Jon Cranfield

Archive for October, 2010|Monthly archive page

beetles are increasing in number….

In Uncategorized on October 12, 2010 at 5:14 pm

A night time survey last night revealed that there are four water beetles in my little garden pond. The mayflies are growing nicely and most of the fly larva have started to pupate and hatch out.

The pond has another dusting of grass cuttings which seem to provide some good habitat for the inverts in the water column. The water is crystal clear. The plants which have taken include some grasses, rushes and garden moss.

The pond levels are gradually getting lower after the deluge of rain we had previously.

The exposed liner has been covered with pebbles and gravel. Fingers crossed that louise feels that the pond is not too ugly now.

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Is the common frog on the verge of dying out?

In Uncategorized on October 11, 2010 at 8:43 am

According to a Telegraph article (3rd October) it is feared that Ranavirus may have the potential to wipe out the common frog at least in localised areas.

Jeremy Briggs on his garden pond blog has pointed to the NARRS survey which revealed that over 50% of the ponds surveyed for amphibians recorded the common frog. I assume that this is highlighted to illustrate that frogs are not dying out.

The situation in garden ponds it seems from the limited surveys that I have been involved in over the last ten years seems to support the view that garden ponds are the stronghold for the common frog. Common frogs were recorded in over 80% of garden ponds in surveys carried out in 1996, 2000, 2001, 2002, 2003 & 2004. The focus in these surveys were urban and suburban areas and not in countryside ponds. A similar number of ponds were surveyed and a much higher occupancy was detected. Do we really know what the status of the common frog actually is in the UK?

Finding breeding frogs in countryside ponds is all very well but we have no idea of the population which is breeding in those ponds.

My old garden pond, in Eastleigh, had around 100 frogs breeding within It (based on peak spawn counts). This is somewhat surprising as the pond was only 1 metre in diameter. But the spawn count was over 45 and so for each clump corresponds to a female and for each female ther has to be a male and thus you get an estimate of approx 100 adults.

My old pond was designed as a wildlife pond and was not a standard garden pond. It was very good for frogs confirmed by the masses of froglets which emerged over the summer months.

Froglife are quoted that they have had reports of 30 to 40 dead frogs in garden ponds. In my pond that would have been 50% of my frog population. However in much larger ponds there tends to be many more frogs. An old employer of mine used to have a garden pond managed for frogs which had at least a population of 800!

A die off of around 40 frogs would be insignificant in these ‘super frog’ ponds.

There are many unreported ‘red leg’ cases and probably a similar number of frogs bouncing back after these die offs.

With an estimated 2 million garden ponds that is a very significant ‘stronghold’ but is probably one of the main sources of Ranavirus coming into the UK. So will frogs be killed off completely?

With the million ponds project the balance may be readdressed in clean water temporary ponds…

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much more rain!

In Uncategorized on October 3, 2010 at 9:31 am

The pond is now thoroughly drenched with rainwater. I have placed gravel around the edge of the pond to try and reduce the look of exposed liner (a moan from the wife). The water level has flooded over the gravel which will provide a different habitat for any new pond inhabitants.

The mayfies are getting larger and are more noticable. Some other larval animals have been spotted and could be water beetle larva (fingers crossed).

I spotted that froglife has had an event apparently tucking in the toads for their hibernation. With the mild and wet weather the toads would be far from going into hibernation.

The local town has a toad population which is part of toads on roads. The population has declined over the last ten years. So much so it seems that the road crossing will be denotified.

My pond has been designed as a clean water pond for wildlife. It is also designed for common frogs as they need small shallow ponds which have been lost in the countryside.

My last pond in my former address had over 80 frogs breeding within based on the peak spawn clump counts over three years.

The new pond has good shallows which will be nice and warm and allow the tadpoles to grow and group as a defence against predators….

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