Ciudad Real (EFE).- A new study confirms that the increase in the planet’s global temperature has negatively affected the production of offspring in migratory and large birds, while small and sedentary species seem to benefit from this situation.
The study, led by Dr. Lucyna Halupa, from the University of Wroclaw (Poland), and signed by more than 100 scientists from research centers and universities around the world, including Dr. Antoni Margalida, from the Group of Research on Management of Hunting Resources and Wildlife of the Institute for Hunting Resources Research (IREC-CSIC, UCLM, JCCM) and the Pyrenean Institute of Ecology (IPE – CSIC), has just been published in the American scientific journal Proceedings of the National Academy of Sciences.
To reach this conclusion, the researchers examined reproduction data from 201 populations of 104 bird species (which corresponds to the monitoring of 745,962 clutches) from around the world between 1970 and 2019, as reported this Friday by the IREC in a note press.
The study controlled for phylogeny, species life history, migratory habits, latitude, direct human impacts, and local changes in temperature or precipitation.
Over 56% of birds trending downward in broods
The results show that more than 56% of bird populations showed a downward trend in brood production, especially large and migratory birds, while 44%, represented mostly by small and sedentary birds, showed a downward trend. positive trend.
Thus, everything seems to indicate that non-migratory and small-bodied birds could better adapt to ecological disturbances resulting from climate change, while the survival of large migratory bird populations could be seriously compromised as temperatures rise.
The reason for this differentiation is unknown at this time, but scientists believe it could be because large birds tend to produce fewer offspring overall, take longer to mature, and have more time between generations.
These are various factors that can slow down a bird species’ ability to adapt to climate change.
On the other hand, smaller birds tend to disperse heat more easily, which could help them regulate their body temperature more efficiently in the face of an increase in environmental temperature.
Climate change affects the availability of food and water
Finally, climate change may also be reducing food and water availability in some areas, and smaller birds may be better equipped to compete for limited resources.
Some of the species with the largest declines in pup production are Montagu’s Harrier and White Stork (large and migratory), Bearded Vulture (large, non-migratory), and House Martins (small, migratory).
In contrast, species such as the sparrow hawk, wryneck, flycatcher, and warbler appear to show positive offspring production trends as global mean temperature increases.
In general, the study authors attribute the changes in the production of offspring to the combined effects of global warming on the ecological and life history traits of the species.
According to the authors, the rapid decline in population size of some bird species documented in other studies around the world could be partially due to these changes in decreased productivity (fewer offspring produced).