Thursday, 14 December 2017

The sum of all parts of the quarry (4): non-passerines

This December, the two roost counts at Berengrave are far apart, thanks to surgery. Time to muse on what gets counted. OCD muppet that I am, I try to count everything. Results? All 'normal', but all fascinating, and helping to refine my personal views on the local populations.

This is just one small relatively insignificant, often overlooked, reserve. But look hard enough and there's enough question to keep a birder (even a bed-ridden post-op one) happy.

The non-passerines

Grey Heron
A conversation with one of the rangers a couple of years backwent something along the lines of 'Grey Herons roost in the pit, for a part of each spring.'
'So, they're breeding? Great record.'
'Nope. Show absolutely no interest in that sort of thing. I'm guessing first-summer birds that aren't being tolerated at the main heronries. or Scandi winterers hanging on- the first summer birds go back late.'
Quiet. A sad look, clearly wanted breeders. Well, one of those is right, for sure, but this sort of thing is something the most guidebooks don't really cover. Not all first-summer Grey Herons breed. Small numbers just coming in on dusk, a little squabbling, a chase now and then, but no pairing/courtship seen. Only for that period before hatching and active nesters tolerate congeners in the roost again. I try to make myself think they could be continental birds getting ready to return, but can't quite bring myself to favour that theory- yet. They usually spend the year away from their natal grounds. These birds disappear after a short period. Of course, they could wander I suppose? It pains me not to know (but that could be this is the first write-up of the morning and the meds haven't kicked in yet). Roll on February and March.

This is a bit of a cheat, so I hang my head in shame. I can't really be sure these all stayed in the quarry after dark, but they sure were hunting roosters, and if they had any luck, went to trees on the edge of the pit. Early high counts might represent migrants, perhaps more likely local dispersals. Mid-winter peaks a concentration on prey, similar to numbers hitting a more open Starling roost; flight activity on low count evenings often suggests local residents.
So, yup, perhaps a cheat, but the doctors said I need some incentives to get back on my feet as soon as possible, and seeing if the recent high counts hold up is a good 'un.

Green Woodpecker
Doesn't say much except for there's usually a couple of pairs breed in and around the quarry. Most feeding takes place in the open field around the pit, so inbound flights are relatively easy to pick up. GreWos already present often announce an arrival as they make a territorial announcement, so I'd almost say they were guaranteed- except for that midwinter drop-off. Will this pattern continue?

Great Spotted Woodpecker
Although an odd call alerts you to a bird hidden in the pit, this species is also really easy to pick up flighting in, more often than not from all angles south, presumably from venturing to Rainham's garden feeding stations.

Stock Dove
One of the winter delights for me. Local Stock Dove roosts. I have a couple of regularly-used three figure roosts out in nearby countryside. At both I've seen Stock Doves getting shot at. Sadly, many shooters don't have the discipline of a wildfowler, an appreciation for the subtle differences between the common quarry (Woodpigeon) and the amber-listed off-limits. ("Eh? What's a Stock Dove then?") Sadly, the similar discipline of respect for neighbours is often lacking as well- the shooters are often trespassing.
So, Berengrave being so close as 1,500 metres to highly attractive feeding areas, I've often hoped more would join the Woodpigeons. Not yet to be, the graph reflecting, for the main part, the size and scale of local breeding.
Another example of how such a dull count can help incentivise your birding. Perhaps late December '17 will be the time? (Seriously, I'm on strong medication here.)

Collared Dove
This is a big disappointment. Just over a kilometre north, more than a hundred gather to be fed in the bird-friendliest garden on Motney. A k-and-a-half north-east, similar counts on the local game farm. Collared Doves are known to fly up to seven km to communal roosts, it would seem Berengrave has something going for it, and yet...
a) They want dense cover- thick conifers are used, holly and hawthorn a reasonable choice, and dense ivy another good spot. The first is somewhat lacking, the last something targeted whenever management is thought about. Of course, not every bird does as others, and individual/paired roosting in winter is a norm for many- it seems we have just a few of the local birds showing themselves from time to time.
b) They are wimps. Roosts can often be disturbed by just the threat of potential attack from predators.
c) They readily change sites, and might not return for some time. Where the seven kilometre range comes in handy.
This is the trouble with oft-overlooked species. They make you look harder. This is one species I'd enjoy stumbling on en masse one afternoon, one local roost I'd really like to pin down. (Yes, I write this, post-op laid out in my jimmy-jams, blissfully co-codamal-ed to the point the Bee-Eaters on the cover of Birds of the Western Palearctic are talking to me. But, honestly, I've really wanted that roost for some time now..)

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