scholarly journals An investigation of urban bat ecology in Baltimore, Maryland

2019 ◽  
Author(s):  
◽  
Ela Sita Carpenter
Keyword(s):  
Species Richness ◽  
Census Data ◽  
Urban Landscape ◽  
Acoustic Monitoring ◽  
Activity Levels ◽  
Baltimore County ◽  
Vacant Lots ◽  
Bat Activity ◽  
Socioeconomic Variables ◽  
Neighborhood Scale

In North America, bats are a taxon of concern that play an important role in insect control, and their response to urbanization varies. I wanted to discover if evaluating environmental and socioeconomic variables present in an urban landscape can help determine what bat species were present and how active these species were. Research occurred in Baltimore, Maryland, a 'shrinking' city in the eastern US, which had no prior research on the bat community. For my first project, I used active acoustic monitoring to evaluate how bat activity levels (amount of detected acoustic sequences) and the bat community varied along both a direct and indirect rural to urban gradient. Nine sites along the Gwynns Falls watershed in Baltimore County and City were used the gradient. Over 1,500 sequences (detection files) were recorded from six species and I found that the direct and indirect measures of urbanization gradient used are not a predictor of bat presence and activity. For my next project I used passive acoustic monitoring to record bat activity at 32 vacant lots within Baltimore City to determine which environmental and socioeconomic variables best predict bat species richness and activity at these small, informal, understudied urban greenspaces. Environmental and socioeconomic data was obtained using on-site measures, GIS, and US Census data. There were no predictors for overall species richness. Canopy-associated measures at both the site and neighborhood scale, streetlights, site distance from water and the urban core, residential race and income, old housing, and rental housing were all common predictors of bat species' activity levels. Species relationships with these predictors varied and some species had additional predictors, suggesting that bats use the urban landscape to different degrees. Some larger lots could potentially be managed to have vegetation structural complexity (allowing both canopy cover and open space to accommodate bat species with different traits), but many lots are too small to do this. Vacant lots closer to water and larger patches of forests have the most potential to be managed for bats.

scholarly journals Simultaneous acoustic monitoring uncovers evidence of biodiversity loss and overlooked temporal variation in a threatened Amazonian bird community

2021 ◽  
Author(s):  
W. Alexander Hopping ◽  
Holger Klinck
Keyword(s):  
Species Richness ◽  
Temporal Variation ◽  
Amazon Basin ◽  
Bird Community ◽  
Acoustic Monitoring ◽  
Avian Species ◽  
Activity Levels ◽  
Generalist Species ◽  
Vocal Activity ◽  
Interior Forest

Birds are frequently used as indicator taxon in ecology, but traditional surveys are prone to error and largely inadequate in the dense, speciose tropical forests where they are most needed. Passive acoustic monitoring (PAM) has the potential to address many of these pitfalls, providing unique advantages for both long-term monitoring and rapid biodiversity assessment. Here, we evaluate the effectiveness of PAM for characterizing spatiotemporal variation in avian species richness, diversity, vocal activity, and community composition in the Amazon basin global biodiversity hotspot. We employed an array of ten autonomous recording units (ARUs) spanning edge, degraded, and interior forest at a reserve on the deforestation frontier of Madre de Dios, Peru, a region featuring some of the richest, most complex avian assemblages on Earth. Recordings from 21 dawn-hours across three days at seven sites were manually annotated by a single observer. ARUs and manual annotation performed well as an inventory method, especially for midstory and understory species. Sites in edge and degraded habitats featured significantly lower avian species richness, Shannon diversity, and vocal activity levels than in the forest interior, patterns that replicate the findings of prior high-effort avian censuses in the region. We observed significant temporal variation between days; at all featured sites, vocal activity was highest on January 20th and lowest on January 31st. We demonstrated that novel annotation-generated metrics can work as effective proxies for abundance data and per-capita song rate, correlating with diversity indices and efficiently characterizing habitats at a level of detail unobtainable with human observers. Generalist species were significantly overrepresented in the soundscapes of interior forest, relative to their contributed share of species richness, and interior specialists were underrepresented, suggesting that the entire 191ha site is degraded. The between-days temporal variation that we documented, almost certainly overlooked without simultaneous monitoring, may obfuscate or distort the results of traditional surveys. Synthesis & Applications. We propose that PAM should become a cornerstone of biodiversity research. The standardization advantages demonstrated in this study, permanent storage, multi-taxa applications, and potential of automated identification make bioacoustics an ideal methodological avenue for guiding management and policy under rapid global change.

