• last year

Category

🐳
Animals
Transcript
00:00 Beneath the tar, on the valley floor, rare pools of water teem with life.
00:06 Freshwater fish.
00:09 Only three species survive in the Al Hajar mountains, and this one is the Oman gara.
00:16 They endure only in isolated permanent pools of the wadi.
00:21 These tiny fish get by, scraping algae and any other detritus from the rock walls of their watery prison.
00:30 Their survival depends on much-needed rainfall to replenish their shrinking refuge.
00:39 But rain is unpredictable in Arabia.
00:45 Some years it does not rain at all.
00:49 Then, some pools will dry up, and the fish in those will die.
00:56 80% of the water that falls in the mountains will evaporate.
01:01 The rest quickly runs off the hard ground and into cracks in the rocks.
01:07 Rain here in the Al Hajar mountains is erratic and unreliable.
01:14 A mere six inches falls each year, and it comes in only a few short, heavy bursts.
01:25 The rain runs off the mountains, building momentum as it descends to the valley floor.
01:33 Light rain can quickly turn tranquil pools into rapids.
01:40 While toads stay clear, the rushing water has the opposite effect on the garra fish.
01:50 This is the opportunity they've been waiting for.
01:57 They have a mysterious, instinctive drive to always explore upstream,
02:04 driven by the need to expand their territory.
02:11 They take whatever opportunity they can to forge into the current.
02:17 This is how the species can recolonize areas where the previous inhabitants have perished.
02:26 But this is not just fish swimming upriver.
02:30 These fish undertake an epic climb.
02:37 Their sucker mouths, which usually scrape algae from the rocks,
02:41 become anchors, securing them against the fast-flowing water.
02:51 A group inches its way up the rocks.
02:59 The fish must stay within the splash zone in order to breathe,
03:03 but stay out of the main flow to avoid being washed back downstream.
03:15 The fish can travel up to nine feet, up sheer rock faces.
03:23 For those that make it into new pools, there are fresh possibilities,
03:29 food and a new territory to colonize.
03:38 The stress of the journey is also thought to trigger their spawning behavior,
03:42 to make sure every new pool is quickly populated by the pioneers.
03:49 Their sticky eggs will settle in the gravel to stop them washing back downstream.
03:56 (Music)

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