scholarly journals Validating the use of stereo‐video cameras to conduct remote measurements of sea turtles

2021 ◽  
Author(s):  
Tabitha R. Siegfried ◽  
Mariana M. P. B. Fuentes ◽  
Matthew Ware ◽  
Nathan J. Robinson ◽  
Emma Roberto ◽  
...  
Keyword(s):  
Sea Turtles ◽  
Video Cameras ◽  
Stereo Video ◽  
Remote Measurements

scholarly journals Insights Into Sea Turtle Population Composition Obtained With Stereo-Video Cameras in situ Across Nearshore Habitats in the Northeastern Gulf of Mexico

2021 ◽  
Vol 8 ◽  
Author(s):  
Tabitha Siegfried ◽  
Christopher Noren ◽  
Jackson Reimer ◽  
Matthew Ware ◽  
Mariana M. P. B. Fuentes ◽  
...  
Keyword(s):  
Gulf Of Mexico ◽  
Sea Turtles ◽  
Sea Turtle ◽  
Life Stages ◽  
Turtle Species ◽  
Stereo Video ◽  
Population Size Estimates ◽  
Turtle Population ◽  
Northeastern Gulf Of Mexico

Population size estimates are key parameters used in assessments to evaluate and determine a species’ conservation status. Typically, sea turtle population estimates are made from nesting beach surveys which capture only hatchling and adult female life stages and can display trends opposite of the full population. As such, in-water studies are critical to improve our understanding of sea turtle population dynamics as they can target a broader range of life stages – though they are more logistically and financially challenging to execute compared to beach-based surveys. Stereo-video camera systems (SVCS) hold promise for improving in-water assessments by removing the need to physically capture individuals and instead extract 3D measurements from video footage, thereby simplifying monitoring logistics and improving safety for the animals and surveyors. To demonstrate this potential, snorkel surveys were conducted at artificial habitats in the northeastern Gulf of Mexico (neGOM) to collect size and photo-identification data on sea turtles in situ using a SVCS. Over 29.86 survey hours, 35 sea turtles were observed across three species (Caretta caretta, Chelonia mydas, and Lepidochelys kempii) and all neritic life stages (juvenile, sub-adult, and adult) utilizing different habitats, including artificial reefs, jetties, and fishing piers. Greens straight carapace length ranged from 28.55 to 66.96 cm (n = 23, mean 43.07 cm ± 11.26 cm standard deviation; SD) and loggerheads ranged from 59.71 to 91.77 cm (n = 10, mean 74.50 cm ± 11.35 cm SD), and Kemp’s ridleys ranged from 42.23 cm to 44.98 cm (mean 43.61 cm ± 1.94 cm SD). Using a linear mixed model, we found that species and habitat type were the most important predictors of sea turtle body length distribution. Overall, this case study demonstrates the potential of SVCS surveys to enhance our understanding of the population structure of sea turtle species within the neGOM and elsewhere.

Improved 3-D reconstruction using stereo computer graphics and multiple tilt EM images

1995 ◽  
Vol 53 ◽  
pp. 630-631
Author(s):  
Lee D. Peachey ◽  
Lou Fodor ◽  
John C. Haselgrove ◽  
Stanley M. Dunn ◽  
Junqing Huang
Keyword(s):  
Computer Graphics ◽  
High Performance ◽  
Transverse Section ◽  
Three Dimensional ◽  
Stereo Pair ◽  
3D Reconstructions ◽  
Video Cameras ◽  
Biological Objects ◽  
Microscope Images ◽  
High Performance Computer

Stereo pairs of electron microscope images provide valuable visual impressions of the three-dimensional nature of specimens, including biological objects. Beyond this one seeks quantitatively accurate models and measurements of the three dimensional positions and sizes of structures in the specimen. In our laboratory, we have sought to combine high resolution video cameras with high performance computer graphics systems to improve both the ease of building 3D reconstructions and the accuracy of 3D measurements, by using multiple tilt images of the same specimen tilted over a wider range of angles than can be viewed stereoscopically. Ultimately we also wish to automate the reconstruction and measurement process, and have initiated work in that direction.Figure 1 is a stereo pair of 400 kV images from a 1 micrometer thick transverse section of frog skeletal muscle stained with the Golgi stain. This stain selectively increases the density of the transverse tubular network in these muscle cells, and it is this network that we reconstruct in this example.

2D Color-Intensity Representation of Ultrasonic Thickness Gauge Measurements

2020 ◽  
pp. 1192-1198
Author(s):  
M.S. Mohammad ◽  
Tibebe Tesfaye ◽  
Kim Ki-Seong
Keyword(s):  
Cost Effective ◽  
The Other ◽  
Thickness Gauge ◽  
Color Intensity ◽  
Digital Readout ◽  
Flat Surfaces ◽  
Video Cameras ◽  
Wide Range ◽  
Cost Effective Alternative ◽  
Ultrasonic Thickness

Ultrasonic thickness gauges are easy to operate and reliable, and can be used to measure a wide range of thicknesses and inspect all engineering materials. Supplementing the simple ultrasonic thickness gauges that present results in either a digital readout or as an A-scan with systems that enable correlating the measured values to their positions on the inspected surface to produce a two-dimensional (2D) thickness representation can extend their benefits and provide a cost-effective alternative to expensive advanced C-scan machines. In previous work, the authors introduced a system for the positioning and mapping of the values measured by the ultrasonic thickness gauges and flaw detectors (Tesfaye et al. 2019). The system is an alternative to the systems that use mechanical scanners, encoders, and sophisticated UT machines. It used a camera to record the probe’s movement and a projected laser grid obtained by a laser pattern generator to locate the probe on the inspected surface. In this paper, a novel system is proposed to be applied to flat surfaces, in addition to overcoming the other limitations posed due to the use of the laser projection. The proposed system uses two video cameras, one to monitor the probe’s movement on the inspected surface and the other to capture the corresponding digital readout of the thickness gauge. The acquired images of the probe’s position and thickness gauge readout are processed to plot the measured data in a 2D color-coded map. The system is meant to be simpler and more effective than the previous development.

Presence of chelonid herpesvirus 5 (ChHV5) in sea turtles in northern Sinaloa, Mexico

2019 ◽  
Vol 132 (2) ◽  
pp. 99-108
Author(s):  
RY Mejía-Radillo ◽  
AA Zavala-Norzagaray ◽  
JA Chávez-Medina ◽  
AA Aguirre ◽  
CM Escobedo-Bonilla
Keyword(s):  
Sea Turtles

I3S Pattern as a mark-recapture tool to identify captured and free-swimming sea turtles: an assessment

2018 ◽  
Vol 589 ◽  
pp. 263-268 ◽  
Author(s):  
B Calmanovici ◽  
D Waayers ◽  
J Reisser ◽  
J Clifton ◽  
M Proietti
Keyword(s):  
Sea Turtles ◽  
Free Swimming ◽  
Mark Recapture

Can Video Cameras Decrease Human Intrusion into a Closed Natural Area?

2020 ◽  
Vol 40 (3) ◽  
Author(s):  
Elizabeth A. Forys ◽  
Paul Hindsley ◽  
Maggie P. Miller ◽  
James B. Wilson ◽  
Lorraine N. Margeson ◽  
...  
Keyword(s):  
Natural Area ◽  
Video Cameras
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