scholarly journals Comparison of prey availability for Setophaga petechia gundlachi (Aves: Parulidae) between two mangroves with different vegetation structure

Caldasia ◽  
2020 ◽  
Vol 43 (1) ◽  
pp. 28-38
Author(s):  
Alejandro Rodríguez Ochoa ◽  
Martín Acosta Cruz
Keyword(s):  
Breeding Season ◽  
Vegetation Structure ◽  
Urban Landscape ◽  
Prey Availability ◽  
Mangrove Species ◽  
Santa Ana ◽  
A Value ◽  
Structure Changes ◽  
Lower Height ◽  
Setophaga Petechia

The subspecies Setophaga petechia gundlachi is characterized by its specificity to mangrove habitat during the breeding season. The objective of this work was to compare the prey availability for S. petechia gundlachi during the breeding season in two mangrove sites with different vegetation structure in Havana, Cuba. To describe different levels of vegetation structure between both mangrove sites, we took several variables at 50 plots. Besides, we recorded the foraging behavior of S. petechia gundlachi to establish the design of prey availability sampling. We measured prey availability by using the branch clipping method, about 90 samples were collected at each mangrove site. Bajo de Santa Ana mangrove, with a lower height and diameter at breast height, showed evidence of deforestation. Laguncularia racemosa was the most used mangrove species for foraging and offered the highest biomass of available prey in the Laguna de Cobre-Itabo mangrove site. The greatest biomass of available prey was found at the Laguna de Cobre-Itabo, with a value of 5.1 (CI: 4.0 - 6.2) mg / 100 g of branch clipping. The Bajo de Santa Ana site had a lower value than expected 1.6 (CI: 0.8 - 1.7) mg / 100 g of branch clipping. The results provide evidence of the possible influence of mangrove vegetation structure changes on food availability for S. petechia gundlachi in this urban landscape.

scholarly journals Vegetation structure and decreased moth abundance limit the recolonisation of restored habitat by the European Nightjar

2018 ◽  
Vol 3 ◽  
pp. 25-39 ◽  
Author(s):  
Nathalie Winiger ◽  
Pius Korner ◽  
Raphaël Arlettaz ◽  
Alain Jacot
Keyword(s):  
Vegetation Structure ◽  
Habitat Restoration ◽  
Stand Structure ◽  
Prey Availability ◽  
Population Declines ◽  
Major Transitions ◽  
Slowing Down ◽  
Open Forest ◽  
Mineral Soils ◽  
Management Recommendations

Woodland ecosystems of Europe have undergone major transitions in the last centuries. Changes in land use and the loss of natural forest dynamics have often led to structurally poor, uniform and dense stands. Not surprisingly, open forest species relying on a heterogeneous stand structure have suffered dramatic population declines. The European Nightjar Caprimulguseuropaeus, a nocturnal insectivorous bird, has undergone such a decline in its main Swiss stronghold in Valais. Despite the species’ potential to colonize new sites and habitat restoration measures implemented since 2001, recolonisation of restored sites has not taken place, suggesting problems with the current habitat restoration strategy. In order to refine management recommendations, we compared habitat structure and moth abundance, a key Nightjar food source, at sites that are still occupied and at sites that had been abandoned but have recently been restored. Vegetation structure was more heterogeneous and moth abundance greater at occupied than at abandoned sites. More specifically, occupied sites harboured a greater coverage of bare ground, while abandoned sites exhibited a higher amount of regeneration and intermediate shrub layer. The occurrence of natural perches was also higher in occupied sites. Abandoned sites are thus characterised by lower prey abundance and denser vegetation cover, the combination of which is likely to lead to lower prey availability for hunting Nightjars. Restoration action would benefit from maintaining snags and dead branches and by targeting unproductive habitats characterised by mineral soils, thereby slowing down regeneration and shrub regrowth. For future successful management of Nightjar habitats, it seems thereby essential trying to find the balance between actions that allow opening the lower and mid-strata of the forest while sustaining high moth populations.

