THE DRAGONFLIES OF HONG KONG PART II
Classification of Hong Kong Dragonflies
Dragonflies belong to the order of insects known as Odonota, which are divided into two major subgroups: the Anisoptera (dragonflies) and the Zygoptera – (damselflies).
It is quite easy to distinguish between the 2 subgroups.
The majority of damselflies are smaller and more delicate,
like this one on the right.
Damselflies also have greater distance between their eyes, whereas most dragonfly’s eyes touch. Their ‘floppy flight’ further differentiates them, and at rest demoiselles keep their wings along their body, whilst dragonfly wings generally stick out sideways, like this dragonfly is showing us below.
In Hong Kong, insect diversity is very high; since the first local record was made in 1854, a total number of 118 dragonfly species, including two endemic species, have been recorded in Hong Kong. Interestingly, Hong Kong is home to the smallest dragonfly and the smallest damselfly in the world (respectively Nannophyapygmaea and Agriocnemispygmaea).
Here below, the Crimson Dropwing - Trithemis aurora - shows its wings.
Finding and Watching Dragonflies Dragonflies and damselflies occur in all types of habitats – even deep in forests or over fields – but generally they like areas with good water quality and with aquatic and bankside vegetation (e.g. water lilies, rushes, and weeds).
These open un-shaded habitats, such as artificial ponds and rivers may have many dragonflies, but often hold only common and widespread species. More interesting species are found in forests, around streams and shaded marshy areas, especially those with some sunny spots.
Around the ponds males defend their territories and look for females, who have come to lay eggs. Some species perch and wait, whilst others patrol the area for long periods. Adults also often concentrate in or at the edges of open areas, such as forest clearings, roadsides and grassy fields to feed on insects.
Dragonflies bask in the sun as much as possible when they need the heat for their wings. And when they need a little breather from the warmth, they move their bodies in such a way that it makes little or no direct contact with the sun’s rays.
Above, the Crimson Darter (Crocothemisservilia servilia). The males are red, whilst females are yellow, with both having a black stripe.
Sites for Dragonfly Watching in Hong Kong
The top five sites with the largest number of dragonfly species recordedare the Hong Kong Wetland Park, LukKeng, Sha Lo Tung, Tai Po Kau and WuKau Tang; whilst the watershed of Lam Tsuen river has at least 52 species of dragonfly, and high ecological value and biodiversity. Some other highly recommended areas are:
Lau Shui Heung Reservoirin the northeastern New Territories. It is a small reservoir, lushly surrounded by tall trees.
Aberdeen Valleyin Aberdeen Country Park. There is a well-wooded path that runs along Aberdeen Reservoir Road and Lady Clementi's Ride and then goes back to the Upper Aberdeen Reservoir. The many diverse stream habitats are ideal for all dragonfly species to thrive.
Lions Nature Education Centre. In Sai Kung the dragonfly pond at the Lions Nature Education Centre is the first Hong Kong water habitat made specifically for dragonflies. A visit to this pond will be a good start for beginner dragonfly watchers.
For ease of viewing and great diversity it is hard to beat the Hong Kong Wetland Park, and the Nature Centre and ponds in Tai Po Kau are also excellent.
Above, the Yellowfeatherlegs demoiselle
Code and Tips for Dragonfly Watching
Use binoculars for observation, preferably ones with a close range focus; take a dragonfly field guide to help with identification.
If taking pictures, for best results mount your camera on a tripod; and you can use your screen magnifier to observe them.
Do not collect dragonflies in the wild. Take field notes and/or photographs to help with identification. Don’t kill or collect specimens. Their bright colours fade soon after death.
Avoid environmental damage and pollution and do take away all your rubbish.
Wear long-sleeved clothes and trousers, and take a good mosquito repellent.
Keep still, be patient, and try and allow for enough time for your visit. To get the best photos use a tripod, and stalk them quietly. If they fly away, stay where you are, as they will eventually return to the same spot. They will always land after catching prey, and this can be the best time to observe and photograph them Patience and stillness are the keys. To capture them in flight use a high shutter speed and a high ISO setting
Dragonflies have quite a few enemies....below, a Golden Orb Weaver spider wraps one up for a meal later.
Some more pictures of Dragons....