The number of berths allowed on cruise ships, which is how most people see the islands, is strictly controlled. For instance, the vessel I was on, La Pinta, could carry 100 passengers but in its first season last year it could take only 32.
This season that has risen to 48 but only because owners Metropolitan Touring have taken two smaller boats out of operation. The number of hotel beds is also limited.
Anyone arriving in the islands has to pay a migration control fee of US$10 and a park fee of US$100, some of which goes towards the cost of running the park.
National park rules restrict public access to a limited number of beaches, paths and boardwalks. There must be a licensed national park guide for every 16 tourists. And, under a new rule aimed at curbing the influx of people looking for work, guides are required to have lived in the islands for several years.
There is also a big effort being put into reducing the amount of waste. Most containers now have to be returned. Recycling campaigns have been launched on both Santa Cruz and San Cristobal.
The Galapagos Islands Foundation, which operates the Santa Cruz recycling centre, also hires local fishing boats to take volunteers to other islands to clean up the masses of rubbish - "from Costa Rica, Panama and Colombia in the north and Peru and Chile in the south" as Veronica is quick to point out - washed ashore by the warm Panama current and the cold Humboldt current.
Veronica, the recycling co-ordinator, reckons that 60-70 per cent of the island's rubbish is now recycled.
"Not long ago it was all just dumped so we are making big improvements."
At the centre, organic waste is turned into compost; paper and cardboard are compacted and plastic is ground up so they can be shipped to processing plants on the mainland; and anything that might be re-used is sorted by hand.
Some of the recycled material is used by local women to make cute little black and white Galapagos penguins which are sold to raise money for the project.
And any glass in the collected rubbish is ground up, mixed with concrete and transformed into the red cobblestones which pave both the recycling centre and, increasingly, the picturesque streets of Puerto Ayoras.
FURTHER INFORMATION
To find out more about the Galapagos Islands Foundation see metropolitan-touring.com.