How high is high? Using percentile thresholds to identify peak bat activity

2015 ◽  
Vol 93 (4) ◽  
pp. 307-313 ◽  
Author(s):  
Amanda M. Adams ◽  
Liam P. McGuire ◽  
Lauren A. Hooton ◽  
M. Brock Fenton
Keyword(s):  
Specific Activity ◽  
Activity Patterns ◽  
Acoustic Monitoring ◽  
Activity Levels ◽  
Peak Activity ◽  
Passive Acoustic Monitoring ◽  
Data Set ◽  
Bat Activity ◽  
Species Specific ◽  
Passive Acoustic

Passive acoustic monitoring is a common tool used for monitoring bat activity levels. Identifying periods and locations of peak levels provides insight into bat ecology and has important management implications. One limitation of passive acoustic monitoring is the relative nature of the data, often relying on subjective interpretation of descriptive terminology such as “higher” or “lower”. We propose the use of percentile thresholds (PTs) for objectively identifying peak activity. By compiling a reference data set, it is possible to define percentiles of the observed activity levels and these percentiles can provide objective thresholds for comparing activity levels. We used acoustic recordings from sites in Canada and calculated PTs based on the distribution of the number of calls per hour across all nights and sites for three species of bat. Given species ecologies (e.g., hibernating, migrating), we were able to use PTs to objectively identify peak activity levels on a species-specific basis. Percentile thresholds are also a replicable method of describing within-night activity by evaluating species-specific activity patterns and important times of night. Our analyses and examples represent a proof of concept. The next step is to move towards a standardized distribution to generate PTs. Creating a public repository of acoustic data sets to evaluate activity of a species in the context of its entire range would allow us to standardize terms such as “high” activity in an objective manner.

scholarly journals Planning for a neighborhood and city-scale green network system in Qatar: the case of MIA Park

2021 ◽  
Author(s):  
Raffaello Furlan ◽  
Brian R. Sinclair
Keyword(s):  
Urban Landscape ◽  
Single Case ◽  
Landscape Fragmentation ◽  
The State ◽  
Network System ◽  
Design Strategies ◽  
Structured Interviews ◽  
Main Mode ◽  
The Past ◽  
Neighborhood Scale

AbstractIn the past decade, Doha has witnessed fast-urban growth, an increased population rate, and an over-reliance on the automobile as the main mode of urban transportation. These factors caused social and environmental problems related to (1) the loss of a compact urban pattern, (2) an increased level of air pollution (3) high traffic congestions and (4) increasing landscape fragmentation. In consideration of such concerns, The State of Qatar invested large funds into the urban landscape development of Doha, as envisioned by Qatar National Vision 2030. As a result, in the past five years various parks and/or green areas, such MIA Park, a major public green space located around the Museum of Islamic Art (MIA), were planned and developed within metropolitan Doha. The authors argue that this park is currently facing issues and challenges related to (1) accessibility to/from the neighboring districts, and (2) connectivity to/from the neighboring parks. Therefore, this research study aims at assessing the existing conditions of MIA Park, at considering the broader city context and, at recommending strategies for implementing MIA Park’s green network system. It approached the investigative challenge using a multi-pronged comprehensive methodology, that deployed focus groups, semi-structured interviews and a comprehensive network analysis based on graph theory. The findings, revealed through these hybrid research tactics, allowed the researchers to generate a framework to enhance accessibility and connectivity of MIA Park through a green network system, planned at inter-related neighborhood-scale and city-scale levels. While the research examines most notably a single case, it is advocated that the proposed framework represents not just an optional feature pertaining to the case in Doha, but a valuable reference for the sustainable master planning of future cities in the State of Qatar and across the GCC. The paper proffers numerous key contributions, including the critical exploration of manufactured landscapes in Doha Qatar and the delineation of broadly applicable environmental design strategies to improve the fabric and livability of cities.

