scholarly journals Temporal and trophic partitioning promote coexistence between mesocarnivores in a Mediterranean landscape

2020 ◽  
Author(s):  
Iago Ferreiro-Arias ◽  
Jorge Isla ◽  
Pedro Jordano ◽  
Ana Benítez-López

AbstractThe partition of the ecological niche can enhance the coexistence of predators due to differences in how they exploit three main resources: food, space, and time, the latter being an axis that remains often unexplored. We studied niche segregation in a Mediterranean mesocarnivore community in sites where the top predator, the Iberian lynx, is absent, addressing simultaneously two niche axes: the temporal and the trophic axes. Temporal overlap between prey and predator and potential competitors was analysed by comparing daily activity patterns of predators and prey species through data obtained by using 24 camera-traps deployed in three different sites of the Doñana National Park. We further examined the trophic dimension by compiling and analysing diet information in the study area and exploring trophic preferences between potential competitors. We found an overall temporal segregation between trophic generalist species while those species which showed higher values of temporal overlap differ largely in their trophic preferences. Furthermore, we observed an overall high degree of overlap between the activity patterns of predators and their putative prey (the common genet vs small mammals and the red fox vs European rabbit). Our study suggests that coexistence of the different species that compose the mesocarnivore assemblage in Mediterranean landscapes can be facilitated by the marked temporal segregation of the generalist species due to a divergence in the activity patterns, but also by differences in trophic preferences by specialist species when their activity patterns overlap.

Animals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2200
Author(s):  
Fructueux G. A. Houngbégnon ◽  
Daniel Cornelis ◽  
Cédric Vermeulen ◽  
Bonaventure Sonké ◽  
Stephan Ntie ◽  
...  

The duiker community in Central African rainforests includes a diversity of species that can coexist in the same area. The study of their activity patterns is needed to better understand habitat use or association between the species. Using camera traps, we studied the temporal activity patterns, and quantified for the first time the temporal overlap and spatial co-occurrence between species. Our results show that: (i) Two species are strongly diurnal: Cephalophus leucogaster, and Philantomba congica, (ii) two species are mostly diurnal: C.callipygus and C. nigrifrons, (iii) one species is strongly nocturnal: C.castaneus, (iv) and one species is mostly nocturnal: C.silvicultor. Analyses of temporal activities (for five species) identified four species pairs that highly overlapped (Δ^≥ 0.80), and six pairs that weakly overlapped (Δ^ between 0.06 and 0.35). Finally, co-occurrence tests reveal a truly random co-occurrence (plt > 0.05 and pgt > 0.05) for six species pairs, and a positive co-occurrence (pgt < 0.05) for four pairs. Positive co-occurrences are particularly noted for pairs formed by C.callipygus with the other species (except C. nigrifrons). These results are essential for a better understanding of the coexistence of duikers and the ecology of poorly known species (C. leucogaster and C. nigrifrons), and provide clarification on the activity patterns of C. silvicultor which was subject to controversy. Camera traps proved then to be a powerful tool for studying the activity patterns of free-ranging duiker populations.


2020 ◽  
Author(s):  
Michele Zanni ◽  
Francesca Brivio ◽  
Stefano Grignolio ◽  
Marco Apollonio

AbstractInterspecific interactions are key drivers in structuring animal communities. Sympatric animals may show such behavioural patterns as the differential use of space and/or time to avoid competitive encounters. We took advantage of the ecological conditions of our study area, inhabited by different ungulate species, to investigate the spatial and temporal distribution of Capreolus capreolus, Dama dama and Sus scrofa. We estimated intraspecific interaction arising from the concomitant use of resources by using camera trapping. We collected 2741 videos with the three ungulates, which showed peculiar activity patterns. The three species were observed in all the habitat types of the study area over the four seasons, thus highlighting an evident spatial overlap. Moreover, our analysis demonstrated that the three species did not avoid each other through temporal segregation of their activities, rather showing a high overlap of daily activity rhythms, though with differences among the species and the seasons. Despite the high spatial and temporal overlap, the three species seemed to adopt segregation through fine-scale spatial avoidance: at an hourly level, the proportion of sites where the species were observed together was relatively low. This spatio-temporal segregation revealed complex and alternative behavioural strategies, which likely facilitated intra-guild sympatry among the studied species. Both temporal and spatio-temporal overlap reached the highest values in summer, when environmental conditions were more demanding. Given these results, we may presume that different drivers (e.g. temperature, human disturbance), which are likely stronger than interspecific interactions, affected activity rhythms and fine-scale spatial use of the studied species.


