The chilling number of deaths of vertebrate animals run over Spanish roads already has a sad balance that could amount to 55 million living beings.
The preposition “up” gives an idea of the uncertainty of calculation “Although real values could be much greater», According to the SAFE-STAP project, fauna abuses in Spain led by the Doñana Biological Station of the Higher Council for Scientific Research (CSIC)».
In the count of species that remain on the Spanish roads they are collected «amphibians, lizards and small birds as the most affected groups, ”reflect the drivers of this work.
The first in the world
«Up to 55 million They could be dying on Spanish roads», Emphasize in this study initiated by the Ministry for Ecological Transition and Demographic Challenge (Miteco).
This study is the “first in the world” that Investigate national skills through citizen science. The Doñana – CSIC Biological Station has been the scientific responsible and has been responsible since the selection of sampling methodologies to the analysis of the Data taken by volunteerincluding biased estimate. For its part, the Spanish Herpetological Association, the SECEM and SEO/BirdLife have coordinated the volunteers.
The research has been based on the data taken for a year by these people While they toured fixed itineraries, on foot, by bicycle or by carat least once a month.
Building hit on a road (Photo: Jacinto Román / CSIC)Through a mobile application
On each visit, They recorded the run -over vertebrates they found by a mobile applicationtaking photos of them in the paths made on foot and by bicycle.
Thanks to your participation, Data were collected in 304 different places from 45 of the 50 Spanish provinces between October 2020 and March 2024. “Without this collective effort, it would not have been possible to get such a amount of data,” they have highlighted from the CSIC.
The state agency explains that the information of the volunteers could not be used directly to estimate mortality, since it should be previously corrected to minimize the effect of several biases. In recent years, YH have been investigatedAn published the results through different articles.
Corzo hit in BurgosComplicated record
Thus, they point out that one of the factors to consider is that the animal run over does not always remain in the place of collision, so its registration is complicated or even impossible. You can get bounced after the collision, get trapped in the vehicle or die elsewhere due to the injuries of the outrage.
Another factor is the persistence of the body. The action of scavengers or others Factors such as road maintenance or continuous vehicle passage can cause the body to disappear from the search area. The last bias has to do with search effectiveness. Small species or asphalt -like colors are more difficult to detect.
Apart from that, the CSIC also affects that one of LAs applications used in the study has helped improve species identification through photos validated by experts.
Data reliability
And is that the field essays of the scientific team of the Doñana Biological Station showed that volunteering It was not always very precise in the quantity and quality of the data taken.
In addition, it was observed that They were registered ten times less abuses in the paths made by carespecially in the case of small animals such as amphibians and lizards
Researchers underline the “urgent” need to adopt conservation and mitigation measures to protect biodiversity and reduce fauna deaths on roadsBetween 18 and 55 million deaths on roads
Estimates revealed that, in total, Between 18 and 55 million vertebrates could be dying run over the Spanish roads. One of the most affected groups would be the amphibians.
On the same level, the lizards They also have high mortality, which could have important implications for their conservation. EITHERAfter more vulnerable species due to abuses are small birds. Among other groups studied are micromamifers, rabbits and hares and carnivores, also with important mortality rates.
Alarming situation
According to Carlos Rodríguez, research technician at the Doñana – CSIC Biological Station, these figures reflect an alarming situation about fauna mortality On Spanish roads.
In addition, they underline the “Urgent” need to adopt conservation and mitigation measures To protect biodiversity and reduce fauna deaths on roads, “the combination of fauna and fenced steps is the most effective, as long as they are well designed and executed,” Rodriguez explained.
