Int’l study finds that larger birds are unable to adapt to changes, temperatures

Global warming leading to drop in number of nestlings among migrating birds

Global warming is leading to a decline in the number of nestlings of migrating birds and large birds, according to a new international study that includes the University of Haifa and the Shamir Research Institute in Katzrin. Conversely, the study found an increase in the number of nestlings among smaller, non-migrating birds.

“The concern is that if the downward trend in the number of baby birds unable to leave their nests continues, this will impact the ability of the large and migrating bird species to survive in the long term. These birds play an important role in maintaining the global ecosystem,” explained Dr. Motti Charter of the University of Haifa and the Golan Heights institute, which has been operating for over 30 years to advance the practical, applicable and academic research in a varied gamut of subjects.

The study has just been published in the journal PNAS under the title “The effect of climate change on avian offspring production: A global meta-analysis.” Edited by Nils Stenseth of the University of Oslo, it included a few dozen ornithologists and other experts around the world.

Numerous studies have shown that climate change has altered avian timing of breeding and its impact on birds’ reproduction and migration habits, but little is known about climate-driven changes in offspring production.

In the current study, the large team of researchers set out to examine the impact of global warming on the reproduction of birds and specifically the number of nestlings they produce. To study and identify a connection between climate changes and alterations in the number of birds, the researchers used data collected from specific species around the globe over 15 years.

“The number of researchers worldwide who have longterm monitoring data of a specific species is fairly small, making this study unique,” Charter commented. The team collected information on 201 breeding populations from 104 species of birds from every continent and a total of 745,962 nests. They included data from the breeding seasons in 1970 to 2019, including daily temperatures, the number of eggs, nestlings per pair and the number of nests for each population.

Global temperatures have risen significantly in the 20th and 21st centuries, they wroteand changes in precipitation patterns have resulted in shifts of climatic zones, altering the conditions that animals experience in their breeding grounds, their wintering grounds and during migration.