Defining Commitments through Spiritual Dialogue

2020 ◽  
pp. 145-178
Author(s):  
Jonathan E. Calvillo
Keyword(s):  
Urban Landscape ◽  
Spiritual Guidance ◽  
Santa Ana ◽  
Divine Guidance

This chapter argues that religious commitments are often articulated by Santaneros as a sense of ongoing communication with divine and spiritual entities. This particular pattern signals commonality between Catholics and evangelicals in that members of both groups emphasize seeking spiritual guidance through their choices of religious commitments. Though Catholics and evangelicals differ in some of their respective practices related to communicating with spiritual entities, the expectations of divine guidance are similar. I argue that notions of spiritual dialogue are especially helpful to Santaneros as they evaluate the diverse religious options at their disposal. Santaneros concretize and affirm their religious commitments through practices of divine conversation. In navigating the ethnic space of Santa Ana, divine dialogue imbues the urban landscape with a sense of supernaturalism.

scholarly journals Ekosistem mangrove sebagai habitat kepiting bakau (Scylla Serrata) di Kampung Nipah Desa Sei Nagalawan Kecamatan Perbaungan Serdang Bedagai Provinsi Sumatera Utara

DEPIK ◽  
2018 ◽  
Vol 7 (1) ◽  
pp. 84-90
Author(s):  
Sari Marina Saragi ◽  
Desrita Desrita
Keyword(s):  
Regression Analysis ◽  
Correlation Coefficient ◽  
Vegetation Structure ◽  
High Density ◽  
Scylla Serrata ◽  
A Value ◽  
Mangrove Crab ◽  
Mangrove Vegetation ◽  
Mangrove Crabs

Highly Utilization of Mangrove field as cultivation field of fish and recreation and tour site by people have big posses to the abundance of Mangrove crab (Scylla serrata) because of mangrove play role as habitats of mangrove crabs. The research was conducted for two months from December 2016 to January 2017. This study aims to see the structure of mangrove vegetation, the abundance of Mangrove Crab and the influence of mangrove vegetation structure on the abundance of Mangrove Crab in Kampung Nipah. The results of this research are Vegetation structure of Mangrove in the station I and II show high density, whereas density in station III wide apart. The abundance of mangrove crab in the station I and II showed the higher result from station III. The Influence of Vegetation Structure of Mangrove and Abundance of Mangrove Crab can be related by using regression analysis Y = 0.0241x + 113.6. The correlation coefficient (r) that value obtained as 0.79 have a meaning the connection between mangrove density and abundance of mangrove crab are rated in the strong category that has a value 79%. The density of Mangrove to 1000 units will rise up the abundance of mangrove crab to 43.5 an individual. Tingginya pemanfaatan mangrove sebagai lahan budidaya ikan dan sebagai wisata rekreasi oleh masyarakat sangat mempengaruhi kelimpahan Kepiting Bakau (Scylla serrata) karena hutan mangrove merupakan habitat bagi Kepiting Bakau. Penelitian ini dilaksanakan selama dua bulan yaitu bulan Desember 2016 sampai Januari 2017. Penelitian ini bertujuan untuk melihat struktur vegetasi mangrove, kelimpahan Kepiting Bakau dan pengaruh struktur vegetasi mangrove terhadap kelimpahan Kepiting Bakau di Kampung Nipah. Hasil dari penelitian struktur vegetasi mangrove di stasiun I dan II memiliki kerapatan sangat padat, sedangkaan kerapatan di stasiun III jarang. Kelimpahan Kepiting Bakau di Stasiun I dan II lebih tinggi dari kelimpahan di stasiun III. Pengaruh kerapatan mangrove dan kelimpahan Kepiting Bakau diperoleh persamaan regresi yaitu Y = 43,521 +  0,2061x.  Koefisien korelasi (r) yang diperoleh 0,79 yang artinya hubungan kerapatan mangrove dan kelimpahan Kepiting Bakau tergolong kuat yaitu sebesar 79%. Kerapatan mangrove sebanyak 1000 satuan akan meningkatkan kelimpahan Kepiting Bakau sebesar 43,5 individu.

Effect of age and breeding season on sperm acrosin activity in the arctic fox (Alopex lagopus L.)

