Woodland Bioacoustic Monitoring Guide

Woodlands provide food and shelter for thousands of plants and animals, and support more invertebrates than any other habitat. Woodlands often have a rich soundscape of bird song, bat calls and other vocalisations. Thanks to the natural shelter of woodland limiting background noise, bioacoustic monitoring can be used effectively in woodland environments, as well as new-growth forests.

Bioacoustic Surveys

Bioacoustic monitoring involves deploying recording in the field for weeks or months to capture soundscape data, leading to the identification of species from their calls, song and other vocalisations. Multiple recording devices are used to determine the distribution and behaviour of species within a given survey site.

Many species can be effectively identified through bioacoustic monitoring. The diversity of which, along with the presence of key indicator species that can reflect wider environmental health.

Bird Monitoring

Birds species are not only some of our most vibrant and fascinating species that inhabit our woodlands, but also practical indicators to monitor biodiversity. Any changes to your land and vegetation will influence the type and abundance of birds. Many woodland management practices will affect the availability of food, habitat or shelter.

Support At Risk Species

According to the State of the UK’s Birds 2020 report, woodland bird populations have declined by 27% since 1970. Some specialist birds within the woodland bird indicator list have declined dramatically since 1970, including willows tits, which have shown the second biggest decline of any UK bird. The numbers of five other woodland indicator species are now less than a quarter of what they once were.

Barometers for Woodland health

The presence of certain bird species can tell you a lot about local habitats and the health of your woodland. They can also be effective indicator species; the change of species richness (number of species in a given area) and abundance of many bird species can reflect the wider change of the local environment and habitats that they rely on.

Universal

Birds are widespread, occurring in almost all woodland locations, making them a universal species group to monitor.

Bat Monitoring

Many bat species in the UK, such as the barbastelle and Bechstein’s bat, are closely associated with woodlands. These habitats provide a rich source of insect prey and numerous roosting sites. Ancient woodlands, in particular, can be especially important, offering a diverse structure and variety of tree species that support a high diversity and abundance of insects for feeding.

The presence of bat species can tell us a lot about local habitats and the health of our land. They can also be effective indicator species; the change of diversity and abundance of many bat species can reflect the wider change of the local environment and other species groups, such as insects that they prey on.

Insect Indicators

Many bat species are insectivores, consuming vast quantities of insects, including many pests that can damage crops and forests. By controlling insect populations, bats contribute to the health and productivity of ecosystems and agriculture.

Sensitive to Enviromental Change

Bats are sensitive to changes in their environment, making them excellent indicators species. They are particularly susceptible to changes in land use, such as deforestation and urbanisation, as well as to pollution and climate change. A decline in bat populations can often signal broader environmental problems.

Seasonal Woodland Monitoring

Bats, birds and other species exhibit a distinct seasonal behaviour that plays a crucial role in maintaining the balance of our ecosystems. Their activities, such as migration, breeding, and feeding patterns, change with the seasons, which is why each season’s soundscape has its own character and importance. We have found that surveying during a single season identifies as little as 50% of the total bird species that would be found in the land throughout the year. Due to the seasonal and migratory nature of bats and birds, it is important to plan your surveys at the appropriate time of year.

Birdsong Video

From a recent bioacoustic study of Scottish woodlands, we have produced the following video which outlines the behaviours of birds in different seasons, and listen to birdsong taken from the study. Please see the video below or click here.

Why Bioacoustic Monitoring?

Bioacoustic monitoring methods is one survey technique available for bird and bat surveys, overcoming challenges of traditional survey methods that can be expensive, time-consuming and impractical. It can provide valuable insights into the behaviour, distribution, and abundance of bird species, and help to inform conservation efforts and protect bird populations. 

  1. Non-invasive: Bioacoustic monitoring allows you to study birds without disturbing them or their habitats. This can be particularly important for sensitive or endangered species, as well as in areas where access is limited.
  2. Scalable: Bioacoustic monitoring can cover small and large areas quickly and efficiently, allowing you to study bird populations in a way that would be difficult or impossible using other methods.
  3. Cost-effective: Bioacoustic monitoring can be a cost-effective way to study bird populations, and the costs scale with the size of land based on the number of recording devices required.
  4. Long-term monitoring: Bioacoustic monitoring can be used to monitor bird diversity, distribution, and activity over long periods of time, allowing you to track changes in populations and study the effects of environmental factors on bird behaviour and distribution. 24-hour monitoring can capture nocturnal birds, as well as those active during daylight hours.
  5. Hard to detect species: Bioacoustic surveys can detect bird species that are difficult to observe using traditional visual survey techniques, such as species that are nocturnal, or found in dense vegetation.

