- Red squirrel (_Sciurus vulgaris_): The red squirrel is a native species of the UK and is considered endangered in Wales due to habitat loss, competition from non-native grey squirrels, and disease.
- Hedgehog (_Erinaceus europaeus_): Hedgehogs have experienced population declines in Wales and the UK due to various factors such as habitat loss, road casualties, and changes in agricultural practices.
- Water vole (_Arvicola amphibius_): Water voles are semi-aquatic rodents found in wetlands and riverbanks. They are facing threats from habitat degradation and predation by invasive species such as mink.
- Atlantic salmon (_Salmo salar_): Atlantic salmon is an iconic fish species in Wales, but populations have declined due to overfishing, habitat degradation, pollution, and barriers to migration.
- Marsh fritillary butterfly (_Euphydryas aurinia_): The marsh fritillary is a butterfly species that depends on specific wetland habitats. It has suffered from habitat loss and fragmentation due to changes in land use.
- Pearl-bordered fritillary butterfly (_Boloria euphrosyne_): Another threatened butterfly species, the pearl-bordered fritillary relies on damp grasslands and heathlands. Habitat destruction and grazing pressure are contributing to its decline.
- Willow tit (_Poecile montanus_): The willow tit is a small bird species found in damp woodlands. It faces challenges due to habitat loss and competition with other bird species.
- Common lizard (_Zootoca vivipara_): The common lizard is a protected reptile in Wales and the UK. It is affected by habitat loss, fragmentation, and predation from invasive species.
- Otter (_Lutra lutra_): Otters are semi-aquatic mammals found in rivers and coasts. They are vulnerable to pollution, habitat loss, and conflicts with human activities.
- Peregrine falcon (_Falco peregrinus_): While the peregrine falcon has experienced a remarkable recovery from past declines, it is still considered a vulnerable species due to ongoing threats such as illegal persecution, habitat degradation, and disturbance.
It's important to note that conservation efforts are underway to protect these endangered species and their habitats in Wales. Various initiatives focus on habitat restoration, predator control, public awareness, and legal protections to help conserve the biodiversity of the region.