Saturday, 29 September 2007

3-in-One Day

I must have been a teenager, ten years or more ago. I really can't remember the time last I encountered 3 birds for my life list on one day. What to say but god bless the man who invented bird sightings websites!

First target today was the long-staying juvie Long-tailed Skua in the south of Nottinghamshire. The bird was found two Mondays ago and still this morning there it was, staunchly quartering the stubble field its made a home of for two weeks, harassed only by the occasional Carrion Crow. Stunning bird too, the skua, in a sort of chocolate duffle coat plumage.

Alas, my photographs were distant.
Video 1 - Video 2

Much closer pictures can be found here, (apparently) taken with the landowners consent. That was the problem with this skua, every birder who traipsed the half mile out there knowing it to be a relatively tame individual had to muster all their self-restraint and hold back from blustering across the field for a better look. It was easy to see how sometimes birdwatchers pose a trespass nuisance, though I was surprised to find on a Saturday morning it just was the girlfriend and me with the bird to ourselves, maybe everybody else had already seen it?
Actually no, after pointing the bird out to a couple of new arrivals, it was time to make haste for Rutland and two more of the day's targets.

The scene at Rutland Water.

First stop was the Lyndon Reserve, overlooking the Manton Bay area of the reservoir. Out there among the flurry of Commic Terns and Black-headed Gulls, was what we'd come for, a solitary juvenile Sabine's Gull, hawking and nipping up insects from the surface waters. As you can perhaps see here, the grey-white-black pattern of the wings is so very distinctive that you could call it from half a mile off. And here's a thought, it came all the way from Arctic Canada, or even Siberia!

Third target was Red-necked Grebe, which I thought we'd missed after failing to find it in Manton Bay, where two days of reports had it located. Then having retired to pick up some waders at the Egleton Reserve, at 5pm just before turning home there it was, in the far distance from the last hide along, showing just enough plumage information to distinguish from a GCG. It was the broad dusky neck that did it, the Great Crested Grebe always has a pure white throat at all times of year.
So the moral of the story is never lose hope as long as you're still out there!

Other notables for the day; Little Gull, Artic Tern, Curlew and Green Sandpiper, Little Stint, Ruff, Little Egret, Black-necked Grebe, Whinchat.
64 species for the day, I'm sure several easy ticks overlooked in the hunt for the spectacular.

Some thumbnails:

Spot the Skua!

Rutland waders.

Green Sandpipers.

Little Egret.



Red Admiral.

Finally, a couple of local spots, an Arctic Tern at Kings Mill Reservoir, one of several that passed through the county that day, and at Pleasley Colliery a Yellow-legged Gull. One of the individuals that roosts at Carsington Water maybe?

Oh, and just nipping out into the garden I heard a flock of Redwing going over. This time of year, pop your ear out at night and you could get them just about anywhere.

Thursday, 13 September 2007

Carsington, Pleasley and the Green Lagoon

Fields beside Carsington Water

Things are settling down for me at the Carsington ABB events, a routine neatly developing. The vibe was pretty good this week, a quieter day so we could spend more time on each visitor and impress on them all things wonderful about the birds. I didn't stick around to wait for the actual figure, but it's clearly we had a fair number of people signing up not only for the RSPB newsletter, they were going for full membership too. What to say other than, SCORE!

The water level is very low at Carsington which seems at odds with the summer we've had, especially since her sister reservoir at Ogston is absolutely brim full. No complaining from us though, low levels means more exposed mud, and autumn winds permitting a plentiful area for passage waders to feed. That said, the only waders we had on Tuesday were Lapwing and one elusive Green Sandpiper.
Up on the hillside the Little Owls dutifully showed well through a scope, a cosy threesome of eclipse Red-crested Pochard kept in broad view (with at least two more males spread elsewhere), a juvie Common Tern briefly passed through, a pair of Raven showed over distant woodland and a female Shoveller was a blink and you missed it bird for the day list. We ended with 42 species from the Wildlife Centre, which is a about par.

Pleasley Pit

Back at home the local rounds on my bike turned up a Yellow-legged Gull at Pleasley Colliery Nature Reserve. The small lake up there has always been a hotspot for local rarities, although these days with increased visitor numbers - mostly dog-walkers - the nearby birding fraternity seems to have rather turned interests away from it, many grumbling of the constant disturbance. For me it's a pleasant bike ride and at the site I've picked up Ruff, Wheatear, Yellow Wagtail and Little Ringed Plover, so it's clear to my mind it's still worth a regular look, and I think quite under-watched. For the two years I've been visiting I could count on the fingers of one hand how many occasions somebody has been in the members-only bird-hide.

On the other side of town King's Mill Reservoir looks in poor health with another summer bloom of algae. I'll let some minutes from a local council meeting explain the problem:

'Ashfield is not noted for having many large bodies of water, which makes it all the more important that we conserve and protect those few that we have. In Northern Ashfield the past few years have seen a massive problem arising due to repeated seasonal growth of algae, in Kings Mill Reservoir for example, and this problem has repeatedly to be coped with.