Your Monitoring Plan

Your Bioacoustic monitoring plan should be designed around your requirements, and often relies on using multiple recording devices distributed across the survey site. There are several factors to consider when planning your surveys:

Recording Device Placement

The number of recording devices required is primarily dependent on the scale of the woodland, and the number of habitats that will provide alternative habitat to species (e.g. river, wetland, woodland edge). Even small woodlands can have species distributed unevenly, necessitating multiple recording devices active at the same time.

As a general rule, we recommend spacing recording devices at 500m separation. We have found that for small woodlands, only 73% of species richness (number of species in a given area) is captured from a single recording device, compared to a comprehensive monitoring set up with multiple recording devices distributed at 500m spacing.

If there are additional habitats (e.g. wetland, river, grassland, etc.) or areas of interest that are not covered by this placement, then additional recording devices can be placed at these locations. However, recording devices should not be placed closer than 250m from each other, to prevent “double counting” of identifications.

Survey Length

The survey length can be varied, based on the survey requirements. Due to the seasonal and migratory nature of birds, bats and other wildlife, it is recommended that surveys are taken at minimum, twice per year.

  • Shorter surveys (one month or less) provide a snapshot during a given season of the species richness and activity of species.
  • Longer surveys (1 – 3 months) provide greater insights into wildlife over a longer period, such as tracking migration and other species behabiours.
  • Continuous monitoring allows for a comprehensive year-round understanding of wildlife and the behaviour of species, allowing observation across all seasons.

Long term monitoring

Effective monitoring is crucial to baseline and measure progress against Woodland management plans and regulatory requirements for the promotion and preservation of biodiversity in woodlands.

  • Evaluate Effectiveness: Long term monitoring allows for the continuous evaluation of the effectiveness of biodiversity planning and land management. By regularly assessing the state of biodiversity, you can gauge whether implemented measures are yielding the desired results.
  • Adaptive Management: Biodiversity is influenced by numerous external and internal factors, and changes can occur unexpectedly. A monitoring plan provides the data needed to adapt and update management plans in response to these changes, ensuring it remains effective over time. Regular monitoring can help identify potential problems or unexpected consequences early, allowing for quick responses and adjustments to prevent minor issues from becoming major problems.
  • Inform Decisions: The data gathered from monitoring can provide invaluable insights to inform decision-making processes, from day-to-day operations to long-term strategic planning.
  • Demonstrate Progress and Achievements: A monitoring plan helps quantify the impacts of your biodiversity planning, and provide evidence of progress that can be used for reporting to stakeholders, securing funding, or validating compliance with regulations.

Want to learn more?

We conducted a study of bioacoustic monitoring in Scottish native woodland environments to evaluate the effectiveness of bioacoustic in woodland environments. Check out the full report here:

How can we help?

We offer bioacoustic monitoring services and consultancy expertise to bring unparalleled insights into the biodiversity of woodlands.

But we don’t just provide the technology – we also interpret the data for you. Our clear metrics and easy-to-understand biodiversity reports help you understand your woodland biodiversity. Feel free to get in touch for a quick conversation or free consultation based on your requirements.

Understand Species Diversity and Population Trends

Bioacoustic monitoring allows us to identify different species based on their unique vocalizations. This can help us understand the diversity of species in a given area and track changes in their activity and behaviour, measuring progress against your biodiversity plans.

Monitor Land Health

The soundscape of an ecosystem can provide valuable information about its overall health. A vibrant and diverse soundscape often indicates a thriving ecosystem, while changes in the soundscape can signal potential problems.

Non-invasive and Cost Effective

Bioacoustic monitoring is a non-invasive method, planned around your farming operations. Scale the monitoring to the size and needs of your land.

Continous and Long-term monitoring

Recorders are easy to use and can be used in a variety of habitats. Once installed, bioacoustic devices can record continuously for extended periods, capturing data day and night. This allows for long-term monitoring and the detection of patterns or changes that might be missed with intermittent surveys.

Pro Bird Survey

Custom bird bioacoustic monitoring plan based on land size and monitoring requirements

• Multiple Recording Devices
• Long-term monitoring period
• 24-hour Bird monitoring
• Custom reporting
• In-depth analysis and Bird activity trends

Pro Bat Survey

Custom bat bioacoustic monitoring plan based on land size and monitoring requirements

• Multiple Recording Devices
• Long-term monitoring plan
• Extensive night time bat monitoring
• Custom reporting
• In-depth analysis and Bat activity trends