Verifying bilby presence and the systematic sampling of wild populations using sign-based protocols – with notes on aerial and ground survey techniques and asserting absence

2019 ◽  
Vol 41 (1) ◽  
pp. 27 ◽  
Author(s):  
Richard Southgate ◽  
Martin A. Dziminski ◽  
Rachel Paltridge ◽  
Andrew Schubert ◽  
Glen Gaikhorst
Keyword(s):  
Gait Pattern ◽  
Aerial Survey ◽  
Systematic Sampling ◽  
Wild Populations ◽  
Survey Techniques ◽  
Ground Survey ◽  
Potential Activity ◽  
Elusive Species ◽  
Survey Effort ◽  
Burrow Activity

The recognition of sign such as tracks, scats, diggings or burrows is widely used to detect rare or elusive species. We describe the type of sign that can be used to confirm the presence of the greater bilby (Macrotis lagotis) in comparison with sign that should be used only to flag potential presence. Clear track imprints of the front and hind feet, diggings at the base of plants to extract root-dwelling larvae, and scats commonly found at diggings can be used individually, or in combination, to verify presence, whereas track gait pattern, diggings in the open, and burrows should be used to flag potential bilby activity but not to verify presence. A protocol to assess potential activity and verify bilby presence is provided. We provide advice on the application of a plot-based technique to systematically search for sign and produce data for the estimation of regional occupancy. Digging and burrow activity can be readily detected from the air but systematic ground-based assessment to determine the rate of false-presence and false-absence needs to accompany aerial survey. The approach to estimate survey effort to assert bilby absence is also described.

scholarly journals Mapping of Archaeological Sites using UAV Aerial Survey and PPK GNSS Ground Survey Techniques in Central Asia

2020 ◽  
Vol 540 ◽  
pp. 012014
Author(s):  
Stanley Anak Suab ◽  
Yuichi Hayakawa ◽  
Shogo Kume ◽  
Yuji Yamaguchi ◽  
Bakyt Amanbaeva ◽  
...  
Keyword(s):  
Central Asia ◽  
Aerial Survey ◽  
Archaeological Sites ◽  
Survey Techniques ◽  
Ground Survey

Aerial Survey Techniques for Locating Abandoned Strip Mine Land

1980 ◽  
Vol 9 (4) ◽  
pp. 606-610
Author(s):  
L. E. Dattavio ◽  
R. P. Mroczynski ◽  
R. A. Weismiller
Keyword(s):  
Aerial Survey ◽  
Survey Techniques ◽  
Strip Mine

A New Probabilistic Methodology for Undertaking External Corrosion Direct Assessment

2006 ◽  
Author(s):  
Andrew Francis ◽  
Marcus McCallum ◽  
Menno T. Van Os ◽  
Piet van Mastrigt
Keyword(s):  
Surface Characteristics ◽  
Survey Techniques ◽  
Direct Assessment ◽  
Ground Survey ◽  
Pressure Test ◽  
Integrity Management ◽  
Corrosion Defects ◽  
Low Probability ◽  
External Corrosion ◽  
Pipeline Safety

External Corrosion Direct Assessment (ECDA) has now become acknowledged, by the Office of Pipeline Safety (OPS) in North America, as a viable alternative to both in-line inspection (ILI) and the hydrostatic pressure test for the purpose of managing the integrity of high pressure pipelines. Accordingly an ECDA standard is now in existence. The essence of ECDA is to use indirect above ground survey techniques to locate the presence of coating and corrosion defects and then to investigate some of the indications directly by making excavations. However, one of the problems of above ground survey techniques is that they do not locate all defects and are susceptible to false indication. This means that the defects will not be present at all indications and that some defects will be missed. In view of the limitations of above ground survey techniques the ECDA standard requires that at least two complimentary survey techniques should be used. The selected survey techniques will depend on the nature of a particular ‘ECDA segment’, taking account of the surface characteristics. However, in many situations the surveys will include a coating survey and a corrosion survey. In general the outcome from these two surveys will be NH locations at which just the coating survey gives an indication, NC locations at which just the corrosion survey gives an indication and NHC locations at which both surveys give an indication. This paper presents a new probabilistic methodology for estimating the distributions of the actual numbers of coating and corrosion defects, taking account of the outcomes of the surveys and the probabilities of detection and false indication of both techniques. The method also shows how the probabilities of detection and false indication are updated depending on what is found during the excavations and the distributions of the numbers of remaining corrosion and coating defects are subsequently modified. Based on a prescribed repair criterion the analysis is used to determine the probability that at least one remaining corrosion defect will exceed the repair criteria. As excavations are sequentially performed the probability naturally reduces. The attainment of an acceptably low probability is used as a trigger to terminate the excavation programme. A detailed description of the development of the method is given in this paper and the application is illustrated through a simple numerical example. A description of how the method is used to build a Direct Assessment module for a pipeline integrity management system is described in an accompanying paper.

