First came the rain, then the temperature dropped precipitously, delivering a chilling intimation of winter to keep drinkers and diners at bay. it was as if the weather in bristol had been marshalled into supporting the new restrictions on pubs and restaurants that came into effect across england on thursday night.

Its going to be carnage, said brendan murphy, who runs the bristol association of restaurants, bars and independent establishments. he warned that the fresh measures to combat covid-19 which include a mandatory 10pm closure for pubs and restaurants could result in more than a quarter of venues in the university city being forced out of business, with the loss of 6,000 jobs. many are also questioning their effectiveness at stemming the rise in coronavirus cases.

The sense of gloom is magnified across the country, with a quarter of british pubs and restaurants fearing collapse before christmas without more government support, according to a survey commissioned by pub and hospitality trade bodies the british beer & pub association, ukhospitality and the british institute of innkeeping.

Thesecurfew measures have stripped another 40 per cent off our business revenue and taken away our most productive trading hours, said lisa black, general manager at the beer emporium, a bar and pizzeria licensed to stay open until 2am in bristols city centre, where streets have been closed to traffic to let venues set out more tables for customers.

Aziz rahman, at the nearby raj restaurant, said his familys curry house had reopened only last week after six months, and was facing fresh disaster. many of its customers come late at night, after drinking first. it is going to hurt, he added.

Bar and restaurant managers in the city were nevertheless calling last orders and closing kitchens long before the new curfew came into effect. customers duly complied and outdoor terraces were emptied of all but staff.

But there were also gaggles of students, newly arrived for freshers week, who had no intention of calling it a night. they piled into express supermarkets to load up on more alcohol, some congregating in city parks.

If you socialise between 8 and 10 instead of 10 and 12 what difference is it going to make to transmission? said lacey trebilcook, a first-year law student at bristol university. this is going to make people more rebellious, said her companion, politics student carlos follmar, of the curfew.

Landlords and some scientists predicted as much when boris johnson, the prime minister, on tuesday announced fresh restrictions on the hospitality trade, after imposing a broader rule of six earlier in the month to limit people mingling.

The intended consequence is that everyone toddles off home alone, said bruce gray, who described himself as the big chief of small bar, a pub on bristols king street, and who also runs a craft brewery, the left handed giant.

The unintended consequence is that everyone piles out of the pub in groups and goes to each others houses and flats where they are no longer being regulated and there is no societal pressure to adhere to social distancing.

Some scientists agree, and are sceptical that the 10pm curfew will contain the rapid growth in virus cases. at best the curfew will be inconsequential. but it could have negative consequences with people clustering in pubs earlier and going to parties after, said michael head, senior research fellow in medicine at southampton university.

He pointed to a growing body of research showing that, like other indoor spaces, restaurants and bars have proved susceptible to super-spreading events. it would have been wiser, he thought, to close them altogether and compensate businesses for loss of income.

Paul hunter, professor of medicine at east anglia university, agreed. if you were not worrying about the economics and you were only worrying about the cases, you wouldnt mess about with a curfew. you would just close all pubs and restaurants.

The possibility of a nationwide closure if covid-19 case numbers continue to surge looms large over a sector that was hit hard by the weeks of lockdown but received some benefit from government measures such as the furlough scheme and eat out to help out. it will receive little from the latest employment support introduced on thursday by chancellor rishi sunak.

We have not laid off anyone. we have ducked. we have dived, said the left handed giants mr gray. rather than sack bar staff he had them delivering beer by cycle at one point, he said, and rather than batten down hatches, his business had invested 250,000 in a new brewery, where workers could operate without tripping over each other.

He warned that the new jobs scheme, in which the government will subsidise salaries for those who worked at least a third of their usual hours, had little relevance to the hospitality trade, where contracts tend to be temporary and margins wafer-thin.

Jake black is another bristol entrepreneur who has worked hard to adapt his business to the times. since march his downtown steak and burger joint, chomp, has been shut. he moved staff, who were initially furloughed, to a new tap bar at a gin distillery he part-owns, where he installed a burger truck. it proved an immediate success.

Weve not taken loans out and stuck money under the carpet. everyone has taken a pay cut and weve invested in creating a space that makes people comfortable, he said.the challenge is: will people be willing to sit here in the winter when its freezing?