Bird and Bat Survey, Mortality Risk Assessment, Monitoring and Risk Mitigation

DeTect provides expert support to project developers, owners and consultants for bird and bat survey, mortality risk assessment, monitoring and risk mitigation for wind energy projects worldwide. DeTect services in support of wind energy projects include:

• NEXRAD pre-screening site assessment
• Bird & Bat radar survey – terrestrial and offshore
• Bird detection radar systems
• Bat detection radar systems
• Radar data processing, analysis & reporting
• Bird & bat Mortality risk analysis
• Risk mitigation radar systems
• Permitting support
• Public meeting support
• Expert witness testimony

Bird & Bat Radar Technologies from DeTect

DeTect is the developer and manufacturer of the MERLIN Avian Radar System, the most advanced and proven system available for wind energy project avian survey, risk assessment, monitoring and real-time risk mitigation with over 40 systems operating worldwide. The MERLIN technology was originally developed for the US Air Force and NASA as a precision bird detection radar system to provide real-time information to controllers and launch managers to reduce bird-aircraft strike risk. MERLIN technology is highly automated providing unattended 24-7 collection of high quality data on bird activity at proposed windfarm sites that can be used to develop detailed pre-construction risk projections. With its optional MERLIN SCADA software, the MERLIN system can be used at operating wind farms to function as an "early warning" system providing advance detection of bird activity that presents mortality risk, automatically engaging response mitigation actions up to and including idling of turbines until the risk passes. 

For wind farm bat survey and risk assessment/mitigation, DeTect is developing the VESPER Fixed-beam Vertical Profile Radar that provides ultra high resolution scanning and is capable of differentiating birds from bats in the radar data stream based on measurement of wing-beat frequency and modulation. With calibration, the VESPER technology can additionally provide speciation of both bird and bat targets in certain instances. The VESPER system can be used a stand alone system or in conjunction with a MERLIN system.

DeTect provides full operational and technical support to wind farm owners and consultants for both the MERLIN, VESPER and NEXRAD bird and bat radar technologies that includes system deployment, operation, user training, and data processing, analysis, reporting and QA/QC. Staff specialists include highly experienced radar ornithologists, avian biologists and statisticians that includes the most experienced team of experts in remote sensing of birds and bats in the world - with specific expertise in design, construction and operation of bird/wildlife detection systems for real-time aviation safety and environmental management..

BirdMap™ NEXRAD Pre-screening Risk Assessment

BirdMap™ is a GIS-based system that uses processed radar data from the US NEXRAD weather radar network to provide current and historical avian population density and seasonality data on virtually any site in the continental US, Alaska and Hawaii, including most coastal and offshore resource areas. BirdMap additionally incorporates public and proprietary avian databases on habitat, threatened and endangered species, roost sites, hibernacula, bird and bat distribution species maps, and refuges along with relevant correlation issues such as wetlands, weather and visibility to develop preliminary evaluation of a proposed windfarm site. DeTect maintains the largest database in the world on bird and bat activity that includes over five years of bird density and migratory data for the continental United States with six minute updates- for both terrestrial and most offshore areas. DeTect’s BirdMap provides a unique resource for conducting a low cost “screening” assessment of proposed wind energy development sites to assist in site selection prior to investment in long term planning studies, radar studies and design.

MERLIN™ Avian Radar System

MERLIN Avian Radar System surveys provide the most cost-effective, scientifically sound, and conclusive method for collection of high-quality, statistically superior data on bird and bat movements at proposed wind turbine project locations - for both on-shore and off-shore wind turbine installations. The MERLIN bird and bat detection radar system, originally developed for the demanding aviation safety application, is the most advanced and proven technology available for bird and bat surveys with over 40 systems operating in the US, Canada,Europe, Africa and New Zealand. DeTect has extensive expertise and experience that the only staff with experience in conducting major multi-year, continuous avian radar studies for offshore windfarms.

Using state-of-the-art radar and computer techniques developed specifically for detecting and tracking the unique behavioral characteristics of birds and bats, MERLIN collects data continuously and automatically under a variety of conditions generating highly accurate, detailed datasets for analysis and for use in project decision-making and permitting. The MERLIN system is fully remotely viewable and controllable via LAN, satellite and WWAN datalinks and can operate 24-7 for extending periods unattended. Data is also archived to disk providing a permanent record for each project and t support detailed analysis and modeling to develop quantitative mortality risk projections.

