Header Image MSU Link GRI Link NGI Link
Showing posts for April, 2016
Friday, April 22, 2016

Improving Created Wetland Function with Data from Unmanned Aerial Vehicles

Large-scale coastal wetland creation is typically accomplished by placing hydraulically dredged material into a confined area where it de-waters and settles to a designed elevation. The result is a flat homogeneous platform with minimal habitat variability.

Approaches to increase habitat function on newly created marsh often include the removal of barriers to tidal exchange (such as containment dikes) and the excavation of tidal channels to provide variability in habitat and increase land/water edge interface. Typically, the location and specification of these additional habitat features are part of the initial project design and do not consider post-construction site conditions which could be integrated to improve habitat function. By identifying a means to measure minor variability in the elevation of the constructed wetland platform, project managers can connect areas of lower elevation with the excavation of tidal channels. Identifying and connecting existing depressions in the newly created wetland platform can maximize habitat function and minimize the cost of installation of functional features.

At the Bayou Dupont marsh creation project in SE Louisiana, the NOAA Restoration Center partnered with the Northern Gulf Institute and Mississippi State University to collect high resolution imagery using unmanned aerial vehicles. The imagery and associated ground control points were used to create a digital surface model using structure from motion. Structure from motion (SfM) is a range imaging technique; it refers to the process of estimating three-dimensional structures from two-dimensional image sequences. This pilot project will help to evaluate the value of digital surface models created using structure from motion with data collected from unmanned aerial vehicles. Lessons learned will support advances in low-cost data acquisition and effective management of large-scale created wetland projects.

Mel Landry III
NOAA Restoration Center

Friday, April 22, 2016

Mapping Sensor Integration for EMILY Unmanned Surface Vehicles

The Emergency Integrated Lifesaving Lanyard (EMILY) Unmanned Surface Vehicle (USV) was originally designed to be deployed in rugged shallow water conditions by lifeguards as a surf rescue craft, and possesses a number of characteristics well suited to this operational environment. Our current project is focused on integrating sonar sensors on EMILY USVs, in order to produce detailed maps of shallow coastal seafloor bathymetry and imagery.

The first sensor added to the EMILYS was a single beam sonar, which uses reflected sound waves to measure the distance from the bottom of the USV to the seafloor. These observations are corrected with vehicle pitch, heading, and roll information, collected with an inertial measurement unit, to produce maps of coastal water depth. The second sensor added to the EMILYs was a side scan sonar, which uses obliquely reflected sound waves to produce an image of a swath of the seafloor beneath the USV. Automated processing and georeferencing of the sonar data will be done on a dedicated survey computer and the resulting products will be stored in a ruggedized solid-state drive.

The resulting coastal survey capable EMILY USVs will have to capacity to map coastal habitats and seafloor features with a high degree of resolution, while conducting pre-programed survey missions. This new capability has the potential to result in greater seafloor survey efficiency relative to traditional crewed vessel. Additionally, these EMILYS USVs could be rapidly deployed to location of natural disasters (e.g. , hurricane landfall) in order to survey coastal waters for morphological change and the presence of submerged debris including channel obstructions, which represent hazards to vessel navigation.

Monday, April 11, 2016

Development of a Cost-effective, Efficient Method to Control Fish-eating Bird Abundance at Aquaculture Facilities

Pelicans and other fish-eating birds can cause significant damage to a catfish farmer's way of life. In recent years, the amount of catfish ponds in the Delta has decreased by 50%. Farmers have claimed to see more fish-eating birds and that their normal scaring methods are no longer effective. The current scaring methods typically include the use of a bird chaser, who uses pyrotechnics and strategic culling with a shotgun while driving around the complex in a vehicle. Birds become accustomed to these noises when the sounds occur frequently at regular intervals and intensities. With the costs of depredation, spread of disease, and costs of harassment, catfish farmers need better and more cost-efficient ways of scaring fish-eating birds off their ponds than the commonly used tactic of human harassment.

Another scare tactic that has not yet been tested is the use of unmanned aerial vehicles (UAV). UAVs have become increasingly popular for research in the wildlife field. For the catfish farmers, this method could be highly effective at scaring pelicans and other fish-eating birds away from their facilities. Using UAVs would require less labor and with today's rapid advances in technology, it could be much cheaper than human harassment in the future. However, the efficacy of UAVs as avian scaring devices has not been assessed. This is the goal of our current research project at Mississippi State University. We want to develop a new scaring tactic for catfish farmers to use that will be effective, cost-efficient, and will keep bird habituation to a minimum.

This study is a collaborative research effort involving USDA/WS National Wildlife Research Center and Mississippi State University's Department of Wildlife, Fisheries, and Aquaculture and Geosystems Research Institute. UAV pilots, David Young and Sean Meacham, from Mississippi State's Geosystems Research Institute will remotely fly a Phantom II quadcopter around the perimeter of the ponds then focus on harassing any birds still left in the area. A Department of Wildlife, Fisheries, and Aquaculture graduate student (Ciera Rhodes) and NWRC staff are measuring the immediate percent reduction in bird abundance, which means we will be counting the number of birds that return during the first hour following harassment. In addition to the UAVs, we are also observing the catfish farm's bird chasers during their normal routines. This way, we can compare the two techniques to determine which scaring tactic is more effective for fish-eating birds. This research is funded by the U.S. Department of Agriculture, Wildlife Services' National Wildlife Research Center (NWRC). The mission of the NWRC is to apply scientific expertise to resolve human-wildlife conflicts while maintaining the quality of the environment shared with wildlife.

If you have any questions, contact Ciera Rhodes at car267@msstate.edu.