Saturday 25 April 2015

Encountering the "Kerry" Toad

Today I was out around Castlegregory in search of an amphibian I have wanted to come across for some time.
The Natterjack toad pond today.
The Natterjack Toad is the only native Toad species found in Ireland. It was first observed in 1805 around Castlemaine harbour, the tidal body of water found between the Dingle and Iveragh peninsulas just East of Inch strand. Since then there has been some localized extinctions and as such the Natterjack population now resides in a few heavens to the North and South of the Dingle peninsula.
This Toad species is believed to have colonized the country naturally after the last ice age which ended in and around 11,000 years ago as they share some genetic similarities with the nearest Toad population over in England.
Now you might be thinking, whats so great about this Toad?
Well it is unlike any of the three other amphibian species found on this island nation. The more widely known frog might on its preface seem similar to the Toad but its not by a long shot!
Physically the Natterjack is a much broader beast than the streamlined frog, they crawl along like four legged cowboys in stark contrast to the frogs fondness of leaping and they are also coloured differently with the toad possessing a diagnostic white line running along the top of its back. Even the toads tadpoles differ from the frogs, the latter being inundated by varying shades of browns where as the former is jet black and also a much broader built bundle of flesh.
The habitat of choice for this amphibian is a very surprising one for a freshwater inhabitant.. by the coast! They utilize the small freshwater ponds nestled in amongst the dune systems of Castlegregory along with and suitable bodies of water within their range.

The Natterjack's home-range has probably become reduced due to the increase in agriculture over the past century BUT there is a scheme in place nowadays encouraging local land owners where the toad is present to dig ponds, maintain them and not use any chemicals which could effect the toads which would also forage on land. The areas around the ponds are usually grazed by cattle in particular and this system has yielded results as last year was a bumper year for the counties population.
At the waters edge where the smaller tadpoles were.

Back to today, I discovered where to find some of these ponds and decided to chance my arm. April is the peak time for breeding and I initially wished to head back to Castlegregory's dune system to hear the chorus of Toads in the ponds and maybe catch sight of one or two in the flesh. This plan changed however and I arrived during the day where I could actually see where a pond was positioned.
Judging from the map of the ponds I obtained this morning, the roads position and the local geography of a particular stretch of dunes I quickly identified the position of a pond which was evidently the cause of a sudden submergence of the ground between two dunes.
On further inspection the pond itself was located. I found it very odd that such a body of freshwater could be found so close to the sea to both the East and West along with being lined by sand blown in from either of the two surrounding bays, it was akin to the surface of Mars!
It didn't take long to find the first signs of the toads as I peered into the ponds shallow waters for the first time I spotted some relatively small toad tadpoles near the waters edge. Once they could see my figure towering above them most made a break for the safety of some nearby submerged vegetation while others played dead. These tadpoles are loaded with toxins which do not agree with the micro predators found cruising our bodies of water and as such they have an advantage early on in life.
Some small tadpoles over the sandy bottom.
Carefully stepping forwards along the left side of the pond I kept a careful eye out for any lingering adult toads both on land and in water, t didn't take long to stumble upon my first toad albeit a bit more static than what I was going for but I'll take it. The thin and slightly wrinkled body of a Natterjack lay outstretched just at the waters edge. It's dark green back blotched by darker polka dots was raised skywards while it's unique back stripe remained clearly visible. Its left fore limb was tucked underneath its body and its eyes were shut. I think this individual was a female as evident by some strands of spawn near its hind legs, in the water nearby, wrapped around some vegetation lay even more coiled spawn so it appears this individual has done it's bit for the next generation. I do not know what happened to it but there was evidence of an even more toasted toad further up the shore line which may suggest that some animals expire after spawning.
My first rather lifeless Natterjack
Continuing the tour around this hidden oasis I came across far more developed tadpoles, one of which may even be in the early stages of developing legs!
While watching these larger tadpoles I heard a call completely out of tune to the circling gulls and singing skylarks. I left off short raspy sounds all of which came from a patch of marrm grass of the closest dune over looking the pond. I inspected the area to no avail due to the grasses thick coverage and while doing so must have spooked this individual which was undoubtedly a male toad calling out to any potential suitors.
Some strands of spawn weaving between the vegetation.
I doubled back around the pond for a final look before leaving to discover vast strains of spawn intermingled with the grasses and water mint amongst other vegetation present in the pond. The individuals occupying the spawn were at different stages of development so they were laid on different occasions which I find to be very unusual to the system used by frogs where they all congregate at once, Natterjacks however seem to be more particular in they're ways.
All in all I can't complain with the days results but I will be back for more very, very soon!
Looking down to the pond and on the Brandon bay further West.