Floral resources and habitat affect the composition of hummingbirds at the local scale in tropical mountaintops

Hummingbird communities tend to respond to variation in resources, having a positive relationship between abundance and diversity of food resources and the abundance and/or diversity of hummingbirds. Here we examined the influence of floral resource availability, as well as seasonality and type of habitat on the composition of hummingbird species. The study was carried out in two habitats of eastern Brazilian mountaintops. A gradient representative of the structure of hummingbird community, based on species composition, was obtained by the ordination of samples using the method of non-metric multidimensional scaling. The composition of hummingbird species was influenced by the type of habitat and floral resource availability, but not by seasonality. Hummingbird communities differ between habitats mainly due to the relative abundance of hummingbird species. The variation in composition of hummingbird species with the variation in floral resource availability may be related to differences in feeding habits of hummingbirds. Hummingbird species with the longest bills visited higher proportions of ornithophilous species, while hummingbirds with shorter bills visited higher proportions of non-ornithophilous species. The results demonstrate that at local-scale the composition of hummingbird species is affected by the type of habitat and floral resources availability, but not by seasonality.

Download Full-text

Exploitative competition and displacement mediated by eusocial bees: experimental evidence in a wild pollinator community

Behavioral Ecology and Sociobiology ◽

10.1007/s00265-020-02924-y ◽

2020 ◽

Vol 74 (12) ◽

Author(s):

Veronica R. Wignall ◽

Matthew Brolly ◽

Cassandra Uthoff ◽

Kala E. Norton ◽

Hannah M. Chipperfield ◽

...

Keyword(s):

Resource Availability ◽

Resource Competition ◽

Landscape Management ◽

Resource Depletion ◽

Floral Resources ◽

Exploitative Competition ◽

Ecological Release ◽

Pollinator Community ◽

Eusocial Bees ◽

Floral Resource

Abstract Eusocial bees are likely to be ecologically important competitors for floral resources, although competitive effects can be difficult to quantify in wild pollinator communities. To investigate this, we excluded honeybees (HBE treatment), bumblebees (BBE) or both (HB&BBE) from wild-growing patches of bramble, Rubus fruticosus L. agg., flowers in two eight-day field trials at separate locations, with complementary mapping of per-site local floral resource availability. Exclusions increased per-flower volume of nectar and visitation rates of non-excluded bees, compared to control patches with no bee exclusions (CON). There was a large increase in average nectar standing crop volume both at Site 1 (+ 172%) and Site 2 (+ 137%) in HB&BBE patch flowers, and no significant change in HBE or BBE, compared to CON patches. Foraging bee responses to exclusion treatments were more pronounced at Site 2, which may be due to lower local floral resource availability, since this is likely to increase the degree of exploitative competition present. Notably, at Site 2, there was a 447% increase in larger-bodied solitary (non-Apis/Bombus) bees visiting HB&BBE patches, suggesting ecological release from competition. Hoverflies showed no response to bee removals. Numbers of other non-bee insect groups were very small and also showed no clear response to exclusions. Our findings reveal patterns of competitive exclusion between pollinator groups, mediated by resource depletion by eusocial bees. Possible long-term implications of displacement from preferred flowers, particularly where alternative forage is reduced, are discussed. Significance statement Understanding patterns of exploitative competition and displacement is necessary for pollinator conservation, particularly for vulnerable or threatened species. In this research, experimental methods reveal underlying patterns of resource competition exerted by eusocial bees in a wild pollinator community. We show that honeybees and bumblebees competitively displace each other and particularly solitary (non-Apis/Bombus) bees from bramble, an important native nectar and pollen source. Effects were stronger where local floral resource availability was identified to be limited. Notably, following experimental exclusion of both honey- and bumblebees from flowers, visitation by solitary bees increased by up to 447%, strongly suggesting ecological release from competition. These results highlight the need for informed landscape management for pollinator wellbeing, including appropriate honeybee stocking densities and improved floral resource availability.

Download Full-text

Diversity of Macro Invertebrates and Their Habitat Characteristics in Lan-Kuu Freshwater Wetland, Myanmar

American Journal of Pure and Applied Biosciences ◽

10.34104/ajpab.021.01350144 ◽

2021 ◽

pp. 135-144

Keyword(s):

Species Composition ◽

Relative Abundance ◽

Shannon Index ◽

Habitat Characteristics ◽

Local People ◽

Freshwater Wetland ◽

Abundance And Diversity ◽

Number Of Individuals

Lan-Kuu freshwater wetland of Auk SaThar in Mingin Township, Sagaing Region was investigated for its species composition, relative abundance, and diversity of aquatic macro-invertebrates from June 2020 to January 2021. This wetland has water throughout the year and is used by many local people for fishing and trapping birds. Thirty macro invertebrates’ species belonging to 28 genera, 19 families, 11 orders, 5 classes, and 3 Phyla were identified and recorded. These species belonged to the orders Hemiptera (23%), Coeleoptera and Odonata (14% each), Orthoptera, Architaenioglossa and Sorbeoconcha (10% each), Lepidoptera (7%), and Hymenoptera, Araneae, Decapoda, and Opithopora (3%). Among the collected specimens Dytiscus verticalis accounted for the highest number of individuals while the least number of individuals were Arocatus rusticus. Average relative abundance indicated 9 species as ‘uncommon’, 14 species as ‘common’ and 7 species as very common in the studied wetland. According to the Shannon index, the diversity of macro-invertebrates recorded in Lan-Kuu freshwater wetland, Myanmar, was high, (2.746-3.016), and so was the evenness (0.888-0.956).

