Circle of Life in the Backyard Pond

We have a modest back yard pond.  I built it years ago so we could enjoy a bit of nature out there.  But not too much nature.  It had become a great place for mosquito larvae to wriggle about and I was tasked to deal with the situation. Not being one to start tossing poisons about, I just went to the local bait shop and got a scoop full of minnows.  My fisheries biologist son suggested a type called "fatheads" would survive nicely and eat lots of mosquitoes.

Of course there were a few who did not survive the transition, but my rough count suggested that there should still be a dozen or so swimming about consuming mosquitoes.  One day later I saw three.  A week later it was down to one rather well fed but lonesome fathead.  My grandson suggested that minnows are very good at hiding but I did have some suspicions.

Second attempt then.  Back when my boys were youngsters we'd go down to the rocks below the local hydro dam.  In the spring there would be high water but when it receded there were ponds that I recalled being full of tadpoles.  And yep, still true.

Not my back yard pond, this is nicer.

Those little black things trying to hide, that's them.  These are the tadpole version of the American Toad, which I will continue to call Bufo americanus despite a recent name change.  I considered this a genius idea, the tadpoles themselves eat small bugs and then the adult toads might stick around and eat more.

This looked promising.  There were thousands of them and the water quality they were thriving in was way worse than our pond.  So I scooped up a bunch.  Some were tiny, others approaching toadlet status.  As seen below some of them got legs but so far don't know how to use 'em.

And here actually is our back yard pond, new denizens carefully transitioned into it.  I don't know much about the buoyancy properties of defunct tads but eight hours in all I could see were apparently happy, live tadpoles eating algae and bugs.  I put the cement frog there as a sort of protective totem.  Bufo the Great in the eyes of the tadpoles when they first emerge as toads....

The Tadpole Colonization project was accomplished on the longest day of the year.  That means the shortest night.  So when my wife went down for coffee at first light an interesting sight was beheld....

Raccoons!  Notorious eaters of pretty much everything.  The Mystery of the Fatheads solved.  I hope the tadpoles are craftier...
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Update.  Most of the tadpoles seem to be gone.  I don't think they are better at hiding than minnows.  Alas.