Forty years of dietary studies on barn owl (Tyto alba) reveal long term trends in diversity metrics of small mammal prey

AbstractThe diet of predators is influenced by local conditions (e.g., characteristics of habitat and microhabitat, seasonality, prey availability) and therefore tends to change across time. In this paper, the diet composition of the barn owl (Tyto alba) in Italy was studied using a meta-analysis of 47 articles (covering 212 independent sites, with multiple surveys for some sites, thus giving a total of 290 datasets) between 1972 and 2012. General Linear Models were used to assess the effects of year and study site on four distinct diversity indices (species richness, dominance, Shannon-Weaver diversity and equitability). The year of data collection was a factor used in all analyses. Year had a greater effect than study site on all diversity indices, but the effect was not significant for the evenness and the species richness. However, dietary dominance increased significantly over the years, the Shannon-Weaver index of diversity decreased significantly over time, and equitability also decreased significantly over time. The relative abundance of various species of rodents did not increase/decrease progressively over the years, although there were inter-annual fluctuations. On the other hand, the relative abundance of insectivores tended to decrease with time, and there was a significantly negative correlation between year and the frequency of consumption of Sorex spp. and a marginally significant negative correlation for Crocidura leucodon.

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Aquatic and semi aquatic Hemiptera community of Sonebeel, the largest wetland of Assam, northeastern India

Journal of Threatened Taxa ◽

10.11609/jott.3440.10.13.12792-12799 ◽

2018 ◽

Vol 10 (13) ◽

pp. 12792-12799

Author(s):

Anupama Saha ◽

Susmita Gupta

Keyword(s):

Species Richness ◽

Pest Control ◽

Relative Abundance ◽

Species Distribution ◽

Diversity Indices ◽

Environmental Data ◽

Northeastern India ◽

Ecological Roles

Aquatic and semiaquatic Hemiptera bugs play significant ecological roles, and they are important indicators and pest control agents. Little information is currently available concerning its populations in southern Assam. This study assessed hemipterans in four sites of Sonebeel, the largest wetland in Assam (3458.12 ha at full storage level), situated in Karimganj District. The major inflow and outflow of the wetland are the rivers Singla and Kachua, respectively (the Kachua drains into the Kushiyara River). Samples were trapped with pond nets and were seasonally recorded. This study recorded a total of 28 species of aquatic and semiaquatic hemipterans belonging to 20 genera under nine families. Population, geographical and environmental data (e.g., rainfall) were used to assess the relative abundance of species, species richness and different diversity indices, and species distribution.

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Nidicolous beetle species richness is driven by Barn Owl’s nests occupancy and landscape structure

Journal of Ornithology ◽

10.1007/s10336-021-01875-z ◽

2021 ◽

Author(s):

Vivien Cosandey ◽

Robin Séchaud ◽

Paul Béziers ◽

Yannick Chittaro ◽

Andreas Sanchez ◽

...

Keyword(s):

Species Richness ◽

Landscape Structure ◽

Barn Owl ◽

Arthropod Community ◽

Tyto Alba ◽

Nest Material ◽

Crop Fields ◽

Nest Boxes ◽

Bird Droppings ◽

Barn Owls

AbstractBird nests are specialized habitats because of their particular composition including nest detritus and bird droppings. In consequence, they attract a specialized arthropod community considered as nidicolous, which includes species only found in bird nests (strictly nidicolous) or sometimes found in bird nests (facultatively nidicolous). Because the factors influencing the entomofauna in bird nests are poorly understood, in autumn 2019, we collected nest material in 86 Barn Owl (Tyto alba) nest boxes. We investigated whether the invertebrate species richness was related to Barn Owl nest box occupancy, the density of available nest boxes and the landscape structure. We found 3,321 nidicolous beetle specimens belonging to 24 species. Species richness of strictly nidicolous beetles was 2.7 times higher in nest boxes occupied by a family of Barn Owls the previous spring compared to unoccupied nest boxes. It was also higher in sites that were more often occupied by Barn Owls in the five previous years and in areas surrounded by a higher proportion of crop fields. For facultatively nidicolous beetles, the density of Barn Owl nest boxes enhanced the species richness. In conclusion, our study suggests that the strictly nidicolous beetles benefit from occupied nest boxes of Barn Owls, whereas facultatively nidicolous beetles look for nest boxes independently of whether Barn Owls occupy them. Our study highlights the importance of bird nests for a suite of invertebrates.

