The other day we were diving in a fresh water sink in New Mexico. At the top of the sink is vegetation that dies and drops extremely fine, loose organic débris, almost a dust except that each piece of silt is like a fine needle perhaps 5 mm long. Every ledge has a coating of this silt, and the slightest water movement disturbs it.
Some of the ledges have a clay layer, and in the silt that covers them crystals grow. The are like flat translucent knife blades, purple at one end and and moving to clear on the other. My buddy believes they are gypsum--I know nothing of this sort of thing. My buddy and I were hanging out at one of those ledges, looking at the crystals poking up through the silt. We were at a depth of 150 feet--very dark. Fine needles of the silt drifted in front of us. Then I saw one of them move unnaturally, against the flow. I watched carefully, and saw that it was not silt; it was some kind of an animal. Eventually I saw perhaps a dozen. I had to look carefully, for the were very small, perhaps a couple MM long, and silvery white. They hopped like fleas, and when I showed my light on them, they burrowed into hiding. I have good distance eyesight, but I need reading glasses. I tried to focus my 2X lens on my mask on one, but it did not help much. I could see briefly hind legs that looked something like a cricket's, with "knees" pointed out ward.
I later learned that my buddy had seen them too, and that is the first time he has ever seen them after hundreds of dives on that sink. (I am a relative newcomer.) He had no idea what they were. The next day I did not dive, but he returned to the same location with someone else. They didn't see any.
Any ideas?
Some of the ledges have a clay layer, and in the silt that covers them crystals grow. The are like flat translucent knife blades, purple at one end and and moving to clear on the other. My buddy believes they are gypsum--I know nothing of this sort of thing. My buddy and I were hanging out at one of those ledges, looking at the crystals poking up through the silt. We were at a depth of 150 feet--very dark. Fine needles of the silt drifted in front of us. Then I saw one of them move unnaturally, against the flow. I watched carefully, and saw that it was not silt; it was some kind of an animal. Eventually I saw perhaps a dozen. I had to look carefully, for the were very small, perhaps a couple MM long, and silvery white. They hopped like fleas, and when I showed my light on them, they burrowed into hiding. I have good distance eyesight, but I need reading glasses. I tried to focus my 2X lens on my mask on one, but it did not help much. I could see briefly hind legs that looked something like a cricket's, with "knees" pointed out ward.
I later learned that my buddy had seen them too, and that is the first time he has ever seen them after hundreds of dives on that sink. (I am a relative newcomer.) He had no idea what they were. The next day I did not dive, but he returned to the same location with someone else. They didn't see any.
Any ideas?