2014 ◽  
Vol 17 (1) ◽  
pp. 177-179 ◽  
Author(s):  
K. Stasiak ◽  
B. Janicki
Keyword(s):  
Breeding Season ◽  
The Arctic ◽  
Arctic Fox ◽  
Alopex Lagopus ◽  
A Value ◽  
Arctic Foxes ◽  
The Mean ◽  
One Year ◽  
Acrosin Activity ◽  
Effect Of Age

Abstract The objective of this study was to determine the effect of age and reproductive season on selected properties of semen from the arctic fox, Alopex lagopus L. The experiment used 40 ejaculates collected manually from 6 animals (3 foxes aged one year and 3 foxes older than three years). Statistically less semen (0.39 cm3) was collected from the young compared to the older animals, and the ejaculates obtained were characterized by higher concentration of spermatozoa (195.04 x 106/cm3). In turn, sperm acrosomal extracts from the older animals contained statistically more acrosin (6,4 mU/106 spermatozoa). In the sperm acrosomal extracts prepared during the first semen sampling, the mean acrosin activity did not exceed 2.3 mU/million spermatozoa. At subsequent semen sampling dates, the activity of the analysed enzyme increased to reach 7.72mU/million spermatozoa. In the extracts obtained from the semen collected at the end of the breeding season of arctic foxes, the acrosin activity again reached a value obtained at the beginning of the season.

Winter habitat selection by a montane forest bird assemblage: the effects of solar radiation

2001 ◽  
Vol 79 (2) ◽  
pp. 279-284 ◽  
Author(s):  
Daniel L Huertas ◽  
José A Díaz
Keyword(s):  
Solar Radiation ◽  
Vegetation Structure ◽  
Prey Availability ◽  
Bird Species ◽  
Principal Component ◽  
Interspecific Variation ◽  
Montane Forest ◽  
Bird Abundance ◽  
Winter Habitat ◽  
Movement Rates

A relationship between sunlight and bird abundance in cold climates may seem intuitive and perhaps obvious. However, there is, surprisingly, little or no evidence to support it. We investigated the effects of solar radiation on the winter abundance of insectivorous birds inhabiting a Mediterranean montane forest with a high frequency of cold, cloudless days. We censused birds by ear in 20 different forest tracts in which we simultaneously quantified a number of variables related to the availability of solar radiation, vegetation structure, arthropod abundance, and altitude. All variables related to solar radiation were reduced to a single principal component that attained high scores for south-facing transects, where many tree trunks received direct sunlight for a long period daily. The abundance of all bird species was positively related to the scores of transects on this component after the effects of vegetation structure, altitude, and prey availability were controlled for. Solar radiation was the main predictor of overall abundance and species richness of bird assemblages. Body mass and diet (insectivorous vs. mixed) explained 94.6% of interspecific variation in the strength of the relationship between solar radiation and bird abundance. We hypothesize that selecting forest sectors with a higher availability of sunlit patches allows birds to improve their winter survival by reducing the metabolic costs of thermoregulation, decreasing movement rates, and (or) increasing the time spent motionless in safe locations.

Consequences of forest fragmentation on territory quality of male Ovenbirds breeding in western boreal forests

2002 ◽  
Vol 80 (11) ◽  
pp. 1841-1848 ◽  
Author(s):  
Daniel F Mazerolle ◽  
Keith A Hobson
Keyword(s):  
Forest Fragmentation ◽  
Vegetation Structure ◽  
Boreal Forests ◽  
Prey Availability ◽  
Forest Fragments ◽  
Territory Quality ◽  
Seiurus Aurocapillus ◽  
Prey Biomass ◽  
Prey Composition ◽  
Territory Selection

