The headwaters of the filthy rivers running through Yuen Long are situated in Tai Lam Country Park.
This upland area was stripped of vegetation during the Japanese occupation in WWII.
Like all the Country Parks in Hong Kong, Tai Lam is mostly steep upland with isolated pockets of long abandoned paddy. The 'country parks' were designated as a device to exclude farming and other polluting activities from water gathering grounds.
Tai Lam park has some lush verdent areas
Other areas are described as 'badlands' - effectively bare earth
The combination of stripped vegetation and erosion during overland flow reduces the reservoir's capacity via sedimentation. This photo shows the reservoir during desilting operations - the volume of silt is surprising.
Indigo Dropwing (Trithemis festiva)
Pied Percher (Neurothemis tullia tullia)
Asian Pintail (Acisoma panorpoides panorpoides)
Marsh Skimmer (Orthetrum luzonicum)
Russet Percher (Neurothemis fulvia)
Common Red Skimmer (Orthetrum pruinosum neglectum)
This group of Paris Peacocks were drinking from a puddle. One butterfly book recommends urinating on the ground to attract butterflies - that is not a puddle of the author's urine, you have my word!
An unidentified Blue Lycaenidae