Download Full-text

Abundance and Diversity of Birds in the Ogbese Forest Reserve, Ekiti State, Nigeria

Asian Journal of Research in Zoology ◽

10.9734/ajriz/2019/v2i230063 ◽

2019 ◽

pp. 1-9

Author(s):

O. O. Ogunyemi

Keyword(s):

Species Composition ◽

Relative Abundance ◽

Bird Species ◽

Natural Forest ◽

Vegetation Types ◽

Plantation Forest ◽

Forest Reserve ◽

Dry Seasons ◽

Abundance And Diversity ◽

Wet And Dry Seasons

A study was carried out to evaluate the species composition and relative abundance of bird species of the natural and plantation forest of Ogbese Forest Rserve, Ekiti State. The study was conducted from April, 2010 to February, 2011 covering both wet and dry seasons. Sample sites were stratified based on the vegetation types and transect count techniques was employed for the evaluation. A total of 52 bird species consisting of 47 resident and 5 immigrant species was recorded. The species composition of birds during the wet and dry seasons was not significantly different. The natural forest vegetation had the highest species diversity and evenness. The relative abundance score of species during the Wet and dry seasons was variable in both habitats. The result of this study has shown that the natural and plantation vegetation types of Ogbese Forest Reserve, Ekiti State. The heterogeneity of flora species in the natural forest compared to the plantation forest might be responsible for the variation. The management of birds in the reserve should take cognisance of the vegetation types for effective conservation of bird species which are resident in the reserve.

Download Full-text

Landscape Integrity Eclipses Local Effects of Floral Resource Availability on Bumble Bee (Bombus Spp.) Abundance in a Water-Limited Island Ecosystem

10.21203/rs.3.rs-1128511/v1 ◽

2021 ◽

Author(s):

Andrew Simon ◽

Brian M. Starzomski

Keyword(s):

Resource Availability ◽

Natural Habitat ◽

Landscape Scale ◽

Floral Resources ◽

Bumble Bee ◽

Late Season ◽

Habitat Integrity ◽

Matrix Habitat ◽

Bee Community ◽

Floral Resource

Abstract ContextHabitat loss threatens to exacerbate climate change impacts on pollinator communities, particularly in Mediterranean-type ecosystems where late season floral resource availability is limited by seasonal drought. While gardens have been found to supplement floral resources in water-limited urban landscapes, less is known about the role of natural habitat diversity in sustaining late season floral resources in more intact landscapes. ObjectivesWe investigated the importance of habitat integrity and diversity for bumble bees in a water-limited ecosystem, observing bumble bee community response to seasonal drought across gradients of disturbance and soil moisture.MethodsWe applied hierarchical models to estimate the effects of local site conditions versus landscape scale estimates of matrix habitat on bumble bee abundance. Floral resources, soil moisture, and other environmental variables were sampled along randomly distributed belt transects. Geospatial estimates of matrix habitat were derived from terrestrial ecosystem data. Bumble bees were sampled with blue vane traps.ResultsIn the late season we found that modified wet areas supported more floral resources and bumble bee workers as compared to dry semi-natural environments. Wetlands also supported more late season floral resources and bumble bee workers, though the latter effect was not significant. Despite higher levels of late season floral resources in modified wet environments, modified matrix habitat was negatively associated, and natural matrix positively associated, with workers in June and late-flying queens in July and August. We also detected differences in bumble bee community composition in disturbed versus undisturbed environments.ConclusionsThough wet modified habitats sustained the highest levels of late season floral resource availability and worker abundances in our study, bumble bee diversity and abundance were limited primarily by the availability of natural matrix habitat at the landscape scale. The conservation of natural habitat integrity and diversity can help support critical nesting and foraging habitat, and should be prioritized in efforts to foster the resilience of pollinator communities.

Download Full-text

Species Composition, Relative Abundance and Diversity of Ants Associated with Lac Insect in Assam

International Journal of Current Microbiology and Applied Sciences ◽

10.20546/ijcmas.2019.804.216 ◽

2019 ◽

Vol 8 (04) ◽

pp. 1852-1859

Author(s):

Rituraj Saikia ◽

Purnima Das ◽

Lakshmi Kanta Hazarika ◽

Athar Nishat Islam ◽

Surajit Kalita ◽

...

