Remote sensing

Remote sensing, which includes aerial photography, photogrammetry and LiDAR surveys, is an increasing useful tool for ecologists, archaeologists, land managers and the agricultural sector. We now offer a comprehensive remote sensing data capture and data analysis service.

Recent advances in sensor technology have greatly reduced the costs of gathering high quality data and it is now possible to survey large areas of land or water at low costs using this technology.

Together, our in-house GIS and ecological survey experts, bioacousticians and our Chief UAV Engineer and Pilot have developed a comprehensive remote sensing service that includes aerial survey using conventional manned aircraft and both fixed wing and multi-copter unmanned aerial vehicles (UAVs), which are also known as drones.

Remote sensing graphical illustration

Advantages of remote sensing

With the vastly reduced cost of sensor technology, remote sensing offers many advantages over conventional survey techniques, including:

  • Greater accuracy
  • Time efficiency (large areas can be covered in a short space of time)
  • Repeatability (survey transects can be re-flown following precise flight paths)
  • Defensible data (remote-sensed data is less prone to surveyor bias)
  • Less intrusion, low disturbance (aerial surveys of birds and cetaceans avoid disturbance bias)
  • Creation of 3D models (LiDAR and photogrammetry can provide both surface and canopy data)

Read more about our service below, or contact us today to discuss how we can apply our innovative approach to your project.

Marine mammals and sea birds

We have developed an entirely new approach to gathering marine mammal and sea bird data, combining conventional boat based surveys (e.g. Marine Mammal Observer surveys and JNCC European Seabirds at Sea (ESAS) bird surveys) with innovative UAV-gathered high definition aerial photography and bioacoustic surveys of cetaceans and seabirds.

Our methodology is based upon the accepted standard for aerial survey effort[2]. Working under extended visual line of site (EVLOS), this operational method has been approved by the Civil Aviation Authority (CAA) and allows us to cover large survey areas in a single day. The ground control station is based on a survey vessel that is in constant contact with the UAV, but positioned at least a kilometre away, so as not to cause disturbance to birds or marine mammals.

We also deploy full spectrum bioacoustic recorders (either towed or deployed remotely). Bioacoustics combined with aerial surveys can provide reliable data on the density of marine mammals (e.g. Williamson et al, 2016[3]) and this combined method was found to reduce availability bias of aerial surveys, which can only detect marine fauna when they are at the surface.

  • Read more about our bird surveys here
  • Read more about our marine mammal surveys here
SM2M remote sensing equipment is launched

SM2M remote sensing equipment is launched

Advantages over existing survey techniques

Our new approach is more comprehensive than other existing survey techniques, as well as being more accurate and safer. Safety is critical, as manned aircraft flying at low altitudes, which are traditionally used for aerial surveys of sea birds, whales, dolphins, seals and other marine megafauna, have a considerable safety overhead. Eleven marine mammal surveyors have been killed while carrying out marine surveys (Hodgson et al, 2013[4]).

A 2016 publication concluded that UAVs are much more effective at monitoring seabird colonies than traditional ground-counting methods. Use of ‘drones’ achieved a very high degree of precision, was less disruptive to the seabirds and captured clearer images (Read more here).

Data processing

We have considerable experience of processing large quantities of data. Following surveys, we are able to process the data quickly and accurately to provide a comprehensive assessment of the use of the site.

We are experienced and rigorous when processing large digital data sets. We have developed highly efficient techniques that allow relevant signals such as seabirds to be extracted from background noise, dramatically reducing data processing time. In addition, all data is also manually identified by our trained biologists, who are experts in species identification from aerial images. Our process also includes peer review of at least 10% of data to ensure quality is maintained. For instance, 10% of our bird IDs are subject to validation by JNCC-approved experts.

Anja Wittich, Marine Consultant, analysing passive acoustic monitoring data

Anja Wittich, Marine Consultant, analysing passive acoustic monitoring data

LiDAR surveys

LiDAR sensor technology has made significant advances in recent years and reductions in costs have made the technology highly cost-effective. LiDAR stands for Light Detection and Ranging.

LiDAR has a particular advantage in not only providing an accurate digital terrain model (DTM), but also recording the height of the vegetation in the Digital Surface Model (DSM). The data is therefore very useful for monitoring vegetation growth such as moorland regeneration or forest height. The 3cm accuracy of our sensor means that the data is also very useful for archaeological surveys or surveying otherwise inaccessible sites such as cave systems, derelict buildings or tall structures.

Our LiDAR sensor can be hand-held or mounted on a UAV or conventional aircraft.

High-Definition Aerial Photography and Photogrammetry

Sensor technology is now advanced enough to provide high definition photographs at very low cost. Our aerial photography service provides a Ground Sampling Distance (GSD) of less than 2.5cm (at 350m flight height). High quality imaging combined with accurate GPS positioning also allows the images to be processed to create a 3D model of the surface using photogrammetry. This would be useful for creating a Digital Surface Model (DSM) (used in archaeological surveys or surveying inaccessible structures) or measuring the height at which birds fly across a specific site.

Aerial surveys

We offer aerial surveys using either conventional manned aircraft or unmanned aerial vehicles (UAVs) to carry our sensors.

Dolphin by Anja Wittich, Marine Consultant

Dolphin by Anja Wittich, Marine Consultant

Unmanned Vehicles

Our fixed wing UAV is a long range vehicle that can be sea-launched and sea-recovered It can carry a variety of payloads, including our LiDAR and a camera that gives a Ground Sampling Distance (GSD) of less than 3cm. For marine surveys (e.g. of sea birds and cetaceans), we combine UAV surveys with boat-based observation (see marine and seabird surveys page)

Our in-house Chief UAV Engineer and Pilot, Steve Howe, has designed our UAV to be highly flexible and capable of being used both on marine and terrestrial surveying missions.

Conventional aircraft

For sites where UAVs are not appropriate (e.g. large scale surveys or inaccessible locations), we also offer conventional aerial surveys using manned aircraft. For marine surveys, because of improved safety, we use a twin engine Diamond DA42 Twinstar, which can be fitted with any of our sensors.

Contact us to discuss how we can apply our innovative remote sensing surveying techniques to your project

[1] Camphuysen, K.J., Fox, A.D., Leopold, M.F. & Petersen, I.K. (2004) Towards Standardised Seabirds at Sea Census Techniques in Connection with Environmental Impact Assessments for Offshore Wind Farms in the U.K.: A Comparison of Ship and Aerial Sampling Methods for Marine Birds, and Their Applicability to Offshore Wind Farm Assessments. NIOZ Commissioned by Cowie Ltd. Thaxter, C.B. & Burton, N.H.K. (2009) High Definition Imagery for Surveying Seabirds and Marine Mammals: A Review of Recent Trials and Development of Protocols. British Trust for Ornithology Report Commissioned by Cowrie Ltd. ISBN: 978-0-9561404-5-6.
[2] As [1] above
[3] Williamson, L.D., Brookes, K.L., Scott, B.E., Graham, I.M., Bradbury, G., Hammond, P.S. and Thompson, P.M. (2016). Echolocation detections and digital video surveys provide reliable estimates of the relative density of harbour porpoises. Methods in Ecology and Evolution doi: 10.1111/2041-210X.12538. Available from: http://onlinelibrary.wiley.com/doi/10.1111/2041-210X.12538/abstract
[4] Hodgson A, Kelly N, Peel D (2013) Unmanned Aerial Vehicles (UAVs) for Surveying Marine Fauna: A Dugong Case Study. PLoS ONE 8(11)).