[Animals] Climate change upsets the clock of animals and plants

[#Wittels-]

Since 1980 the natural calendar has been moving forward

A bird feeding its young. fake images

 

The United Nations Environment Program Frontiers report identifies phenological changes as one of the issues that highlights the urgent need to address the triple planetary crisis of climate change, pollution and biodiversity loss.

 

Phenological changes occur when species vary the timing of life cycle stages in response to the emission of environmental conditions. The concern is that the species that interact in an ecosystem do not always adjust to these rhythms. Furthermore, these phenological modifications are disrupted by climate change, pushing plants and animals out of sync with their natural rhythms and leading to imbalances.

"The phenological rhythms of the different living beings have been synchronizing for centuries, but now, and due to climate change, we see how that synchrony has been broken and how imbalances are taking place", confirms Fernando Valladares, CSIC scientist and associate professor from the King Juan Carlos University. “Since 1980 the natural calendar has been moving forward. The beginnings of spring are coming earlier and getting warmer,” adds Juan José Sanz, scientific researcher at the National Museum of Natural Sciences, and highlights that March, a key month for many insects –such as butterflies–, plants and birds, it is getting hotter, which, without a doubt, has consequences for their survival.

 

Visible patterns of that desynchronization can be seen, for example, in the anticipation of almond blossoms. "In the heat, they bloom earlier, but then frosts occur that end up freezing their flowers and interrupting their natural cycle, which in turn upsets the insects," explains Valladares. But "if there is a species that is particularly vulnerable to phenological changes, that is the migrant species," says Sanz.

In any case, the experts clarify that the effects of phenological changes at a structural and long-term level are not seen from one day to the next. “They are very gradual. We can see how certain species suffer individually. For example, many birds breed earlier and then have difficulty feeding their chicks, either because, in the face of frost, they remain frozen or because there are still not enough insects to feed them”, indicates the researcher from the Museum of Natural Sciences.

 

To analyze the long-term impact, the work of phenology networks is essential. In Spain, that of the Aemet is the longest, dating back to the forties. The SEO/BirdLife association and its volunteers have been nurtured from it. But many projects arise and end after a while due to lack of resources, as has happened with the program of the Spanish Network of Biosphere Reserves, says Blas Molina, SEO/BirdLife ornithologist and coordinator of the Aves y Climate, who advocates unifying forces.

 

Molina states that phenological changes are not the only ones responsible for the decline of species and highlights human activity. "With industrialized crops, the vegetation that is considered weed is eliminated and there is a decrease in insects, which means less food for the birds" Similarly, he warns about wind farms, which increases the mortality of birds, or on the large extensions of solar panels, which eliminate cultivation areas and which pose barriers to animal habitat. "The ecosystems do not know, and the human borders that the different species meet are a labyrinth for them," emphasizes Valladares, although he considers that the great labyrinth of Spain is the laws and transferred powers, which are as worrying as climate change, since that make the actions on the ground very slow.

Actions led by the Ministry for the Ecological Transition and the Demographic Challenge. On the one hand, and by European regulations, a section is included in the management plans of the Natura 2000 Network protected areas on their adaptation to climate change. This includes a list of especially vulnerable species and habitats and a connectivity plan with other protected areas. On the other hand, Spain has committed to actively protect and manage 30% of its land and sea surface by 2030.

 

Regarding the reduction of threats, the Miteco has promised to fight against invasive alien species, although Molina denounces that "adequate measures are not being taken and that the Administration is going to have to invest money to control them", and assures that are already causing significant damage to cereals and fruits, even to trees in parks.

 

THE RESPONSES OF THE SPECIES

 

Moving. Faced with climate change, the first response of species is to move from one place to another. "For example, butterflies rise in altitude, plants invade northern Europe or when holm oaks occupy beech areas in the north of the Peninsula," illustrates Juan José Sanz, scientific researcher at the National Museum of Natural Sciences.

Adaptation. Species try to adapt to the new situation. “Animals and plants use environmental clues: temperature, rainfall…, and they synchronize based on these clues; but if, for example, spring is earlier and the birds advance their migration and reproduction dates, or if it rains a lot and the insects cannot pollinate the fruits, there are desynchronizations and a cascade of reactions," says Sanz.

 

Microevolutionary processes. The museum researcher explains that when the two previous answers are not possible, evolutionary changes take place in some species, modifying their morphological characteristics in order to endure and survive.

extinction. Although it is a response that does not occur so quickly, if the different species try to adapt and do not succeed, they tend to become extinct. Sanz exemplifies it in the subalpine species that inhabited Montseny (Barcelona) in the middle of the last century and that no longer live there.

 

Link: https://cincodias.elpais.com/cincodias/2022/06/05/companias/1654459263_890286.html