Analysis by the Association of Directors of Children's Services (ADCS) shows that from April 2017 to March 2018, there were 65 changes in director of children services (DCS) post holders.
The record total is nearly a third more than the number in 2016/17 (44) and significantly above the average annual figure over the association's 11-year history (47).
The changes were spread across 57 local authorities, with eight councils having experienced two DCS changes over the 12-month period.
Stuart Gallimore, ADCS president, said some "churn" in DCS post holders was to be expected, but that the past year represented a "high level of turbulence".
He said: "The majority of the changes have been accounted for by DCSs moving from one local authority to another, former DCSs filling interim positions or returning to the DCS role, and a large amount of succession from assistant director level."
This "ensures that leadership positions are held by experienced and knowledgeable individuals", Gallimore added.
Other key findings from the DCS Update 2018 analysis includes:
- 27 new DCSs were appointed, the second highest number on record
- 27 interim DCSs were appointed by councils, 15 of which were filled by assistant directors
- 18 councils currently have an interim DCS in post
- 50 per cent of councils in the North West, North East, South West and West Midlands changed DCS post holder over the year
- 40 per cent of serving DCSs have been a director in another authority
The analysis also shows there has been a marked drop in so-called "twin-hat" directors - those who combine their DCS role with running adult services or other directorates.
In 2017/18, there 46 twin-hat directors, compared with 57 a year earlier and 61 in 2014/15.
In the past year, 17 authorities have uncoupled the twin-hat role, while six have combined the children and adult directorships.
"Since 2007, around two thirds of local authorities have at some point had a combined children and adult services directorate led by a twin-hat director," said Gallimore.
"There appears to be an increasing trend in local authorities to move away from combined arrangements, however, little can be inferred from this - it is up to local authorities how they design their local systems for the benefit of local communities."