Mammalia ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Guido Marcos Ayala ◽  
María Estela Viscarra ◽  
Pedro Sarmento ◽  
Nuno Negrões ◽  
Carlos Fonseca ◽  
...  

AbstractActivity pattern studies can help explain the coexistence of competing species. Between 2001 and 2017 we evaluated the activity pattern overlap of jaguar (Panthera onca), puma (Puma concolor), and their main prey, using camera traps at 17 Amazonian sites in the Greater Madidi-Tambopata Landscape. We used the Kernel density estimation to generate species activity patterns and the overlap between both cats. We then calculated the overlap coefficient (Δ) by carrying out 10,000 bootstraps (95%). Both cats were active 24 h a day. The puma has higher nocturnal activity (57%), whilst jaguar activity is split almost equally between night (53%) and day (47%). We did not find temporal segregation between jaguars and pumas, which showed similar activity patterns with a high overlapping coefficient (Δ4 = 0.84; 0.78–0.91). Also, we did not find significant differences between Male and Female activity patterns for both species (X2 = 0.50, gl = 1, P = 0.47). Moreover, both cats had significant overlap with the activity patterns of their main prey. Temporal segregation was not detected in any of our study sites within the Greater Madidi-Tambopata Landscape, suggesting that in this region, these predators employ other mechanisms to avoid competition.


2016 ◽  
Vol 16 (3) ◽  
Author(s):  
Samuel Renner ◽  
Eduardo Périco ◽  
Göran Sahlén

Abstract A survey of Odonata was carried out in the National Forest FLONA - SFP, Northeastern region of the Rio Grande do Sul state, Brazil. This conservation unit is mainly covered by Mixed Ombrophilous Forest (MOF), a subtype of Atlantic Forest biome, being also areas covered in planted Pinus, planted Araucaria and open fields. Our sampling efforts were conducted in thirty aquatic environments inside this reserve during the period between January 2014 and November 2014. The sampling sites were selected randomly, comprehending lakes, bogs, small streams and river sections, all inserted in the four vegetation types occurring in the reserve. Fortysix species of Odonata were collected and grouped into 23 genera and seven families. The dominant families were Coenagrionidae (32%), Libellulidae (32%), Aeshnidae (12%), and, Calopterygidae and Lestidae (9%). As expected, the findings revealed the presence of a highly diverse Odonate assemblage, mainly represented by generalist species in the most human disturbed sectors (Pinus and Open fields) and some specialist species in the pristine forest. Two species were registered for the first time in the state of Rio Grande do Sul, Brazil: Libellula herculea Karsch, 1889 (Libellulidae) and Heteragrion luizfelipei Machado, 2006 (Heteragrionidae).


2009 ◽  
Vol 59 (2) ◽  
pp. 145-157 ◽  
Author(s):  
Octavio Monroy-Vilchis ◽  
Vicente Urios ◽  
Martha Zarco-González ◽  
Clarita Rodríguez-Soto

AbstractIn this study the habitat use and activity patterns of the two of the largest cats of the Americas in central Mexico were studied. Three ways to detect felid presence were employed from August 2002 to May 2006: interviews, signs, and camera-traps. 478 records were obtained, from which 441 were from cougar and 37 from jaguar. These records included positive response in 118 of 140 interviews and 236 records of signs (mainly tracks and scats), and 124 photographs. Both felids preferred pine-oak forest habitats, with altitudes higher than 1800 m, distances between 3509 and 4377 m from roads, between 2329 and 4650 m from settlements, and distances to very steep slopes between 1048 and 2059 m, for jaguar, and for cougar lower than 1047 m. Jaguar activity was recorded mainly during nighttimes, between 0:00 and 6:00, whereas cougar was active between 4:00 and 6:00 and between 18:00 and 22:00 hours, avoiding the jaguar's principal activity period.