Canopy and edge activity of bats in a quaking aspen (Populus tremuloides) forest

2012 ◽  
Vol 90 (7) ◽  
pp. 798-807 ◽  
Author(s):  
T.W. Pettit ◽  
K.T. Wilkins
Keyword(s):  
Populus Tremuloides ◽  
High Frequency ◽  
Regression Tree ◽  
Low Frequency ◽  
Tree Height ◽  
Quaking Aspen ◽  
Activity Levels ◽  
Forest Canopies ◽  
Bat Activity ◽  
Cart Analysis

Characteristics of edges affect the behavior of species that are active in and near edges. Forest canopies may provide edge-like habitat for bats, though bat response to edge orientation has not been well examined. We sampled bat activity in quaking aspen ( Populus tremuloides Michx.) forest canopies and edges in Heber Valley, Utah, during summer 2009 using Anabat detectors. Categorization and regression tree (CART) analysis of echolocation characteristics (e.g., frequency, duration) identified two guilds based on characteristic frequency (i.e., high- and low-frequency guilds). We used linear regression to compare characteristics of canopy and edge vegetation (e.g., tree height, diameter at breast height) to bat activity levels. Activity levels of high-frequency bats did not respond differentially to edge vegetation; low-frequency bat activity seemed to respond to canopy height. Activity levels of high-frequency bats were significantly greater than low-frequency bats in both edges and canopies. We detected significantly more bat activity in forest edges than in forest canopies, indicating the importance of edges to bats in forests.

scholarly journals Study on Urban Landscape Green Space -- A Case Study of Longquanshan Park

2021 ◽  
Vol 272 ◽  
pp. 01002
Author(s):  
Huan Dai ◽  
Wei Li ◽  
Yan Zeng ◽  
Xinyang Zhang
Keyword(s):  
Species Richness ◽  
Urban Landscape ◽  
Diversity Index ◽  
Evergreen Species ◽  
Forest Park ◽  
Shrub Layer ◽  
Tree Layer ◽  
Deciduous Shrubs ◽  
Forest Parks ◽  
Richness Index

Studying on Qinglongshan Forest Park in Wuhan by typical plot method, 15 typical plots in the park were investigated, and the species richness index, diversity index, evenness index, frequency and important value index were calculated. The results showed that there were 139 species of woody plants belonging to 46 families and 97 genera, including 41 species of evergreen trees, 32 species of deciduous trees, 62 species of evergreen shrubs, 25 species of deciduous shrubs, and 4 species of bamboo belonging to 1 family, 3 genera. Species richness index and Simpson diversity index were all expressed as tree layer > shrub layer, evergreen species > deciduous species. Pielou evenness was tree layer > shrub layer. This study can provide some reference for understanding the existing plant status of forest parks, carrying out science popularization, scientific research, protection and improvement of forest landscape quality.

scholarly journals Urban Nighttime Leisure Space Mapping with Nighttime Light Images and POI Data

2020 ◽  
Vol 12 (3) ◽  
pp. 541 ◽  
Author(s):  
Jiping Liu ◽  
Yue Deng ◽  
Yong Wang ◽  
Haosheng Huang ◽  
Qingyun Du ◽  
...  
Keyword(s):  
Urban Area ◽  
Census Data ◽  
Leisure Activities ◽  
Social Activity ◽  
Activity Levels ◽  
Social Functions ◽  
The Social ◽  
Nighttime Light ◽  
The Government ◽  
Physical Features

