Using a new mathematical model, a 2015 study suggested the population of 270,000 birds on Santa Cruz may become extinct in 50 years. The "Philornis" flies lay eggs in the nest including in the nestlings nostrils. The larvae feed on living tissue and in worst cases can perforate the bill. Possible solutions include the introduction of parasitic wasps which would lay eggs on the larva, or cotton wool treated with a pesticide which the adult birds would use when constructing the nest.