Keyword(s):

Species Composition ◽

Relative Abundance ◽

Lac Insect ◽

Abundance And Diversity

Download Full-text

FLORAL BIOLOGY AND BEEKEEPING POTENTIAL OF Croton heliotropiifolius KUNTH (EUPHORBIACEAE) AT SEMI ARID REGION, BRAZIL1

Revista Caatinga ◽

10.1590/1983-21252021v34n417rc ◽

2021 ◽

Vol 34 (4) ◽

pp. 895-903

Author(s):

VANDERLEI DA SILVA OLIVEIRA ◽

JOSÉ MONTEIRO DO NASCIMENTO JÚNIOR ◽

RICARDO LANDIM BORMANN DE BORGES ◽

LUCIENE CRISTINA LIMA E LIMA

Keyword(s):

Apis Mellifera ◽

Resource Availability ◽

Arid Region ◽

Pollen Grains ◽

Floral Biology ◽

Floral Resources ◽

Flower Production ◽

Semi Arid Region ◽

Floral Resource ◽

Semi Arid

ABSTRACT The aim of the present study was to determine the beekeeping potential of Croton heliotropiifolius Kunth (Euphorbiaceae) based on flowering strategy, floral characteristics, available floral resources, and the individuals frequencies and foraging activities of Apis mellifera L. on its flowers in Fazenda Ingazeira, Brazil. Each C. heliotropiifolius plant possessed inconspicuous diclinous flowers clustered into 560 ± 60 dense terminal inflorescences containing 59 ± 12 pistillate and 160 ± 26 staminate flowers. Although both types of flowers produced nectar (pistillate: 2.8 ± 0.8 μL ; staminate: 0.3 ± 0.06 μL ), A. mellifera workers mostly visited staminate flowers (98%) during the peak visitation period (08:00-11:00 h). Moreover, during the foraging period, each plant produced approximately 5.376 × 10 8 pollen grains, ensuring approximately 33 visitation cycles from a colony of A mellifera workers that picked up an average of 405 pollen grains per visit per flower. Further, C. heliotropiifolius showed an annual cornucopia flowering strategy with high flower production for five months, which is an important characteristic that ensures floral resource availability in the environment. These findings suggest that C. heliotropiifolius has a great potential for apiculture in this region.

Download Full-text

The Species Composition and Relative Abundance of Insect Pests of Stored Faba Bean in Farta District of South Gondar Zone of North Western Ethiopia

Journal of Basic & Applied Sciences ◽

10.29169/1927-5129.2020.16.04 ◽

2020 ◽

Vol 16 (1) ◽

pp. 31-38

Author(s):

Wondale Endshaw ◽

Keyword(s):

Species Composition ◽

Relative Abundance ◽

Faba Bean ◽

Insect Pests ◽

North Western ◽

South Gondar ◽

Western Ethiopia

Download Full-text

Dynamics of Diversity and Abundance of Sulfonamide Resistant Bacteria in a Silt Loam Soil Fertilized by Compost

Antibiotics ◽

10.3390/antibiotics10060699 ◽

2021 ◽

Vol 10 (6) ◽

pp. 699

Author(s):

Hui Han ◽

Mohan Bai ◽

Yanting Chen ◽

Yali Gong ◽

Ming Wu ◽

...

Keyword(s):

High Throughput ◽

Relative Abundance ◽

High Throughput Sequencing ◽

Resistant Bacteria ◽

Arable Soils ◽

Soil Bacterial Communities ◽

Sulfonamide Resistance ◽

Loam Soil ◽

Abundance And Diversity ◽

Sulfonamide Resistance Genes

Although composting is effective in deactivating antibiotic substances in manure, the influence of compost fertilization on the occurrence and dissemination of antibiotic resistance in arable soils remains to be controversial. Herein, the abundance and diversity of two sulfonamide resistance genes (sul1 and sul2) in soil fertilized by compost spiked with two concentrations of sulfadiazine (1 and 10 mg kg−1) were studied intensively by qPCR and high throughput sequencing based on a two-month microcosm experiment. The concentration of sulfadiazine decreased rapidly after spiking from 25% at Day 1 to less than 2.7% at Day 60. Relative abundance of both sul1 and sul2 were significantly higher in soil amended with compost than the non-amended control at Day 1 and slightly decreased with incubation time except for sul2 in the S10 treatment. Soil bacterial communities were transiently shifted by compost fertilization regardless of the presence of sulfadiazine. Relative abundance of genera in three hubs positively interlinked with sul1 and sul2 were significantly higher in compost treated soil than the control at Day 1, 7 and 21, but not at Day 60. High throughput sequencing analyses revealed that most detected (>67% in relative abundance) sul1 and sul2 genotypes sharing >99% similarity with those found in gammaproteobacterial pathogens frequently were commonly present in compost and soil. These results indicated that compost fertilization might increase the abundance rather than diversity of sulfadiazine-resistant populations in soil, which may be facilitated by the presence of sulfadiazine.

Download Full-text