Quite the contrary.
''We have no issues with getting volunteers whatsoever,'' Mr Marshall said recently.
''We actually limit the numbers to make sure those who are truly interested in doing it actually get work.''
While other southern emergency volunteer organisations are struggling for numbers, that is not the case with Wanaka Search and Rescue.
Mr Marshall said the number of calls for help had dropped away recently.
''This has been the leanest year almost for ever.''
There was ''no rhyme or reason'' to the pattern of callouts.
''It's just been a good period. We know that in the next 12 months it probably won't be. That's just the nature of the beast.''
The demand for search and rescue services was one of the reasons limits were set on the number of volunteers accepted.
''There's no fun in saying you are interested in something, volunteering, and then never getting called up.''
Search and rescue operations could require anywhere between three and 20 people in the field.
Common callouts were to mountain bikers injured in awkward places. They might require just a couple of volunteers to help them walk out or someone to attach them to a helicopter strop so they could be lifted out.
Wanaka search and rescue is divided into four main groups - alpine cliff rescue, swift water rescue, sub alpine and incident management. There are also a couple of dogs used for tracking.
Many volunteers are specialists in their field.
''We live in a town full of talented outdoor people, so, something like search and rescue, certainly to date, hasn't struggled to find people who are interested in giving something back,'' Mr Marshall said.
Mr Marshall said the other aspect of having a good number of volunteers was having employers willing to let them ''disappear at the drop of a hat''.