Stewardship from the Sky: Evaluating Approaches for Remote Monitoring of Conservation Properties

By Jessie Norriss on July 10, 2020

We’ve had many organizations reach out in recent months about options for remote monitoring to keep an eye on properties while protecting the health of stewardship staff and landowners. Though some organizations had already begun to incorporate remote methods into their monitoring protocols, the current circumstances are accelerating adoption. As many land trusts are adjusting to new ways of working, we wanted to offer a few ideas on what questions to consider and how to evaluate options. (Also, as a primer before getting started, feel free to check out our remote monitoring glossary!)

Remote monitoring offers many advantages to land trusts, including cost savings and efficiency gains. The ability to inspect ground conditions across a property or compare images year-over-year enables land stewards to rapidly detect changes from baseline conditions not possible with field visits alone. Of course, relationships with landowners are core to stewardship over time -- and with new challenges around in-person time with landowners, we’re hearing about how stewardship staff is adapting the way that they monitor and protect lands and connect with landowners when in-person visits aren’t feasible. With the safety of staff, volunteers, and landowners of paramount importance at this moment, remote monitoring empowers organizations to keep tabs on easements without putting anyone at risk.

According to the Land Trust Alliance’s Standards and Practices Section 11C-2, remote methods are accepted for monitoring requirements four out of every five years, making it possible for organizations to utilize these options either as stand-alone options or to complement in-person field visits. The decision of whether and how to pursue remote monitoring is generally informed by considerations such as:

  • What is the size and number of properties your organization oversees?
  • What are the ground conditions and topography on these properties?
  • How does your organization engage with landowners?
  • What are the easement terms and potential risks of violations?
  • What is the capacity of your organization, in terms of staff and budget?

Below we outline several options for remote monitoring as well as key considerations for how to select the right option or options for your organization.

Aerial

Flyovers in an airplane or helicopter are a good monitoring option, particularly if the terrain is difficult to traverse on foot. These flights can be expensive and often are used to capture data at a single point in time but can provide crisp imagery of up to 3 cm per pixel on properties for a nuanced understanding of ground conditions. Based on how the aerial flyover is conducted, land stewards may either go up in the plane with the pilot to survey the property or inspect imagery from cameras attached to the plane after the data is captured. It is worth noting that shelter-in-place orders this spring have led to some pilots being temporarily grounded and unable to conduct planned aerial flyovers. In general, aerial flyovers still require land trusts to coordinate with licensed pilots on suitable flying conditions and monitoring at the right time of year.

  • Pros: High spatial resolution, agency on when and where you capture data
  • Cons: Cost, coordination with pilot and planning around weather or clouds, images may not be geo-referenced making comparison difficult, data processing and storage

Drones

Unmanned aerial vehicles are another great way to view easement properties or conservation lands. Like aerial data collection, drones provide detailed imagery with spatial resolution ranging from 3 to 5 cm for detailed information on ground conditions. The main constraints with drones are related to limited battery life and the distance they are needed to cover. if properties span 100 acres or more, drone batteries will need to be changed often and drone operators must still navigate properties to keep an eye on the drone. But this approach certainly can still save time compared to monitoring on foot. Check out our blog on how satellites and drones can complement monitoring to learn more about this approach.

  • Pros: High spatial resolution
  • Cons: Distance covered, coordination with drone operator to visit the property, images may not be geo-referenced, data processing and storage

Satellites

Satellites provide another solution for organizations with properties that are large, spread out, or hard to access. Additionally, it enables land trusts to gather frequent information on dynamic on-the-ground conditions with a resolution of up to 0.3 meters per pixel. The benefits of satellite data, particularly when organizations have agency of the type and timing needed, can help land trusts glean new information about their properties. For example, in addition to visual imagery, satellites capture data on vegetation and water conditions on the ground, allowing land trusts to monitor any changes to ecological conditions that could come from potential violations such as timber thinning, road construction, or clearing an area for building construction. Satellites have consistent orbit patterns and frequent data collection—capturing data as often as weekly—so it is possible to easily line up and compare imagery captured at different points in time. Though some organizations use Google Earth imagery to inspect property conditions, this approach can be unreliable as the images are not always up-to-date, making it difficult for organizations to depend on this imagery for annual monitoring and reporting purposes. Acquiring commercial satellite imagery tends to be more suited to annual monitoring as it’s possible to know and control the date of capture.

  • Pros: High frequency of data capture, well-suited to monitor large or remote areas
  • Cons: Cost and licensing if working with commercial providers directly, and expertise needed to interpret and analyze data

However, satellite data can be complicated to acquire and analyze through traditional channels. First, a contract must be established with a commercial satellite provider to acquire imagery. Next, staff is needed with specialized training in GIS and remote sensing and have experience viewing, processing, and analyzing satellite data to glean insight on ground conditions. Organizations with this skill set may choose to contract directly with a commercial satellite data provider, such as Planet, Maxar, or Airbus, to purchase imagery and do interpretation in-house.

Images covering 6, 100, 400 acres at 30, 10, 3, 0.5 meter resolutions
Images covering 6, 100, 400 acres at 30, 10, 3, 0.5 meter resolutions
Overview of spatial resolution from satellites. Imagery © 2018 Planet Labs Inc., Maxar (formerly Digital Globe), European Space Agency. All rights reserved. Post-processing and analysis by Upstream Tech.

Upstream Tech developed Lens™ specifically for land trusts who are looking for a streamlined, accessible way to view and procure satellite data from multiple sources, interpret and annotate the imagery, and easily generate compliance reports. We source satellite data from over ten public and commercial satellites to set a baseline of conditions and monitor properties throughout the year. Users without any technical background can explore this data through a web-based dashboard, as shown below, to explore conditions on conservation properties and process high-resolution imagery of their conservation properties as it becomes available over the year. Additionally, we’re able to display previously-gathered drone and aerial imagery on an as-needed basis for easy comparison and exploration. Notes made on the properties can be recorded in an automatically-generated monitoring report, removing significant time and effort involved in LTA or other compliance reporting. This remote monitoring complements on-the-ground efforts by focusing on strategic field visits and providing detailed reports to reduce workload and increase the quality of information about each site.

Upstream Tech Lens™ Dashboard comparing imagery between two years Example of Upstream Tech Lens™ Dashboard comparing imagery between two years, highlighting an area with visible changes

Overall, remote technologies can save time and resources while enabling monitoring to keep pace with land protection. Want to see this in practice? You can also check out our blog posts on restoration, drones, and satellites. As organizations adapt to changing norms this monitoring season and navigate remote monitoring options for this year and beyond, we’re here to help.