‘Ecological Traps’: Study Reveals Impact of Habitat Disturbance on Birds’ Social Structures

Jerusalem, 29 May, 2024 (TPS) -- Human activities affecting animal habitats are having an impact on social animals whose complex social structures and breeding behaviors are intricately linked to their surroundings, Israeli researchers have found.

A study led by Prof. Lee Koren of Bar-Ilan University found profound effects of habitat disturbance on the Arabian babbler, a social bird species known for its cooperative breeding. The findings, published in the peer-reviewed Ecology Letters journal, are the first to investigate the combined effects of habitat on both individual fitness and social tendencies in this species.

Arabian babblers have a cooperative breeding system, meaning not all members of the group reproduce. Rather, one dominant pair of babblers reproduces, while subordinate members of the flock assist by foraging for food, guarding the nest, and grooming or playing with the young. They live in groups that can range from a few individuals to as many as 20.

The research utilized a long-term dataset from an Arabian babbler population monitored since 1971 in the Sheizaf Nature Reserve of southern Israel. Under Koren’s supervision, doctoral student Alex Alamán conducted an in-depth analysis of how habitat changes impacted the fitness and life history traits of the babblers.

The findings revealed that groups of babblers living in modified agricultural areas exhibited different social structures compared to those in natural habitats.

Specifically, in the altered environments, babblers achieved dominant status at a younger age and left their natal groups earlier. Although the babblers living in the altered agricultural areas showed increased breeding events and more fledglings born, their survival rate was lower compared to the natural habitats.

“Modified habitats accelerate key life history events in Arabian babblers, such as acquiring dominance and leaving the natal group, which are crucial for their social organization,” Koren explained. “Our findings suggest that modified habitats may become ecological traps, attracting individuals due to increased breeding opportunities but ultimately reducing their survival rates.”

Currently, Arabian babblers are not considered endangered. But ongoing habitat disturbances and changes in land use could pose future threats to their populations, the researchers said.