An 18-year-old Victorian man has blamed rough surf and strong winds for a series of alleged assaults against girls and women on the Gold Coast.

Police allege the man assaulted eight girls and women as they swam between the flags yesterday afternoon at Surfers Paradise.

It is alleged the girls and women, aged between 15 and 24, were assaulted in a half-hour period.

They complained about the man to lifeguards, who called police.

The Pakistani national was charged with two counts of attempted rape, seven counts of sexual assault and four counts of common assault and appeared in the Southport Magistrates Court this morning.

The court heard the man allegedly sexually assaulted two of the females through their bikini bottoms.

His lawyer told the court that winds and big waves pushed her client into the women, who were swimming between the flags in separate groups.

But Magistrate John Costanzo said the man's explanation that heavy surf and wind conditions caused the alleged assaults seemed implausible.

"The Crown will argue that's the most unfortunate conspiracy of circumstances in history," he said.

Mr Costanzo denied the man's bail application because he was an unacceptable risk of re-offending.

"My view of the facts in this case is the Crown case appears to be quite strong in the allegation of eight separate, brazen and repeated sexual assaults and attempted rape," he said.

"It's an indication of a person having great difficulty controlling their sexual instincts."

Surf was 'nothing startling', police say

Outside court, detective Acting Inspector Greg Aubort said the alleged victims were asked if the surf conditions were rough and if the alleged assaults were accidental.

"We have individual reports very firm in saying these were deliberate acts," Mr Aubort said.

"If you look at the surf from yesterday, it was two to three feet, it was nothing startling in that sense."

He said other girls and women may have suffered similar experiences.

"We are encouraging any person who may have been the victim of any assault or similar to this to come forward.

"It's a terrible act to attempt to commit, particularly when you look at the age of these ladies."

The man is due back in court next month.

ABC/AAP