Snakes keep nature in balance (20.9.2015)
Like 0 Dislike 0 Published on 19 Sep 2015
Snakes are among the most misunderstood of all creatures. Many people fear these reptiles and want to eliminate them - but snakes play a key role in balancing ecosystems.
In a compact metropolis like Hong Kong, not many of us regularly cross paths with snakes. Though the city is small in size, it boasts a high level of biodiversity - an impressive range of different species of plants and animal life - and that includes 52 species of snakes.
Since 2002, the Agriculture, Fisheries & Conservation Department has been conducting surveys of these snake species, of which 20 are venomous. Only one species is protected: the Burmese Python.
Snakes’ feeding habits act as a natural form of pest control as they are predators that feed on a variety of creatures. Small snakes feed on many harmful bugs and insects. Larger ones eat mice, rats, and other small mammals that can destroy crops or damage personal property.
Field Officer Wing Tang explained that snakes are also a source of food for larger predators, making them an important part of the natural food web.
“Snakes are the top predators in the food chain, they can control the numbers of insects, rats and even some frogs. They are also the food of prey for some raptors, such as the Serpent Eagle.”
Ms Tang joined the department in 2002. She patrols country parks and inaccessible islands regularly with another officer to record snake species including their location, gender and age.
“We need to build up a snake database because in the past, there was not much data about the species found in Hong Kong. We look under wooden blocks, in catchwaters and under boulders to find them.”
Serpent similarities
The Bamboo Snake and Greater Green Snake are the most common species found in Hong Kong. They cause some confusion as they resemble each other, but only one of them is dangerous.
The Bamboo Snake is the venomous one and can be identified by its bright green scales, triangular-shaped head and orange-yellow eyes. Its non-venomous counterpart, the Greater Green Snake, also has a glossy green back, but a rounder head.
Spotting them can be a challenge for field officers like Ms Tang. She does most of her research work at night, since most species are nocturnal. The Banded Stream Snake is a rare species that can be found in Sai Kung and Pat Sin Leng, but is spotted only a couple of times a year.
Despite their fearsome reputation, when left alone, snakes present little or no danger to people. Ms Tang says snakes usually prefer to retreat when encountered - but can become defensive if threatened. Most snakes in Hong Kong are harmless, though, and the numbers of known bites by highly venomous snakes and of death from snakebites are few.
People who are bitten should take note of the snake’s appearance and stay calm, she advised.
“The most important thing is that you must recognise the snake, because there are different kinds of anti-venom for different species, so when you are taken to hospital, the doctor will ask you what the snake looked like.”
Nurturing nature
Despite its small size, Hong Kong is home to a huge diversity of flora and fauna, including species of native plants, fish, birds, butterflies, dragonflies, amphibians and reptiles, and mammals.
It is the Agriculture, Fisheries & Conservation Department’s responsibility to enforce biodiversity conservation laws, carry out conservation action plans and organise educational programmes. One of the ways it does that is through the city’s first biodiversity education centre, Woodside in Quarry Bay, which opened three years ago.
Woodside features galleries that introduce biodiversity in a fun, hands-on way, including photo slideshows, touch-screen computers and live reptile and animal specimens.
“There are many live displays including the Greater Green Snake, Changeable Lizard, Hong Kong Newt and Chinese Barb, as well as several specimens in this centre. So you can learn more about Hong Kong’s biodiversity,” Ms Tang said.
Environmental educators
This year, the department joined forces with the Environment Bureau and more than 20 organisations - including universities and green groups - to plan Hong Kong’s First Biodiversity Festival which features more than 120 activities aimed at teaching people more about nature and how to cherish it.
Festival-goers can take part in family days, exhibitions, public lectures, seminars, workshops, nature tours, competitions and voluntary service.
The three-month event kicked off in September and the highlight will be the Biodiversity Carnival in Kowloon Park on November 15.
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