Urban nighttime leisure spaces (UNLSs), important urban sites of nighttime economic activity, have created enormous economic and social benefits. Both the physical features (e.g., location, shape, and area) and the social functions (e.g., commercial streets, office buildings, and entertainment venues) of UNLSs are important in UNLS mapping. However, most studies rely solely on census data or nighttime light (NTL) images to map the physical features of UNLSs, which limits UNLS mapping, and few studies perform UNLS mapping from a social function perspective. Point-of-interest (POI) data, which can reflect social activity functions, are needed. As a result, a novel methodological UNLS mapping framework, that integrates NTL images and POI data is required. Consequently, we first extracted high-NTL intensity and high-POI density areas from composite data as areas with high nightlife activity levels. Then, the POI data were analyzed to identify the social functions of leisure spaces revealing that nighttime leisure activities are not abundant in Beijing overall, the total UNLS area in Beijing is 31.08 km2, which accounts for only 0.2% of the total area of Beijing. In addition, the nightlife activities in the central urban area are more abundant than those in the suburbs. The main urban area has the largest UNLS area. Compared with the nightlife landmarks in Beijing established by the government, our results provide more details on the spatial pattern of nighttime leisure activities throughout the city. Our study aims to provide new insights into how multisource data can be leveraged for UNLS mapping to enable researchers to broaden their study scope. This investigation can also help government departments better understand the local nightlife situation to rationally formulate planning and adjustment measures.

Seasonal Activity Patterns of Two Species of Nyctophilus Bats Based on Mist-Net Captures.

1998 ◽  
Vol 20 (3) ◽  
pp. 349
Author(s):  
R.M. Brigham ◽  
F. Geiser
Keyword(s):  
Activity Patterns ◽  
Activity Cycle ◽  
Activity Levels ◽  
Seasonal Activity ◽  
Daily Torpor ◽  
Bat Activity ◽  
Annual Activity ◽  
A Site ◽  
Mist Net

We evaluated the annual activity cycle of Nytophilus gouldi and N. geoffroyi using 82 nights of mist-netting data from a site near Armidale in northern NSW. Our purpose was to assess whether these bats hibernated or used short bouts of daily torpor combined with foraging on at least some nights. During the cold months of the year (May - August) bat activity levels inferred from net captures was very low providing support for the hypothesis that these bats use daily torpor and at least sometimes actively forage as opposed to entering hibernation.

Insights into airplane overflight effects on bioacoustic activity levels from long-term acoustic monitoring

2016 ◽  
Vol 139 (4) ◽  
pp. 2090-2090
Author(s):  
Susan Parks ◽  
Samuel L. Denes ◽  
Leanna P. Matthews ◽  
Pramod K. Varshney ◽  
Kurt M. Fristrup
Keyword(s):  
Acoustic Monitoring ◽  
Activity Levels

Concentration of bat activity in riparian habitats over an elevational gradient

1999 ◽  
Vol 77 (6) ◽  
pp. 972-977 ◽  
Author(s):  
S D Grindal ◽  
J L Morissette ◽  
R M Brigham
Keyword(s):  
Elevational Gradient ◽  
Relative Activity ◽  
Activity Levels ◽  
Riparian Areas ◽  
Habitat Types ◽  
Bat Activity ◽  
Prey Resources ◽  
Riparian Habitats ◽  
Mist Net ◽  
Capture Rates

Riparian areas are generally assumed to represent important foraging areas for insectivorous bats, but this contention has rarely been formally quantified. To test this assumption, we used bat detectors to compare the relative activity levels of a community of temperate-zone bat species between riparian (lake) and upland (cutblock) habitats at three different elevations (ranging from 540 to 1800 m) in a forested area of southern British Columbia. In addition, we also investigated the sex and age class distributions of bats (based on mist-net captures) between riparian and upland habitats among the elevational zones. Bat activity levels were significantly greater in riparian than upland areas (10 and 40 times greater for foraging and commuting activity, respectively). Capture rates were greater in riparian areas and biased towards females, suggesting that female bats may preferentially select riparian areas, probably because of the abundant prey resources typically associated with this habitat. Captures of females also predominated at lower elevations, whereas males were captured more often in higher elevation zones. Our data support the assumption that riparian habitats represent important foraging and probably drinking areas for bats. The sex bias and differences in capture rates and activity levels need to be considered when designing bat surveys in different habitat types or over elevational gradients.

Sign in / Sign up

Export Citation Format

Share Document