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Meta-analysis of cyathostomin species-specific prevalence and relative abundance in domestic horses from 1975–2020: emphasis on geographical region and specimen collection method

Parasites & Vectors ◽

10.1186/s13071-020-04396-5 ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Jennifer L. Bellaw ◽

Martin K. Nielsen

Keyword(s):

Species Richness ◽

North America ◽

Eastern Europe ◽

Relative Abundance ◽

Linear Models ◽

Meta Analysis ◽

Geographical Region ◽

Mixed Linear Models ◽

Collection Method ◽

Species Specific

Abstract Background Cyathostomins infect virtually all horses, and concomitant infections with 10 or more species per horse is standard. Species-specific knowledge is limited, despite potential species bias in development of disease and anthelmintic resistance. This is the first meta-analysis to examine effects of geographical region and cyathostomin collection method on reported composition of cyathostomin communities. Methods Thirty-seven articles published in English in 1975 or later, in which adults of individual species were systematically enumerated, were included. Seven regions; North America, South America, eastern Europe, western Europe, northern Europe, southern Africa, and Oceania, and three cyathostomin collection methods; (i) standard necropsy recovery from the large intestine, (ii) critical test collection from post-treatment feces and necropsy, and (iii) diagnostic deworming recovery solely from post-treatment feces, were considered. Generalized mixed linear models analyzed the effects of region and collection method on species-specific prevalence and relative abundance. Species richness was analyzed by mixed linear models. Results Definitively, the most prevalent and relatively abundant species were Cylicocyclus nassatus (prevalence = 93%, relative abundance = 20%), Cylicostephanus (Cys.) longibursatus (93%, 20%), and Cyathostomum catinatum (90%, 16%). A bias toward horses with high infection intensities and cyathostomin collection from feces resulted in North American critical tests and eastern European diagnostic deworming overestimating the species-specific prevalence and underestimating the relative abundance of rare/uncommon species compared to respective intra-regional standard necropsies. North American critical tests underestimated species richness due partially to identification key errors. Inter-regional standard necropsy comparisons yielded some species-specific regional differences, including a significantly higher Cys. longibursatus prevalence and relative abundance in North America (92%, 33%) than in eastern Europe (51%, 7%) (P > 0.0001). Localization of critical tests to North America and diagnostic deworming to Eastern Europe precluded expansive ‘region by collection method’ interaction analyses. Conclusion We provide substantial data to inform study design, e.g. effect and study size, for cyathostomin research and highlight necessity for method standardization and raw data accessibility for optimal post-factum comparisons.

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Functional Diversity in Ferns Is Driven by Species Richness Rather Than by Environmental Constraints

Frontiers in Plant Science ◽

10.3389/fpls.2020.615723 ◽

2021 ◽

Vol 11 ◽

Author(s):

Daniela Aros-Mualin ◽

Sarah Noben ◽

Dirk N. Karger ◽

César I. Carvajal-Hernández ◽

Laura Salazar ◽

...

Keyword(s):

Species Richness ◽

Functional Diversity ◽

Environmental Conditions ◽

Linear Models ◽

Environmental Filtering ◽

Diversity Indices ◽

Resource Acquisition ◽

Climate Data ◽

Acquisition Strategies ◽

Functional Diversity Indices

Functional traits determine how species interact with their abiotic and biotic environment. In turn, functional diversity describes how assemblages of species as a whole are adapted to their environment, which also determines how they might react to changing conditions. To fully understand functional diversity, it is fundamental to (a) disentangle the influences of environmental filtering and species richness from each other, (b) assess if the trait space saturates at high levels of species richness, and (c) understand how changes in species numbers affect the relative importance of the trait niche expansion and packing. In the present study, we determined functional diversity of fern assemblages by describing morphological traits related to resource acquisition along four tropical elevational transects with different environmental conditions and species richness. We used several functional diversity indices and their standardized effect size to consider different aspects of functional diversity. We contrasted these aspects of functional diversity with climate data and species richness using linear models and linear mixed models. Our results show that functional morphological trait diversity was primarily driven by species richness and only marginally by environmental conditions. Moreover, increasing species richness contributed progressively to packing of the morphological niche space, while at the same time decreasing morphological expansion until a saturation point was reached. Overall, our findings suggest that the density of co-occurring species is the fundamental driving force of morphological niche structure, and environmental conditions have only an indirect influence on fern resource acquisition strategies.

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Ichthyofauna of the Mata de Itamacaoca, an urban protected area from the upper Munim River basin, Northern Brazilian Cerrado

Biota Neotropica ◽

10.1590/1676-0611-bn-2020-1116 ◽

2020 ◽

Vol 20 (4) ◽

Author(s):

Elioenai da Silva Oliveira ◽

Erick Cristofore Guimarães ◽

Pâmella Silva de Brito ◽

Lucas de Oliveira Vieira ◽

Rafael Ferreira de Oliveira ◽

...

Keyword(s):