The problem arises because of an upset to the very delicate balance between algae, fish, and bacteria in the water. These three denizens of natural water depend upon each other in a triangular relationship which can be upset by pollution.

Algae -- a collection of microscopic plants -- use sunlight to photosynthesise food from nutrients. These nutrients are provided by the bacteria in the water which act upon the waste products from fish, converting them into a form which the algae can use as food. In turn the algae provide food for the fish, and they also serve both the fish and the bacteria by oxygenating the water as a by-product of their photosynthesis.


What causes the upset is that additional nutrients get into water through pollution, and this causes massive growth of the algae, producing what is often called an algae bloom. This can spread over the surface of the water, and can be made worse by the growth other surface plant life.

It might be thought that this is actually a good thing, for after all it provides more food for the fish, which might therefore be expected to thrive. Such is indeed the immediate effect, but it does not last. The algae grows to such an extent that there is too much of it, with layers of algae growing below other layers. The upper layers of algae shelter the lower layers from sunlight, and the latter cannot therefore photosynthesise their food. They they die. The bacteria in the water then act upon the dead algae, and in the process they use up masses of oxygen from the water.

This de-oxygenation caused by the action of bacteria upon the dead algae obviously results in the death of the fish, which needs that oxygen. The dead fish sink to the bottom, where further bacterial action changes the dead matter into sludge, and further depletes the water of oxygen.

This sludge can, in extreme cases, turn what was once a living pond or lake into actual swampland.'

Periodically new aerating rafts have been placed in areas where road run-off and other sources of pollution reach the reservoir, though clearly that measure just doesn't work well enough. Looks like there are no easy answers to this problem.

For now the bird life can tolerate the algae, although it has been quiet this week. The best bird yesterday was a Snipe for example. Still if you have birds you're never short of action, and the highlight was a meeting of minds between a Cormorant and a Heron...

In the end, the Cormorant won.

Sunday, 9 September 2007

Owls of Intrigue

Nipped down at last light to King's Mill Reservoir this evening, wondering what might turn up in the roost. Recently a 1st-year Med Gull has been reported, which poses both a nice tick and an ID challenge in a gull roost of a few hundred BHs. No luck tonight, and none earlier in the week.

What I did find on Friday in good light was a Tawny Owl leaping away from Barn Owl bridge. This was surprising first because obviously Barn Owls are associated with it (since they bred there), and I've never seen Tawny Owl around any manner of concrete or rock artifice - certainly never heard of them roosting in man-made structures. The whole thing is puzzling to say the least.

I'm left to hypothesise that the Tawny was attracted to the activity of the Barn Owls, particularly since I saw a Barn Owl back at the nest site this evening. Some Tawny behavior is still little known, indeed it wasn't until relatively recently it was documented that they caught fish, so who know what else they could get up to?
What I am certain of is that I saw something special.

Tuesday means an ABB event for me at Carsington this week, so expect a post.

Thursday, 6 September 2007

A Regal Reservoir

You can tell the summer is waning when Kingfisher return to the waters of my local reservoir. It has been my experience that they are a regular sight there from late summer until the early Spring, evidently retreating back up (or down) river to nest in quieter banks at that time of year.
Okay, so the video is hardly David Attenborough, nice clear recording of the call though.

In other bird news, I noted a House Martin nest still in occupancy during a walk into town today. This is late, though hardly unheard-of for a species that often only nests successfully once in its lifetime (much as we'd like to imagine the same birds return to the same nests year after year - they don't). It is perhaps because of that that these hirundine will have two or even three broods during a summer, hence the tardy would-be fledglings still up there - probably not the first effort of the year.

Oh and one tip. I hate to be a pedant about this, but to the birder I saw, who was attempting to lurk in the overgrowth whilst wearing the brightest richest most vermillion red t-shirt I ever did see, there are better choices of attire for birdwatching!
I mean comrade, I'd like to think there is a time and place, that said, for your red shirt it really beats me when and where!

Tuesday, 4 September 2007

Brief Roundup

It's a been a quiet week, the highlight was a Raven being mobbed by a pair of Sparrowhawks at Ogston Reservoir. Doubly exciting for me because I cycled out there, making the big crow #108 for my carbon neutral list.
You know it sure is fun to be keeping a new lifelong list I can regularly add to, well, at least for now.

As part of their eastward spread, that area of central Derbyshire is a great spot for Raven, just enough upland and just wild enough too for a thin breeding population. It has to be thin really, Raven territories are BIG and they keenly exclude all others of their own species.

Otherwise, like I say, very quiet, so I'll direct you to an interesting blog entry about Blue Tits feeding their chicks brain food - spiders containing an amino acid called taurine, which helps to develop the mental faculties of the young. Read more here, it's one of those, who'd of thought(?) pieces of research.