Maoyu is part of Wangan Township in Penghu. It is a desert island formed by the Large Maoyu, Small Maoyu and other rocks located 16km southwest of Wanganyu. When viewed from afar, they look like two cats crouching on the sea. This is how they were named in Chinese. The highest elevation of these islands and rocks is about 70-79.
The land area of the Maoyus is about 10 hectares. They are steep island with cliffs on all four sides. The Large Maoyu is a huge dike erected on the land surface and steeper than the Small Maoyu. The latter sits east of the former. Both islands are parted by a 10m-long groove that can be seen when the tide falls. There is a wave-cut platform on one side and reefs spreading all around. The current is rapid and ships are difficult to approach.
Basalt is the main rock type on the surface layer in the area, and most part of the cylindrical texture is curved. Breccia is the main rock type in the sublayer forming a special and magnificent igneous landform. In addition, the Maoyu was announced in 1991 and amended in 1997 as the “Penghu Maoyu Seabirds Protection Area”. So far, about 45 to 55 species in over 20 families of birds have been recorded on the island.
After becoming a seabird protection area, many birds inhabit there. The brown noddy (Anous stolidus) and the bridled tern (Sterna anaethetus) are the two dominant species, commanding at 90% of the total. During bird-mating season from March to September every year, flocks of seabirds will proliferate and forage on the island, with a population over ten thousand. The view is spectacular.
As a “seabird protection area”, Maoyu is restricted to visitors. However, they can still tour around the island to appreciate the view. More important, seabird harassments and damage of the local ecosystems are strictly prohibited. Visitors who wish to land on the island must apply for permission in advance.