the course of human settlement, the object of intense use, resulting in a general degradation of the spaces into nothing more than shrubbery. The bush and shrublands, which characterize the remainder of the spaces (74% of the park), are dominated by dwarf (Ulex minor) and European (Ulex europaeus) gorse and heather (Erica umbellata and Calluna vulgaris), with a mixtures of common juniper (Juniperus communis), southern heather (Erica australis) in the upper altitudes, while lower altitude bush includes cross-leaved heather (Erica tetralix), dwarf gorse (Ulex minor), Dorset heath (Erica ciliaris), common sundew (Drosera rotundifolia), pale butterwort (Pinguicula lusitanica), marsh violet (Viola palustris) and purple moor grass (Molinia caerulea). Riparian and marshlands along the river courses are also sites of rare species of chain ferns (Woodwardia radicans), willow (Salix repens), downy birch (Betula pubescens), deciduous shrubs (Spiraea hypericifolia), Portuguese enchanter's nightshade (Circaea lusitanica) and angelica herbs (Angelica laevis). There are 627 flora species identified by Serra and Carvalho (1989) as under pressure and considered endangered, which included two medicinal plants: tutsan (Hypericum androsaemum) and sundew (Drosera rotundifolia). Based on the protection list of botanical species, and UICN categories: 18 are considered in risk of extinction, 17 are vulnerable and one is rare. They also identified two species as extinct within the park boundaries: a geranium (Geranium lanuginosum) and fragrant orchid (Gymnadenia conopsea). There are three endemic species. Those factors that have been identified that threaten these habitats include: natural and manmade fires, use of forest for fuel wood and agricultural use of habitats. Fauna Many of the studies conducted on the species that inhabitant the park have been concentrated in the area of Matas de Albergaria/Palheiros, traditionally identified as the "heart" of the park. Work by the Faculty of Sciences at the University of Porto and University of Minho have concentrated on a few mammals (Pyrenean desman, European otter, roe deer, and wild boar), reptiles and fish. These studies looked into the numbers of species and factors influencing their habitats. Approximately 235 vertebrate species were identified within the boundaries of the park, of which 200 are threatened or under protection. These include three species of bat under pressure (of the eight that exist): greater horseshoe bat (Rhinolophus ferrumequinum), lesser horseshoe bat (Rhinolophus hipposideros) and Mediterranean horseshoe bat (Rhinoloplus euryale). Other species of particular importance: the Iberian shrew (Sorex granarius), the European pine marten (Martes martes), the European wildcat (Felis silvestris), the gold-striped