2017 ◽  
Vol 26 (12) ◽  
pp. 1030 ◽  
Author(s):  
Andrew H. Lybbert ◽  
Justin Taylor ◽  
Alysa DeFranco ◽  
Samuel B. St Clair

Wildfire can drastically affect plant sexual reproductive success in plant–pollinator systems. We assessed plant reproductive success of wind, generalist and specialist pollinated plant species along paired unburned, burned-edge and burned-interior locations of large wildfires in the Mojave Desert. Flower production of wind and generalist pollinated plants was greater in burned landscapes than adjacent unburned areas, whereas specialist species responses were more neutral. Fruit production of generalist species was greater in burned landscapes than in unburned areas, whereas fruit production of wind- and specialist-pollinated species showed no difference in burned and unburned landscapes. Plants surviving in wildfire-disturbed landscapes did not show evidence of pollination failure, as measured by fruit set and seed:ovule ratios. Generalist- and specialist-plant species established in the interior of burned landscapes showed no difference in fruit production than plants established on burned edges suggesting that pollination services are conserved with increasing distance from fire boundaries in burned desert landscapes. Stimulation of plant reproduction in burned environments due to competition release may contribute to the maintenance of pollinator services and re-establishment of the native plant community in post-fire desert environments.


Author(s):  
Kelly Pearce ◽  
Tom Serfass

Grand Teton National Park is part of the known range of the North American river otter, however not much is known about this semi-aquatic mammal within the park. The results presented here are part of a larger project to investigate the potential of the river otter (Lontra canadensis) to serve as an aquatic flagship (species that engender public support and action) for the Greater Yellowstone Ecosystem. River otters, known for their charismatic behavior have the potential to serve as an aquatic flagship species to promote conservation of aquatic ecosystems. The primary objective of this portion of the study was to identify river otter latrines on portions of the Snake River, between Flagg Ranch and Jackson Lake, and between Jackson Lake Dam and Pacific Creek, collect river otter scats to determine diet of the river otter, and employ remote cameras to determine activity patterns of the river otters. Between 20 June and 1 July 2015, 26 river otter latrines were identified during shoreline surveys, 186 river otter scats were collected, and cameras were deployed at 6 latrines between 7 July and 24 August 2015. River otter scats have been cleaned and prepared for analysis, but have not all been processed to date. Camera traps recorded 222 images, of which 7% (n = 14) were of carnivores, 70% (n = 155) were of non-carnivore mammals, and 9% (n = 22) were of birds. River otters were detected at 1 of the 6 latrines, a total of 5 independent times during the study.


2008 ◽  
Vol 12 (1) ◽  
pp. 113 ◽  
Author(s):  
Christian Giovanii Estrada Hernández

