The relationship between echolocation-call frequency and moth predation of a tropical bat fauna

2006 ◽  
Vol 84 (3) ◽  
pp. 425-433 ◽  
Author(s):  
C R Pavey ◽  
C J Burwell ◽  
D J Milne
Keyword(s):  
Peak Frequency ◽  
Light Traps ◽  
Echolocation Call ◽  
Constant Frequency ◽  
Low Intensity ◽  
High Duty Cycle ◽  
Strong Positive Relationship ◽  
Tropical Australia ◽  
Hearing Range ◽  
The Relationship

The allotonic frequency hypothesis proposes that the proportion of eared moths in the diet should be highest in bats whose echolocation calls are dominated by frequencies outside the optimum hearing range of moths i.e., <20 and >60 kHz. The hypothesis was tested on an ecologically diverse bat assemblage in northern tropical Australia that consisted of 23 species (5 families, 14 genera). Peak frequency of signals of bats within the echolocation assemblage ranged from 19.8 to 157 kHz but was greatest between 20 and 50 kHz. A strong positive relationship existed between peak call frequency and percentage of moths in the diet for a sample of 16 bats from the assemblage representing 13 genera (R2 = 0.54, p = 0.001). The relationship remained strong when the three species with low-intensity calls were excluded. When the two species with high duty cycle, constant-frequency signals were removed, the relationship was weaker but still significant. In contrast to previous research, eared moths constituted only 54% of moth captures in light traps at bat foraging grounds, and eared moths were significantly larger than non-eared individuals. These results show that the pattern of moth predation by tropical bats is similar to that already established for bat faunas in subtropical and temperate regions.

scholarly journals Unusual echolocation behaviour of the common sword-nosed bat Lonchorhina aurita : an adaptation to aerial insectivory in a phyllostomid bat?

2019 ◽  
Vol 6 (7) ◽  
pp. 182165 ◽  
Author(s):  
Gloria Gessinger ◽  
Tania P. Gonzalez-Terrazas ◽  
Rachel A. Page ◽  
Kirsten Jung ◽  
Marco Tschapka
Keyword(s):  
Peak Frequency ◽  
Terminal Group ◽  
Echolocation Call ◽  
Constant Frequency ◽  
Cluttered Environments ◽  
Echolocation Calls ◽  
The Common ◽  
Hunting Mode ◽  
First Time ◽  
Down Sweep

Most insectivorous bat species in the Neotropical family Phyllostomidae glean insects from ground, water or vegetation surfaces. They use similar and stereotypical echolocation calls that are generally very short (less than 1–3 ms), multi-harmonic and frequency-modulated (FM). By contrast, the common sword-nosed bat, Lonchorhina aurita , which has the longest noseleaf in the entire phyllostomid family, produces distinctly different echolocation calls. They are composed of a constant frequency (CF) component with a peak frequency of 45 kHz, followed by a short FM down-sweep at the end. With a mean call duration of 6.6 ms (max. 8.7 ms) when flying in the open they have the longest echolocation calls reported from phyllostomid bats. In cluttered environments, the CF-component is very short. In open habitats, however, L. aurita can emit pure CF-calls without the terminal FM-component. We also recorded in the field a distinct terminal group that closely resembles the feeding buzzes of aerial hawking bat species from other bat families. This is the first time the echolocation call design of L. aurita is presented. In addition, we contrast the echolocation behaviour of individuals flying in open and confined situations. Our results suggest that the unique echolocation system of L. aurita represents an adaptation to aerial hawking, a very unusual hunting mode within the phyllostomid family.

Echolocation call structure and intensity in five species of insectivorous bats.

1995 ◽  
Vol 198 (2) ◽  
pp. 475-489 ◽  
Author(s):  
D A Waters ◽  
G Jones
Keyword(s):  
Energy Flux ◽  
Escape Response ◽  
Free Flight ◽  
Echolocation Call ◽  
Constant Frequency ◽  
Insectivorous Bats ◽  
Call Structure ◽  
Low Intensity ◽  
Energy Flux Density ◽  
Rms Amplitude

Echolocation call intensity was measured in the laboratory for five species of British insectivorous bats in free flight and in the hand. All species showed similar call intensities of between 80 and 90 dB peSPL (peak equivalent SPL) at 1 m during flight except Plecotus auritus, whose call intensity was between 68 and 77 dB peSPL at 1 m. Calls from stationary bats were about 13 dB less intense than calls during flight. A method is proposed to measure the root mean square (rms) amplitude of echolocation calls and, hence, to calculate the energy flux density of the call. The constant-frequency calls of Rhinolophus hipposideros have energy flux densities approximately ten times higher than those of bats using frequency-modulated calls as a result of their longer durations and lower crest factors. It is argued that the low-intensity calls of P. auritus allow it to approach tympanate moths more closely before triggering their escape response.