Advantages of the MERLIN Technology

The MERLIN system is the most advanced technology for wind energy projects and offers significant benefits over conventional visual and manual radar ornithology avian survey techniques:

• Larger datasets of highly accurate data on bird & bat passage rates
• Detailed height & count data for the rotor swept zone
• Defines flight patterns across the wind resource area
• Quantitative determination of mortality risk
• Data archived for future reference
• Highly defensible, statistically-reliable data

The MERLIN™ Avian Radar System is the most powerful tool available for assessment of proposed wind energy projects and generates a detailed dataset that can be used to accurately determine the numbers of bird and bats transiting a proposed project site within the rotor swept areas under day, night and low visibility conditions. DeTect’s proprietary Data Analyzer program generates detailed datasets in both tabular and graphical formats quantifying the numbers of birds passing through the rotor swept area allowing precise calculation and determination of bird and bat mortality risk.

VESPER Fixed-beam Vertical Profile Bird & Bat Radar

DeTect is developing the VESPER Fixed-Beam Vertical Profile Radar based on relatively low cost and highly reliable components with an operational system projected for commercial availability in late 2009.  The VESPER technology is designed to provide species differentiation and identification based on measurement of wingbeat frequency of bird, bat and insect targets as they pass through the beam.  The beam width will be sufficiently wide to allow even large, slow flapping targets to reside in the beam for several seconds allowing for measurement.  This new sensor will be capable of being operated independently or in concert with a MERLIn bird radar system to provide specific data on the type of target that has been detected, (i.e. bird, bat or insect) and will allow inclusion and measurement of insect data for improved bird and bat mortality risks models and mitigation strategies for wind farms.

Current radar survey techniques eliminate insect targets in radar data to prevent overstating bird counts, however, by rejecting insect data rather than classifying it, important data are lost.  As an example, for a wind turbine site if insects occur at the highest densities below the rotor-swept height, it is likely that foraging bats would adopt a strategy that would place them below the rotor-swept area. A radar that can effectively and automatically discriminate birds, bats and insects will provide important information on bat migration relative to insect rich layers in the atmosphere. It is possible that bat mortality with respect to wind turbines is highest where these insect layers intersect with the rotor swept zone of the turbine and this technology could be definitive in defining this relationship. In addition to providing improved risk assessment data, the VESPER technology can also have operational application.  For example, it is known that the majority of bat kills occur in a narrow time period in the fall (approximately two weeks).  It is also known that a wind turbine with feathered blades kills few, if any, bats.  If the technology can establish a correlation between bat distribution and insect activity, then the turbines may need only to be feathered during periods when insects are in the rotor swept height and not for the entire risk period.  In this case the VESPER could be used as a monitoring and mitigation tool for operating the wind farm.  

MERLIN SCADA Bird & Bat Mortality Risk Mitigation Systems:

DeTect is leading development of advanced technologies for real-time detection and management of bird and bat risk at wind farms. For operating windfarms, the MERLIN SCADA functionality allows the MERLIN Avian Radar System to operate as a monitoring and risk mitigation system providing advance "early" warning (out to 4-6 miles) to the windfarm operators of approaching migratory or local birds under mortality risk conditions. MERLIN SCADA also can operate autonomously, automatically idling turbines when risk conditions are detected by the MERLIN system and restarting the turbines when the risk has abated.

The MERLIN SCADA operating software is fully compatible with most wind farm SCADA (Supervisory Control and Data Acquisition) systems. MERLIN SCADA can also be configured to mitigate raptor with compact conical scan sensors to address raptor risk providing continuous monitoring of the airspace above turbines, automatically stopping the rotors when raptor activity consistent with mortality risk is detected. The VESPER technology will similarly provide advance detection of bat mortality risk conditions allowing operators to idle turbines or, with the DeTect's SCADA communication software provide automatic turbine shut down and restart.

System Design & Configuration :

DeTect's bird and bat radar systems are available as fully- mobile, self-contained systems with on-board control cabin, power system, and include all hardware and software for bird and bat tracking, clutter suppression, and data recording. Custom configurations, including fully remote controlled offshore installations, can also be provided that incorporate additional sensors such as thermal cameras, bat detectors, insect detectors and vertical profilers. Systems are available for short-term rental, long-term lease or for sale from DeTect, both with and without DeTect operators and DeTect provides complete technical support from survey through data analysis.

MERLIN Avian Radar System services and rentals are also available through various MERLIN-certified consulting companies in the USA and Europe:

• USA - TetraTech, Inc., contact derek.hengstenberg@tetratech.com
• Europe - Bureau Waardenburg bv, contact s.dirksen@buwa.nl