RESUMEN: La Selva Maya es el bosque tropical de hoja ancha más extenso de Centroamérica, se extiende entre México, Guatemala y Belice. El jaguar y el puma, son los felinos más grandes de América. En esta zona viven simpátricamente por lo que se presupone segregación en alguno de los componentes de su nicho ecológico. En este estudio se analizaron y compararon tres de los componentes principales del nicho: dieta, uso de hábitat y patrones de actividad, con el objetivo de evaluar si existe segregación entre el jaguar y el puma. Para la obtención de los datos se colectaron excrementos de manera oportunista, y se utilizaron trampas de cámaras automáticas en cuatro áreas protegidas. Se analizo la zona de estudio, a través de sistemas de información geográfica para determinar las proporciones de distintos tipos de hábitat presentes, y se colectaron datos de abundancias de las presas. Se analizaron los patrones y en la dieta, en el hábitat utilizado y en el horario de actividad. Se determino que el jaguar tuvo una dieta diferente y mas amplia comparada con la del puma, así también que este consume en promedio, presas más pequeñas. Las presas preferidas por elpuma fueron, tres especies de venados y tepezcuintles. Para el jaguar fueron coches de monte, pizotes y armadillos. Ambas especies presentaron un patrón similar de uso de hábitat, donde el "bosque alto" fue utilizado proporcionalmente a su abundancia, y el puma evitó el "bosque bajo". En cuanto a los patrones de actividad, ambos prefirieron horas nocturnas para desplazarse, aunque el puma presento mayor variabilidad. Se observo que ambas especies no se segregan mutuamente, espacial ni temporalmente. La frecuente utilización del "bosque bajo" y su relación con las aguadas y arroyos, es un factor importante en el mantenimiento de poblaciones de grandes felinos en la Selva MayaPALABRAS CLAVE: Felidae, Panthera onca, Puma concolor, coexistencia, nicho ecológico, Selva Maya, segregación ecológica.ABSTRACT: The Mayan Forest is the largest tropical broad-leaf forest remainder in Central America which extends between Mexico, Guatemala and Belize. Jaguar and puma are the biggest American wild cats. In this area both live sympatric which suggest segregation in at least one of its ecological niche components. In this study I analyzed and compared three of the principal niche components: diet, habitat use and activity patterns, with the main objective of assess if occurs ecological segregation among jaguar and puma. To obtain the data it was collected  jaguar and puma’s scats in an opportunistic way, and was used automatic camera traps in four protected areas. I analyzed the study area by geographic information system (GIS) to determine proportions of different habitat types, and also I used  previous collected prey abundance data. I analyzed patterns in diet, in habitat use and temporal activity. I found that jaguar had a wider prey spectrum than puma; jaguar took (in average) smallest preys, consequently, diets were significantly different. Puma preferred deer, brocket deer and paca as main prey; in contrast, jaguar preferred collared pecari, coati and armadillo. Both predator species presented a similar pattern in habitat usage, in which "highland forest" was used accordingly with its availability and puma avoided "lowland forest". About activity patterns, both were more active in the night time, however, puma was more variable in this aspect. Both species did not show segregation spatially or temporally. KEYWORDS: Felidae, Panthera onca, Puma concolor, coexistence, ecologic niche, Mayan forest, ecologic segregation.


2018 ◽  
Author(s):  
Kimberly J. Gilbert ◽  
Stephan Peischl ◽  
Laurent Excoffier

AbstractThe fitness of spatially expanding species has been shown to decrease over time and space, but specialist species tracking their changing environment and shifting their range accordingly have been little studied. We use individual-based simulations and analytical modeling to compare the impact of range expansions and range shifts on genetic diversity and fitness loss, as well as the ability to recover fitness after either a shift or expansion. We find that the speed of a shift has a strong impact on fitness evolution. Fastest shifts show the strongest fitness loss per generation, but intermediate shift speeds lead to the strongest fitness loss per geographic distance. Range shifting species lose fitness more slowly through time than expanding species, however, their fitness compared at equivalent geographic distances spread can be considerably lower. These counter-intuitive results arise from the combination of time over which selection acts and mutations enter the system. Range shifts also exhibit reduced fitness recovery after a geographic shift and may result in extinction, whereas range expansions can persist from the core of the species range. The complexity of range expansions and range shifts highlights the potential for severe consequences of environmental change on species survival.Author SummaryAs environments change through time across the globe, species must adapt or relocate to survive. Specialized species must track the specific moving environments to which they are adapted, as compared to generalists which can spread widely. During colonization of new habitat, individuals can accumulate deleterious alleles through repeated bottlenecks. We show through simulation and analytic modeling that the process by which these alleles accumulate changes depending upon the speed at which populations spread over a landscape. This is due to the increased efficacy of selection against deleterious variants at slow speeds of range shifts and decreased input of mutations at faster speeds of range shifts. Under some selective circumstances, shifting of a species range leads to extinction of the entire population. This suggests that the rate of environmental change across the globe will play a large role in the survival of specialist species as compared to more generalist species.


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