We have quite a number tadpoles in our pond that have not developed into froglets. They should have done so by the this time of year, having been released from the spawn in late March. I have noted this in previous years. There are always a few who remain tadpoles, but there are more this year. It may be because there was so much spawn in early spring, resulting in more tadpoles than we have had before. And so, more who did not complete their development.
Why do some tadpoles not become froglets?
Sussex Wildlife Trust say:
‘Normally tadpoles will develop into young amphibians and leave the pond during the summer months but if conditions aren’t right, they may choose to overwinter in the pond and finish their development the following spring. This could be seen as an advantage: as long as these tadpoles survive the winter, they will have a head start next year and have much more time as froglets to feed up before winter arrives again.’
I query the word ‘choose’ as it is not a choice for a tadpole to develop legs and lungs or not. Peter Pan could decide not to grow up, but Wendy and her brothers were victims of their hormones. They grew up, much to Peter’s despair.
Sussex Wildlife Trust posits some possibilities for Peter Pan tadpoles. There may be a shortage of algae, their food, making me wonder if we should be quite so efficient in clearing away filamentous algae. Then, there’s cold weather, another factor, and an unusual mass of tadpoles where competition for food leads to starvation and inhibited development.
In our pond, I have noted many tadpoles feeding on the butyl rubber. There’s some algae on it for sure, but enough? Do they end up filling their guts with rubber?
In the end, it is conjecture. I have looked on line but not found anyone who has done experimental work on the reasons why a minority of tadpoles don’t grow up.
We have had a succession of showy tree blossom. First, came the pink cherry blossom in late April, before the leaves even, followed by the white cherry blossom. The two just crossed over, with the pink fading as the white came to the fore. Then came the hawthorn in mid May, dying over the past week. It was a fine display, a powerful sprinkling, which I saw massed in the hedgerows last week on a country walk in the Chilterns. And now, by the gate we have clusters of elder blossom. The creamy white clusters of tiny flowers have a strong aroma which make a delicious cordial. A week or two of flowering, then green berries follow, becoming deep purple, near black, by late summer.
We have two other large trees, the sycamore and the silver birch. Both have green flowers, you really have to be looking for, amidst the leaves, to see them at all.
There are two corncockles in the wildflower bed, the most stylish flower in the garden, an under appreciated, Cinderella plant. Unlike Cinderella, but like Millwall, they don’t care. Tall with purple elegance and swish green scarves, it was common in wheat fields in the 19th century but modern herbicides almost wiped it out. In 2014, the Daily Telegraph went into a panic over the BBC, with Kew, distributing wildflower seeds, including corncockle, which it declared was poisonous. Well, so is ivy, laburnum, foxgloves, hellebores and lupins. Though, if you decide to eat our corncockles in a sandwich, it will likely make you sick, should you be daft enough. And a spoilsport.