The number of overseas workers, students and their families applying for visas to come to the UK has fallen by a third over the last 12 months.
This is possible following the rule changes introduced by the Conservative government, which banned most international students and health and social care workers bringing family to the UK.
Provisional figures from the Home Office suggest the number of migrants and their family members applying for the visas fell from around 141,000 in July 2023 to 91,000 last month.
There was a particularly big drop in the numbers applying for health and care worker visas which dropped by 80% to 2,900.
The Home Office said it would "ensure we train up our homegrown workforce and address the shortage of skills".
A spokesperson for the department said that immigration brought "many benefits to the UK, but it must be controlled and delivered through a fair system".
Executive co-chairman of the National Care Association,Nadra Ahmed said the sector had started to see some staff return home or move to countries with "a less hostile environment around immigration".
Speaking to the BBC's Radio 4 Today programme, she said: "If we had a domestic workforce willing to work then we wouldn’t need these international recruits."
She added it would "take a few years" to build up a domestic workforce and warned that vacancies in the sector could rise to unsustainable levels.
The reduction in international students applying for visas could also hurt universities already facing financial pressures.
The new rules which appear to have caused the steep fall in visa applications was introduced by former Prime Minister Rishi Sunak in a bid to reduce immigration levels down from record highs.
In 2022, legal net migration soared to 764,000, but fell by 10% the following year. The Office for National Statistics says it was "too early to say if this is the start of a downward trend".