Fewer than 50 athletes in the 200 strong New Zealand Olympic team are expected to march in next month's opening ceremony at the Rio Games.
Almost two-thirds of Australia's 410 athletes are set to miss the opening ceremony as they have competition starting the next day or are staying some way away from Maracana stadium.
New Zealand athletes are in the same boat, with road cyclists, equestrian, rowers, the women's rugby sevens, and the men's and women's hockey teams all competing the following day while the women's football team has matches outside of Rio.
Several New Zealand athletes are also only arriving a few days before their event and then leaving shortly afterwards because of health concerns.
The NZOC's communication manager Ashley Abbott said the number marching would be similar to previous Games and she would not know until they arrived in Rio just who was marching and who was not.
In London four years ago only one fifth, or 39 of the 184 athletes, marched in the opening ceremony while about half the 182 strong team in Beijing marched in the opening ceremony.
The Rio opening ceremony is on 6 August.
Almost two-thirds of Australian athletes are set to miss the opening ceremony for similar reasons.
The Australians have also implemented strict security rules.
No female athlete will be allowed out of the village unless accompanied by a male, and any group must travel in a minimum of three.