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        Discussion Area 討論區 >> Birding Reports & Tips 觀鳥報告及心得 >>  Terrestrial fish at Mai Po　米埔有魚陸上爬
        
(Message started by: johnallcock on May 29^th, 2006, 2:38pm)

Title: Terrestrial fish at Mai Po　米埔有魚陸上爬
Post by johnallcock on May 29^th, 2006, 2:38pm

A slight deviation from birds maybe, but I found the following observations interesting.

I visited Mai Po yesterday (28th May) after the heavy rain and noticed a number of fish on the road by the border fence.  My initial assumption was that an egret had dropped its food, but the number of fish and their behaviour made it apparent that they were deliberately on land. Obviously, we are all familiar with mudskippers but these were different and were clearly not fully adapted to life on land.

All fish were of the same species (I think they were young snakehead) and roughly the same size (about 10cm) They were heading up the track by the scrape, then almost all turned right to head north along the border fence road.  Thye were pulling themselves along by rolling to one side, opening their gill-slit and flapping their body, so that the gill slit caught on the ground, allowing the fish to drag itself along.  It looked rather painful (rather like pulling yourself along using just you chin!), but each fish was actually making fairly rapid progress, even managing to climb a steep slope up to the road.

I assume they were attempting to disperse and find a new wetland, but I was wondering if anyone else had any details of this phenomenon.  The main points that intrigued me were:
How far do the fish disperse in this way?
Why did all fish seem to be heading in the same direction, from the same area (I saw none elsewhere on the reserve)?
Why did they not simply move to the nearest area of water rather than climbing the hill to the road and moving along there?
Why did this not attract the attention of predators? I would expect egrets and crows to take advantage of this easy meal but actually only saw 1 night heron, and also a leaopard cat!

If anyone knows anything about this, I would be interested in finding out more!

Title: Re: Terrestrial fish at Mai Po
Post by 深藍 Owen on May 29^th, 2006, 3:03pm

john, is the following the fish you mentioned? took it last year Nov which quite a number of them "walking and partying" along the road next to AFCD office.

http://www.pbase.com/image/60947597.jpg

Title: Re: Terrestrial fish at Mai Po
Post by Allen on May 29^th, 2006, 7:02pm

Refer to Owen's photo, I saw one of this kind of fish in the grass land behind Edcation Centre Mai Po, about 6 inches long.

Title: Re: Terrestrial fish at Mai Po　米埔有魚陸上爬
Post by johnallcock on May 30^th, 2006, 12:15pm

The photo does appear to be the same sort of fish as I saw (unforunately I didn't have a camera with me!). Obviously the phenomenon has been seen by various people even though I have never seen it before.

Also, Owen's post suggests that it's usual for several come out of the same area of water at the same time (but why nowhere else?) In total I saw perhaps about 30 of these adventurous fish on Sunday afternoon, all in the same area.