Aviation safety benefits endangered species
All the green spaces at Swedavia's airports are cut regularly for aviation safety reasons, which has had an unsuspected positive impact on the environment. These large, meadow-like fields have given rise to a unique variety of species and become the habitat of a number of endangered species, such as the rare purple gentian.
Maintenance of the airport runways and aircraft parking stands is linked to aviation safety. The grass is cut on a regular basis and kept short so that birds do not feel at home and risk ending up in the aircraft’s path.
To the untrained eye, these kilometres of mowed spaces do not look like a place where rare plants would thrive. But that, in fact, turns out to be the case.
“We made an inventory of the flora and fauna around Stockholm Arlanda Airport in 2010 before applying for a new environmental permit. It occurred to me that we should also look at the plants on airside in front of the fencing,” says Magnus Persson, who is an environmental advisory expert at Swedavia.
Vulnerable and endangered species
The very first survey indicated a surprising variety of species. So Swedavia decided to make an inventory of the species in the area after the security checkpoint as well. The first inventory was carried out in 2012 and the most recent one was in 2015.
“A total of 517 species were identified in the grasslands on airside. Many of them are on the European Red List of Threatened Species. That is, they’re vulnerable species under threat. One plant in particular, purple gentian, is also listed as critically endangered and is usually only found in small numbers.
“We found more than 30,000 plants here,” recalls Magnus Persson.
In addition to threatened plants, threatened species of lichen, mushrooms, butterflies, beetles and even birds were found.
“It may seem paradoxical since we cut the grass to prevent birds. But this involves the Eurasian skylark, which is a vulnerable species under threat. It thrives here and is so small that it does not constitute a threat to aviation safety,” says Magnus Persson.
The threat comes instead from birds that often hunt insects in flocks, such as jackdaws, seagulls and crows.
“If we can figure out what bird species are involved in bird collisions, we can more easily implement the right measures,” says Magnus Persson.
He has just begun work on a bird and wildlife manual for the airports that is focused on precisely these issues. External work is also under way to map out what birds frequent the airport and why they are there.
Unique meadow-like areas
But how is it that the green spaces at airports have become the habitat for such a wide variety of species? The answer is meadows and grassland.
In the past, this was a natural part of the agricultural cycle. The meadows were cut after midsummer. The nutrients were moved with the hay to the farms and reused as fertiliser for the fields. Over time, large meadows have become increasingly less common, so the airports’ enormous grasslands are nowadays unique meadow-like areas.
These grass areas are cut for safety reasons. They cannot be too high or too lush, but they are not cut unnecessarily. The seeds from this abundant habitat are spread with the grass clippings along the kilometres of runways.
“It’s an ideal situation, where aviation safety and environmental care go hand in hand,” notes Magnus Persson at Swedavia.