Complex sentence: The Black-tailed Gull ("Larus crassirostris") is a medium-sized (46cm) gull, with a wingspan of 126-128 cm. The bird is resident in East Asia, including China, Japan and Korea.
Split into simpler sentences: The Black-tailed Gull ("Larus crassirostris") is a medium-sized (46cm) gull. It's wingspan measures 126-128 cm. The bird is resident in East Asia, including China, Japan and Korea.