Monday, 11 April 2016

Egg of Newt & spawn of Toad

Smooth Newt (Lissotriton vulgaris). Male.
Without the buoyancy of the water, the crest, which runs along his back, is folded over onto his body/tail

Apart from mangling a bit of Shakespeare, last week, I slid into the watery world of the Smooth Newt (Lissotriton vulgaris). This is the UK’s most common and widespread newt species. In terms of its length (up to 10cm), it sits comfortably in between the UK’s smallest newt, the Palmate Newt (Lissotriton helveticus) and the UK’s largest and most protected newt, the Great Crested Newt (Triturus cristatus). All 3 native species are fairly widespread and it seemed plausible that we might have at least 2 of the 3 on BMT land. The only way to find out was to get stuck into a proper, grown-up newt survey.

Close by, local RSK ecologist, Jess Breeze, and 3 bright, young Master’s students, found themselves in need of a convenient training ground. It was a match made in Resource Management heaven. A plan was struck, collaborations agreed and wellies cleaned. We even had an average overnight temperature of or above 5°C on Thursday, making bottle trapping a possibility. All that was missing were the slinky, lizard-like amphibians.

There are four main surveying methods: torching, bottle trapping, netting and locating eggs. They’re all fairly self-explanatory but there’s a whole lot more info here, if you’d like it.

Bovingdon Brickworks, lined pond

We started at Bovingdon Brickworks. The torching count was a complete surprise. Although I’ve seen frogs here, I hadn’t expected newts. We tallied 28 male and 30 female Smooth Newts. It was crawling with life!

Following a count of the adults, it was time to look for eggs. This entails a search for vegetation which has been folded over by the female, using her hind feet, to protect/house the solitary egg in its jelly sack. A single length of vegetation can be used more than once, creating a concertina appearance.

Spot the folded grass stem

Smooth Newt egg, 1) inside the grass stem 2) revealed 3) up close

Over the course of a breeding season, she’ll lay a phenomenal 200-300 of these and they will be the offspring of numerous different males.

The eggs are tiny, approx 2mm in diameter.

The fun didn’t end with the egg hunt. Oh no, after that it was time for bottle trapping in Hay Wood, Westbrook Hay.

8/4/2016, 9am, Hay Wood pond. Bamboo poles mark the location of bottle traps, set 2m apart, 12 hours previously

Bottle traps: 1) in the pond, 2) out of the water, showing angle of submersion, which enables the formation of an air bubble inside to provide trapped newts with oxygen

Our trapping, torching and egg hunt success was less impressive at the Hay Wood pond. Just 1 male and 1 female in the bottle traps. 3 spotted the previous night, torching (the water was too murky, following the heavy rain). No eggs found.

Bottle trap results: 1 female and 1 male Smooth Newt plus a well developed frog tadpole (back legs starting to sprout)

Having never surveyed newts before, it really was a fascinating and fun process. When Jess showed us the telltale sign of the presence of eggs and then unfurled the grass stem, it was one of those moments where you couldn’t help but gasp and smile at the ingenuity of nature. Sure, less than 1% of all the eggs laid will make it to adulthood but the fact remains, delicate, tiny and vulnerable organisms do survive. Nature may be red in tooth and claw but it is also structured in such a way as to sustain a life when it is at its most defenceless. To be aware of that is to experience, and to be enveloped within, a unique kind of limitless beauty. Many thanks to Jess and her colleagues for the opportunity.

Finally, in other news, Toads have spawned at the Brickworks. This is my first record of breeding Toads in the 3 years I’ve been walking the site. I’ve never seen so much frog and toad spawn as I have this season. Perhaps the mild winter meant that significantly more adults survived to breed another day…

5/4/2016, Brickworks breeding Toads #1
[Top Left] flooded dell, arrow points to spawn. [Top Right] spawning Toads around that vegetation
[Bottom Left] Toads. [Bottom Right] strings of pearls aka spawn in adjacent dell

P.S. Before I forget, I’ve added a new widget to the top of the left side-bar. The title will likely vary but for now, it links to a post from “this time last year...”.

P.P.S. Brickworks butterflies so far this year: Small Tortoiseshell, Peacock, Comma, Brimstone.
Bird highlights last week: a flock of 6 Lesser Redpoll feeding in a willow at the Brickworks. Amongst them, 3 or 4 males nearly in full breeding plumage - their bright red foreheads now complemented by gorgeous rosy pink chests. In Hay Wood, a pair of Treecreepers at chest height, no more than a few metres away. Exploring tree trunks together and occasionally singing. Any day is improved by a decent sighting of a scuttling creeper.


#1 If you’d like to see each of the photos more clearly, click on the image, then right click and select “open in a new tab”. In the new tab, click on the image to enlarge.

2 comments:

  1. It sounds like it was an evening of discovery. The newts are quite beautiful. (In a newty way) Fantastic photos as ever and an interesting write up. I love the picture of frogs. I'm glad you've seen some tree creepers. From ARF

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