Chicks of Barn Swallow

Chicks of Barn Swallow had been seen waiting and seeking for food in their nest desperately. This is a fantastic scene to see!

Aristolochia thwaitesii

Genus Aristolochia L. (Aristolochiaceae)
Aristolochia is widely know as Birthworts which refers to the shape of the flowers as it resembles a birth canal. It contains about 400 species which is mainly distributed in tropical , subtropical and temperate regions of the Old World and also Australia. There are 45 species in China including 5 in Hong Kong. Other genera in Aristolochiaceae could be found in China include Asarum (細辛屬), Saruma (馬蹄香屬) and Thottea (綫果兜鈴屬).

Flowers of Aristolochia are protogynous, where the pistil gets mature before anthers. Pollinators carrying pollens are attracted by the flowers and enter the flowers. They are then trapped by the flowers as the retroactive hairs in the throat of the flowers help preventing the pollinators from escaping. After that, the flowers wither and the anthers dehisce. Pollens are then released onto the trapped pollinators. They are released afterward and visit other flowers to carry pollination again.

Breeding Swallows in Hong Kong

Barn Swallow (Hirundo rustica) is an abundant passage migrant in Hong Kong especially in Spring while some are summer visitors which breed in Hong Kong. It nests in a variety of places which has a widespread breeding distribution in Hong Kong. Nesting birds are thought bringing fortune and they are used to be protected by local people in Hong Kong.

Red-rumped Swallow (Hirundo daurica) is used to be an uncommon passage migrants and also winter visitors in Hong Kong. It is also found to be a breeding species in Hong Kong recently which nests in northern New Terrestories. The architecture of its nest is different from that of Barn Swallow which could be easily identified.