EL NINO RELATED CLIMATE AND DENGUE FEVER CASES IN JEDDAH, SAUDI ARABIA

2019 ◽  
Vol 25 (1) ◽  
Author(s):  
MASROOR ALI KHAN ◽  
KHALID AL GHAMDI ◽  
JAZEM A. MEHYOUB ◽  
RAKHSHAN KHAN
Keyword(s):  
Relative Humidity ◽  
Dengue Fever ◽  
El Niño ◽  
Significant Relationship ◽  
El Nino ◽  
Climate Data ◽  
Light Traps ◽  
Mosquito Abundance ◽  
Dengue Transmission ◽  
The Relationship

The focus of this study is to find the relationship between El Nino and dengue fever cases in the study area.Mosquito density was recorded with the help of light traps and through aspirators collection. Climate data were obtained from National Meteorology and Environment centre. (Year wise El Nino and La Nina data are according to NOAA & Golden Gate Weather Services). Statistical methods were used to establish the correlation coefficient between different factors. A high significant relationship was observed between Relative Humidity and Dengue fever cases, but Aedes abundance had no significant relationship with either Relative humidity and Temperature. Our conclusion is that the El Nino does not affect the dengue transmission and Aedes mosquito abundance in this region, which is supported by earlier works.

INTERCONNECTION OF SUSTAINABLE DEVELOPMENT COMPONENTS FOR THE INDIGENOUS PEOPLES OF THE NORTH

2020 ◽  
Vol 2 (8) ◽  
pp. 101-110
Author(s):  
N. N. ILYSHEVA ◽  
◽  
E. V. KARANINA ◽  
G. P. LEDKOV ◽  
E. V. BALDESKU ◽  
...  
Keyword(s):  
Climate Change ◽  
Sustainable Development ◽  
Economic Development ◽  
Indigenous Peoples ◽  
Ecological Footprint ◽  
Positive Relationship ◽  
The North ◽  
Strong Positive Relationship ◽  
The Face ◽  
The Relationship

The article deals with the problem of achieving sustainable development. The purpose of this study is to reveal the relationship between the components of sustainable development, taking into account the involvement of indigenous peoples in nature conservation. Climate change makes achieving sustainable development more difficult. Indigenous peoples are the first to feel the effects of climate change and play an important role in the environmental monitoring of their places of residence. The natural environment is the basis of life for indigenous peoples, and biological resources are the main source of food security. In the future, the importance of bioresources will increase, which is why economic development cannot be considered independently. It is assumed that the components of resilience are interrelated and influence each other. To identify this relationship, a model for the correlation of sustainable development components was developed. The model is based on the methods of correlation analysis and allows to determine the tightness of the relationship between economic development and its ecological footprint in the face of climate change. The correlation model was tested on the statistical materials of state reports on the environmental situation in the Khanty-Mansiysk Autonomous Okrug – Yugra. The approbation revealed a strong positive relationship between two components of sustainable development of the region: economy and ecology.

Influence of the Intestinal Microbiota on Diabetes Management

2020 ◽  
Vol 21 (15) ◽  
pp. 1603-1615
Author(s):  
Eva Alvarez-Vieites ◽  
Arora López-Santamarina ◽  
José M. Miranda ◽  
Alicia del Carmen Mondragón ◽  
Alexandre Lamas ◽  
...  
Keyword(s):  
Immune System ◽  
Intestinal Microbiota ◽  
Diabetes Management ◽  
Scientific Evidence ◽  
Focused Attention ◽  
Economic Implications ◽  
Experimental Animals ◽  
Low Intensity ◽  
New Treatments ◽  
The Relationship

In recent decades, there has been a very rapid increase in the prevalence of diabetes globally, with serious health and economic implications. Although today there are several therapeutic treatments for this disease, these do not address the causes of the disease and have serious side effects, so it is necessary to seek new treatments to replace or complement the existing ones. Among these complementary treatments, a strong link between the intestinal microbiota and diabetes has been demonstrated, which has focused attention on the use of biotherapy to regulate the function of the intestinal microbiota and, thus, treat diabetes. In this way, the main objective of this work is to provide a review of the latest scientific evidence on diabetes, gathering information about new trends in its management, and especially, the influence of the intestinal microbiota and microbiome on this pathology. It is possible to conclude that the relationship between the intestinal microbiota and diabetes is carried out through alterations in energy metabolism, the immune system, changes in intestinal permeability, and a state of low-intensity systemic inflammation. Although, currently, most of the experimental work, using probiotics for diabetes management, has been done on experimental animals, the results obtained are promising. Thus, the modification of the microbiota through biotherapy has shown to improve the symptoms and severity of diabetes through various mechanisms related to these alterations.

