Little Frogs Starting to Leave the Office Pond

Over the last couple of days we have been keeping a look out for signs of the first of the little frogs from this year’s frogspawn leaving the pond.  We had spotted one tiny froglet, still with a tail earlier this week (Friday), but up until now we had not found any evidence of frogs leaving the pond as fully formed, but tiny frogs ready to begin their amphibious lifestyles.

Little Frogs

To read the article about the froglet spotted last Friday: First Signs of Frogs about to Leave the Pond.

We had started to become a little concerned, as although we knew a number of the tadpoles had nearly completed their metamorphosis into tiny frogs, we had spotted several just a few days ago at an earlier stage of development. Their jaws had not started to form and as a result the head was still quite rounded.  For the last couple of days or so we had seen no sign of any tadpoles.  However, this evening one of the Everything Dinosaur team members spotted three tiny frogs, obviously this years hatchlings, whilst examining a container planted up with some French beans.

Little Frogs Spotted

It seems that some of the tadpoles have made it so far.  Hopefully, they will disperse in the back yard area behind the office and feed well enough over the remaining Summer months to be able to survive the winter.  With a bit of luck some of these tiny frogs will survive long enough to be able to return to our pond in a few years to breed.

Tadpoles begin to Disperse in Office Pond

Those tadpoles that hatched successfully have now begun to disperse across the office pond.  The heads of these little creatures, are now clearly discernable but no eyes or mouth can be distinguished as yet, in animals little more than one centimetre long.  The broad tails are permitting these tiny creatures to make short journeys as they spread out from the mass of spawn to take up residence in the rest of the pond.  We have observed a number of indviduals have made it to the far side of the pond and they are hanging onto large stones and debris in the shallows.  The majority of the tadpoles are to be found within the remains of the spawn, but we suspect that once they have exhausted their yolk sacs they will seek food and refuge elsewhere.  There is a lack of cover for the tadpoles (we cleaned the pond out in the autumn).  Hopefully, there will still be enough cover for the tadpoles to hide in although we accept that nearly all of them will perish over the next few weeks.  Most will fall prey to the other animals that inhabit the pond with them, the dragon and damsel fly nymphs are particularly voracious, but even blackbirds and robins can pose a threat to the tadpoles.

Office Pond Frogspawn Shows signs of Life

On Saturday 14th of March we reported that once again we had frogspawn in our office pond.  This is the second year in a row that frogs have spawned in our pond.  Based on our estimates we think that just like last year, the eggs we have in the pond have come from just the one female.  We are not sure whether it is the same female as last year, but it might be as we believe that the Common Frog (Rana temporaria) tends to return to the same pond each year to spawn.

To read the article about the frogspawn: We have frogspawn in the office pond.

We have kept a close watch on the frogspawn, and over the last few days or so we have observed that it is beginning to hatch.  The first tadpoles began to hatch on Wednesday 1st April, approximately 17 days after the spawn was laid.  The spawn last year began to hatch a little earlier but it was laid in a shallower part of the pond in direct sunlight and this may account for the slightly slower hatching this year.  We expect to see the majority of the tadpoles hatching over the weekend, although we note that the spawn is not as clear and healthy looking as it was last year.  Perhaps it is because the spawn has ended up in a deeper part of the pond, sitting on the silty bottom.  Those tadpoles that have hatched already, have a distinctive head end, but their tails are not able to propel them very far at the moment.

In the autumn, we all got together and had a lovely afternoon clearing out the blanket weed and generally cleaning the pond.  This has left the pond with little weed cover.  Hopefully, the tadpoles will be able to find plenty of cover to help them avoid predators.  The absence of cover may permit us to observe the tadpoles in more detail this year.

To view the article about 2008 hatching frogspawn: Frogspawn beginning to hatch (2008).

The pond seems quite healthy, we have noticed a lot of snails eggs and the water boatmen have been very active.  We also observed our first pond skater of the season.  Hopefully, our pond clearing has helped maintain a healthy, balanced ecosystem.

Moving Frogspawn

We were checking back on last year’s notes and articles made about the frogspawn in our office pond.  Interestingly, the frogspawn was laid on March 16th last year and this year it has arrived a little earlier.

To read last year’s article about the sighting of frogspawn: We have frogspawn in the office pond!

Yesterday we commented upon the folklore which stated that depending on where in ponds frogs spawned was an indicator of either a wet or dry spring.  If frogs spawn in the shallow margins, this, according to the old-time sayings of country folk, meant that the spring was going to be wet.  If frogs spawned in the deeper parts of the pond, this meant that the spring was going to be dry.

Our frogspawn has moved, it has sunk down to a deeper part of the pond.  How it has done this remains a mystery.  The eggs are inert and cannot move themselves, so we suspect that either the natural buoyancy of the spawn has changed and the spawn has sunk or the activity of the frogs in the pond may have moved it.  It was quite windy last night so there is a possibility that the wind may have had an effect on the spawn and caused it to move.

So our spawn has been transferred from a shallow part of the pond to a deeper part, so much for the folklore, or did the frogs change their minds over the weather forecast?