8. apr. 2024 Globalt, Sverige

Nature restoration stories: "Frog inventories"

  • Naturrestaurering

Why do we make frog inventories? How do we find frog habitats? And how is SCALGO Live used to protect frogs and their environments? Fredrik Engdahl from Ekologigruppen talks about how he prepares for surveying frogs and other amphibians with SCALGO Live.

Ekologigruppen is a consulting company with strong values based on ecological, social, and economic sustainability. The company operates in an interdisciplinary manner and is a driving force in knowledge and method development in green urban planning and nature conservation.

Fredrik Engdahl is an aquatic ecologist who works extensively with frog and amphibian inventories when new urban areas are developed, and amphibian habitats might be at risk.

"We use SCALGO Live to prepare the fieldwork for surveying amphibians", says Fredrik. Amphibians are frogs, toads, salamanders and similar.

"The inventory itself is always done in the spring when it is naturally wet, but we prepare the work and estimate the time required well before we start the field work."

Amphibians are protected and, therefore, we need to avoid harming them. In addition, their habitats may be protected, and, in that case, measures are needed to maintain their natural environment.

To prepare the inventory, maps of water accumulation and flow in the area are created. These maps show depressions where water naturally collects during wet seasons and flow paths that represent how water moves through the landscape.

"We're trying to find the frogs' habitats and figure out how they move around in the area", Fredrik explains.

"SCALGO Live is very valuable, because we quickly get an idea of the area and can make initial assessments of whether there are suitable conditions for amphibians. In most cases, such information is not available."

Fredrik Engdahl, Ekologigruppen

Figure 1. Depressions where water accumulates are a good indication of likely habitats for amphibians.

The soil type in the area may also be important. If it is a soil type with little infiltration, such as clay, more water can accumulate on the surface.

"Previously, we worked in traditional GIS software", continues Fredrik, "and there you had to collect and piece together data. It took a long time. SCALGO Live is very valuable, because we quickly get an idea of the area and can make initial assessments of whether there are suitable conditions for amphibians. In most cases, such information is not available.”

Figure 2. Common toad on its way to breeding grounds. The male grooms a female and takes the opportunity to hitch a ride.

"In an urban development site, we can also draw planned property boundaries into SCALGO Live and immediately see how the properties relate to the frog’s habitats and if the plan disturbs frogs.”

Fredrik Engdahl, Ekologigruppen

With information from the amphibian inventory, Frederik and his colleagues help assess whether the development plans disturb the amphibians and what measures must be taken to reduce negative impacts, protect the habitats and maintain the ecological function of the area.

"In an urban development site, we can also draw planned property boundaries into SCALGO Live and immediately see how the properties relate to the frogs' habitats and if the plan disturbs frogs," explains Fredrik.

A possible measure to maintain ecological function for amphibians is to implement a new pond. This is where SCALGO Live comes in handy again – with a detailed description of the topography and more, Frederik can quickly assess where it is worthwhile to place different measures.

"The focus of most measures is to ensure that the frogs have it as good as before and preferably even better," concludes Fredrik.

Hampus Åkerblom,
Regional Head of Market
hampus@scalgo.com
Fredrik Engdahl,
Water ecologist
fredrik.engdahl@ekologigruppen.se