scholarly journals LARGE-SCALE SUBSIDENCE GEOHAZARD MONITORING WITH SENTINEL-1 SAR INTERFEROMETRY IN CENTRAL LISHUI (CHINA)

2021 ◽  
Vol XLIII-B3-2021 ◽  
pp. 873-878
Author(s):  
T. Qu ◽  
Z. Su ◽  
H. Yang ◽  
X. Shi ◽  
W. Shao
Keyword(s):  
Large Scale ◽  
Small Deformation ◽  
Sar Interferometry ◽  
Ground Subsidence ◽  
Impact Factors ◽  
Survey Techniques ◽  
Ground Survey ◽  
In Situ Sensors ◽  
Sbas Insar ◽  
Subsidence Monitoring

Abstract. Ground subsidence has become a serious problem along with the rapid urban expansions. Compared with traditional point-based ground survey techniques (GPS, levelling measurement and in-situ sensors), SAR Interferometry are quite appreciated for large-scale subsidence monitoring with long term and high accuracy. In this study, we focused on large-scale subsidence geohazard monitoring of central Lishui (China) and extracted subsidence velocity map of Liandu District. 57 Sentinle-1 SAR images from April 2019 to September 2020 are analysed with SBAS-InSAR technique. The overall subsidence of Liandu is significantly correlated with the distributions of construction engineering sites with displacement velocity of approximately 30–60 mm/yr. Various types of urban ground subsidence could be identified, including the overall settlement of large construction site, the slope deformation of construction excavation, significant settlement of refuse landfill and mountain crossing tunnel, and small deformation of highvoltage towers in mountainous areas. Our results indicated that the rapid urban developments are the dominant impact factors of subsidence in Lishui, China.

scholarly journals INTEGRATED SURVEY FOR ARCHITECTURAL RESTORATION: A METHODOLOGICAL COMPARISON OF TWO CASE STUDIES

2016 ◽  
Vol XLI-B5 ◽  
pp. 175-182
Author(s):  
G. Bianchi ◽  
N. Bruno ◽  
E. Dall’Asta ◽  
G. Forlani ◽  
C. Re ◽  
...  
Keyword(s):  
Case Studies ◽  
Laser Scanner ◽  
Aerial Survey ◽  
Survey Techniques ◽  
Levels Of Detail ◽  
Technical Advances ◽  
Close Range ◽  
Architectural Restoration ◽  
Efficiency And Productivity ◽  
Single Technique

A preliminary survey campaign is essential in projects of restoration, urban renewal, rebuilding or promotion of architectural heritage. Today several survey techniques allow full 3D object restitution and modelling that provides a richer description than simple 2D representations. However, the amount of data to collect increases dramatically and a trade-off between efficiency and productivity from one side and assuring accuracy and completeness of the results on the other must be found. Depending on the extent and the complexity of the task, a single technique or a combination of several ones might be employed. Especially when documentation at different scales and with different levels of detail are foreseen, the latter will likely be necessary. The paper describes two architectural surveys in Italy: the old village of Navelli (AQ), affected by the earthquake in 2009, and the two most relevant remains in Codiponte (MS), damaged by the earthquake in 2013, both in the context of a project of restoration and conservation. In both sites, a 3D survey was necessary to represent effectively the objects. An integrated survey campaign was performed in both cases, which consists of a GPS network as support for georeferencing, an aerial survey and a field survey made by laser scanner and close range photogrammetry. The two case studies, thanks to their peculiarities, can be taken as exemplar to wonder if the integration of different surveying techniques is today still mandatory or, considering the technical advances of each technology, it is in fact just optional.

scholarly journals INTEGRATED SURVEY FOR ARCHITECTURAL RESTORATION: A METHODOLOGICAL COMPARISON OF TWO CASE STUDIES

2016 ◽  
Vol XLI-B5 ◽  
pp. 175-182 ◽  
Author(s):  
G. Bianchi ◽  
N. Bruno ◽  
E. Dall’Asta ◽  
G. Forlani ◽  
C. Re ◽  
...  
Keyword(s):  
Case Studies ◽  
Laser Scanner ◽  
Aerial Survey ◽  
Survey Techniques ◽  
Levels Of Detail ◽  
Technical Advances ◽  
Close Range ◽  
Architectural Restoration ◽  
Efficiency And Productivity ◽  
Single Technique

A preliminary survey campaign is essential in projects of restoration, urban renewal, rebuilding or promotion of architectural heritage. Today several survey techniques allow full 3D object restitution and modelling that provides a richer description than simple 2D representations. However, the amount of data to collect increases dramatically and a trade-off between efficiency and productivity from one side and assuring accuracy and completeness of the results on the other must be found. Depending on the extent and the complexity of the task, a single technique or a combination of several ones might be employed. Especially when documentation at different scales and with different levels of detail are foreseen, the latter will likely be necessary. The paper describes two architectural surveys in Italy: the old village of Navelli (AQ), affected by the earthquake in 2009, and the two most relevant remains in Codiponte (MS), damaged by the earthquake in 2013, both in the context of a project of restoration and conservation. In both sites, a 3D survey was necessary to represent effectively the objects. An integrated survey campaign was performed in both cases, which consists of a GPS network as support for georeferencing, an aerial survey and a field survey made by laser scanner and close range photogrammetry. The two case studies, thanks to their peculiarities, can be taken as exemplar to wonder if the integration of different surveying techniques is today still mandatory or, considering the technical advances of each technology, it is in fact just optional.