Species Richness ◽

River Basin ◽

Fish Species ◽

Fish Community ◽

Linear Models ◽

Anthropogenic Impacts ◽

Sampling Site ◽

Abundant Species ◽

Diversity Indices ◽

Alien Invasive Species

Abstract: The Munim River basin is one of the main river drainages of the Hydrological unit Maranhão, but there are few published studies which focus on ichthyological surveys and taxonomic work within this basin. The present study aims to provide a fish species inventory of the Mata da Itamacaoca, one of the few urban protected areas from the upper Munim River basin, comparing the ichthyofauna with other lists by conducted at the upper Munim River basin. A total of 42 collection expeditions were conducted, the sampling was conducted at five collecting sites distributed within the boundaries of Mata de Itamacaoca, upper Munim River basin. Diversity indices were calculated and generalised linear models (GLMs) were employed to assess differences in species richness, diversity and evenness depending on season and location in relation to the reservoir dam wall. In order to visualize fish community differences, non-metric multidimensional scaling (nMDS) and a one-way PERMANOVA was used to understand whether factors of site, season and location to the dam wall had an effect on fish community compositions. A total of six orders, 13 families, and 23 fish species were found, and the order with the highest species richness, considering all reaches, was Characiformes followed by Cichliformes. The most abundant species was Nannostomus beckfordi, while Pimelodella parnahybae and Hoplerythrinus unitaeniatus were the rarer species sampled. There were no alien invasive species collected within the study area. Species richness was significantly higher below the dam wall, but there were no other significant differences in diversity indices with regards to season or location. Fish community composition was significantly different above and below the dam wall and was significantly affected by sampling site. Season did not have an effect on fish community. This study corroborates other studies conducted in the Unidade Hidrológica Maranhão sensu Hubbert and Renno (2006), that the ichthyofaunal composition and taxonomy of species within this region face major data deficits, anthropogenic impacts, this study may be a baseline for comparing similar environments throughout the region.

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The prey composition of the Barn Owl (Tyto alba) with respect to landscape structure of its hunting area (Zala County, Hungary)

Ornis Hungarica ◽

10.1515/orhu-2017-0015 ◽

2017 ◽

Vol 25 (2) ◽

pp. 51-64

Author(s):

Dávid Szép ◽

Ákos Klein ◽

Jenő J. Purger

Keyword(s):

Relative Abundance ◽

Small Mammal ◽

Landscape Structure ◽

Barn Owl ◽

Tyto Alba ◽

Mammal Species ◽

Prey Composition ◽

Barn Owls ◽

Landscape Patches ◽

Small Mammal Species

Abstract The prey composition of the Barn Owl (Tyto alba) can be monitored indirectly by pellet analysis and we used this method to investigate less known small mammal species of Zala County. The number and abundance of small mammal species depend on the structure of the landscape of Barn Owls’ hunting area, therefore we analysed landscape features in the surrounding circles with 2 km radius around the sampling sites. In 2016 we collected 1106 pellets from 13 sampling localities. From the pellets we identified 21 species of 3022 individuals of small mammals (more than 98% of prey). Among the 21 species there was the rare Parti-colured Bat (Vespertilio murinus) and a new species for the county the Steppe Mouse (Mus spicilegus). Positive correlation was found between the diversity of the small mammal fauna of each sampling site and the landscape complexity (number of the landscape patches) of the Barn Owl hunting area. Relative abundance of the Wood Mouse (Apodemus sylvaticus) showed positive correlation with the number of landscape patches, while the abundance of the Lesser White-toothed Shrew (Crocidura suaveolens), the Miller’s Water Shrew (Neomys anomalus), the Striped Field Mouse (Apodemus agrarius) and the Harvest Mouse (Micromys minutus) was higher in hunting areas with more homogenous landscapes. Significant correlations were found between the relative abundance of some small mammal species and the landscape structure of the potential hunting area of owls that confirmed the consistency in habitat preference of some species. Our results proved that the prey-composition of Barn Owls reflects the land use through the distribution and abundance of small mammal species, therefore this method is suitable for ecological analyses of landscape.

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Diversity of nematodes in the yellow-necked field mouseApodemus flavicollisfrom the Peripannonic region of Serbia

Journal of Helminthology ◽

10.1017/s0022149x14000698 ◽

2014 ◽

Vol 90 (1) ◽

pp. 14-20 ◽

Cited By ~ 3

Author(s):

B. Čabrilo ◽

V.M. Jovanović ◽

O. Bjelić-Čabrilo ◽

I. Budinski ◽

J. Blagojević ◽

...

Keyword(s):

Species Richness ◽

Generalized Linear Models ◽

Linear Models ◽

Alpha Diversity ◽

Nematode Species ◽

Diversity Indices ◽

Taxonomic Distinctness ◽

Field Mouse ◽

Apodemus Flavicollis ◽

Longitudinal Gradient

AbstractUp to six nematode species were identified from 86 specimens of the yellow-necked field mouseApodemus flavicollisfrom three mountainous localities known as Avala, Cer and Liškovac in Serbia. The highest prevalence of infection of 97% was recorded from Mt. Avala. Only one nematode species,Syphacia frederici, occurred in all three localities. There was complete overlap in nematode species from Mts. Avala and Liškovac, whereas the taxonomic distinctness of Mt. Cer was seen in the presence of the insect-transmitted speciesRictularia proni. Locality was a statistically significant factor in all the best-fitted generalized linear models of variation in abundances. The highest level of both species richness and parasite alpha diversity (Shannon'sH= 1.47) was found in the easternmost Mt. Liškovac, whereas the diversity indices were lowest for the westernmost Mt. Cer (Shannon'sH= 0.48). In view of this geographical difference, the beta diversity indices were calculated along a west to east longitudinal gradient.

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