We evaluated the effects of forest fragmentation caused by agriculture on arthropod prey biomass and vegetation structure found in territories of male Ovenbirds (Seiurus aurocapillus) breeding in the southern boreal mixed woods of Saskatchewan, Canada. The objective of this study was to determine if previously documented differences in pairing success of male Ovenbirds in contiguous forests and forest fragments in our study area were associated with differences in arthropod prey biomass and vegetation structure between contiguous and fragmented forests. A secondary objective was to examine the correspondence between vegetation and arthropods to evaluate whether vegetation cues could be useful for birds attempting to predict future arthropod biomass during territory selection. Our results indicate that both vegetation structure and arthropod prey composition in Ovenbird territories differed between fragmented and contiguous forests, whereas total arthropod biomass did not. Furthermore, the correspondence of vegetation with arthropod prey composition and total prey biomass was weak, a result that questions the use of vegetation structure by male Ovenbirds for predicting future prey availability during territory selection. Overall, the current extent of forest fragmentation in our study area is not likely reducing pairing success of territorial male Ovenbirds by lowering the biomass of arthropod prey. However, landscape differences in vegetation structure could influence pairing success of male Ovenbirds in forest fragments by reducing suitable microhabitats for nesting or by increasing habitat suitability for nest predators and Brown-headed Cowbird (Molothrus ater) parasites.

scholarly journals Vegetation Structure and Damage Level Mangrove Forest in Manomadehe Island, Subdistrict South Jailolo, North Maluku Province

2021 ◽  
Vol 21 (1) ◽  
pp. 222
Author(s):  
Salim Abubakar ◽  
Riyadi Subur ◽  
Masykhur Abdul Kadir ◽  
Rina Rina ◽  
Adi Noman Susanto ◽  
...  
Keyword(s):  
Relative Density ◽  
Vegetation Structure ◽  
Mangrove Forest ◽  
Mangrove Forests ◽  
Mangrove Species ◽  
Rhizophora Stylosa ◽  
Xylocarpus Granatum ◽  
Sonneratia Alba ◽  
Mangrove Vegetation ◽  
Ceriops Tagal

Mangrove forest is a natural resource typical of tropical coasts, which has multiple benefits with a very broad impact when viewed from social, economic and ecological aspects. Management of natural resources must be very prudent because it takes a long time to be able to recover when damage / extinction has occurred. The purpose of this study was to determine the composition of mangrove species, the structure of mangrove forest vegetation (species density, relative density of species, frequency of species, relative frequency of species, species cover, relative cover of species and important values) and to determine the level of damage. Extraction of mangrove vegetation using the "spot check" method. The transects are drawn perpendicular to the coastline along the mangrove vegetation. The composition of mangrove species were 7 species, namely Rhizophora apiculata, R. stylosa, Bruguirea gymnorrhiza, Ceriops tagal, Sonneratia alba, Xylocarpus granatum and Aegiceras floridum. In the vegetation structure, the highest density and relative density were found in Rhizophora stylosa and the lowest was Xylocarpus granatum. The highest species and relative frequencies were Rhizophora stylosa, R. apiculata and the lowest were Bruguiera gymnorrhiza. The highest type and closure were Sonneratia alba and the lowest was Ceriops tagal. Meanwhile, the highest importance was in Sonneratia alba and the lowest was Xylocarpus granatum. Overall, the density value of mangrove species on Manomadehe Island is 2796 trees / ha so that the condition of the mangrove forests on Manomadehe Island is still in the good category (very dense).

scholarly journals Interactions among Land, Water, and Vegetation in Shoreline Arthropod Communities

2004 ◽  
Vol 3 (2) ◽  
Author(s):  
Randall Willoughby ◽  
Wendy Anderson
Keyword(s):  
Vegetation Structure ◽  
Prey Availability ◽  
Vegetation Type ◽  
Missouri River ◽  
Suitable Habitat ◽  
Arthropod Communities ◽  
Web Building ◽  
Emergent Insects ◽  
Rock Lake ◽  
Land Water

We investigated the distribution and abundance of terrestrial spiders as a function of their distance from a body of water and the structure of vegetation that would provide suitable habitat. We hypothesized that spiders would prefer to be located near the water to catch abundant aquatic emergent insects. In Montana along the Upper Missouri River, and in Missouri at various locations around Table Rock Lake, transect lines were run from the water’s edge to 25 meters inland. At five-meter intervals, in one square meter plots, the number of spiders, number of prey and type, and vegetation type and structure were recorded. In both Montana and Missouri, spider distribution was more strongly associated with available vegetation structure than with distance from shore. This suggests that, although prey availability may be important for predator distribution, suitable habitat is as strong or stronger a determinant for web building spiders.

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