Juvenile Carcinoscorpius rotundicauda at Yi O, Lantau on 10 April 2013

Subject: Juvenile Mangrove horseshoe crabs (Carcinoscorpius rotundicauda) foraging at the inter-tidal mudflat at Yi O, Lantau, Hong Kong on 10 April 2013

Time: 1400 – 1600 hours (2 – 4 pm)

Date: 10 April 2013

Location: Inter-tidal mudflat fringed by mangroves, Yi O, Lantau, Hong Kong.

Stream fringed by mangroves. 

Inter-tidal mudflat in front of mangroves stands.

Juvenile Carcinoscorpius rotundicauda (Top picture foraging) .

Juvenile Carcinoscorpius rotundicauda (Top picture foraging).

Juvenile Carcinoscorpius rotundicauda (Top picture foraging).

Juvenile Carcinoscorpius rotundicauda (Top picture foraging).

Carcinoscorpius rotundicauda. Tung Chung, Hong Kong on 3 July 2012.

The following photographs are of one foraging juvenile and two mating pairs of  Carcinoscorpius rotundicauda (Mangrove horseshoe crab) photographed in a stream at Tung Chung, Lantau, Hong Kong on 3 July 2012:

Carcinoscorpius rotundicauda. Tung Chung, Hong Kong on 23 September 2010.

The following photographs are of dead Carcinoscorpius rotundicauda (Mangrove horseshoe crab) found alongside a stream which runs across the mudflat at Tung Chung, Lantau, Hong Kong on 23 September 2010.

The horseshoe crabs hanging in the mangrove bush are a male and female, possibly a mating pair which were swimming up the stream to spawn in the mangroves that line the stream. The animal lying on its back is a dead female C.  rotundicauda.

Streams are critical to the ecology of C. rotundicauda, because they use stream courses to navigate across beaches to reach the mangrove stands where they spawn. C. rotundicauda has also been observed to spawn in the lower reaches of streams in Hong Kong.

Mangrove stand at Tai Ho Wan SSSI cut down.

The Tai Ho Stream, Lantau, Hong Kong was designated a Site of Special Scientific Interest (SSSI 63) in 1999.  Unfortunately the protections offered by the SSSI designation in Hong Kong are limited, as the following photographs (taken on 7 June 2012) of one of the mangrove stands in the area shows: