States police said that tarpaulin covers were tied to trees with chairs and tables underneath in a wooded area at the top of the sand dunes.
And the warning added that a ‘group of youths’ were spotted running away from the area.
In a social-media post, the police said: ‘Litter, drug paraphernalia and fire damage to the nearby habitat was discovered and a group of youths were seen running away from the area. We’re also aware of other incidents in the St Brelade and Les Quennevais area of damage and anti-social behaviour and we believe the same people are responsible.
‘If anyone has seen anything connected to any of these incidents or has any information they’d like to pass on to us, please get in touch.’
The post was accompanied by the hashtag #DoYouKnowWhereYourKids Are.
Officers from both the States police and the St Brelade’s honorary force have increased their patrols around Les Quennevais after the manager of the Communicare Pre-School pleaded for help because young people were repeatedly breaking into the school and damaging play equipment as well as leaving cigarette butts and other rubbish behind.
St Brelade Centenier Amanda Wright admitted that several of these camps were found over the summer months and that it was a persistent problem for the parish.
‘We hope that the perpetrators see the error of their ways and go back and clear up,’ she said. ‘This is not a one-off. It happens periodically. I suspect it is young people who have made camps, had fun and didn’t clear up after themselves.’
She added that she did not necessarily believe the dens were linked to the problems at the Communicare centre, as there had not been ‘any signs of destructive behaviour’ at the makeshift campsites.
‘This is more messy than destructive,’ she said. ‘We rely on parents to instil a sense of responsibility into their children.
‘It may be that they are kids who have set up a camp and had a bit of fun as we all did and that is fine if they take everything away with them. It is the fact there is rubbish that is the anti-social bit.’
She admitted that while it was difficult to stop these camps from appearing, the ‘honoraries are very aware of it and are keeping an eye on it’, while landowners would be responsible for clearing up the litter.
The site of the den and litter falls within the Les Blanches Banques site of special interest, one of the ten largest single dune systems in the British Isles. It is also the fourth richest in flowering plants.