A new small-bodied, polymorphic Cnemaspis Strauch, 1887 (Squamata: Gekkonidae) allied to C. monticola Manamendra-Arachchi, Batuwita & Pethiyagoda, 2007 from the Central Western Ghats of Karnataka, India

Zootaxa ◽  
2021 ◽  
Vol 4950 (3) ◽  
pp. 501-527
Author(s):  
AKSHAY KHANDEKAR ◽  
TEJAS THACKERAY ◽  
ISHAN AGARWAL
Keyword(s):  
New Species ◽  
Western Ghats ◽  
Field Survey ◽  
Small Body ◽  
Sequence Divergence ◽  
Systematic Sampling ◽  
Small Body Size ◽  
Central Western Ghats ◽  
Survey Effort ◽  
Dorsal Tubercle

We describe a new small-bodied, polymorphic Cnemaspis from near Hongadahalla village, Sakleshpur in the Central Western Ghats of Karnataka, India. Cnemaspis schalleri sp. nov. is allied to C. monticola and can be diagnosed from all other Indian Cnemaspis by its small body size; presence of spine-like tubercles on flank; heterogeneous dorsal pholidosis; presence of both precloacal and femoral pores in males; dorsal pholidosis of tail heterogeneous, composed of small, weakly keeled, flattened, sub-imbricate scales intermixed with enlarged, strongly keeled, distinctly pointed, conical tubercles forming whorls; slightly enlarged median row of sub-caudal scales, smooth at anterior half and strongly keeled posteriorly. The new species differs from C. monticola based on the number of dorsal tubercle rows at mid-body, the number of paravertebral tubercles, the number of precloacal pores and poreless scales between precloacal and femoral pores; besides 8.9–10.7 % uncorrected ND2 sequence divergence. We also provide the first description of topotypic males of C. monticola along with the first data on live colouration and natural history. Cnemaspis schalleri sp. nov. is the second new Cnemaspis described from around Sakleshpur within a span of less than a year with minimal field survey effort. It is almost certain than the dedicated systematic sampling across the Central Western Ghats will result in the discovery of many undescribed Cnemaspis lineages. 

scholarly journals Investigating the potential of opportunistic sighting data to inform wildlife conservation strategies

2016 ◽  
Author(s):  
Simone Tenan ◽  
Paolo Pedrini ◽  
Natalia Bragalanti ◽  
Claudio Groff ◽  
Chris Sutherland
Keyword(s):  
Spatial Information ◽  
Space Use ◽  
Data Sources ◽  
Conservation Strategies ◽  
Systematic Sampling ◽  
Management Actions ◽  
Sampling Protocols ◽  
Elusive Species ◽  
Scr Model ◽  
Number Of Individuals

ABSTRACTAbundance and space use are key population-level parameters used to inform management and conservation decisions of rare and elusive species, for which monitoring resources can be limited, potentially affecting quality of model-based inference. Recently-developed methods that integrate multiple data sources arising from the same ecological process have typically been focused on data from well-defined sampling protocols, i.e. structured data sets. Despite a rapid increase in availability of large datasets, the value of unstructured or opportunistic data to improve inference about spatial ecological processes is, however, unclear. Using spatial capture-recapture (SCR) methods, we jointly analyze opportunistic recovery of biological samples, traditional SCR data resulting from systematic sampling of hair traps and rub trees, and satellite telemetry data, collected on a reintroduced brown bear population in the central Alps. We compared the precision of sex-specific estimates of density and space use derived from models using combinations of data sources ranging from traditional SCR to a fully integrated SCR model that includes both telemetry and opportunistic data. Estimates of density and space use were more precise when unstructured data were added compared to estimates from a classical SCR model. Our results demonstrate that citizen science data lend itself naturally to integration with in the SCR framework and highlight the value of opportunistic data for improving inference about space use, and in turn, of abundance and density. When individual identity and location can be obtained from opportunistic observations, such data are informative about space use and thus have the potential to improve estimates of movement and density using SCR methods. This is particularly relevant in studies of rare or elusive species, where the amount of SCR encounters is usually small, but also budget restrictions and the difficulty of collaring animals limit the number of individuals for which telemetry information is available. Spatially-referenced opportunistic data thus potentially increase both the geographic extent of a study and the number of individuals with available spatial information, providing an improved understanding of how individuals are distributed and how they use space – fundamental components for calibrating conservation management actions.

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