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        Discussion Area 討論區 >> Conservation 自然保育 >>  The Mangroves Are Dying!
        
(Message started by: KK Hui on May 26^th, 2004, 9:31am)

Title: The Mangroves Are Dying!
Post by KK Hui on May 26^th, 2004, 9:31am

I visited the WWF boardwalk hides last week and to my horror the mangroves trees on both side of the wooden path as you approach the hides were turning yellow and wilting fast. The situation seems to have worsened and spreaded affecting a wide area as I noted on another visit to the boardwalk hides yesterday. It looks like that there is a disease of some sort spreading amongst these mangroves.

Help!!!! :'( :'( :'(

KK Hui ARPS
www.geocities.com/kkhui_001

Title: Re: The Mangroves Are Dying!
Post by Forrest FONG on May 26^th, 2004, 10:55pm

Below are the photos of the dying mangroves taken this morning.
http://www.hkbws.org.hk/fileServer/PhotoG/forrest/bwmangrove01.jpg
http://www.hkbws.org.hk/fileServer/PhotoG/forrest/bwmangrove02.jpg
http://www.hkbws.org.hk/fileServer/PhotoG/forrest/bwmangrove03.jpg
http://www.hkbws.org.hk/fileServer/PhotoG/forrest/bwmangrove04.jpg
Mai Po Boardwalk 米埔浮橋
26/5/2004

It was noted that only one species is being suffered from such illness.

Forrest :'( :'( :'(

Title: Re: The Mangroves Are Dying!
Post by KK Hui on May 27^th, 2004, 10:13am

Dr Lew Young kindly gave an explanation and I quote:

"Actually, the particular mangrove trees (Avicennia marina) is not dying but for the past 10 years at least, a small caterpillar of the moth Nephoterix synaractis which has spent the winter in the tips of the twigs of the branches of the mangroves, emerges and start eating up the leaves and flower buds of the trees. After the caterpillars have all changed into moths, usually takes about 3-months, then the leaves of the Avicennia will grow back again. There is a small notice board alongside the fixed boardwalk before you reach the floating hide telling the story about this.

The caterpillar only affects one of the seven species of mangroves we have at Mai Po, but the caterpillar seems to be spreading to other mangrove forests in Hong Kong (e.g. Tolo Harbour and Sai Kung)

In the past, scientists from Hong Kong University have tried a small scale exepriment to spray the caterpillar with insecticide and this managed to allow the Avicennia to keep its leaves and flowers. However, there is a very large area of Avicennia in Deep Bay and if you were to spray all the Avicennia, you would need to do it by aeroplane and spraying that amount of insecticide over Deep Bay would have other impacts....!

We are monitoring the situation but there seems to be little we can do at the moment."

It really brings a big relief to my worry and now we can look forward to seeing their, the Avicennia marina, recovery in due course ... ;D ::) ;D

KK Hui ARPS
www.geocities.com/kkhui_001