Showing posts with label Ed Bennett. Show all posts
Showing posts with label Ed Bennett. Show all posts

Friday, 19 October 2012

A Yellow-browed Warbler and loads of Sleepy Dormice

Today I had a busy day planned doing some more hazel dormouse training for the rangers at Titchfield Haven. I had considered doing some ringing prior to the training, but instead opted for an extra hours slept....what a mistake! As I was just rounding the double bend at the back of the haven I received the image below from Ed Bennett, one of the rangers I would be training. Given the number of yellow-browed warblers in the country at the moment the biggest surprise was that none had been caught, well not any more, I will be down there ringing tomorrow so maybe there will be another, or even something better!

Yellow-browed Warbler, Titchfiled Haven (Ed Bennett)

Since we were at the haven we started our dormouse survey by checking there first. There are a mixture of tubes and boxes around the ringing area, with a few bird nest boxes thrown in for good measure. The dormice aren't really choosy about which box they use, as they have been previously recorded in all of them, not this time though, a few old nests was all that was on offer. The ringing area has been saturated this year so it not surprising we recorded none here, its probably just too wet.

Hazel Dormouse

Our next site was to the west of Titchfield Haven, a site where we recorded five animals last year, and one earlier this year. This year we got off to a great start with three individuals, one adult female and two juveniles, in the first box. These were a feisty bunch with one of the juveniles appearing not to have read the dormouse handbook, and duly gave Nick a nip on the finger. The third box was similar to the first, with three individuals in it, this time it appeared that there was an adult male and female, and one juvenile. Two more active dormice in another box, before we came across the two below.

Two Torpid Dormice

The Hazel Dormouse is a lazy species spending around six months of the year in hibernation, in a woven nest at ground level. But even in the summer months they will enter torpor, particularly when its raining or their food supply is short. When torpid they can be readily handled without waking, and can even be heard to snore!

Torpid Dormouse

The Hazel Dormouse is strictly nocturnal and predominantly arboreal, and during the summer is active from dusk until around 3 - 4 am. During September and October, when it is fattening up for hibernation they will be active all night.

Torpid Dormouse

Prior to hibernation adults can weigh between 25 - 35 grams, with the heaviest recorded in the wild weighing 43 grams, juveniles weighing less than 12 grams will be unlikely to survive the winter. Today we recorded weights of between 16 - 27 grams, so all of them appear to be in good health, and will hopefully be well placed to survive the winter.

Torpid Dormouse


By the end of the session we had recorded 11 dormice in five nests...our highest total ever, and found inactive nests in other parts of the site where we had previously recorded none. This is excellent news all round, since it would seem to suggest that the species is doing well despite the very changeable weather we have had this year. It also shows that the management of this particular woodland by the Rangers at Titchfield Haven is also benefiting the species, long may it continue. The plan is to register this site on the National Dormouse Monitoring Programme so that the population can be studied and its long term survival can be maintained at this site.

Sunday, 5 August 2012

Cetacean Corpse at Titchfield Haven

I had a call this afternoon, from Ed Bennett, a ranger at Titchfield Haven, that a cetacean corpse had been washed up on the beach at Hill Head. Ed suspected that the corpse was that of a Harbour Porpoise, and sent me a picture which seemed to suggest that it was, but being the sad person that I am, I decided to go and take a look.

Harbour Porpoise Corpse

The corpse was quite badly decomposed, and did wiff pretty badly, but still it was possible to make out what it was, although on I first impressions I did think that it might be a Common Dolphin.

Harbour Porpoise Corpse

The major difference between dolphins and porpoises is that dolphins have a pronounced beak, whereas porpoises have no beak and a blunt snout. As is possible to see below this corpse lacks a beak and has a blunt and rounded snout. Dolphins also have a more pointed and angled dorsal fin, whereas in porpoises it is blunt and less angled. The dorsal fin on this corpse did look quite pointed, although looking at the trailing edge, it is not as concave as would be expected in Common Dolphin.

Jaw Showing Rounded Snout

The dried and cracked tail stock is evidence that this corpse has been floating around at sea for a while, and I suspect it has drifted into The Solent from The English Channel. The colouration of the tail stock, with dark grey upperparts and pale underparts, was again consistent with Harbour Porpoise. Common Dolphin has an hourglass pattern on its flanks and therefore it should still be possible to see the two-tone pattern.

Dried and Cracked Tail Stock

Many Harbour Porpoises are killed each year, either as by-catch from the fishing industry or by collision with shipping vessels, so I was keen to see this corpse and see if there was any evidence of either. I could see no evidence of net entanglement or propeller cuts, so it maybe that this individual died from natural causes, but unfortunately we will never know.
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