Rising temperatures, sea levels, retreat and melting of glaciers… global warming has many impacts on the environment. Lotois birds are beginning to suffer the effects, and not necessarily for the better.
The three parts of the IPCC report, the last of which was released in April, alarm the population on the urgency to act in the face of global warming. The consequences on the environment are numerous. The four winds, the birds do not escape.
At the LPO Occitanie, Lot delegation, some phenomena are beginning to be observed. Even if Nathan Finderie, in charge of environmental studies, warns: these changes are linked to global warming, of course, but not only. Other factors can sometimes be taken into account, such as the disappearance of habitats (in particular with the mechanization of agriculture, the use of phytosanitary products, the disappearance of hedges, etc.).
Disrupted migratory flows
The biggest upheavals in the lives of birds due to climate change relate to the alteration of migratory flows. Most birds traditionally spend the winter in Africa and return to Europe for the spring. But the winters becoming milder here, some species no longer find it useful to migrate, a journey that is often long and perilous (it is necessary, for example, to brave the sandstorms of the Sahara).
This is the case of the hoopoe. This little bird, with its recognizable shrill song, is still in an in-between. Some individuals continue to migrate, and only return to the Lot between March and August, the usual route. But others become sedentary in the department. If the Lot winters continue to get milder, the entire hoopoe population is likely to stay in the area, and this for good.
The bet to migrate, or not, remains specific to each individual. Risks exist for both solutions: the dangers incurred during a migration can kill some birds. And conversely if the winter gets colder, it is the sedentary people who risk perishing, not being used to this kind of temperature. “This does not, for the moment, endanger the survival of the species”, optimizes Nathan Findie, since it splits in two.
Moreover, between the birds that have been sedentary for a long time and the newcomers, a competition for food could be created. Especially in winter when resources are scarce.
Finding food can become a complicated task. First, migratory birds arrive two days earlier every 10 years. With global warming, spring is advancing by seven days over the same period. “This will inevitably create a shift, observes Nathan Findie. The birds are trying to adapt, but they no longer migrate at the optimal time to nest and feed the chicks. This can lead to a sharp drop in population.”
Another danger: extreme episodes (such as drought or frost) that occur during periods that are usually temperate. “The birds will, once again, have difficulty feeding the chicks,” explains the researcher. And who says poor reproduction, says population decline and therefore the risk of the extinction of an entire species.
The arrival of new species
With warming temperatures, the department sees the arrival of new species, which until then lived in much warmer countries. This is the case of the white kite, a small raptor. These birds were mainly found in Africa, but in recent years they have moved up to Europe. They are now found in the white Quercy. They coexist, for the moment, very well with the emblematic kestrel.
Overall, generalist species, which adapt very quickly to a change in environment, will have few problems. In the Lot, this is the case for the magpie. A slightly different observation in specialist species, which can only live in a single environment. Like the ortolan bunting that is found a lot in the department. This small bird lives in areas dotted with trees, such as meadows or clearings, and nowhere else.
Read also :
Lot: the IPCC report worries, including the head of the Conservatoire d’Espaces Naturels
Help preserve wildlife
The LPO Occitanie, delegation of the Lot, is committed to the environment and in particular to different species, whether they take flight or not. For example, special attention is given to the ocellated lizard (largest lizard in Europe), which has a very important stronghold in the Lot. This species, classified “Vulnerable” on the national red list of threatened species established by the IUCN in 2015, needs to live in open environments to facilitate its movements. With global warming, this reptile moves one kilometer per generation (knowing that they live on average 5 to 6 years). It is therefore necessary to clear the rocky surroundings so that this ocellated lizard can continue to exist in the Lot.