Examining the Influence of Development Patterns on Flood Damages along the Gulf of Mexico

2011 ◽  
Vol 31 (4) ◽  
pp. 438-448 ◽  
Author(s):  
Samuel D. Brody ◽  
Joshua Gunn ◽  
Walter Peacock ◽  
Wesley E. Highfield
Keyword(s):  
Community Development ◽  
Gulf Of Mexico ◽  
Open Space ◽  
Property Damage ◽  
Development Patterns ◽  
Low Intensity ◽  
Flood Loss ◽  
Resilient Communities ◽  
Flood Damages ◽  
The Relationship

The rising cost of floods is increasingly attributed to the pattern and form of the built environment. Our study empirically tests this notion by examining the relationship between development intensity and property damage caused by floods. We examine five years of insured flood loss claims across 144 counties and parishes fringing the Gulf of Mexico. Results indicate that clustered, high-intensity development patterns significantly reduce amounts of reported property damage, while increasing percentages of sprawling, low-intensity development involving recent conversion of open space greatly exacerbate flood losses. These findings demonstrate the importance of community development design in fostering flood-resilient communities.

Career Plateau and Turnover Intention in Chinese Employees: Career Anchor as Moderator

2015 ◽  
Vol 43 (5) ◽  
pp. 757-766 ◽  
Author(s):  
Yueran Wen ◽  
Liu Liu
Keyword(s):  
Turnover Intention ◽  
Positive Relationship ◽  
Management Practices ◽  
Career Anchor ◽  
Career Plateau ◽  
Strong Positive Relationship ◽  
High Level ◽  
The Relationship ◽  
Moderating Role

Based on a survey of 147 Chinese employees, we examined the relationship between perceived career plateau and turnover intention, and the moderating role of career anchor in challenge in this process. We hypothesized that perceived career plateau would be positively related to turnover intention, and that this relationship would be stronger in employees with a higher level of career anchor in challenge than in those with a lower level. The results showed that perceived career plateau had a strong positive relationship with turnover intention, especially in employees with a high level of career anchor in challenge. These findings have implications for research in career development and turnover intention, as well as in management practices.

scholarly journals Pup ultrasonic isolation calls of six gerbil species and the relationship between acoustic traits and body size

2021 ◽  
Vol 8 (3) ◽  
pp. 201558
Author(s):  
Julia D. Kozhevnikova ◽  
Ilya A. Volodin ◽  
Alexandra S. Zaytseva ◽  
Olga G. Ilchenko ◽  
Elena V. Volodina
Keyword(s):  
Body Size ◽  
Discriminant Analysis ◽  
Peak Frequency ◽  
Meriones Unguiculatus ◽  
Similar Relationship ◽  
Species Identity ◽  
Call Duration ◽  
Acoustic Adaptation ◽  
Ultrasonic Calls ◽  
The Relationship

Among Gerbillinae rodents, ultrasonic calls of adults of small-sized species are typically higher frequency than those of adults of large-sized species. This study investigates whether a similar relationship can be found in pups of six gerbil species ( Dipodillus campestris , Gerbillus perpallidus , Meriones unguiculatus , Meriones vinogradovi , Sekeetamys calurus and Pachyuromys duprasi ). We compared the average values of acoustic variables (duration, fundamental and peak frequency) of ultrasonic calls (20 calls per pup, 1200 in total) recorded from 6- to 10-day-old pups (10 pups per species, 60 in total) isolated for 2 min at 22°C and then weighed and measured for body variables. The longest calls (56 ± 33 ms) were found in the largest species, and the highest frequency calls (74.8 ± 5.59 kHz) were found in the smallest species. However, across species, call duration (ranging from 56 to 159 ms among species) did not display a significant relationship with pup body size; and, among frequency variables, only the minimum fundamental frequency depended on pup body size. Discriminant analysis assigned 100% of calls to the correct species. The effect of species identity on the acoustics was stronger than the effect of body size. We discuss these results with the hypotheses of acoustic adaptation, social complexity, hearing ranges and phylogeny.

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