During the past few days university bosses have seen how unpopular their proposals to cut 115 jobs are.

More than 100 members of staff and students marched on campus to express their anger at the plans, and unions have threatened strike action if the cuts go ahead.

Bosses say they need to save £5 million in 2010-11 and believe that making difficult decisions now will help the university to grow in the future.

Courses earmarked for staff cuts include life sciences, informatics and engineering and design.

The English, history, art history and philosophy schools will also be affected.

About half the jobs are expected to go in support services, such as porters and student advisers.

The university’s deputy vicechancellor Professor Paul Layzell said: “We haven’t gone into this lightly.

We have thought long and hard about the areas put forward for possible redundancies.

“These decisions have been partly based on student demand.

For example, my own area of computer science has seen a significant reduction nationally in the number of people who want to study it.

“There has also been a change in areas of funding because projects such as computing are not attracting the same funding as issues such as climate change and security.

“With the courses highlighted, we generally now have too many staff on them.

“But we have seen growth in other subjects such as business and management, media, film and music, and global studies, which incorporates geography and anthropology.

“We are responding to a change in patterns in demand.”

Prof Layzell denied claims from the university’s student union that students’ education would be affected by the cuts.

He said: “We are not making cuts so large they would seriously deteriorate staff and student ratios.

There is only so far you can go before it has an impact and that is where we have drawn the line.”

The University of Sussex is expecting to make a loss this year of about £3 million on a turnover of £160 million.

Bosses believe a combination of reducing costs and then growing the university will help it regain financial stability.

Prof Layzell said: “It is important we find ways to bring us back into a small surplus.

“About 40% of our income comes from public funds.

“However, the level of grant we are getting today is about the same as it was two years ago.

Yet during that time there has been an increase in utility bills, pay for staff and the general cost of things.

That is partly how we have arrived in this position.

“In the next two to three years we also expect around a 10% cut in funding, as every part of the public sector is under scrutiny.

“We are trying to get to a position where we are economically and financially sustainable.

“What we are trying to do now is grow the income.

These proposals would be enough to get us to a place of financial sustainability and then it gives us a chance to grow in other areas.

“One cannot rule out more cuts if growth cannot be achieved but we are pretty confident it can be done.

“Universities are independent organisations and there is nobody to bail us out.

“We can’t put off the inevitable, we have to take the bull by the horns, tackle this problem and try to tackle it so we don’t have to come back here.”

The university is hoping to attract more international students.

Universities are limited in the number of British students they can admit but are allowed to teach as many foreign students as they want.

International students are a good source of income.

They have to pay 100% of the cost of their education so the university is not dependent on Government grants to fund their courses.

Prof Layzell said: “One of the ways we are trying to grow our way out of this situation is by attracting more international students.

“We have almost 50% more now than two years ago.

“We live in a global world and this university is committed to understanding many of the problems we are faced with today, such as climate change and security.

“We are not changing the academic shape of the university, we are not closing schools.

We are committed to having a full range of courses across the university.”

Prof Layzell also defended the salaries paid to some of the university’s top staff.

Its vicechancellor is paid £227,000 and the wage bill for the 20 top-paid staff exceeds £2.6 million.

He said the high salaries were needed to attract the best candidates to the jobs, many of whom brought significant amounts of research funding with them.

Prof Layzell added that the vice-chancellor and senior executive team had voluntarily agreed not to take a pay rise this year.

He said: “We have tried carefully to consult with staff and explain what the situation is, why we are having to do this and how they can contribute to the consultation.

“It is a difficult message to get out there because people just hear ‘cuts, cuts, cuts’.

But there is lots of growth going on as well.

This is about shifting the resources of the university so we can attract more students and more income, which is good for everybody.

“We are optimistic at Sussex that we have a bright future and lots of opportunities to grow.”