Environmental advocates called for an investigation into the pre-breeding population size of eastern grass owls, the population density of rodents and the preservation of habitats for the critically endangered bird species in the Shalun Science Park development project.Based in the Shalun (沙崙) area. Add TT as Preferred Source Environmental advocates called for an investigation into the pre-breeding population size of eastern grass owls, the population density of rodents and the preservation of.