Limits...
Coral Reef Surveillance: Infrared-Sensitive Video Surveillance Technology as a New Tool for Diurnal and Nocturnal Long-Term Field Observations.

Dirnwoeber M, Machan R, Herler J - Remote Sens (Basel) (2012)

Bottom Line: Integrating this easy-to-set up and portable remote-sensing equipment into coral reef research is expected to significantly advance our understanding of fine-scaled biotic processes on coral reefs.The options and equipment choices in IR-sensitive surveillance technology are numerous and subject to a steadily increasing technical supply and quality at decreasing prices.Accompanied by short video examples, this report introduces a radio-transmission system for simultaneous recordings and real-time monitoring of multiple cameras with synchronized timestamps, and a surface-independent underwater-recording system.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Integrative Zoology, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria; juergen.herler@univie.ac.at.

ABSTRACT
Direct field observations of fine-scaled biological processes and interactions of the benthic community of corals and associated reef organisms (e.g., feeding, reproduction, mutualistic or agonistic behavior, behavioral responses to changing abiotic factors) usually involve a disturbing intervention. Modern digital camcorders (without inflexible land-or ship-based cable connection) such as the GoPro camera enable undisturbed and unmanned, stationary close-up observations. Such observations, however, are also very time-limited (~3 h) and full 24 h-recordings throughout day and night, including nocturnal observations without artificial daylight illumination, are not possible. Herein we introduce the application of modern standard video surveillance technology with the main objective of providing a tool for monitoring coral reef or other sessile and mobile organisms for periods of 24 h and longer. This system includes nocturnal close-up observations with miniature infrared (IR)-sensitive cameras and separate high-power IR-LEDs. Integrating this easy-to-set up and portable remote-sensing equipment into coral reef research is expected to significantly advance our understanding of fine-scaled biotic processes on coral reefs. Rare events and long-lasting processes can easily be recorded, in situ-experiments can be monitored live on land, and nocturnal IR-observations reveal undisturbed behavior. The options and equipment choices in IR-sensitive surveillance technology are numerous and subject to a steadily increasing technical supply and quality at decreasing prices. Accompanied by short video examples, this report introduces a radio-transmission system for simultaneous recordings and real-time monitoring of multiple cameras with synchronized timestamps, and a surface-independent underwater-recording system.

No MeSH data available.


Related in: MedlinePlus

Different bite rates of butterflyfishes on four coral colonies calculated from the same video recording using either short-term intervals of two hours (morning, midday and afternoon) or the entire video sequence of eight hours.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4017077&req=5

Figure 5: Different bite rates of butterflyfishes on four coral colonies calculated from the same video recording using either short-term intervals of two hours (morning, midday and afternoon) or the entire video sequence of eight hours.

Mentions: To demonstrate the utility of the system, we used one of the recordings obtained during the in situ caging experiment to test whether a prolonged recording period provides more accurate data than typical short-time recordings of standard camcorders. The respective video lasts 8 h and shows butterflyfishes foraging on four different colonies. For this test, the overall recording time of 8 h was subdivided into three 2 h-long intervals (morning, midday and afternoon) and the bites per hour calculated from each of these intervals were compared to the values derived from the overall recording time (Figure 5). This test clearly demonstrates that due to different grazing rates in the course of a day the most accurate value is provided by the long-term monitoring method. Chi-squared tests calculated for the number of bites (standardized to the lowest observed value) between every 2 h-interval and the overall recording reveals that bite rates differed significantly between all short- and the long-term recording (morning vs. overall: χ2= 20.6, p < 0.001; midday vs. overall: χ2 = 13.4, p < 0.01; afternoon vs. overall: χ2 = 72, p < 0.001).


Coral Reef Surveillance: Infrared-Sensitive Video Surveillance Technology as a New Tool for Diurnal and Nocturnal Long-Term Field Observations.

Dirnwoeber M, Machan R, Herler J - Remote Sens (Basel) (2012)

Different bite rates of butterflyfishes on four coral colonies calculated from the same video recording using either short-term intervals of two hours (morning, midday and afternoon) or the entire video sequence of eight hours.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4017077&req=5

Figure 5: Different bite rates of butterflyfishes on four coral colonies calculated from the same video recording using either short-term intervals of two hours (morning, midday and afternoon) or the entire video sequence of eight hours.
Mentions: To demonstrate the utility of the system, we used one of the recordings obtained during the in situ caging experiment to test whether a prolonged recording period provides more accurate data than typical short-time recordings of standard camcorders. The respective video lasts 8 h and shows butterflyfishes foraging on four different colonies. For this test, the overall recording time of 8 h was subdivided into three 2 h-long intervals (morning, midday and afternoon) and the bites per hour calculated from each of these intervals were compared to the values derived from the overall recording time (Figure 5). This test clearly demonstrates that due to different grazing rates in the course of a day the most accurate value is provided by the long-term monitoring method. Chi-squared tests calculated for the number of bites (standardized to the lowest observed value) between every 2 h-interval and the overall recording reveals that bite rates differed significantly between all short- and the long-term recording (morning vs. overall: χ2= 20.6, p < 0.001; midday vs. overall: χ2 = 13.4, p < 0.01; afternoon vs. overall: χ2 = 72, p < 0.001).

Bottom Line: Integrating this easy-to-set up and portable remote-sensing equipment into coral reef research is expected to significantly advance our understanding of fine-scaled biotic processes on coral reefs.The options and equipment choices in IR-sensitive surveillance technology are numerous and subject to a steadily increasing technical supply and quality at decreasing prices.Accompanied by short video examples, this report introduces a radio-transmission system for simultaneous recordings and real-time monitoring of multiple cameras with synchronized timestamps, and a surface-independent underwater-recording system.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Integrative Zoology, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria; juergen.herler@univie.ac.at.

ABSTRACT
Direct field observations of fine-scaled biological processes and interactions of the benthic community of corals and associated reef organisms (e.g., feeding, reproduction, mutualistic or agonistic behavior, behavioral responses to changing abiotic factors) usually involve a disturbing intervention. Modern digital camcorders (without inflexible land-or ship-based cable connection) such as the GoPro camera enable undisturbed and unmanned, stationary close-up observations. Such observations, however, are also very time-limited (~3 h) and full 24 h-recordings throughout day and night, including nocturnal observations without artificial daylight illumination, are not possible. Herein we introduce the application of modern standard video surveillance technology with the main objective of providing a tool for monitoring coral reef or other sessile and mobile organisms for periods of 24 h and longer. This system includes nocturnal close-up observations with miniature infrared (IR)-sensitive cameras and separate high-power IR-LEDs. Integrating this easy-to-set up and portable remote-sensing equipment into coral reef research is expected to significantly advance our understanding of fine-scaled biotic processes on coral reefs. Rare events and long-lasting processes can easily be recorded, in situ-experiments can be monitored live on land, and nocturnal IR-observations reveal undisturbed behavior. The options and equipment choices in IR-sensitive surveillance technology are numerous and subject to a steadily increasing technical supply and quality at decreasing prices. Accompanied by short video examples, this report introduces a radio-transmission system for simultaneous recordings and real-time monitoring of multiple cameras with synchronized timestamps, and a surface-independent underwater-recording system.

No MeSH data available.


Related in: MedlinePlus