Rise in Gypsy and traveller caravans and sites
The number of Gypsy and traveller caravans in 21 of Wales' 22 local authorities has increased by 19%, with the number of sites also on the rise.
Figures from the Welsh government showed there were six more sites, both authorised and unauthorised, in the year to July 2013.
At authorised sites, the number of caravans increased by 97, up 14% on the previous year.
A new housing bill could require local councils to provide sites.
The Housing (Wales) Bill currently going through the assembly would place a duty on local authorities to provide sites for Gypsies and travellers where a need is identified.
Counts of this kind are carried out twice a year on a voluntary basis by councils. Powys was the only council not to respond to the latest one.
The count recorded a total of 928 caravans.
The surveys found the increase of caravans at authorised sites was largely down to more use of local authority sites in Cardiff, Pembrokeshire, Flintshire and Merthyr Tydfil.
However it noted that the total number of pitches had dropped by 21.
Of the unauthorised sites, there were 38 caravans on land owned by Gypsies and Travellers, accounting for 4% of all caravans and a further 166 on others.
The total number of caravans pitched on unauthorised sites rose by 39% from the previous year.
Joseph Jones, a Gypsy Council spokesman on planning issues and site provision, told BBC Wales the increase in caravans was likely to reflect the higher number of children born to Gypsy and Traveller families.
He said: "As they grow up they need more places to live. The sites haven't kept pace with the increase in the population. If you have a pitch on a site, you are often restricted in the number of caravans you can have on it.
"There are reasons why sites need to be regulated, for health and safety reasons, so sites will naturally be limited."
A number of councils are in the process of trying to identify locations for Gypsy and traveller sites.
In October, Swansea councillors rejected recommended options in Cockett or Llansamlet and voted to start again.
In Newport, which has no official sites, 14,000 people objected to three planned sites in Ringland and Duffryn in December.
The final decision is to be made by the Welsh government.