves fish in a freshwater ecosystem. From 2017 to 2021, we recorded more than 10 wolves (Canis lupus) hunting fish during the spring spawning season in northern Minnesota, USA. Wolves ambushed fish in creeks at night when spawning fish were abundant, available and vulnerable in shallow waters. We observed wolves specifically targeting sections of rivers below beaver (Castor canadensis) dams, suggesting that beavers may indirectly facilitate wolf fishing behaviour. Wolves also cached fish on shorelines. We documented these findings across five different social groups at four distinct waterways, suggesting that wolf fishing behaviour may be widespread in similar ecosystems but has probably remained difficult to study given its annual brevity. Spawning fish may serve as a valuable pulsed resource for packs because the spring spawning season coincides with low primary prey (deer Odocoileus virginianus) availability and abundance, and when packs have higher energetic demands owing to newly born pups. We demonstrate the flexibility and adaptability of wolf hunting and foraging behaviour, and provide insight into how wolves can survive in a myriad of ecosystems.
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Affiliation(s)
- Danielle R. Freund
- Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, 2003 Upper Buford Circle, St Paul, MN 55108, USA
| | - Thomas D. Gable
- Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, 2003 Upper Buford Circle, St Paul, MN 55108, USA
| | - Sean M. Johnson-Bice
- Department of Biological Sciences, University of Manitoba, 50 Sifton Road, Winnipeg, Manitoba, Canada R3T 2N2
| | - Austin T. Homkes
- Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, 2003 Upper Buford Circle, St Paul, MN 55108, USA
| | - Steve K. Windels
- Voyageurs National Park, National Park Service, 360 Highway 11 East, International Falls, 56649 MN, USA
| | - Joseph K. Bump
- Department of Fisheries, Wildlife, and Conservation Biology, University of Minnesota, 2003 Upper Buford Circle, St Paul, MN 55108, USA
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Gübelin P, Correa-Cuadros JP, Ávila-Thieme MI, Flores-Benner G, Duclos M, Lima M, Jaksic FM. European Rabbit Invasion in a Semi-Arid Ecosystem of Chile: How Relevant Is Its Role in Food Webs? Life (Basel) 2023; 13:life13040916. [PMID: 37109445 PMCID: PMC10144028 DOI: 10.3390/life13040916] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 03/20/2023] [Accepted: 03/23/2023] [Indexed: 04/03/2023] Open
Abstract
The European rabbit (Oryctolagus cuniculus) is one of the main invasive species in Chile, where it became naturalized ca. 150 years ago. Their high reproductive capacity, lack of specialist predators, and great adaptability favored the settlement of rabbits in diverse mainland and island ecosystems of the country. Recently, rabbits have become central players in semi-arid ecosystems, such as those represented in Las Chinchillas National Reserve in north-central Chile. We undertook to analyze the place and role of rabbits in the food web of that Reserve, based on a bibliographic review and long-term annual data gathered from 1987 until 2022 (36 years). Results showed that the network comprised 77 species, where 69% were primary producers (plants), 18% were mid-level consumers (herbivores), and 13% were top-level consumers (predators). The most connected species in the food web was the rabbit, which positively or negatively affected the species interacting with it. Predators such as Galictis cuja, Geranoaetus polyosoma, Leopardus colocolo, and Puma concolor, and the scavenger Vultur gryphus, could be negatively affected by an eventual decrease (natural or human-caused) in the rabbit population of the Reserve. To the contrary, primary producers such as Oxalis perdicaria, Plantago hispidula, Schizanthus parvulus, Senna cumminggi, and Tropaeolum azureum could be positively affected by an increase in their biomass in response to a decrease in rabbits, favoring native rodents. We consider that analyzing the rabbit-centered food web and its impacts on native interacting species allows a better understanding of the relevance of invasive species in the local community, providing conceptual tools for rabbit management.
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Rodrigues LLV, Moura YBF, Viana JVDS, de Oliveira LRM, Praxedes ÉA, Vieira JDB, Sales SLA, Silva HVR, Luciano MCDS, Pessoa C, Pereira AF. Full confluency, serum starvation, and roscovitine for inducing arrest in the G 0/G 1 phase of the cell cycle in puma skin-derived fibroblast lines. Anim Reprod 2023; 20:e20230017. [PMID: 37101424 PMCID: PMC10124155 DOI: 10.1590/1984-3143-ar2023-0017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 03/22/2023] [Indexed: 04/28/2023] Open
Abstract
The puma population is constantly decreasing, and cloning by somatic cell nuclear transfer can be used to conserve the species. One of the factors determining the success of the development of cloned embryos is the cell cycle stage of the donor cells. We evaluated the effects of full confluency (~100%), serum starvation (0.5% serum), and roscovitine (15 µM) treatments on the cell cycle synchronization in G0/G1 of puma skin-derived fibroblasts by flow cytometric analysis. Also, we assessed the effects of these synchronization methods on morphology, viability, and apoptosis levels using microscopy tools. The results showed that culturing the cells to confluence for 24 h (84.0%), 48 h (84.6%), and 72 h (84.2%) and serum starvation for 96 h (85.4%) yielded a significantly higher percentage of cells arrested in the G0/G1 (P 0.05) phase than cells not subjected to any cell cycle synchronization method (73.9%). Nevertheless, while serum starvation reduced the percentage of viable cells, no difference was observed for the full confluence and roscovitine treatments (P 0.05). Moreover, roscovitine for 12 h (78.6%) and 24 h (82.1%) was unable to synchronize cells in G0/G1 (P 0.05). In summary, full confluency induces puma fibroblast cell cycle synchronization at the G0/G1 stage without affecting cell viability. These outcomes may be valuable for planning donor cells for somatic cell nuclear transfer in pumas.
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Affiliation(s)
| | | | | | | | - Érika Almeida Praxedes
- Laboratório de Biotecnologia Animal, Universidade Federal Rural do Semi-Árido, Mossoró, RN, Brasil
| | - José de Brito Vieira
- Laboratório de Oncologia Experimental, Universidade Federal do Ceará, Fortaleza, CE, Brasil
| | | | | | | | - Claudia Pessoa
- Laboratório de Oncologia Experimental, Universidade Federal do Ceará, Fortaleza, CE, Brasil
| | - Alexsandra Fernandes Pereira
- Laboratório de Biotecnologia Animal, Universidade Federal Rural do Semi-Árido, Mossoró, RN, Brasil
- Corresponding author:
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