In the UK, the Field Cricket has disappeared from most of its historic range, due to agricultural changes resulting in a loss of shifting systems, lack of disturbance by livestock and increased rates of vegetation succession. By the 1980s it was confined to one site in West Sussex with less than 100 individuals and was expected to go extinct.
Since that time, there has been a concerted effort by several groups and individuals to shore up existing populations and to create new ones by introducing individuals to suitable sites.
I spent several hours at Farnham Heath in Surrey trying to catch adult crickets. This involved first of all finding the burrows (which are subtly different from Minotaur Beetleesons) with their semicircle singing arena at the entrance. Then a piece of grass is used to entice them out. This is the tickling bit. Once out due to their curiosity they can be placed in a bag and then moved. Males are usually easier than females to find but we quickly managed a few of each sex.
The crickets where then taken to another bit of the reserve where they'd be unable to colonise naturally (they are flightless and there are roads bissecting the habitat). On arrival we found some suitable place and let them go to reorientate themselves and to find a place to burrow. Hopefully next year will find that they have successfully established and are breeding